UpperBasinPallidSturgeonRecoveryWorkgroupAnnualReportfor
WorkCompletedin2017
TABLEOFCONTENTS
Introduction…………………………………………………………………………………………………………………………………………….1
AnnualGoverningBoardmeetingminutes-August16-17,2017................................................................2
AnnualWorkgroupmeetingagenda–March8-9,2017............................................................................10
AnnualWorkgroupmeetingminutes–March8-9,2017...........................................................................11
UpperBasinWorkgroup2017SummaryRPMA1......................................................................................20
PallidSturgeonPopulationAssessmentandAssociatedFishCommunityMonitoringfortheMissouriRiver:Segment2.........................................................................................................................................34
2017MissouriRiverSamplingfromtheYellowstoneConfluencetoLakeSakakawea…………………………….37
LowerYellowstoneRiverPallidSturgeonProgressReport.........................................................................39
PallidSturgeonPopulationAssessmentandAssociatedFishCommunityMonitoringfortheMissouriRiver:Segments5and6.............................................................................................................................52
Migrations,Aggregations,andSpawningofPallidSturgeonintheYellowstoneRiverduring2017……..…54
Effectofwatervelocityongrowth,survival,andenergyreservesofendogenousPallidSturgeonScaphirhynchusalbuslarvae…...………………………………..…………………………………………………………………………..75
GenotypicAnalysesandParentalIdentificationsofJuvenileandSub-adultPallidSturgeonintheMissouriRiver……………………………………………………………………………………………………………………………………..……………….79
ExaminationofPallidSturgeon(Scaphirhynchusalbus)LarvalDrift,Development,andSwimmingAbilities……………………………………………………………………………………………………………………….….………………..…..91
GeneticIdentificationofLarvalSturgeonfrom2016UpperMissouriRiverLarvalDriftStudy-FinalReportDecember12,2017……………………………………………………………………………………………………………………………..134
OtherSIUCUpperBasinProjects……………………………………………………….……………….………………………......….142
DeterminationofReproductiveIndicesinHatchery-originPallidSturgeonintheMissouriandYellowstoneRivers…………….……………………………………………………………..……..………….………….…………….…….143
2017PallidSturgeonPropagationActivitiesforGavinsPointNFH...................................................…….146
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Introduction
ThisreportdocumentstheworkoftheUpperMissouriRiverBasinPallidSturgeonRecoveryWorkgroup(Workgroup)during2017.ThereportconsistsofminutesoftheannualsummermeetingoftheWorkgroupGoverningBoard,minutesoftheannualWorkgroupmeetingheldinBozeman,MontanainMarch2016,updatesofon-goingworkandreportscompletedbymembersoftheWorkgroupandothercontractors.
TheGoverningBoardoftheWorkgroupduringthisperiodconsistedofthefollowingindividuals.Theirworkaffiliationandthefocusareastheyrepresentareindicated.
ZachShattuck,Chair,MontanaFish,WildlifeandParks
AnneTews,MontanaFish,WildlifeandParks,RPMA1
MatRugg,MontanaFish,WildlifeandParks,RPMA2
LandonPierce,U.S.FishandWildlifeService,RPMA3
TylerHaddix,MontanaFish,WildlifeandParks,Habitat
PatBratten,U.S.GeologicalServices,Research
RobHolm,U.S.FishandWildlifeService,Propagation
KenStaigmiller,MontanaFish,WildlifeandParks,FishHealth
KevinKappenman,U.S.FishandWildlifeService,StockingandTagging
RyanWilson,U.S,FishandWildlifeService
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MeetingNotesfromthe
UBPSWGGoverningMeeting
August16-17,2017
Billings,MT
ThefollowingarethenotesfromtheAugust2017meetingoftheUpperBasinPallidSturgeonRecoveryWorkgroupGoverningBoard.Afewofthediscussionsaregroupedoutoftheorderinwhichtheyoccurredduringthetwo-daymeetingforclarityandtocombinemultiplediscussionsofsingletopics.Asummaryoftheactionitemsassignedduringthemeetingappearsattheendofthemeetingnotes.RyanWilson,TylerHaddix,AnneTews,ZachShattuck,MatRugg,KenStaigmiller,PatBraaten,RobHolm,LandonPierce,BobSnyder,KevinKappenman,LarryGamble,DavidTrimpe,ChristinaGomer,andLouHaneburywerepresentatthemeeting.AttendingbyphonewasBrianMarotz.OpeningCommentsMattMarsh,withWAPA,gavetheopeningremarks.WAPAprovides$300,000annuallytofundUpperbasinprojects.Ifaspecialprojectrequiresadditionalfunding,theremaybeadditionalfundingavailable.MattencouragedcommunicationwithDonSkaar,theMontanarepresentativeonMRRIC,tobringuptopicsandconcernswiththeUSACE.Therewillbeanewregionaldirectorappointedduringthenextfewmonths.
AI–ZachwillsetupameetandgreetconferencecallwiththenewWAPAregionaldirector.LouisretiringattheendofDecember2017.ChristinaGomerwillbetheWAPANEPACoordinatorandtheWorkgroup’scontactwithinWAPA.Duringdrought,WAPAhastoborrowmoneyduetolowflowsandreducedpowergeneration.WAPAisamemberoftheSouthwestPowerPool.RecoveryTeamupdate-GambleWyattDoylefinishedhistenureasRecoveryTeamLeaderasofJuly.LarrypresentedhisideasforreplacingthevacantRecoveryTeamLeaderposition.TheUSFWSisconsideringtwooptionsforanewRecoveryTeamleader.
Shortterm(1yearormore?)–HaveeitherLandonPiercesolely,orLandonandWayneNelson-Stastnyjointlyoccupytheposition.ThiscouldoccurbeforetheendofAugust.AI-LarrysuggeststhattherebeaconferencecallwithLandon,WayneandtheUpperBasinWorkgroupaftertheRTLdecisionismade.
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Longterm–Thedesirableendgoalistoidentifyapermanentcandidateusingthe“GeorgeJordanmodel”wheretheRecoveryTeamLeaderisalsothePallidSturgeoncoordinator.Thisprocessmaytakemorethanayeartocompletebecauseofbudgetissuesandahiringfreeze.
TherewillprobablybeaRecoveryTeammeetingoncethetransitiondecisionismade.
MiddleBasinupdateThebroodstockcollectioncapturedfewerPallidSturgeonthaninpastyears.Theconditionofthecapturedfishwasslightlybetterthanlastyear.Wasmortalityofadultsthecauseoftheincreasedcondition?IntakeDiversionupdate-TrimpeWorkatIntakehasceasedbecauseoftheJuly5injunction.Thereshouldbeahearingbysummer2018.Theprocessforthefinalsummaryjudgmentisexpectedtobea1½-2yearprocess.Thecontractwiththecontractorhasbeenterminated.NoreenWalsh(USFWS)statedthatIntakewillnolongerbeintheUSACE’sbaselinefortheUpperMissouriRiver.Thiswasunexpected.BuRecwillevaluatethePallidSturgeontranslocationprojectatIntakethisfall.BuRecprobablygoingtocontinuerockingexistingweirtoprovidewatertoirrigators.EffectsAnalysis-GambleTheEAteamisworkingonanewmonitoringprogramandisworkingthroughthecommentsontheDEIS.TheUSFWSwillmeetwithRobJacobsonandJoeBonneaunextweek.USFWSwillstresstheneedformoreface-to-faceinteractions,ratherthanrelyingsolelyonaone-wayblogforcommunication.TheUSFWSwantsmorediscussionandinteractivediscussions,ratherthanjustreviewingdraftdocuments.TheEISiscurrentlyscheduledforcompletionsometimeduringthesummerof2018.TheRecordofDecisionshouldbeoutbythefallof2018.FWPupdate–ShattuckFWPPallidSturgeonbiologistsandmanagersfromregions4,6,and7metwiththenewFWPDirectorMarthaWilliamsandAssociateDirectorPaulSihler.FWPwillworktoimprovecommunicationwiththeUSFWS.Workgroupoperatingprocedures–ShattuckZachpresentededitstotheexistingoperationproceduresdocument.HewillsendadraftouttoGoverningBoardmembersfortheirreview.
AI-CommentsondraftchangestooperationalproceduresdocumentshouldbesenttoZachbySeptember8,2017.
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WorkgroupMemorandumofUnderstanding–ShattuckThecurrent(2008)MOUwillexpireinJuly2018.LoustatedthathavingcontractorssigntheMOUsimplifiesWAPAcontractingpractices,asindividualcontractingnegationswouldnotberequired.AsimplereferencetotheMOUwouldsuffice.
AI–ZachwillworkwithLandonandLoutogettheupdatedWorkgroupMOUapprovedandsigned.
FacilitatorMOU–ShattuckThisMOUneedsrenewal.
AI–ZachwilldraftanupdatedfacilitatorMOU.RPMA1update–TewsAnnegaveaPowerPointpresentationaboutthenewPITtagsystemthatwasexperimentallyusedinRPMA1.Thissystemusesthenewstandardfrequency(134.2kHz)fortagginganimals.Ituseseither12.5mmor23.5mmPITtags.ThenewPITtagsareinsertedintheabdomenoffishusinganincision.The125kHztagscurrentlyusedareobsolete.Thenewtagsarecheaper($1.70vs.$3.10).Thecurrentinventoryof125kHztagscanbeexchangedfornewtags.AnnesuggeststhenewsystemandstandardbeadoptedintheUpperBasin.Thecurrenttaggingprotocolencouragesadoptingthenewstandard,butdoesnotindicatehoworwhenitshouldbedone.GuidanceastohowtoproceedtoupdatetheTaggingandsamplingProtocoltoadoptthenewsystemwillberequestedfromtheRecoveryTeam.
AI-Kevinwillleadtheefforttoupdatethetaggingandsamplingprotocoltoconvertfrom125Khzto134.2kHzsystems.
Thefirststepwillbetoacquireandemploydualfrequencyreaders.WAPAfundingcanbeusedforthis.LourequestedthatWAPAreceiveadescriptionofwhatisrequiredtoconverttothenewsystem.
AI-ZachwilldraftandsendalettertotheUSFWSthatincludesadetailedproposaltoconverttothenew134.2kHzsystem,includingtheprosandconsandhowthetransitioncouldoccur,andrequestingrecoveryteamandUSFWSapprovaltobeginimplementationofthenewsystem.
AI-ZachandKevinwillcoordinatethetransitiontothenewPITtagsystem.
RPMA2update–WilsonLackofgrowthofstockedPallidSturgeonisaconcern.Therearefew’07and’08ageclassesthataregreaterthan500mm.Hatchery-stockedPallidSturgeonhavebeennettedinLakeSakakawea.Highflowsmadecapturingadultbroodstockdifficult,butninefishweresenttoGPNFH.
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TheDepartmentofJusticehasfundingforcontaminantssampling.Tyler,Mat,RyanandtheircrewswillattendsamplingtrainingandperformsamplinginitiatedbecauseoftheoilspillsintheYellowstoneRiver.MilkRiver/MissouriRiverupdate–HaddixTheMilkhadlowflowsin2017,soTylerdidn’tseemanyPallidSturgeonusetheMilk.Fewlarvaeweresampledaswellasjuveniles.PallidSturgeonthatstaybelowFortPeckDamarethinanddon’tgrow,probablyduetolowtemperaturesandpoorproduction.Yellowstoneupdate–RuggPaddlefishhavebeenfoundintheBigHornRiverduetoextendedhighflows.ThePallidSturgeontranslocationprojectcaptured,taggedandmovedfivePallidSturgeonfrombelowIntakeDam.AnyPallidSturgeoncaughtbetweenIntakeDamandthemouthofthenaturalsidechannel,weretranslocated.Twowildmalesandonejuvenilemalewerelocatedmorethan100milesupthePowderRiver.ThreePallidSturgeonusedthenaturalsidechanneltobypasstheIntakeDam,butrapidlyreturnedbackdownstream.PallidSturgeonspawningtelemetryupdate–BraatenThreefemalePallidSturgeonweretrackedtonormalspawningareasnearFairview.Freeembryoscapturedbelowthesitesconfirmedthattheyspawned.AdyereleasewasconductedattheGlendiveboatramp.RPMA3update–PierceLownumbersofPallidSturgeonwerecaughtthisyearduetohighflows.RPMA3fisharedisplayinglowgrowthratessimilartowhatisobservedinRPMA2fish,althoughtheyachievelargertotallength.SouthDakotahasceasedpopulationassessmentactivitiesupstreamofSegment7.Landon’sofficemaytakeonthework.220PallidSturgeonhavebeendocumentedtohavemoveddownstreampastdam.MilesCityHatcherypropagationupdate&fishhealth–StaigmillerMCSFHdoesnothavePallidSturgeonthisyear.FWPmusthaveinternaldiscussionaboutMCFHS’sparticipationinthePallidSturgeonprogram.SNSfromWyomingarepositiveforiridovirus.
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Driftstudyupdate–BraatenandHaddixEdHeistidentified58PallidSturgeonofthe1269freeembryosamplescollectedduringthedriftstudy.Allbuttwocamefromthefirstnight’ssample.Thetwootherswerefromthesecondnight’ssampling.“Walls”ofsamplingatCulbertsonandWillistondidnotcaptureanyPallidSturgeon.Flowswereapproximately10,000cfsduringtherelease.Whathappened?Edwasalsosent450YOYsturgeonsamplesforidentification.Resultsarepending.GarrisonDamNFHpropagationupdate–HolmGDNFHhadtenfishfromtheconfluenceforspawning.ThereweretwofemalesfrombothRPMA1andRPMA2.Robletsfishrecoverpost-spawnpriortobeingreleased.Robhas227progenyfromthefemalethatdiedthisspring.Allmaleswereincludedinthecryo-repositoryinWarmSprings.Spermusedfromthe2001cryo-preservedmaleshadhighfertility.Spawningmatricesarebeingusedtocreate“boutique”matingstoequalizegeneticrepresentationamongtheUpperBasinRPMAsandtoincreasetheireffectivepopulationsize.Earlylife-stagemortalityisasourceofundesirablenon-randomhatcheryselection.Robisobservingvariableutilizationoffeedamonglots.Robbelievesitmaybeduetoproblemsrelatedtoenzymesinvolvedinfeedutilization.RobwouldlikethePropagationCommitteetorevisitearlylife-stagemortality.
AI–SnyderwillcontactMollyaboutanearlylife-stagemortalityconferencecall.
Thecurrentstockinggoalsforspringyearlingsin2018are:RPMA1 RPMA2 RPMA31500 1500 110RobneedsthenumberstobestockedbyfamilyfromtheRPMAbiologistsbyOctober1sothathecanmanagehisinventory.
AI–RPMAbiologistsneedtogiveRobtheirnumbersoffishstockedbyfamilybyOctober1.SurvivalestimatesJayhasreleasedadraftofthelatestsurvivalestimates.Theestimatedsurvivalsoffall-andspring-stockedPallidSturgeonhavechangedfromearlierestimates.Ryanstatedthatthesurvivalestimatesareunderestimations.Ryanaskedifweneedtoincreasetheeffortoverashortperiodoftimetoimprovethenumbersoffishcapturedandimprovesurvivalestimates.TheGoverningBoarddecidedtoscheduleaconferencecallattheendofSeptemberandameetingattheendofthedayofthecontinuingeducationtrainingworkshopinconjunctionwiththeMarchworkgroupmeetingtodiscusssurvivalestimationwithJay.
AI–ZachwillsetupconferencecallbetweenbiologistsandJay.Afollow-upmeetingwilltakeplaceinconjunctionwiththeWorkgroupmeeting.
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StockingplanRotella’ssurvivalestimatesdifferfromthevaluesusedintheoriginalstockingplan.Thepurposeofstockinghaschangedfromdemographicgoals(numbers)tomaximizingeffectivepopulationsize.Thestockingplanneedstobere-written.
AI-Snyderwillcoordinatethere-writeofthestockingplanfortheUpperBasin.HewillinvestigatehowtheRange-wideStockingPlancanbemodulizedtopermiteasierbasin-specificchanges.CommentsandsuggestionswillbesenttotheRecoveryTeamLeaderandLarry.
InvasiveproceduretrainingRobobservedapoorly-healed,twoyearoldincisioninoneofthebroodstockandisconcernedthatthosethatuseinvasivetechniques(transmitterimplantation,sexingandassessmentofreproductivestatus)arenotbeingadequatelytrained.HebelievesthatthesepeopleneedtobefamiliarwiththeanatomyofPallidSturgeontoavoidcausingdamagetointernalorgans.Kevinsaidthatthereisalegal,(i.e.lawenforcement),riskhavinguntrainedpeopleperforminvasiveprocesses.Itwasdecidedthatstudents,techniciansandbiologistswillbegiventraining,asneeded,toreducedamageandmortalityforminvasiveprocesses.KevinsaidtheyhavelotsoffishavailableattheBFTCfortraining.HeiswillingtoleadatrainingworkshopattheBFTC.AnnesuggestedRobmakeavideothatcouldbedownloadedandaccessedinthefield.CanUSFWSpermitsrequiretrainingofpermitholders?
AI-LarryandRyanwillinvestigateamendingpermitlanguagetorequirehandlingtraining.AI-ZachwillinvestigateifitispossibletoamendFWPcollectors’permitstorequiretraining.AI-Kevin,RyanandZachwilldevelopinvasiveproceduresworkshoptrainingrequirements.AI–Kevinwillcoordinateinvasiveprocessestraining.
Itwasagreedthatspringwasthebesttimefortraining.ZachsuggestedthatacontinuingeducationsegmentbeaddedtotheMarchWorkgroupmeeting.TheGBagreed,thereforetheMarchWorkgroupmeetingwillbeheldinBozeman.WAPAFunding–HaneburyThedraftproposalforFY18WAPA-fundedprojectswillbeavailableinDecember.LouencouragedWAPAcontractorstosendininvoicesassoonaspossible.WAPAfundingisusuallyavailableforthreeyearsfromapprovaldate.Overheadrateshaveimpactedanddelayedapprovalandfundingofsomeprojects.
AI–LouwillsendZachWAPA’spolicyontransmitter/receiverpurchasing.
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WebsiteimprovementsLouofferedimprovementstothePallidSturgeonwebsite.TheGoverningBoardwouldliketohavealibraryofdocumentspostedonthewebsite,althoughthiswillrequirelimitedaccesstothelibrary.Ataminimum,weshouldmakeavailableabibliographyofPallidSturgeonliteratureincludingrecoveryandconservationdocuments.
AI-Snyderwillworkonthebibliography,libraryandwebsiteaccessissue.
UpperBasinWorkgroupChair–ShattuckZachwasapprovedbytheGoverningBoardtoanothertwo-yeartermasWorkgroupChairperson.FY2018Workplan–ShattuckTheGoverningBoardreviewedanddiscussedtheproposalssubmittedforWAPAfundinginFY18.GoverningBoardmemberswillsendtheirselectionsforapprovaltoZachbytheendoftheweek.TheUpperBasinWorkgroupmeetingwilltakeplaceinBozemanonMarch6-8.Thiswillincludeaninvasiveproceduresworkshop,ameetingwithJayregardingsurvivalestimates,andtheWorkgroupmeeting.
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SummaryofActionItems1. ZachwillsetupameetandgreetconferencecallwiththenewWAPAregionaldirector.2. LarrysuggeststhattherebeaconferencecallwithLandon,WayneandtheUpperBasinWorkgroup
aftertheRTLdecisionismade.3. CommentsondraftchangestooperationalproceduresdocumentshouldbesenttoZachbyAugust
31,2017.4. ZachwillworkwithLandonandLoutogettheupdatedWorkgroupMOUapprovedandsigned.5. ZachwillworkwithLandonandLoutogettheupdatedWorkgroupMOUapprovedandsigned.6. ZachwilldraftanupdatedfacilitatorMOU.7. Kevinwillleadtheefforttoupdatethetaggingandsamplingprotocoltoconvertfrom125Khzto
134.2kHzsystems.8. ZachwilldraftandsendalettertotheUSFWSthatincludesadetailedproposaltoconverttothe
new134.2kHzsystem,includingtheprosandconsandhowthetransitioncouldoccur,andrequestingrecoveryteamandUSFWSapprovaltobeginimplementationofthenewsystem.
9. ZachandKevinwillcoordinatethetransitiontothenewPITtagsystem.10. SnyderwillcontactMollyaboutanearlylifestagemortalityconferencecall.11. RPMAbiologistsneedtogiveRobtheirnumbersoffishstockedbyfamilybyOctober1.12. ZachwillsetupconferencecallbetweenbiologistsandJay.Afollow-upmeetingwilltakeplacein
conjunctionwiththeWorkgroupmeeting.13. Snyderwillcoordinatethere-writeofthestockingplanfortheUpperBasin.Hewillinvestigatehow
theRange-wideStockingPlancanbemodulizedtopermiteasierbasin-specificchanges.CommentsandsuggestionswillbesenttotheRecoveryTeamLeaderandLarry.
14. LarryandRyanwillinvestigateamendingpermitlanguagetorequirehandlingtraining.15. ZachwillinvestigateifitispossibletoamendFWPcollectors’permitstorequiretraining.
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Upper Basin Pallid Sturgeon Workgroup MeetingMarch 8-9, 2017
Red Lion Hotel and Conference Center1223 Mullowney Ln.Billings, MT 59101
(406) 248-7151https://join.freeconferencecall.com/zshattuck
zshattuck(712) 451-0200
875393
Wednesday (3/8) Time (MST): Topic: Speaker(s):
10 min 0800-0810 Introductions and opening remarks Zach Shattuck, Bob Snyder
10 min 0810-0820 Pallid Sturgeon Recovery Team and MB, LB Workgroup updates Wyatt Doyle
20 min 0820-0840 Pallid Sturgeon telemetry project in RPMA 1 Chris Guy20 min 0840-0900 Missouri River above Ft. Peck Reservoir monitoring and telemetry Anne Tews, Mike Schilz20 min 0900-0920 Hatchery-reared Pallid Sturgeon telemetry in RPMA 2 Landon Holte20 min 0920-0940 Pallid Sturgeon movement and spawning in the Yellowstone River Pat Braaten20 min 0940-1000 Yellowstone River native fish telemetry study Mat Rugg
10 min 1000-1010 Break
20 min 1010-1030 Update on the 2016 Pallid Sturgeon free embryo dispersal experiment Pat Braaten20 min 1030-1050 Update to 3D river-mapping efforts during the 2016 Missouri River drift study Brian Marotz20 min 1050-1110 Update on Carrying Capacity Study in RPMA 2 - fish Addie Dutton20 min 1110-1130 Update on Carrying Capacity Study in RPMA 2 - macroinvertebrates Eric Scholl
120 min 1130-1330 Lunch
30 min 1330-1400 Update on the MRRMP-EIS and BiOp Doug Laye30 min 1400-1430 Upper Missouri River Basin Effects Analysis Robb Jacobson10 min 1430-1440 Missouri River Recovery and Implementation Committee Don Skaar
15 min 1440-1455 Oil-spill response training and baseline monitoring for Pallid Sturgeon David Rouse, Karen Nelson, Don Tillitt15 min 1455-1510 Redwater River fish passage improvement Steve Dalbey
10 min 1510-1520 Break
20 min 1520-1540 Broodstock collection coordination in RPMA 1&2 Group Discussion30 min 1540-1610 Translocation of Pallid Sturgeon at Intake Group Discussion20 min 1610-1630 10-year strategy, furthering recovery, RFP process, outreach opportunities Zach Shattuck, Bob Snyder
Thursday (3/9) Time (MST): Topic: Speaker(s):
20 min 0800-0820 Segments 1-3 (Ft. Peck Dam to Confluence) Landon Holte20 min 0820-0840 Segment 4 (Confluence to headwaters of Lake Sakakawea) Ryan Wilson20 min 0840-0900 Segments 5-6 (Ft. Randall Dam to headwaters of Lewis & Clark Lake) Landon Pierce20 min 0900-0930 Monitoring objectives and protocols for Upper Basin in PSPAP 2.0 Group Discussion
20 min 0930-0950 Wild-caught Pallid Sturgeon genetics monitoring Meredith Bartron, Jeff Kalie10 min 0950-1000 Hatchery-reared and released Pallid Sturgeon reproductive indicies Molly Webb10 min 1000-1010 Gavins Point captive broodstock monitoring Molly Webb
10 min 1010-1020 Break
20 min 1020-1040 Garrison Dam NFH Rob Holm20 min 1040-1100 Gavins Point NFH Chris Hooley20 min 1100-1120 Miles City FH Mike Rhodes, Cory Hagemeister
10 min 1120-1130 U.S. Fish & Wildlife Service Wyatt Doyle10 min 1130-1140 Western Area Power Administration Lou Hanebury10 min 1140-1150 NorthWestern Energy Steve Leathe10 min 1150-1200 U.S. Bureau of Reclamation David Trimpe10 min 1200-1210 U.S. Army Corps of Engineers
20 min 1210-1230 TBA Zach Shattuck, Bob SnyderOther Items, Discussion, & Closing
Movement & Spawning
Larval Drift and Carrying Capacity
Agency Updates
Population Assessment Sampling & Monitoring
Hatchery Updates
Welcome & Housekeeping
Recovery Team & Workgroup Updates
Workgroup Coordination
Genetics & Broodstock
Effects Analysis & Missouri River Recovery Program
Online Meeting Link:Online Meeting ID:
Call-in Number:Participant Code:
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2017UpperBasinPallidSturgeonWorkgroupMeeting
March8-9,2017RedLionHotelBillings,MT
WyattDoyleEachWorkgroupneedstoidentifypriorityresearchandmonitoring.Identifythebiggestissueinthebasinandhowwe’dliketotackleit.IdentifyhowtheFWScanincorporateintomanagement.TheLowerBasinWorkgroupidentifiedmicrochemistryandrecruitmentastheirmainissues.TheMiddleBasinidentified“skinnyfish”astheirmainconcern.WyattwillbesteppingdownasRecoveryTeamLeader.ChrisGuy–RPMA1telemetrystudyThenewprojectinRPMA1willstudythereproductiveecologyofhatcheryandwildpallidsturgeon.OneobjectiveistodetermineifwecangetpallidsturgeontospawnfarenoughupstreamofFortPeckReservoirtoallowsufficientdrift.Luke’stelemetryprojectdeterminedthattheearliesthatchery-originpallidsturgeonmalesmaturedis14years.Forfemales,itis18years.Somemalesexhibitedabiennialcycle.Bothhatchery-originandwildreproductivemalesmadesimilarmovements.Non-reproductivemalesdidn’tmovemuch.ThemaximummovementisslightlyupstreamoftheFredRobinsonBridgearea.Ofreproductiveadults,60%ofmaleswereclusteredapproximately50kmofriverbymidtolateMayin2015.In2016,40%wereclusteredin20kmofriver.Forspawning,aminimumwatertemperatureof24ͦ°CisneededabovetheMarias.Allfemaleswentatretic.Furtherresearch:Identifyhabitatcharacteristics;determinewhyfemalesaregoingatretic;anddetermineifmalesarespawningand,ifso,withwhom?The2017projectwillfocusonidentifyinghabitatcharacteristics,determiningthecauseofatresia,investigateifthefemalesaremaking“dummy(conditioning)runs”,anddeterminewhatspawningcuesareneededandifsomearemissing.
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AnneTews–SturgeonSamplinginRPMA1Estimatesofshovelnosesturgeonpopulationweremadewithmorethan100netdrifts.Asimilareffortin2009wasrepeatedin2015atFredRobinsonand1995and2008estimateswererepeatedin2016atCoalBanks.Theresultsindicateadeclineinshovelnosesturgeon:
SNSestimatesintwoRPMA1reaches
ShovelnoseSturgeonwentfrom1300permileto670permile.Annesuggeststhisdecreasewasduetolowreproductionduringthedrought.Pallidsturgeoncapturesvariedfrom0to0.25pernet.Theyaveraged2mmperyeargrowth.Oneshovelnosesturgeonwasrecaptured37yearsafteritsoriginalcapture(approximately60yearsold).A2002hatchery-producedSNSwithfincurlsurvived.Thereisagoodopportunityforbroodstockcollectionin2017.LandonHolte–Missouri/MilkHRPStelemetryThereare132telemeteredpallidsturgeoninstudyreach,mostare2002year-class.Four1997age-classhatchery-originpallidsturgeonusedtheMilkRiverin2016duringJuneandJuly.A1997age-classfemalespent1.5monthsintheMilkRiver,butherreproductivestatusisnotknown.NoextantadultsmovedintotheMilkRiver.Sixty-twopaddlefishand16sturgeon(undetermined,geneticsamplessubmitted)werecapturedduringlarvalsampling.A1997femalemovedasfarasIntake.Herreproductivestatusisunknown.In2016,thelargestsampleofYOYsturgeon,withawiderangeofsizeswerecaughttodate.Geneticidentificationispending.Theyareseeingmovementsofspawningfish.Itmaybedesirabletocapturethesefishandidentifytheirreproductivestatus.
Year CoalBanks FredRobinson
1995 8700
2005 8518
2009 2078
2015 2898
2016 4386
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MatRugg–YellowstoneRivernativespeciestelemetryThisprojectinvestigateshowthecurrentIntakeDamstructureaffectsfishmovement.Pallidsturgeon(hatchery-originandwild),bluesuckers,sauger,shovelnosesturgeonandpaddlefisharethespeciesinvestigated.OnehalfofyearlingpallidsturgeonintheGlendivereachmovedupstream.NopallidsturgeonatIntakemovedupstream.Inearlytomid-Maypaddlefishmovedto,butnotaboveIntakeandthendisplayedabigmovementtotheMilkRiver.MosttelemeteredSaugerandBlueSuckerwereabletomovepasttheexistingstructure,withmostSaugermovingJunetolate-JulyandBlueSuckermovingmid-Aprilthroughlate-June.ThreeShovelnoseSturgeonmovedupstreamofIntakeatlowerflowsinJuly;perhapsexhibitingsomeinherentdifferencesbetweenShovelnosesandPallids.Also,twoShovelnoseSturgeonthatwerefoundintheYellowstoneRiverwerealsocontactedintheMilkRiverinMay.BraatenwillwriteapproachtotranslocationprojectatIntake.TheUSBRAMPallowsforatranslocationproject.PatBraaten–PallidSturgeonmigrations,aggregationsandspawningintheYSRTherewerenoknownreproductivefemalesforthe2016assixfemaleswerecapturedandusedtoproducefreeembryosforthedriftstudy.Thereweremanyreproductivemales.Manypallids(14%oftelemeteredpopulation)moveduptoIntakeMay5-7andthenmovedbackdowntoaggregateinlower10milesoftheYellowstoneRiver.NotelemeteredfishmovedpastIntakeDamthroughthenaturalsidechannel.Notallfisharemigrators,someare“homebodies”.Threehundredandfifteenfreeembryosandlarvaewerecapturedbelowsuspectedspawningaggregations.Geneticanalysisispending.PatBraaten–DispersalofpallidsturgeonfreeembryosintheMissouriRiverThelarvaldrifthypothesisis:“Underexistingconditions,thereisaninsufficientlengthoffree-flowingriverinehabitatavailablebetweenspawning(hatch)andsettlinglocationsinfragmentedriverreachesforpallidsturgeonfreeembryostocompleteontogeneticdevelopment,transitiontobenthic-orientedlarvae,andsurvive.”Thestateofsciencerelevanttothelarvaldrifthypothesis:
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1. Recruitmentfailure/curtailmentpost-57.2. Confirmedspawning.Shortdriftdistance,norecruitmentdetected.3. Confirmedspawning,longdriftdistance,norecruitmentdetected.4. Mortalityofpallidsturgeonearlylifestage(ELS)inriver-reservoirtransitionzones.5. SurvivalofpallidsturgeonELSinheadwatersofLakeSakakawea.6. Fateofslowdrifters,settlement,andsurvivaloffreeembryos.7. Hydraulicdriversoffreeembryodispersal.
a. “Some”survivalpredictedfrommainstemlarvaldriftmodels.b. Nosurvivalpredictedfromhydraulicmodels.
ModelingiscentraltoMissouriRiverEffectsAnalysisandManagementPlan.Objectivesofstudy:
1. Quantifypre-settlementdriftanddispersalattributes.2. Identifysettlinglocationswherepallidsturgeontransitionfromdispersingfreeembryosto
settledbenthiclarvae.3. Identifyandquantifyhydraulicelementsdrivingfreeembryodispersalandlarvalsettlement.4. Testexistingdispersalmodelsanddevelopmorerefineddispersalmodels.
Forthestudy,697,00freeembryos(<2dayspost-hatch)werereleasedintotheMissouriRiverbelowFortPeckDam.Twobeadtypeswithdifferentdensitieswerealsoreleasedtoseeiftheycouldbesurrogatesforfreeembryos.Benthictrawlingwasperformedinstudyreachtodetectsettledlarvae.450Scaphirhynchussp.Settledlarvaewerecaptured(themostcapturedsincetrawlingbeganin2002).Geneticresultsarepending.BrianMarotz–EstimatingthespeedandpathwaysofdriftingpallidsturgeonfreeembryosMorethan200milesoftheMissouriRiverweremapped9milkRivertoWilliston).Channelbedformandhydrauliccomplexitycontrolslarvaldriftspeedandpathways.Fastestdrifter(10%)couldreachLakeSakakaweain6.5daysiftheyremaininthalweg.Ninetypercentaresweptfromthalwegintolowvelocityhabitats,extendingriverresidence.Morethan50%stalledalongriverbanks,islandsandchannel-spanningsanddunes.Thesefishwouldhavetore-suspendtocontinuedrifting.DriftersnearthebottomwouldnotreachLakeSakakaweafor31days,indicatingdriftdurationmaynotbelimitingpallidsturgeonrecruitmentdownstreamofFortPeckDam.DougLaye–BiOpDougistheSection7leadforMRRMPBiOpandwastheprimaryauthoroftheIntakeBiOp.HeishelpingtheUSACEputtogethertheBiologicalAssessmentfortheMPPMP,scheduledtobecompletedbyfallof2017.TheFWShas90daystoconsultand45additionaldaystoproducefinaldecision(BiOp).
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PatBraatenandRobbJacobson–EffectsAnalysisTasksfor2017:
1. CompleteMiddleBasinfishconditionreport2. Developrecommendationsforupdateofpallidsturgeonpopulationassessmentprogram.
(March21workshop)3. Development,deploymentandapplicationofcollaborativepopulationmodel.4. SetuptransitiontoTechnicalTeam5. RefinesciencecomponentsasAMplanisrevised.
DonSkaar–MRRICMRRIChas28members.DonistheMontanarepresentative.TherewillbeanimportantmeetinginAugusttoassessallperspectivesandconcernswithinMRRIC.Thereareconcernsinthelowerbasinaboutchangestothecurrentmastermanual.EricScholl–CarryingCapacityProject(macroinvertebratefoodresources)Twoscenariosareconsidered:sturgeonarefeedinginproportiontohabitattypesandsturgeonareonlyobtainingfoodfromsandhabitats.Shovelnosesturgeon-22%oftheirmacroinvertebratedietsnotassociatedwithsand.Pallidsturgeon–46%oftheirmacroinvertebratedietsnotassociatedwithsand.Plansfor2017include:
Completionoflabworkbyspring.Refinemacroinvertebrateproductionestimates.Buildtrophicsupplyanddemandmodelforpallidandshovelnosesturgeonbyearlyfall.
AddieDutton–PallidsturgeonfoodwebLookingatthedietsofpallidandshovelnosesturgeon;emeraldshiner,flatheadchub,sturgeonandsicklefinchubs;goldeyes;stonecatsandchannelcatfish.Thefoodwebisverycomplex.Somespeciesarespecialistsandsomearegeneralists.SteveDalbey–RedwaterRiverFishPassageFishpassageintheRedwaterRiverwasadverselyaffectedbythepoordesign(aseriesofperchedculverts)ofacrossingstructure.Thisimpactedpallidsturgeonbylimitingforagefishproduction.Thisstructurewasreplacedwithadesignthatallowfishpassage.In2015sevenspeciesmovedabovethestructure.Thereisanotherbarrier2milesupstreamthatrequiresreplacement.
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DavidRouse–OilspillresponsetrainingandbaselinemonitoringforpallidsturgeonTheobjectivesofthisprojectare:
1. Pallidsturgeonriskassessmentandresponseplandevelopment2. Oilspillpreparednessfishhealthsamplingtrainingandbaselinesampling.
Thefishhealthassessmentwilllookatthepresenceandeffectsfrompolyaromatichydrocarbons(PAHs).LookingtohavesamplingandtraininginearlyJune(orasfieldstaffdictateotherwise).Threesamplesfromthreelocationsofpallidsturgeonhabitat(belowMo/YSRconfluence,YSRaboveconfluence,andMoaboveconfluence)willbecollectedtargetingpallidsturgeonorsurrogatespecies.Lookingfor10ofeachsexfrombenthicspecies.Helpisneededtoscheduletrainingandsampling,perhapsJuly?LarryGamble–PallidsturgeontranslocationTranslocationisaninterimeffortatIntakeDamtobenefitpallidsturgeon.Translocationhasbeenidentifiedasarecommendationtooffsettake.USACEandUSBRaretaskedwithperformingthetranslocationsandcomingupwithdecisioncriteria.Perhapsapilotstudywouldbebestfor2017andtheshortamountoftimetoprepareastudydesign,withamoredevelopedapproachin2018.LandonHolte–Populationassessmentinsegments1-3Captured79pallidsturgeonrepresenting13ageclasses(2001-2015)in2016.2016hadreducedsamplingeffortduetoprogrambudgetcuts.Atotalof25bendsweresampledusingonlytrammelnetsandtrotlines.Noottertrawlsorfykenetswereused.Samplingin2017willbethesameas2016.Tylercommentedthattheyhaveobservedadecreaseinchubsfrom2006-2015.RyanWilson–Populationassessmentinsegment4Capturedatotalof191pallidsturgeonin2016(175HRPs,16wild).Thehabitatinthesegmenthasshifted,makingtargetedsamplingmoredifficult.2002ageclasspallidsturgeoncontinuetogrowfasterthansubsequentlystockedageclasses.Captureofsturgeon,sicklefinandflatheadchubscontinuestodecrease,asitappearsthathabitatinlong-termsamplingareahasshifted.Withfuturedevelopmentofpopulationassessmentprogram,thereisaneedtoincludeallsegmentstodetectchangesinabundanceforPallidsandotherspecies.
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LandonPierce–Populationassessmentinsegment5and6Sixty-ninepallidsturgeonwerecapturedin2016.Nonewerewild.Relativeweightsvariedfrom.86-.94.The1997-1999ageclasseshadhighergrowthratesthansubsequentageclasses.Stockedpallidsturgeonsuccessfully(~94%survival)passdownstreamthroughGavinsPointDam.PSPAP2.0discussionItwasrecommendedthatallsegmentsneedtobeincludedtoseeiftherearerealtrendsinabundanceofpallidsturgeonandotherspecies.Alldatashouldbeincludedinanyanalysis.Itwasrecommendedthatmorethanjustpallidsturgeondataisneeded.Informationaboutthecommunityisneeded.Whatarepallidsturgeondoingastheymature?Wyattsuggestedweneedtostatetheassumptionsinthecurrentplanandwhatneedstobeincludedinfuturemonitoringprogramstoeffectivelymonitorstatusofpallidsturgeon.Willtheforagebasecollapseinthenext10years?Whatisthepopulation’sreproductiveviabilitylongterm?Whatdoweneedtomonitortoassessthecommunity?Recommendedobjectivesforthefuturemonitoringprogramshouldinclude:
1. Quantifyandevaluateannualtrendsinpallidsturgeonpopulationstructure.2. Quantifyandevaluateannualtrendsintheassociatedcommunitiesoffish,includingshort-term
effectsonspeciessuchaschubs.3. Thereshouldbeannualreportsandbiannualsynthesisofresults.
Danewillsendoutalistofbaselineobjectives.Tyler,Mat,Ryan,LandonandDanevolunteeredtohelpdevelopPSPAP2.0.JeffKalieandMeredithBartron–Annualpallidsturgeongeneticanalysis993sampleswereanalyzedin2016.ThreehybridswereidentifiedfromRPMA4andatriploidwasidentifiedfromRPMA2.Therearecurrently98malesinthecryo-preservationrepository.Theduedatesfor2017samplesare:
Potentialbroodstock 5/5/2017Fishofunknownoriginsforspring 6/9/2017Fishofunknownoriginsforfall 11/10/2017
MollyWebb–Determinationofreproductiveindicesincaptiveandhatchery-originpallidsturgeonThereare19ageclassesinthecaptivebroodstockatGavinsPointNFH.
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SexescanbedifferentiatedatAge1.Captivebroodstockreachfirstmaturityat9years(females)and4years(males).Hatchery-originstockedfishreachsexualmaturityat18years(females)and10years(males).Typically,captivefemaleshaveatwo-yearspawningcycleandmaleshaveeitheraone-ortwo-yearspawningcycle.Femalestotargetin2017springcollectionareCode86(RPMA1)andCode203(RPMA2).Mollywillsendoutalistofneedsforfishandnecessaryequipment.RobHolm–GarrisonDamNFHIn2010stockingofpallidsturgeonmovedfrommaximizingnumbersoffishsockedtomaximizingeffectivepopulationsize.Freeembryosweresuppliedforthe2016driftstudy.MRSIV-positivefishstockedintoRPMA4appeartobesurviving.Thereisaneedtodiscussmodifyingthegeneticsmanagementplan.DomanagethegeneticstructureofeachRPMA’spopulationsoallRPMAshaveallfamilygroupsordowemanagetheUpperBasinasasinglepopulation?IsitgoodenoughiffisharerepresentedwithintheUpperBasinordotheyneedtoberepresentedinallRPMAs?WeneedtodeveloptheUpperBasin’sperspectiveinthegeneticsmanagementplan.WeneedtoprioritizeproductionoffamilygroupsbyRPMA.ChrisHooley–GavinsPointNFHNinefemalesand8maleswerespawnedfromthecaptivebroodstockin2016.AllfishspawnedarenotrepresentedinanyRPMA.RPMA1ismissingrepresenttationfrom16females.RPMA2ismissingrepresentationfrom7females.RPMA3ismissingrepresentationof6females.GPNFHisatcapacityforcaptivebroodstock.Managingforindividualfishratherthanfamilywillsaveroom.GPNFHisrehabbingandspawningcapturedadultsfromRPMA4.MikeRhodes–MilesCitySFHFincurlhasbeenanissuein2015(1of3families)and2016(allfamilies)infishheldonYSRwater.Finsarecurlingdown,whilefinsatBFTCcurledup.Whatdowedoiffincurlcontinues?
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LarryGamble&WayneNelson-Stastny-USFWSUpdateItisproposedthattheRecoveryTeamLeaderbeafullyfundedposition.Thereisahiringfreeze,sotherewillhavetobean“acting”rolefor6monthsormore.Wayneunderstandstheneedtoapproacheachbasinuniquely.Intakeaffectsthestatusofpallidsturgeonbutnotconservationorimpacts.TheUSFWSmaybelookingattheUpperBasinWorkgrouptodeterminewhataretheimpactsfromFortPeckDam,bothupstreamanddownstream.LouHanebury–WAPAUpdateThereareissueswithfundingacoupleoftheprojectsproposedforWAPAfundingfor2017.Contractsshouldbecompletedinthenextseveralweeks.SteveLeathe–NorthwestEnergyUpdateNewfundsforworkinRPMA1,includingsomeequipmentandtelemetrystations;riparianrestoration;long-termripariansongbirdmonitoring;andriparianfencingbyBLM.DavidTrimpe–BureauofReclamationUpdateThefinalEISforIntakeDamhasbeencompletedandtheRODwasissuedonDecember2,2016.TheUSBRandUSACEarerequestingthattheinjunctionbelifted.AhearingisscheduledforApril5.MonitoringhasnotdetectedanyScaphirhynchusfreeembryosattheIntakeheadgate.Methodologymayneedtobeadjusted.ThereisanewNEPACoordinatorforWAPA;Kristina.PrioritiesandResearchneedsSendprioritiesorresearchneedstoZach.HewillcompilethemandsendthemtoWyatt.IncludeBartron/Kaliegeneticsprojectasaresearchneed.
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UpperBasinWorkgroup2017SummaryRPMA1AnneTews,RobBeattieandMikeSchilz
March27,2018
SUMMARY
ThisreportsummarizesPallidSturgeonrecoveryeffortsfor2017inRecoveryPriorityManagementArea1(RPMA1),upstreamfromFortPeckReservoir.GametesfromonewildmaleandtwopreviouslyunrepresentedwildfemalePallidSturgeonfromRPMA1weresuccessfullyincorporatedintothe2017hatcheryprogram.Onefemalediedatthehatcheryafterspawning.Therewere414PallidSturgeoncaptures,with3wildand12fishfromthe1997-yearclass(PS-97)captured.HRPSfromPS-05throughPS-15werealsocaught.PallidSturgeoncatchrateduringthestandardfallpopulationassessmentwasthesecondhighestonrecordandwasmuchhigherthanseenforthepastthreeyears.PS-97aremuchlongeratAge9thanthenext3oldestyearclasses(PS-5,PS-06,andPS-07).Seventy-eightPallidSturgeon,primarilyPS-97,weremonitoredwithradiotelemetryin2017.FWPhad1759contactswiththesefish.Thirty-onepercentwerelocatedatleastonceupstreamofJudithLandingatrivermile(RM)1984.Oneradio-taggedmaturemalePS-97wasrecordedupstreamofFortBenton.TwoPS-97wererecordedintheMariasRiverin2017;oneatthemouthandoneatRM3.0.SurvivalofsomeyearlingHRPSyearclasseshasdeclinedinthelastthreeyears.The2013populationestimateforyearlingHRPSwas7,935(Rotella2015)andby2016,thenumberofyearlingsstillalivehaddeclinedtoabout4,100HRPSinRPMA1(Rotella,2017).FingerlingswereahighpercentageofsomeHRPSyearclassrecaptures.ApilotstudywasconductedusingShovelnoseSturgeonasasurrogatespeciestoevaluatetheutilityof23mm134kHzPITtagstotracksturgeonmovementinprairiestreams.
INTRODUCTION
TheoriginalPallidSturgeonRecoveryPlan(DryerandSandvol1993)listedthe240-milereachoftheMissouriRiverfromMoronyDamtoFortPeckReservoir(Figure1)asRPMA1.ItisnowpartoftheGreatPlainsmanagementunit(USFWS2014).FortPeckDam,completedinthe1930’s,causedthefirstmajoranthropomorphicchangesonthisreach.FortPeckdamremainsamigrationbarrier,influenceshydrologyandreducesriverinehabitat.Duringthe1950’s,additionalflowandsedimentregimealterationsoccurredduetocompletionofCanyonFerryDamontheMissouriRiverandTiberDamontheMariasRiver.In1996,therewereabout45PallidSturgeoninRPMA1.Thepopulationofsenescentadultfishshowednoevidenceofrecentrecruitment(Gardner1996).MontanaFish,WildlifeandParks(FWP)andtheU.S.FishandWildlifeService(USFWS)initiatedPallidSturgeonrecoveryinRPMA1withthereleaseof732yearlingHRPSin1998.Bysummer2016,80,504fingerlingsand34,086yearlingshadbeenstocked.In2012,yearlingstockingwasreducedtoabout300perfamilybasedonarevisedmanagementplantoincreasegeneticdiversity(Heistetal.2013).ThestockingplanhasbeenevaluatedbysamplingasmanyHRPSaspracticaltomonitorsurvivalrate,growth,movementandhabitatpreference.Mostsamplinghasbeendonewithin50milesoftheRobinsonBridge.Rotella(2015)
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estimatedtheHRPSpopulationat7,935with95%CIof(6231–9630)in2013.By2016,therewereabout4,100HRPSremaininginRPMA1(Rotella,2017).
METHODS
PallidSturgeonsamplingmethodsincludedtrammeldriftnetting,setlinesandtrawling.SeeTewsandGardner(2014)formethoddetails.In2017,trammelnettingconsistedofdriftnettingontheMissouriasfarupstreamasrivermile(RM)2042andonthelowest20milesoftheMariasRiver,targetedbroodstocknettingandtheannualPallidSturgeonassessmentof50trammelnetsetsfromRM1907to1925.3.HRPSwereidentifiedtoyearclassandfamilywith125HzPITtags.AnewPITtagwasinstalled,andageneticsampletakenfromPallidSturgeonwithouttags.PallidSturgeonrelativeconditionfactor(Kn)wasusedtoevaluatecondition(Shumanetal.2011).In2017,78PallidSturgeonweremonitoredwithradiotelemetry.Thesefishhadcontinuouscoveragefrom13fixedremoteradioreceivingstationslocatedthroughoutthestudyarea,including2tributaries(Figure1).Manualboattelemetrytrackingwasalsocompletedatleastmonthlyduringthefieldseason.Bloodwascollectedfromwild,PS-97andsomeotherHRPSforastudyonreproductivestatusconductedbyDr.MollyWebbattheUSFWSBozemanTechCenter.
RESULTS
Thestudyareagenerallyhadflowconditionsnearthemedianin2017,butrun-offoccurredearly(Figure2).In2017,2,136springyearlingsfromGarrisonDamNationalFishHatcheryand413fromtheMilesCityFishHatcherywerestocked.Thesefishwereprogenyfrom4femalesand11males.About50%ofthefishwerestockedatLomaand50%atRobinsonBridge.MostoftheMilesCityhatcheryraisedPallidSturgeon(HRPS)hadfincurl.Stockingrateswerebasedonthemediannumberof329fishstockedpermaleparent.Fingerlingswerenotstockedin2017.GametesfromonewildmaleandtwopreviouslyunrepresentedwildfemalePallidSturgeonfromRPMA1weresuccessfullyincorporatedintothe2017hatcheryprogram.Onefemalediedatthehatcheryafterspawning.Therewere414PallidSturgeoncaptures(Table1),with3wildand12fishfromthe1997-yearclass(PS-97)captured.HRPSfromPS-05throughPS-15werealsocaught.In2017,199geneticssamplesweresubmittedtotheUSFWSatLamarPA.FourofthesefishwerenotmarkedandgeneticstestswerenecessarytoconfirmtheywereHRPS.One299mmlongPS-15diedduringspringsetlining.BloodsamplessenttotheBozemanFishTechnologyCenterforhormoneanalysisincluded;2fromwildfish,15fromPS-97and8fromotheryearclasses.
Springsetlines:In2017,259PallidSturgeonwerecaughtbysetlines(Table1).Standardized
springsetlinesamplinghasbeenconductedintheRobinsonSectionsince2008(Figure3).In2017,PallidSturgeonsetlinecatchrateswerethehighestonrecordandwasthemostcommonspeciescaptured.
FallPallidSturgeontrammelnetsurvey:Therewere103PallidSturgeonsampledduringthe
2017standardizedfalltrammelnetsurveyinthe16-mileRobinsonBridgetrendarea(Table2).Samplingconditionswereexcellent.PallidSturgeonCPUEwasthesecondhighestonrecordandwasmuchhigherthanseenforthepastthreeyears.ShovelnoseSturgeoncaptureratesincreasedtothehighestobservedsince2013andwerenearaverage(Figure4,Table2).
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Figure1.MapofRPMA1,theMissouriRiver,aboveFortPeck.
Figure2.FlowsattheFredRobinsonBridgein2017comparedwithlongtermmedian.DatafromtheUSGSwebinterfaceNovember30,2017.
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Size,yearclassstructureandsurvival:From2005–2009therewereover4,000yearlingsstockedannually,butHRPScatchratehasnotbeenconsistentwithstockingrates(Figure5).PS-09hasconsistentlybeenthestrongestyearclassandhascomprisedmorethan20%oftheHRPScatchsince2013.Incontrast,thePS-07classhadthehighestyearlingstockingdensitybuthasconsistentlyrepresentedlessthan10%ofthefishcapturedCatchratesofmostrecentyearclassesappeartoberelatedtostockingdensities.AverageHRPSforklengthfordifferentstockingcohortsdemonstratestheslowgrowthofallbutthePS-97ageclass(Figure6).Assessmentoftheparameters,suchasstockingdensity,thatcauseslowgrowthwouldbenefitrecovery.Despiteslowgrowth,HRPSofallyearclasseshavemaintainedandevenimprovedtheirconditioninrecentyears.In2017,Knofallsizeclasses,exceeded0.9(Figure7).SurvivalofsomeyearlingHRPSyearclasseshasdeclinedinthelastthreeyears.The2013populationestimateforHRPSyearlingswas7,935(Rotella2015)andby2016,thenumberofyearlingsstillalivehaddeclinedtoabout4,100HRPSinRPMA1(Rotella2017).ThisnumberisanunderestimateofthetotalHRPSpopulation;fingerlingswerenotincluded.Thenumberoffingerlingscapturedhasincreasedsubstantiallyinrecentyears(Table3)andfingerlingrecapturesareahighpercentageofsomeHRPSyearclasses(Table3,Figure5).Modelsusedinfuturesurvivalestimatesshouldincludethesefish.
RadioTelemetry/Movements:In2017,78PallidSturgeon,including67PS-97,2PS-05,1PS-09
and8wildfishweremonitoredwithradiotelemetryinRPMA1.ManualboattrackingwascompletedatleastmonthlyfromApril–October;1931boattrackingmileswereloggedin2017for618PallidSturgeonrelocations,including135exactlocations(Tewsetal.2018).Atotalof1,141PallidSturgeonrelocationswererecordedat11ofthe14remotestations.TrackinghistoryofthreewildfemalePallidSturgeonmonitoredfrom2016–2017isshowninFigure8.TwowildfemalesmademigrationsfromRobinsonBridgetoaboveCoalBanksduringnon-spawningyears.Thethirdremainedwithin30milesofRobinsonBridge.ThewildmalePallidSturgeoninRPMA1migratedowntotheRobinsonBridge/PowerPlantareainlateMay,stayforapproximatelyonemonthandthenreturntotheirhomelocationsatRM2010,1988,1970and1955(Figure8).SexuallymaturePS-97appeartomovefrequentlywithin20milesofRobinsonbridgeduringthespawningseason,whileimmaturePS-97hadtwotypicalpatterns;onewithmovementstypicallywithin30milesofRobinsonBridgeandonewithlongdistancemigrationstoanewlong-termterritory(Figure9).ForPS-97,31%wererelocatedupstreamofJudithLanding(RM1984).PercentagesweresimilarforwildPallidSturgeon.Oneradio-taggedmaturemalePS-97wasrecordedupstreamofFortBenton.TwootherHRPSwerecapturedabovetheMariasRiver;includingonenearthemouthofHighwoodCreek.Tworadio-taggedPS-97wererecordedintheMariasRiverin2017;oneatthemouthandoneatRM3.0.ThreePallidSturgeonwerecaughtintheMariasRiver.OnePS-07andonePS-08werecaughton6/14atRM7.6andaPS-13wascaughton7/6atRM0.6.Allthreefishwerestockedasfingerlings.TwowerestockedatRobinsonBridgeandthestockinglocationofthirdfingerlingisnotknown.ThePS-07waspreviouslycaughtatRM1918in2012andthePS-13waspreviouslycaughtatRM1906and1910in2015.Itissurprisingthatthesefishmigratedsofarupstreamatanearlyage.
PilotPITtagStudy:HDX23mm134.2kHztagswereinstalledintheperitonealcavityofShovelnoseSturgeon,BlueSuckersandseveralotherspeciesin2016and2017toevaluatefishmovementsintotheLowerMariasRiver.ShovelnoseSturgeonwereusedasasurrogateforPallidSturgeonandwerethefocusofthestudy.OnApril20,2017,aPITtagarraywithtwoantennaewasinstalledatRM1.0ontheMariasRiver.FromMay9–November9therewere608“hits”onthePITtag
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stationfrom260differentfish.OnehundredandninefishrecordedatthestationwereoriginallytaggednearCoalBanksand143weretaggedintheMarias.Atotalof22.4%ofthetaggedCoalBanksShovelnoseSturgeonand54.3%oftheShovelnoseSturgeontaggedintheMariaswererecordedatMariasRM1.0.TagRetentionwithperitonealinstallationwasexcellentformatureShovelnoseSturgeon.OnehundredpercentoftheShovelnoseSturgeonwithexternaltagsnettedinSpring2017,thatwerePITtaggedin2016(N=5),hadretainedtheirPITtags;notaglosswasdocumented.In2017,datawasonlycollectedatthelonger,northantenna,duetoitsinterferencewiththesouthantenna.ThereweresomeinitialreadingissueswiththePITArrayandthestationwasnotrecordingateitherantennafromMay24–June13,2017.However,thepercentageoffishrecorded,despiteonlypartialcoverageoftheMariasisimpressive,consideringthatfishpassageinthethalweg(southantennae)wasnotmonitored.Thereturnrateofonly50%offishtaggedintheMariasRiverwaslikelyduetothispartialcoverage.Readrangeoftheantennawasusuallygood;forexample,itwas15inchesonJuly21.
RECOMMENDATIONS
1. ContinuethestockingevaluationofHRPSincorporatingmultiplesamplingmethods,includingsetlinesandfalltrammelnetting.
2. ContinuetoevaluateHRPSsurvivalusingupdatedmodelsthatincludefingerlings.3. IncreasePallidSturgeonsamplingupstreamofthecurrentfocusarea(RM1930).4. UseradiotelemetryinconjunctionwithhormoneanalysistodeterminelocationofPallidSturgeon
spawningareas.Additionalfundingisnecessarytofindspawningareas.AWesternAreaPowerfundedMontanaStateUniversityMaster’scandidatewillfocusonthisworkstartingin2018.
5. ConsiderachangeofPITtagfrequencytothecurrentstandardof134.2kHz.6. Evaluateperitonealinsertionof23mmPITtagsinPallidSturgeontoenablemonitoringofHRPS
movements.
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Figure3.CatchratesofcommonspeciescapturedduringspringsetlininginRPMA1,2008–2016.
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Table1.NumberofPallidSturgeoncaptured,bymethod,intheMiddleMissouriRiver,MTaboveFortPeckReservoir2017.
Method
YearClass Setline Other Trammel Total
1997 2
10 12
2005 5 1 5 11
2006 16 5 6 27
2007 13 2 4 19
2008 27 8 12 47
2009 102 7 21 130
2010 25 4 6 35
2012 5
4 9
2013 16 1 7 24
2014 17
14 31
2015 31
19 50
2016
1 14 15
Unknown
1 1
Wild
3 3
Total 259 29 126 414
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Table2.SamplingstatisticsfortheannualPallidSturgeonassessment,nearRobinsonBridge,intheMiddleMissouriRiver,MT,1996-2017,comparedwithPallidSturgeoncapturedbyFWP2008–2017.
Year
(1996-
2007) 2008 2009 2010 2011 2012
2013
2014 2015
2016 2017
PallidSturgeon
#Sampled 6.8 28 42 39 39 99 106 14 67 61 103
#Wild 0.6 0 0 0 0 0 0 0 0 0 0
#HRPS 6.0 28 42 25 39 99 106 14 67 61 103
Mean#/drift 0.13 0.56 0.82 0.50 0.78 1.98 2.12 0.21 1.34 1.22 2.06
All(RPMA1) 146 271 347 302 334 451 217 257 229 414
ShovelnoseSturgeon
#sampled 210 222 227 173 125 226 253 80 108 155 181
Averageweight(g) 1477 1693 1612 1838 1924 1884 1871 1862 1842 1797 1904
number/drift 4.2 4.4 4.4 3.5 2.5 4.5 5.1 1.25 2.2 3.1 3.6
Driftnetsamplinginformation(mean)
Drifttime(min) 6.8 6.8 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0 7.0
#ofdrifts 50 50 50 50 50 50 64 50 50 50
Driftdistance(m) 262 262 303 291 272 215 278 376 320 284 354
Depth(m) 1.9 1.6 1.7 2.0 2.4 2.0 1.7 2.7 1.8 1.9 1.8
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Table3.PercentofHRPSknownfingerlingscomparedtoknownyearlings,capturedbyyearandbyyearclassforfishcaptured2005–2017.
CaptureType N%Fingerlingsby
year
Captureyear
2006 3 3.7
2007 3 1.8
2008 1 0.7
2009 4 1.5
2010 23 6.8
2011 24 8.3
2012 29 9.0
2013 53 13.1
2014 32 17.0
2015 47 16.2
2016 35 13.0
2017 91 23.9
Total 345
Yearclass
2005 15 2.8
2006 0 0
2007 23 7.7
2008 60 13.0
2009 133 24.3
2010 53 39.5
2012 0 0.0
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2013 9 19.6
2014 13 25.4
2015 36 53.7
2016 3 15.4
Total 345
Figure4.PallidSturgeonandShovelnoseSturgeoncatchratetrendforfalltrammelnettingpopulationassessmentsurveysconductedintheMiddleMissouriRiver,1996–2016.
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Figure5.Percentofcatchbyyearclassin2013–2017comparedwithtotalnumberofyearlingfishstockedbyyearclass,showingyearclasseswithhighfingerlingnumbers.
Figure6.MeanforklengthofknownageHRPSthroughage12.PS-97averaged1052mmforklengthatAge20in2017.
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Figure7.PallidSturgeonconditionbysizeclassinRPMA1.Stock330-629mm;Quality630–839mm;Preferred840–1039mm;Memorable1040–1269mm;Trophy≥1270mm.Trophyfishareallwild,MemorablearegenerallyPS-97;SizeclassesandKnformulafromShumanetal.2011.
Figure8.MovementsofwildPallidSturgeoninRPMA1forfishmonitoredin2016and2017.
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Figure9.Movementpatternsofnon-reproductivePS-97taggedin2012and2013,comparedwithPS-97thatwerematureby2017.
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REFERENCES
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Gardner,W.M.1996.MissouriRiverpallidsturgeoninventory.MontanaFishWildlifeandParks.Fed.AidtoFishandWildlifeRest.Proj.F-78-R-2.Helena.
Heist,E.and4others.2013.PopulationGeneticsManagementplanforpallidsturgeonintheUpperMissouriBasin.ForWesternAreaPower.
Rotella,J.2015.UpperBasinPallidSturgeonSurvivalEstimationProject–2015UpdateReporttoUpperBasinPallidSturgeonWorkgroup.Revised2015.
Rotella,J.2017.UpperBasinPallidSturgeonSurvivalEstimationProject–2017UpdateReporttoUpperBasinPallidSturgeonWorkgroup.Revised2017.
Schuman,D.A.and11others.2011.Pallidsturgeonstructure,condition,andgrowthintheMissouriRiverBasin.JournalofAppliedIchthyology27:269–281.
Tews,A.andW.M.Gardner.2014.MiddleMissouriFisheriesEvaluations.2007–2013Report.MontanaFishWildlifeandParks.FederalAidF113/R7-R13.
TewsA.,M.SchilzandR.Beattie.2018.MissouriRiverRadioTelemetryandUSBR2016and2017ProgressReport.ForFWP,USBRandNorthwesternEnergyCompany.
ACKNOWLEDGEMENTS
NateBeckman,KatieVivian,GrantGrisak,JasonMullanandMarySchvetzofMFWPandSteveLeathe(NWE)assistedwithfieldwork.ThanksalsotoDr.MollyWebbandherlabforevaluatinghormonelevelsinsturgeonbloodandevaluatingspawningstatus.SpecialfundingforthisprojectwasprovidedbytheUSBRandNWE.AdditionalfundingwasprovidedbyMFWP,WesternAreaPowerAuthorityandtheUSFWS.
34
2017AnnualReport
PallidSturgeonPopulationAssessmentandAssociatedFishCommunityMonitoringfortheMissouriRiver:Segment2
PreparedfortheU.S.ArmyCorpsofEngineers–MissouriRiverRecoveryProgram
By:
JohnHunzikerandTylerHaddix
MontanaFish,Wildlife&Parks
POBOX165
FortPeck,MT59223
March2018
EXECUTIVESUMMARY
The2017fieldseasonmarkedthe12thconsecutivesamplingyearforPallidSturgeonPopulationAssessmentcrewsinSegment2oftheMissouriRiver.Althoughthiswasthe12thyearofsampling,itwasalsothesecondconsecutiveyearofareductioninsamplinggears.Neithertheottertrawlormini-fykenetwasusedinsamplingduringthe2016or2017fieldseason.Samplingeffortswiththetwostandard
35
gears,trammelnetandtrotline,ledtothecaptureof31pallidsturgeon,allofwhichwereofhatcheryorigin.
Atotalof12randomlyselectedriverbendsweresampledinSegment2during2017.All12bendsweresampledwithtrammelnetsduringbothsturgeonandfishcommunityseasons.Comparatively,trotlineswereusedtosampleeachbendonce;withhalfofthebendssampledduringsturgeonseasonandtheotherhalfsampledduringthefishcommunityseason.Atotalof205trammelnetsweredriftedthroughoutSegment2in2017,whichaccountedfor48.2kmofsampling.Additionally,usingthestandardsamplingmethodofeighttrotlinesperbend,atotalof96trotlinesweredeployed,totaling1,960nightcrawler-baitedhooknights.
Atotalof31pallidsturgeonwerecapturedinSegment2duringthe2017fieldseason,allofwhichwereofhatcheryorigin.Temporally,morepallidsturgeonwerecapturedduringsturgeonseason(n=17),thanfishcommunityseason(n=14).Trotlinewasthemostsuccessfulgearatcapturingpallidsturgeon,resultingin20observations,whiletrammelnetdetectedanadditional11individuals.Pallidsturgeonweredetectedinfiveofthe12randomlyselectedtrammelnetbends.Incomparison,pallidsturgeonwerecapturedinsixofthe12randomlyselectedtrotlinebends.Additionally,samplingeventsatlocalizedspotsonceagainbolsteredtotalcaptures,with23%ofthetotalcomingfromasinglebendduringfishcommunityseason.
TrammelnetCPUEforthe2017fieldseasonthroughoutSegment2wastabulatedat0.02fish/100mforallthreeseasonalmetrics(sturgeon,fishcommunity,andcombinedseasons).TrotlinecapturesledtoCPUEsof0.26fish/20hooksand0.17fish/20hooksforthesturgeonandfishcommunityseasons,respectively.Acombined-seasonCPUEwasestimatedat0.21fish/20hooknight.
PallidsturgeonhandledinSegment2duringthe2017fieldseasonaveraged471mminforklengthandaveraged440ginweight.Lengthsrangedfrom372mmto957mmforklength.Trammelnetscapturedonaveragelargerindividuals(513mm)thandidtrotlines(448mm).Thevastmajority(94%)ofpallidsturgeoncapturedin2017fellintothestocksizecategory,whiletheother6%(n=2),wereinthepreferredsizedesignation.Nomajorvariationsinrelativeconditionwereobservedbetweenthetwosizedesignations.
Ofthe31pallidsturgeonsampledinSegment2duringthe2017fieldseason,allbutonewereofaknownyearclass.Yearclassesinrankofabundancewere;2006(n=8),2008(n=7),2009(n=6),2010(n=4)and1997,2003,2007,2015,and2016wereallrepresentedbyoneindividual.Inregardtostockinglocation,27ofthe31pallidsturgeoncapturedthroughoutSegment2duringthe2017fieldseasonweretiedtoaknownstockinglocation.Inrelationtostocking-river,morepallidsturgeonoriginatedfromtheMissouriRiver(n=17)thanoriginatedfromtheYellowstoneRiver(n=10).Stockinglocationinrankofabundancewere;WolfPoint(n=9),Culbertson(n=8),Fallon(n=4),Intake(n=3),Sidney(n=2),andForsyth(n=1).
ShovelnosesturgeonobservationsinSegment2oftheMissouriRiverwereonceagainacommonoccurrenceduringthe2017fieldseason.Atotalof536shovelnosesturgeonwerecapturedin2017,whichwasmorethananyotherspecies.Seasonally,aslightlyhigherproportionofshovelnose
36
sturgeon(n=276)werecapturedduringsturgeonseasonwhencomparedtofishcommunityseason(n=260).Inrelationtogears,trammelnetscapturedmoreshovelnosesturgeon(n=363)thandidtrotlines(n=173).
TrammelnetCPUE,regardingshovelnosesturgeonofthequalityorgreatersizeclass,wasrecordedas0.68fish/100mforboththesturgeonandfishcommunityseasons,respectively.IdenticalseasonalCPUEsinturnledtoacalculatedcombined-seasonCPUEof0.68fish/100m.TheobservedtrotlineCPUEwastabulatedat1.96fish/20hooksand1.73fish/20hooksforthesturgeonandfishcommunityseasons,respectively.Thecombined-seasonCPUEwasthencalculatedtobe1.84fish/20hooks.DuetothesizestructureoftheshovelnosesturgeonpopulationsampledinSegment2,trammelnetandtrotlineCPUEremainedverylowforthestockandsub-stockcategories.
Theshovelnosesturgeonobservedduringthe2017fieldseasonthroughoutSegment2averaged608mminforklengthand898ginweight.WiththerarityofsmallersizeclassesofshovelnosesturgeonresidinginSegment2,observedaveragelengthhasremainednearlyidenticalovertime.Therelativeweightforboththestockandqualitysizeclassesofshovelnosesturgeonremainshighlyvariableduetolowsamplesize.Conversely,therelativeweightforthepreferredandmemorable/trophysizeclassofshovelnosesturgeoninSegment2hasremainedmuchmorestableandcomparable
Atotalof10bluesuckerswerecapturedinSegment2duringthe2017fieldseason;allofwhichwerecapturedviatrammelnetduringrandomdeployments.Temporally,morebluesuckerswerecapturedduringsturgeonseason(n=6),whencomparedtofishcommunityseason(n=4).ReportedtrammelnetCPUEof0.03fish/100mand0.02fish/100mforthesturgeonandfishcommunityseasons,respectively,ledtoacombined-seasonCPUEof0.02fish/100m.Thebluesuckersobservedduringthe2017fieldseasonaveraged648mmintotallengthand2,801ginweight.IthasremainedtypicalinSegment2thatbluesuckercatchesaredominatedbylarge,adultindividuals.
Atotalof125saugerwerecapturedthroughoutSegment2duringthe2017fieldseason.Nearlyallsaugerwereobservedviatrammelnet,sansaloneindividualrepresentedbyatrotlinecapture.Moresaugerwerecapturedduringsturgeonseason(n=103),thanduringfishcommunityseason(n=22).Thecombined-seasontrammelnetCPUEforwasrecordedat0.25fish/100m.Seasonally,CPUEwastabulatedat0.42fish/100mand0.09fish/100mforthesturgeonandfishcommunityseasons,respectively.Thesaugercapturedin2017seasonaveraged350mmintotallengthand327ginweight,witharangefrom222mmto518mm.
Withthesuspensionoftheottertrawlandmini-fykenetassamplinggearsforthe2016and2017fieldseasons,noneofthesmall-bodiedtargetspecies(sturgeonandsicklefinchubs,Hybognathusspp.,andsandshiner)wererepresentedinthecatchdataforSegment2.
37
2017MissouriRiverSamplingfromtheYellowstoneConfluencetoLakeSakakawea
USFWSBismarck,ND
TheMissouriRiverbelowtheconfluenceoftheYellowstoneRiverisahighlydynamicsystemandfeaturesadiverseassemblageofhabitatsthattypifythehistoricconditionsoftheriver.TheinfluenceoftheYellowstoneRiverandtheseasonalfluctuationsinthehydrograph,includingtheimmensesedimentload,greatlyinfluencethefishcommunity,includingthepallidsturgeon.TheelevationofLakeSakakaweaalsoinfluencesthelowerportionofsegment4.TheUSFWSMissouriRiverFishandWildlifeConservationOfficeinBismarckbegansamplingthetwelverandomriverbendsofsegment4onthe17thofAprilandcompletedsamplingonthe14thofOctober.Over71,000metersweredriftedwithtrammelnetswhichincludednearly42,000metersduringatargetedsamplingeffort.Ottertrawlsweretowedonly4,361metersduringthesturgeonseasonduetohighflowsfromtheYellowstoneRiverinMaywhichresultedinunsafesamplingconditions.26,366metersweretrawledduringthefishcommunityseason.Additionally,minifykenetsweresetin12bendsduringthefishcommunityseasonandtrotlinesweredeployedin12randombendsduringfishcommunityseason.Pallidsturgeon(Scaphrynchusalbus)istheprimarytargetofthissamplingeffort.Onehundredseventyfivehatcheryreleasedandthreewildadultpallidsturgeonwerecapturedinsegment4in2017.Thiswaslessthan2010(N=724),2014(N=440),2015(N=435)and2016(N=180)butwasthefifthmostcapturedinthirteenyearsofsampling.Followingstandardprotocolswecaptured47pallidsturgeonintwelverandombendswithtrammelnets.Trotlinescaught64hatcheryreleasedpallidsturgeonwhile14weresampledwiththeottertrawl.Additionally,26hatcheryreleasedpallidsturgeonwerecapturedduringathreedaytargetedsamplingeffortwithtrammelnetsinthelowersectionofsegment4.Pallidsturgeonfromall18yearclassesthathavebeenstockedinRPMA2werecollectedin2017.Pallidsturgeonfrom9stockinglocationsusedwithintheMissouriandYellowstoneRiversabovetheconfluenceweresampledwiththemajority(58%)originatingfromYellowstonestockingsites.Relativeconditionfactorforallpallidsturgeoncapturedduringthiseffortrangedfrom0.95to1.02.Growthratesforrecapturedjuvenilesturgeonrangedfrom0.06to0.313mm/daywithyoungersturgeonshowingahighergrowthrate(Table4).Atotalof418shovelnosesturgeonS.platorynchusweresampledduringthe2017samplingseasoninsegment4.Themajorityweresampledintrammelnets(N=319)followedbytheottertrawl(N=80)andtrotlines(N=19).Thirtyage-0shovelnosesturgeonwerecapturedin2017.Qualityandabovesizeclassfishcontinuedtoaccountforthemajorityshovelnosesturgeonsampled.In2017,sixoftheeightnativeMissouriRiverspeciesthatweretargetedforthisassessmentweresampled.SturgeonchubMacrohybopsisgelidaweresampledinottertrawls(N=119).Atotalof111sicklefinchubsM.meekiwerecollectedinsegment4withallsicklefinchubsbeingcapturedintheottertrawl.Westernsilveryminnows,Hybognathusargyritis,werecapturedduringthefishcommunityseasoninmini-fykenets(N=60)andtheottertrawl(N=6).Atotalof17bluesuckersCycleptuselongateswerecollectedintrammelnets(N=16)andtheottertrawl(N=1).Noyoungoftheyearbluesuckerswerecollected.SaugerSandercanadensewerecapturedinallgearsduringbothseasons.Trammelnetscapturedthemostsauger(N=155),followedbytheottertrawl(N=20)andmini-fykenets(N=19).ShoalchubsM.aestivalisandsandshinerNotroposstramineusweretheonlytargetednativespeciesnotcapturedinanygear.Sandshinerswerecollectedin2005,2006,2007,2008,2009
38
and2013.Shoalchubshavenotbeensampledinsegment4in13yearsofsampling.Atotalof22,380fishrepresenting30speciesweresampledinsegment4oftheMissouriRiverduring2017.
39
LowerYellowstoneRiverPallidSturgeonProgressReport
Periodcovered:January2017–December2017
Author:MathewRugg
LowerYellowstoneRiverBiologist
MontanaFish,Wildlife&Parks
Glendive,MT59330
(218)205-6132
email:[email protected]
MultiplePallidSturgeonresearchandrecoveryactivitiesoccurredontheYellowstone
Riverduring2017including:telemetrytrackingofadultsandjuvenilestoassessspawning,
habitatuse,andpassagelimitations,andjuvenilesamplingtocontinuehistoricaltrenddataand
aidinthecomputationofsurvivalestimatesofhatcherystockedindividuals.
YellowstoneRiverdailywaterdischargeduring2017nearSidney,MTwasatorabove
thehistoricmediandailydischarge(Figure1).Thespring-pulseonsetbeganearly,inFebruary,
andremainedabovehistoricmedianflowsthroughthemid-Junepeak(57,300cfs)largelydueto
increasedflowsoutoftheBighornRiver.SpringdischargeoutoftheBighornRiverin2017was
2-4timesgreaterthanthehistoricaveragedischarge,anddischargeremainedabovehistorical
averagesthroughouttheentiretyof2017.YellowstoneRiverdischargewasalsogreatly
influencedbytheabundanceofwatercomingfromtheBighornRiverthroughout2017.
PALLIDSTURGEONPOPULATIONMONITORING
Annualtargetedmonitoringofhatchery-rearedPallidSturgeonwasconductedusing
driftedtrammelnets(6’X100’;1”barmesh)fromlateJulytolateSeptember.Thedataderived
fromtheseeffortsareusedinmultiplewaysincludingtheestimatingsurvivalofstockedPallid
Sturgeon.Survivalestimatesutilizingthesedataandbydatacollectedbyotherfieldcrewswere
originallygeneratedin2009(Hadley&Rotella2009)andhavebeenupdatedperiodicallywith
40
capturehistoriesfromsubsequentyears(Rotella2010,Rotella2012,Rotella2015,Rotella
2017).BluffpoolhabitatsbetweenIntakeDiversionDam(Intake)andtheconfluencewiththe
MissouriRiverhavebeentraditionalfocalpointsofourefforts.However,arecentinfluxof
juvenilePallidSturgeonequippedwithradiotransmittersandmanyrelocationsoutsideofthe
traditionalbluffpoolhabitatspromptedtheexpansionof2017samplingintoadiversityof
habitatsincludingrifflesandruns.
RESULTS
In2017,528trammelnetsweredeployed,yieldingatotalnettingeffortof
approximately120hoursand320kmdrifted.Ninety-OnePallidSturgeonwerecaptured
ranginginsizefrom329mmto1371mm.Lengthgroupsfrom300mmthrough1000mmwere
allwellrepresented,andseveralindividualslargerthan1200mmwerealsocaptured(Figure2).
Incrementalrelativestockdensity(RSD)includedthepresenceofmorepreferredsizeandlarger
PallidSturgeonthananyofthepast5years(Figure3).PallidSturgeoncatchratebyhour(0.71
fish/hr)andbydistance(0.29fish/km)remainedlowcomparedtothe10-yearaverage,butthe
catchtrendcontinuestocloselymatchthestockingtrend(Figure4).Thatis,thehighestcatch
ratesinthepast10yearshaveallcoincidedwithrelativelyhighnumbersofPallidSturgeon
stocked(Figure4).Reducedcatchratesinrecentyearsarepotentiallyduetoachangein
stockingstrategythathasdrasticallydecreasedthenumberofhatchery-reared,juvenilePallid
Sturgeonstockedinanattempttoalleviatepotentialcarry-capacityconcerns.Conditionfactor
(Kn)ofallPallidSturgeonsizecategories,excepttrophy-sized,remainedatorslightlybelow1.0
(Figure5).Trophy-sizedPallidSturgeonconditionfactorhasbeenatorwellabove1.0;
however,mosttrophy-sizedindividualsthatwerecapturedwereinspawningconditionand
theirconditionfactorwaspositivelyinfluencedbythepresenceoffullymaturegonads.
Forty-twogeneticsamplesand35bloodsamplesweretaken,and37radiotransmitters
wereimplantedintoPallidSturgeonduring2017.Geneticsampleswillbeusedtodetermine
theoriginofunmarkedindividuals(e.g.hatcheryorwildproduced)aswellastoassign
parentagetothosewithoutindividuallyuniquemarkings.Plasmaextractedfrombloodsamples
willbeanalyzedforsexsteroidstoestimatematurity.Radiotransmitterswillbeusedto
subsequentlytrackandpotentiallyrecapturePallidSturgeontoassessmaturation,habitatuse,
spawningmigrations,dampassage,etc.
41
TARGETEDPALLIDSTURGEONMONITORINGUPSTREAMOFINTAKE
Monitoringofhatchery-rearedPallidSturgeonupstreamofIntakebeganin2011and
hasbeenrepeatedannuallythereafter.Previoustelemetryinvestigationssuggestedsuitable
PallidSturgeonhabitatwasavailableupstreamofIntake,andthefrequencyandgeographic
rangeofPallidSturgeoncapturesupstreamofIntakehasincreasedinrecentyears.Trammel
nets(6’x100’;1”barmesh)weredriftedprimarilyinbluffpoolsandlongrunsbetweenthe
PowderRiverConfluenceandStipekFishingAccessSite.
RESULTS
SixdaysofnettingeffortaboveIntakeresultedin75totaltrammelnetdriftsthat
equatedto21.0nettinghoursand60.4kmdrifted.Theeffortresultedinthecaptureof331
ShovelnoseSturgeonand8PallidSturgeon.TheresultantPallidSturgeoncatchrateabove
Intakeduringthesturgeon-targetedeffortwas0.38fish/hrand0.13fish/km,whileShovelnose
Sturgeoncatchratewas15.8fish/hrand5.5fish/km(Figure6).Comparatively,PallidSturgeon
catchrates(0.78fish/hr;0.32fish/km)andShovelnoseSturgeoncatchrates(37.7fish/hr;15.7
fish/km)downstreamofIntakeweregreaterthanthoseupstream(Figure6).PallidSturgeon
capturedupstreamofIntakerangedinsizefrom394mmto915mm;however,thesize
distributionwasheavilyskewedtowards300and400mmlengthgroups(Figure7).
MIGRATIONPATHWAYS,HABITATUSE,ANDREPRODUCTIONOFPALLIDSTURGEON
ThiswasyearsixofacollaborativeeffortbetweenU.S.GeologicalSurvey(USGS)and
MontanaFish,Wildlife&Parks(FWP)investigatingandassessingmigrationpathways,habitat
useandreproductionofPallidSturgeonintheYellowstoneRiver.Theresearchneedstemsfrom
recoveryeffortstoattainpassageatIntake,wherelimiteddataareavailableregarding
migrationsandreproductionofPallidSturgeon.Additionally,thedatawillbeutilizedtoderive
comparisonofPallidSturgeonmigrationsinthenaturalYellowstoneRivertothoseofthelower
channelizedMissouriRiver.EffortstomonitorPallidSturgeonreproductionintheYellowstone
Riveriswarrantedtoexaminetemporalperiodicityofspawningeventsinrelationto
environmentalconditionsandtoquantifyspecifichabitatonspawninggroundsinanatural
system.Objectivesoftheresearchwere1)examinemigrationpathways,timing,extent,main
42
andsidechanneluseandapproachtoIntake2)analyzehabitatuse-depthsandvelocities3)
documentspawningtiming,habitatandlocation4)documentthehatchofembryos.
BeginninginearlyApril,manualtrackingrunswereconductedfortelemeteredadult
PallidSturgeonontheYellowstoneRiveratintervalsrangingfromonceperweektoonceper
day.Trackingdatawillbesupplementedwithanetworkoftelemetrygroundstationsthat
coverstheYellowstoneRiverfromForsyth,MTtotheconfluencewiththeMissouriRiver,and
theMissouriRiverfromtheMilkRivertotheconfluencewiththeYellowstoneRiver(Figure8).
AdetailedreportofallfindingswillbeproducedbyUSGSbySpring2018.
ADDITIONALMISCELANNEOUSPALLIDSTURGEONACTIVITIES
• CrewsassistedwithPallidSturgeonBroodstockcollectioninthelowermostreachesof
theYellowstoneRivernearitsconfluencewiththeMissouriRiver.Crewscapturedtwo
wild,adultmalesthatwassentintothehatcherysystemforpropagation.
• Crewsattendedanoil-spillpreparationworkshopheldbyUSFWSandUSGSthat
includedshortinstructionalpresentationsonproceduralpracticesthatcouldbe
implementedshouldanoil-spilloccurinPallidSturgeonrange.Theworkshopalso
includedatwo-daysamplingeffortdirectedatcollectingwholeShovelnoseSturgeonto
beeuthanizedandbloodsamplesfromPallidSturgeon.Tissueandbloodsampleswill
beanalyzedbyUSFWSandUSGStoprovideabaselineoccurrenceofhydrocarbonsin
sturgeonspeciesintheYellowstone-MissouriRiversystem.FWPRegion7crews
collected7bloodsamplesfromPallidSturgeonforthiseffort.
• BureauofReclamation(BOR)initiatedPallidSturgeontranslocationeffortsin2017as
dictatedbytheIntakeBiologicalOpinion.FWPcrewstrainedBORstaffontheprotocols
forlocating,netting,andassessingadultPallidSturgeon.
43
LiteratureCitedHadley,G.L.,andRotella,J.J.2009.UpperBasinPallidSturgeonPopulationEstimationProject.
FinalReportsubmittedtoUpperBasinPallidSturgeonRecoveryWorkgroup.Rotella,J.J.2010.UpperBasinPallidSturgeonSurvivalEstimationProject–2010Update.Final
ReportsubmittedtoUpperBasinPallidSturgeonRecoveryWorkgroup.Rotella,J.J.2012.UpperBasinPallidSturgeonSurvivalEstimationProject–2012Update.Final
ReportsubmittedtoUpperBasinPallidSturgeonRecoveryWorkgroup.Rotella,J.J.2015.UpperBasinPallidSturgeonSurvivalEstimationProject–2015Update.Final
ReportsubmittedtoUpperBasinPallidSturgeonRecoveryWorkgroup.Rotella,J.J.2017.UpperBasinPallidSturgeonSurvivalEstimationProject–2017Update.Final
ReportsubmittedtoUpperBasinPallidSturgeonRecoveryWorkgroup.Shuman,D.A.,D.W.Willis,andS.C.Krentz.2006.ApplicationofaLength-Categorization
SystemforPallidSturgeon(Scaphirhynchusalbus).JournalofFreshwaterEcology.Volume21,Number1.
Shuman,D.A.,R.A.Klumb,R.H.Wilson,M.E.Jaeger,T.Haddix,W.M.Gardner,W.J.Doyle,P.T.
Horner,M.Ruggles,K.D.Steffenson,S.StukelandG.A.Wanner.2011.Pallidsturgeonsizestructure,condition,andgrowthintheMissouriRiverBasin.JournalofAppliedIchthyology(27),269-281.
44
Figure 1. Yellowstone River daily mean discharge for 2017 and historic daily median discharge near Sidney, Montana (USGS gaging station 06329500). Data provided by USGS.
45
100-mm length group
0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300
frequ
ency
0
5
10
15
20
25
30
Downstream of IntakeUpstream of Intake
Figure 2. Length frequency histogram of Pallid Sturgeon captured downstream (black bars) and upstream (grey bars) of Intake Diversion Dam in the Yellowstone River during 2017 fall sampling efforts.
46
Year
2013 2014 2015 2016 2017
RS
D
0
20
40
60
80
100
S-Q Q-P P-M M-T T
Figure 3. Incremental relative stock density (RSD) for pallid sturgeon captured during fall population monitoring efforts 2013-2017 in the Yellowstone River. Length categories determined using the methods proposed by Shuman et al. (2006).
47
Capture Year
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017
Num
ber s
tock
ed (y
earli
ng e
quiv
alen
t)
0
5000
10000
15000
20000
25000
30000
CP
UE
(pal
lid/k
m)
0
2
4
6
8
10
CP
UE
(pal
lid/h
r)
0
1
2
3
4
5
pallids stockedpallid/kmpallids/hr
Figure 4. Yellowstone River catch per unit effort (fish per kilometer and fish per hour) and stocking history for Pallid Sturgeon in the Yellowstone River and Missouri River below Ft. Peck Dam since 2006. Note: 2017 stocking numbers not included in this figure.
48
Year
2013 2014 2015 2016 2017
Kn
0.8
1.0
1.2
1.4
Stock-QualityQuality-Preferred
Year
2013 2014 2015 2016 2017
Kn
0.8
1.0
1.2
1.4Preferred-MemorableMemorable-TrophyTrophy
Figure 5. Relative condition factor (Kn) for all Pallid Sturgeon captured with all gear by incremental relative stock density (RSD) length category from 2013-2017 in the Yellowstone River. Length categories determined using the methods proposed by Shuman et al. (2006). Relative condition factor was calculated using the equation in Shuman et al. (2011).
49
Location Relative to Intake Diversion Dam
Downstream Upstream
CP
UE
(fis
h/km
)
0
2
4
6
8
10
12
14
16
18
PallidShovelnose
Figure 6. Relative abundance of Pallid Sturgeon and Shovelnose Sturgeon captured on the Yellowstone River upstream and downstream of Intake Diversion Dam in 2017.
50
100-mm length group
300 400 500 600 700 800 900
frequ
ency
0
1
2
3
4
5
6
Figure 7. Length frequency histogram of Pallid Sturgeon captured upstream of Intake Diversion in the Yellowstone River during 2017 fall sampling efforts.
51
Figure 8. Locations of ground-based, logging telemetry stations deployed on the Yellowstone River (Cartersville, Miles City, Fallon, Gibbs, Hoff, Side Channel Upstream, Intake Dam, Side Channel downstream, Rock, Seven Sisters, Fairview, Yellowstone confluence) and Missouri River (Milk River confluence, Wolf Point, Culbertson, Missouri confluence), and tributaries (Powder River, Milk River) during 2017.
52
2017AnnualReport
PallidSturgeonPopulationAssessmentandAssociatedFishCommunityMonitoringfortheMissouriRiver:Segments5and6
LandonL.Pierce,DanielA.James,andDylanA.Turner
UnitedStatesFishandWildlifeService
GreatPlainsFishandWildlifeConservationOffice
FundedbyU.S.ArmyCorpsofEngineers–MissouriRiverRecoveryProgram
Summary
PallidsturgeonScaphirhynchusalbusandtheassociatedfishcommunityweresampledintheunchannelizedMissouriRiverdownstreamofFortRandallDam,SD,totheheadwatersofLewisandClarkLake,NE-SD,[i.e.,Segments5and6;formerlyRecoveryPriorityManagementArea3(RPMA3)]during2017usingstandardizedPallidSturgeonPopulationAssessmentProgram(PSPAP)protocols.
PropagationandstockingeffortsaremaintainingthepallidsturgeonpopulationinSegments5and6.Allpallidsturgeoncaught(n=42)during2017wereofhatcheryorigin.Todate,noconfirmedwildpallidsturgeon,excludingtranslocatedindividuals,havebeencaughtinSegments5and6duringPSPAPsampling.Pallidsturgeonfrom15ofthe18yearclassesstockedinSegments5and6werecaughtduring2017.Relativeabundanceestimatesofpallidsturgeonin2017weregenerallylowerthanpreviousyearsforgillnets,trammelnetandottertrawl,butwereintermediatefortrotline.Meanconditionofstock-,quality-,andpreferred–lengthclasses(0.89-0.91)wassimilar(Δ≤±0.05)to2016,butconditionofmemorable-lengthfishin2017(0.85)waslowerthanin2016(0.94).Multipleyearclasses(e.g.,2001-2009)haveshownlittlegrowthinmeanlengthinrecentyearsastheyapproach700mmFL.
ShovelnosesturgeonS.platorynchus,bluesuckerCycleptuselongatus,andsaugerSandercanadensepopulationsappeartobedeclininginSegments5and6duetolowrecruitment.Fewshovelnosesturgeon<550mmoccurredinoursampling,suggestingalackofnaturalreproductionorrecruitment.Similarly,wetypicallyonlycatchafew,ifany,adultbluesuckerannually.Finally,fewsmallsauger(i.e.,<100mm)havebeencapturedsince2013,suggestingnaturalrecruitmentmaybeanissueforthispopulation.
53
SturgeonchubMacrhybopsisgelida,shoalchubM.aestivalis,andsicklefinchubM.meekioccuratlowrelativeabundancesorareabsentfromSegments5and6.Onlytwosturgeonchub(collectedin2012)havebeencaughtduring15yearsofmonitoring.SicklefinchubandshoalchubhavenotbeencaughtduringPSPAPsamplinginSegments5and6.
BrassyminnowHybognathushankinsoni,plainsminnowH.placitus,andWesternsilveryminnowH.argyritisaretypicallyrareinSegments5and6.In2017,relativeabundanceofbrassyminnowsreturnedtothelowlevelsobservedinmostpreviousyearsfollowingexceptionallyhighrelativeabundancein2016.
ThesandshinerNotropisstramineuspopulationappearsstableinSegments5and6,butrelativeabundanceofsandshinerdecreasedfrom2016to2017.SandshinersareprimarilycapturedinSegment6(i.e.,downstreamfromtheNiobraraRiverconfluence).
Atotalof4,159fishcomprisedof41speciesandonehybridwerecaughtin2017.Wecaughtatleast50individualsof11non-targetspecies:spotfinshinerCyprinellaspiloptera(n=2,299),bluegillLepomismacrochirus(n=392),bluntnoseminnowPimephalesnotatus(n=184),emeraldshinerNotropisatherinoides(n=140),channelcatfishIctaluruspunctatus(n=139),gizzardshadDorosomacepedianum(n=122)rivercarpsuckerCarpiodescarpio(n=101),greensunfishL.cyanellus(n=56),smallmouthbassMicropterusdolomieu(n=66),shortheadredhorseMoxostomamacrolepidotum(n=70),andshortnosegarLepisosteusplatostomus(n=74).Finally,wecaught24falsemapturtlesGraptemyspseudogeographica.
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Migrations,Aggregations,andSpawningofPallidSturgeonintheYellowstoneRiverduring2017
PatrickJBraaten,U.S.GeologicalSurvey,ColumbiaEnvironmentalResearchCenter,FortPeckProjectOffice,FortPeck,Montana59223;email:[email protected]
Background
TheupperMissouriRiverbasinisinhabitedbyanextantstockof100–125(Jageretal.2008)reproductivelyactivewildpallidsturgeonScaphirhynchusalbus.Thestockisinastateofcompleterecruitmentfailureorsevererecruitmentlimitationasevidencedbythelackofsmallandyoungfishthroughthepastseveraldecades(USFWS2007;Braatenandothers,2015a).Owingtothelackofrecruitment,thewildstockhasbeensupplementedalmostannuallysincethelate1990swithplantsofhatchery–originpallidsturgeon(HOPS)producedfromlocalwildbroodstock.WithintheupperMissouriRiverbasin,pallidsturgeonmigrationandspawningoccursinriversofvaryinganthropogenicalterations.TheYellowstoneRivermaintainsmostlynaturalhydrologicandthermalregimes,butisfragmentedbyirrigationdiversiondams.TheMissouriRiverbetweenFortPeckDamandtheYellowstoneRiverconfluenceishydrologicallyandthermallyaltered.Althoughgenerallyviewedasalarge–riverinhabitant(BaileyandCross,1954),pallidsturgeonalsohaveaccesstomultipletributarieswithintheupperbasinhydrosystem.
Lackingdetailedinformationonpallidsturgeonreproductionwhenthespecieswaslistedasendangeredin1990(USFWS,1993)andextendingintotheearly2000s(USFWS2000;2003),substantialknowledgehasaccruedregardingfundamental–yetcritical–attributesofpallidsturgeonreproductiveecology.Inrecentyears,muchfocusonpallidsturgeonreproductionhasoccurredinthevariedhabitattemplateoftheupperMissouriRiverbasin.Withinthemostlynatural–stateYellowstoneRiver,reproductivebehaviorandecologyhavebeendiscernedwithregardstospatialextentandtemporalaspectsofpre–spawnmigrations,pre–spawnbehaviorwherepersistenceofmaleaggregationsatoneormorelocationsdefinespawningpatches,spawningverification,andquantifyinghydraulicelements(forexample,depth,velocity,substrate)atspawningpatches(Fullerandothers,2008;Braatenandothers,2015b;DeLonayandothers2014,2016a,2016b,2016c;DeLonayandothers,inrevision).BeyondverifyingthatspawningoccursannuallyundermostlynaturalenvironmentalconditionscharacteristicoftheYellowstoneRiver,researchtodatehasalsoidentifiedthatspawningpatchesandassociatedhydraulicelementsareatleastpartiallyfunctionaltofacilitatesuccessfulincubationandhatchofembryosbasedoncollectionsofdispersingpallidsturgeonfreeembryos.
AnnualtrendsinpallidsturgeonreproductiveactivitycentermostheavilyinthelowerYellowstoneRiver;however,departuresfromtrendshavebeenobservedintheupstreamreachesoftheYellowstoneRiver,andalthoughlimitedinoccurrencetodate,thesedepartureslikelyinvolveacombinationofelementsincludingIntakeDam,dischargeinthemainstemandtributaries,andmigrationalmotivationinpallidsturgeon.Forexample,themajorityofwildadultpallidsturgeontypicallyexhibitshort–distancepre–spawnmigrationsandremainlocalizedinthelowerYellowstoneRiver.Inmostyears,about12–16percentofthetelemeteredwildadultsmigratetotheupperreaches
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wheremigrationterminatesatIntakeDam(RM72.8;DeLonayandothers2014,2016a,2016b,2016c).UnderelevateddischargeintheYellowstoneRiver(forexample,39,000ft3/sandhigher),anaturalhigh–flowsidechannel(hereafterHFSC)aroundIntakeDamflowssufficientlytoprovideconditionsenablingpallidsturgeonpassageandaccesstoreachesupstreamfromIntakeDam(DeLonayandothers2016c).IfindividualsfindtheentrancetotheHFSCandaremotivatedtomoveupstream,migrationsmaypersisttotheupperreachesoftheYellowstoneRiver.MigrationspersistingintothePowderRiver(confluencelocatedatYellowstoneRiverRM150)duringelevateddischargeinthissystemweredocumentedforonegravidfemaleandtwomalesin2014,andspawningmostlikelyoccurredinthePowderRiver(DeLonayandothers2016c).Thus,whereasreproductiveactivitiesforthemajorityofwildpallidsturgeonarecenteredinmainstemofthelowerYellowstoneRiver,thePowderRivermayalsofunctionasasuitablespawninglocationconditionaluponpassagethroughthereachimpactedbyIntakeDam,persistentupstreammigration,andsuitabledischargeconditionsinthePowderRiver.
Contrastingwiththenatural–stateYellowstoneRiver,pallidsturgeonmigrationsandreproductiveactivityintheflow–andthermally–alteredMissouriRiverdownstreamfromFortPeckDamarehighlyvariableamongyears.Pre–spawnmigrationsanduseoftheMissouriRiverbywildadultsmaybelowinsomeyears(forexample,in2012,2014,2015);whereas,inotheryears(forexample,2011,2013,2016),30percentormoreoftelemeteredwildpallidsturgeonwithintheMissouri–YellowstonehydrosystemmaymigrateintotheMissouriRiverduringtheMaythroughJunepre–spawntimeframe(DeLonayandothers2014,2016a,2016b,2016c;DeLonayandothers,inrevision).Withinthisalteredenvironment,itishypothesizedthatelevateddischargefromtheMilkRiver,thedam,orincombinationmaypromoteincreasedutilizationoftheMissouriRiverdownstreamfromFortPeck.Aggregationsofmalepallidsturgeonhavebeendetectedperiodically,butifpresent,tendtoincludefewermalesthanobservedforaggregationsintheYellowstoneRiver.SpawningbypallidsturgeonintheMissouriRiverhasbeenverifiedonasingleoccasion,asevidencedduringtheexceptionallyelevatedflowconditionsin2011whenafreeembryowascaptured(DeLonayandothers2014).Asatributarycontributingwarm,turbidwatertodam–releaseflows,theMilkRivermayperiodicallybeusedbymalesandreproductivefemalepallidsturgeon(forexamplein2013;DeLonayandothers2016b);however,spawninginthistributaryhasnotbeendetected.
Researchin2017expandedonearlierinvestigationsofpallidsturgeonreproductiveecologyintheUpperMissouriRiverbasin.ProgresssummarizedinthisreportfocusesonpallidsturgeonintheYellowstoneRiverasprogressontheMissouriRiverissummarizedunderaseparatereportbyMontanaFish,WildlifeandParks(MTFWP).Theobjectivesincluded:1)assessspatiotemporalattributesofpallidsturgeonpre–spawnmigrations,2)identifythelocation(s)andtimingofspawningevents,and3)verifyfunctionalityofspawninghabitatsbasedoncapturesofpallidsturgeonfreeembryosandlarvae.Inpreviousyears,theUSGSandMTFWPwereprimarycollaboratorstoaccomplishprojectobjectives.In2017,theBureauofReclamation(BOR)initiatedaprojectatIntakeDamthatinvolvedthesamepopulationoftelemeteredwildpallidsturgeonandHOPSasexaminedinthepresentstudy.Inthisproject,theBORimplementedatranslocationstudy,wherebytelemeteredwildadultsandHOPSmigratingtoIntakeDamwerecaptured,andtranslocatedupstreamfromthedamtoensurepassageandfacilitatepotentialmigrationstoupstreamareasoftheYellowstoneRiver.Thus,collaborationsin
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2017alsoincludedtheBORastheirtelemetryandrelocationdataexpandeddatasetsforanimprovedspatialunderstandingpallidsturgeonintheYellowstoneRiversystem.
Methods
Theresearchpopulationoftelemeteredpallidsturgeonassessedin2017included57wildadultsandgreaterthan130HOPSofknown,suspected,andunknownsexorreproductivestatus.Additionalwildpallidsturgeonwerepresentinthesystem,butsomewerecapturedandtakentothehatcheryforpropagationin2017andotherswereinfrequentlydetectedduringtelemetrywork.AdditionalHOPSweretransmitteredthroughsummerandfall2017,andcollectively,nearly180HOPScarriedtransmittersbylatefall.Fourwildfemalepallidsturgeoncomprisedthecandidatelistofpotentialspawnersbasedonpre–spawnreproductiveassessmentsofbloodhormones(testosterone,T;estradiol,E2;eggpolarityindex,PI)andweight.Thespawn–candidatefemalesincludedcode43(captureandimplantedon5/3/17,weight=27.5kg,T=84.54ng/ml,E2=4.73ng/ml,PI=0.096),code127(captureandimplantedon5/2/17,weight=25.0kg,T=69.17ng/ml,E2=5.73ng/ml,PI=0.083),andcode87(capture5/11/17,weight=22.5kg,T=46.18ng/ml,E2=3.31ng/ml).Thefourthcandidatefemale(code41)wasnotassessedpre-spawnashertransmitterwasdifficulttodetectandshecouldnotbecaptured(seeProgresssectionbelow),butbasedonherpast2-yearspawnperiodicity(2013,2015),itwasanticipatedthatcode41wouldbeaspawn-candidatein2017.
RadiotelemetryincludingmanualtrackingbyboatanddeploymentofautomatedtelemetrygroundstationswasinitiatedinApril.Pallidsturgeonrelocationpointsandenvironmentalattributesobtainedduringmanualtrackingwererecordedonahighlycustomizedmobilemappingandelectronicdatacollectionapplication.AutomatedtelemetrygroundstationsweredeployedatmultiplelocationsintheYellowstoneRiverincludingneartheconfluence(RM0.75),atRM7.0,RM39.0,RM61.5,IntakeDam(RM72.8),RM99.0,RM115.0,andatthePowderRiverconfluence(RM147.0).TelemetrygroundstationswerealsodeployedwithintheHFSCadjacenttoIntakeDamnearthedownstream(RM71.0)andupstream(RM75.0)connectionstothemainstemriver.Inaddition,telemetrygroundstationsweredeployedintheMissouriRiverandMilkRiverasdescribedintheMTFWPreport.Groundstationdetectionscomplementedwithmanualtrackingrelocationsprovidedacontinuousassessmentofmigrationsandmovementswithinandamongrivers.
SamplingforpallidsturgeonearlylifestageswasconductedinthelowerYellowstoneRiverandPowderRivertoverifyhatchanddrift–entryoffreeembryosandpotentiallyextendeddispersaloflarvae.SamplingintheYellowstoneRiveroccurredJune7–27primarilybetweenRM3.2–5.6,andinthePowderRiver,samplingwasconductedduringJune12–19.Samplingforpallidsturgeonfreeembryosandlarvaewasconductedusing3.0-mlongtaperedrectangularnets(1.0mmmesh)affixedtorectangularframes(0.75-mwidth,0.5-mheight;seeBraatenandothers,2010).Pairednetsweresimultaneouslydeployedfromtheportandstarboardsidesoftheboatbow,andfishedinthelower0.5–mofthewatercolumnadjacenttotheriverbed.Asoundingweightorpaireddownriggerweightswereattachedtothenetframetomaintainnetcontactwiththeriverbed.Samplecontentswereflushedfromthenetandterminalcollectingcup,transferredtoblackpans,andAcipenseriformes(shovelnosesturgeon,pallidsturgeon,paddlefish)freeembryosandlarvaewerelive–extractedfrom
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thedetritus.Specimenswereimmediatelypreservedinvialscontaining95percentnon–denaturedethanol.Inthelaboratory,preservedspecimensweretentativelyidentifiedasScaphirhynchussp.,paddlefish,orunknown(thatis,damagedbeyonddefinitiverecognitionbecauseofsmashedbodiesormissingbodyparts)basedonmorphometricandmeristiccharacters,measured,andphotographed.PreservedAcipenseriformesweresenttoDr.EdHeist(SouthernIllinoisUniversity)forgeneticanalysis(Eichelbergerandothers,2014)todifferentiatespecimensasshovelnosesturgeon,pallidsturgeonorpaddlefish.
Progress
HydrologicandThermalRegime
FlowconditionsintheYellowstoneRiverandtributariestendedhigherin2017thanlong–termaverages.AveragedischargeintheYellowstoneRiverrecordedatSidney,Montana(USGSgagenumber06329500)duringApril(19,157ft3/s),May(34,039ft3/s),andJune(44,357ft3/s)was180,186,and115percent,respectively,oflong-termconditions(1911–2016)forthesemonths.DischargeatSidneyinitiallypeakedonMay17(45,800ft3/s),andtheseasonalmaximaoccurredonJune10(57,300ft3/s;Braaten_Figure1).ElevateddischargesinthelowerYellowstoneRiverwerepartiallyattributedtoelevateddamreleasesintheBighornRiversystem(confluenceatRM295;USGSgagenumber06294500)asflowsaveraged11,550ft3/sinApril(311percentofnormal),14,770ft3/sinMay(327percentofnormal),and11,840ft3/sinJune(192percentofnormal).DischargeinthePowderRiver(Braaten_Figure1)wasalsogreaterthanlong-termconditionsasflowsinApril(mean=898ft3/s),May(2,479ft3/s),andJune(mean=1,969ft3/s)were126,205,and121percent,respectively,oflong-termrecords(1939–2017;USGSgagenumber06326500).DischargeinthePowderRiverwasgreatestinmid-May(May16–21,2,930–3,130ft3/s),declinedfromlate-MaythroughearlyJune,thenincreasedonJune16(2,860ft3/s)beforedecliningintolateJune.WatertemperatureintheYellowstoneRiver(Braaten_Figure1)progressivelywarmedfromApril25(9.2oC)toMay14(17.8oC),butwithincreasingdischarge,temperaturedeclinedto14.0oCbyMay21.Watertemperatureincreasedto20.1oCbyJune10,thendeclinedto17.7oConJune18.WatertemperatureremainedrelativelycoolduringJune19–June25(18.3–19.2oC,mean=18.7oC)beforeincreasingtosummermaximainJuly.
PallidSturgeonUseoftheYellowstoneRiver
PallidsturgeoninitiatedmovingintotheYellowstoneRiverbyearlyApril,andbyearlyMay,greaterthan70percentoftelemeteredwildadultswerepresentintheYellowstoneRiver(Braaten_Figure2).PallidsturgeoncontinuedmovingintotheYellowstoneRiverduringMay,andbyJune1,91%ofthetelemeteredresearchpopulationofwildadultsutilizedtheYellowstoneRiversystem.UsediminishedgraduallythroughJune22(greaterthan70%remained).DuringlateJuneandearlyJuly,pallidsturgeoncontinuedemigratingfromtheYellowstoneRiverasdischargedeclined.
MigrationstoandUpstreamofIntakeDam
ManualtelemetrycomplementedwithdetectionsfromloggingstationsidentifiedmigrationsofwildpallidsturgeonandHOPStoIntakeDam,andthroughtheHFSCadjacenttothedam.Fivewildmale
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pallidsturgeon(8.8%ofthetelemeteredwildpopulation;codes11,49,57,61,83)weredetecteddownstreamfromIntakeDam;theearliestarrivaloccurredonMay6-8(mainstemdischarge=22,900–23,700ft3/s;Braaten_Figure3;Braaten_Table1).Atotalof14HOPSwerealsodetectedatIntakeDam(Braaten_Table1).EarliestdetectionsforHOPSatIntakeDamoccurredinearlyApril(code91,April3-9;code72,April7-11;mainstemdischarge16,800–18,200ft3/s).BothoftheseHOPSwerealsodetectedbelowthedaminOctober2016.AlthoughseveralHOPSwereimplantedwithtransmittersincloseproximitytoIntakeDamandeventuallyprogressedashort–distanceupstreamtothedam,someHOPSalsoexhibitedsubstantialmigrationsthatterminatedatIntakeDam.Forexample,HOPSmalecode62(sexdeterminedbyvisualobservationoftestesduringsurgeryandelevatedT=217.6ng/ml)wasimplantedonMay3atRM6.6oftheYellowstoneRiver,andmigratedupstreamtoIntakewhereinitiallydetectedonMay13.AsecondHOPSalsoexhibitedalong-distancemigrationasmalecode98(T=94.63ng/ml)wasimplantedonMay16atRM1,710.5oftheMissouriRiver,andwasinitiallydetectedatIntakeonAugust18.
WhereastheupstreammigrationextentforseveralpallidsturgeonterminatedatIntakeDam,fourpallidsturgeon(wildmalecodes49,61;HOPScodes66,160)swamthroughtheHFSCtocontinueupstreammigrations(Braaten_Table1).TheearliestmigrationthroughtheHFSCoccurredonMay15–16forHOPScode160whenmainstemdischargewas40,000–44,600ft3/s.DuringJune6–13,thethreeotherpallidsturgeonmovedthroughtheHFSCatdischargesrangingfrom52,200–57,300ft3/s.Twootherpallidsturgeon(HOPScodes154,155)weredetectedbytheHFSCdownstreamloggingstationandmanuallyrelocatedwithinthesidechannelonseveraldates,butdidnotswimthroughtheentirelengthoftheHFSC.
ThroughthecombinationoftranslocationofpallidsturgeonimplementedbytheBORandvolitionalswimmingthroughtheHFSC,migrationsforninepallidsturgeonpersistedupstreamfromIntakeDam(Braaten_Table1).Migrationsforsixpallidsturgeon(wildmalescodes49,61;HOPScodes54,66,160,169)extendedtoRM75.0–123.4oftheYellowstoneRiver.UpstreammigrationsforthreeotherpallidsturgeonpersistedthroughtheYellowstoneRiver,andintothePowderRiver(Braaten_Figure3;Braaten_Table1).AftertranslocationonMay8,wildpallidsturgeonmalecode83wasdetectedatYellowstoneRiverRM92.6onMay10andatthePowderRiverconfluenceloggingstationonMay15.Followinganinitiallyincreasing(May16–21;2,930–3,130ft3/s)thendecreasinghydrograph(May22–June1;2,120–2,820ft3/s),code83waslocatedonJune1atPowderRiverRM89.9duringanaerialsurveyconductedbyMTFWP.Code83wassubsequentlydetectedinthePowderRiveratRM80.4onJune9andatthePowderRiverconfluenceloggingstationonJune19,swamdownstreambetweenYellowstoneRiverRM99.0andIntakeDamonJune20,wasdetectedatRM63.4andRM39.0onJune21andJune22,respectively,andrelocatedatRM7.0onJune23.Code91(HOPS)wastranslocatedonMay10,anddetectedatthePowderRiverconfluencegroundstationonMay20.ThisindividualpersistedmovingupthePowderRiver,beingrelocatedatRM11.3onMay23,RM16.4–17.3onMay25,andaeriallydetectedbyMTFWPatPowderRiverRM65.9onJune1andRM97.0onJune9.Upstreamprogressionofcode91inthePowderRiveroccurredduringperiodsofdeclining(May21–June2;2,040–3,130ft3/s)andincreasingflows(June3–June9;2,090–2,450ft3/s).Thefinalrelocationofcode91occurredonJuly29atRM95.5,andthetransmitterandremainsofthefishwere
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found.Wildpallidsturgeonmalecode11wasthethirdknownpallidsturgeontoutilizethePowderRiver.AftertranslocationonMay14,code11movedupstreamandwasdetectedatthePowderRiverconfluenceloggingstationonMay22.UtilizationofthePowderRiverbycode11wasverifiedbasedonrelocationsforMay23(RM9.4),May25(RM26.2),andaerialdetectionsbyMTFWPonJune1(RM88.1)andJune9(RM4.0).DuringtheMay23–June1upstreammigrationforcode11,dischargewasprimarilydeclininginthePowderRiver(2,120–2,700ft3/s).Subsequentrelocationsforcode11includedthePowderRiverloggingstationonJune12,YellowstoneRiverRM107.8onJune13,detectionsatRM99.0,IntakeDamandRM39.0onJune14,andthelowerYellowstoneRiverthroughlateJune.
MaleAggregationsandPallidSturgeonSpawningChronology
TransitoryandpersistentaggregationsofwildmalepallidsturgeonandHOPS(knownmaleandunknownsex)wereobservedinthelowerYellowstoneRiverduring2017(Braaten_Figure4).DuringMayandearlyJune,lowtolargenumbersofpallidsturgeonwerenotedinseverallocationswithlargeearly–seasonaggregationsoccurringonMay10atRM6.5(10fish),May16atRM2.6(12fish),May23atRM2.5(8fish),May31atRM6.3(9fish),May31atRM2.2(10fish),June1atRM6.1(14fish),andJune2atRM6.0(17fish);however,theseaggregationsearlyintheseasonweretransitoryandnotpersistentformultipledays.FromJune8throughJune22,persistentandfrequentlylargeaggregations(greaterthan8fish)werepresentbetweenRM5.4–6.1.AsecondaryaggregationalsooccurredbetweenRM4.7–4.8duringJune15–18,butthisaggregationdisbandedasmalesandHOPSre-aggregatedattheRM5.4–6.1aggregationsite.
Pallidsturgeonfemalecode43wasthelargest(27.5kg)spawn–candidatefemaleintheresearchpopulationfor2017.ThisfemaleremainedmostlylocalizedinthelowerYellowstoneRiver,exhibitinglimitedup-anddownstreampre–spawnmigrationswherethemaximumobservedupstreamlocationoccurredatRM11.2onMay16(Braaten_Figure5).FromJune1–17,minimalmovementswereobservedforcode43asshewasdetectedonlybetweenRM5.6–7.1.OnthemorningofJune18(~10:00AM),code43waslocatedatRM5.9intheareawhereseveralmaleshadbeenaggregatedinpreviousdays;however,onlyoneotherfish(HOPScode157)wasdetectedincloseproximity.Atabout3:00PMonJune18,femalecode43andmales(wildfishcodes73,82,90,193;HOPScode62)wereaggregatedatRM5.8insuspectedspawningactivity.Throughabout5:30PM,code43andthemales(withadditionofwildfishcode77)remainedatRM5.5–6.0.OnthemorningofJune19,relocationsduring9:50AM–11:15AMidentifiedmultiplemales(wildcodes10,11,48,57,59,73,77,82,193;HOPScodes132,157)remainedaggregatedatRM5.7–5.9;however,femalecode43wasabsentfromtheaggregation.Code43waslocateddownstreamatRM4.6(10:40AM)wheresheexhibitedminimalmovement(RM4.5–4.6)throughlateafternoon.Suspectingthatspawningwascompletedbasedonherdeparturefromthemaleaggregation(asisthetypicalbehavior),code43wouldhavebeentargetedforimmediatecapturetoverifyspawning.However,asecondspawningeventinvolvingfemalecode87hadbeeninitiated(seebelow),andcrewsfocusedeffortsoncode87fortheday.Femalecode43wascapturedonJune20atRM4.7;sheweighed4.0kgless(23.5kg)thanpre–spawn(27.5kg),indicativeofa14.5%weightlossduetoeggdeposition.Bloodsamplesobtaineduponcapturebutanalyzedlateralsoindicatedpost–spawnhormonelevels(T=0.83ng/ml,E2=not–detectible).Basedonthese
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results,thespawningchronologyforcode43likelyincludedthefollowingscenario:spawningwasinitiatedonJune18between10:00AM(nomaleaggregation)and3:00PM(withmaleaggregation)aroundRM5.8,persistedatRM5.4–6.0,andconcludedpriorto9:50AMonJune19(code43absent).Environmentalconditionsduringthecode43spawningeventincludedameandischargeof38,600ft3/s(June18)and36,700ft3/s(June19),andmeantemperature17.7oC(June18)and18.3oC(June19).
Femalecode87wasasecondspawn–candidatefor2017.ThisfemaleexhibitedaprogressiveupstreammigrationduringearlyMaythatpersistedtoRM29.4onMay11whenshewascapturedandassessed(weight=22.5kg;Braaten_Figure5).Followingthismaximumupstreampre–spawnmigration,code87movedupstreamanddownstreamthroughthelowerYellowstoneRiverduringmid–Maythroughmid–JunewithanupstreammigrationtoRM13.8onJune8.OnJune16,alargeaggregationofmales(forexample,wildfishcodes32,48,59,75,77,82,193,196;HOPScode128)waspresentatRM4.7–4.8duringthemorningandafternoon;however,femalecode87swamthroughthisaggregationandpersistedmovingupstream.Multiplepallidsturgeon(forexample,wildfishcodes10,11,27,42,73;HOPScodes100,132,157)werealsodetectedatRM5.4–6.1onJune16,butcode87alsomovedupstreampastthesefishasshewasfoundatRM16.6onJune17.OnthemorningofJune18,code43wasdetectedatRM11.0movingdownstream,andbyevening(6:25PM)waslocatedatRM5.8.OnthemorningofJune19,code87wasinitiallylocatedatRM5.3(10:22AM),butbyaboutnoon,shehadmovedupstreamtoRM6.0pastthemaleaggregation(wildcodes10,11,48,57,59,73,77,82,193;HOPScodes132,157)aggregatedatRM5.7–5.9.Fromabout2:40PMthrough8:35PMonJune19,code87andmultiplemales(codes10,11,48,57,59,73,77,82,193,196;HOPScode62)wereengagedinpresumedspawningactivityatRM5.4–6.0ascrewsrecordedmultiplepointsonthefishinthisareaoftheriver.CrewsreturnedonJune20,andalthoughmultiplemaleswerepresentatRM5.3–6.0(codes10,11,48,57,59,73,77,82,196;HOPScode100),femalecode87wasabsentfromtheaggregationsiteandwasrelocatedatRM4.3(11:44AM).Code87wasre–capturedonJune20atRM3.7andweighed19.0kg,3.5kglessthanherpre-spawnweight(15.6%weightlossduetoeggdeposition).Abloodsampleobtainedatthetimeofcaptureandanalyzedlateralsoverifiedspawningthroughchangesinreproductivehormones(T=4.31ng/ml,E2=not–detectible).Thespawningchronologyforfemalecode87likelyincludedthefollowingscenario:initiationofspawningatRM5.5onJune19betweenaboutnoonand2:40PM(whenshewasfirstdetectedwithmalegroup),persistentspawningactivityatRM5.4–6.0throughabout8:35PM(basedonnumerousmale–femalerelocations),andspawncompletionby11:44AMonJune20.AveragedischargeduringJune19andJune20was36,700ft3/sand40,200ft3/s,respectively,andwatertemperatureaveraged18.3oCand18.8oCfortherespectivedates.
Femalecode41wasasuspectedspawn–candidatepallidsturgeonfor2017.However,thisfemalewasnotcapturedforpre–spawnassessmentsasthetransmittersignalwasdifficulttodetectandpinpointintheriverchannelforcapture.Whendetectedpre–spawn,nettingeffortswereunsuccessful.Uponcapturelaterintheseason(seebelow),itwasobservedthatthetransmitterantennaewasbrokenofflikelycontributingtolowdetectabilityforthisfish.Basedonthe2–yearspawningcycleevidentfromearlierstudies(forexample,spawnerin2013,2015),code41remainedatargetfemaleforthe2017spawningwork,andcrewstriedtomaintaincontactwithandrelocatethis
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femaleduringtrackingruns.Relocationsforcode41indicatedthisfishremainedlocalizedinthelowerYellowstoneRiverwherethegreatestupstreamdetection(RM7.6)occurredonMay16(Braaten_Figure5).FromJune7–14,code41exhibitedlittlemovementandwascontactedinthelowerYellowstoneRiverbetweenRM0.1–0.3.RelativelyconsistentcontactwasobtainedduringJune19–June23ascode41movedintodetectiblelocations.OnJune19,code41wasrelocatedmultipletimesatRM3.1–3.2,butonlyoneotherfish(HOPScode25)wasnearby.Code41wasrelocatedslightlyupstreamonJune20(RM3.9),butnomalepallidsturgeonwereincloseproximity.OnJune21,crewsrelocatedandmaintainedsurveillanceoncode41atRM4.1–4.2asthefemalehadmovedslightlyupstream.Twopallidsturgeon(wildmalecode75;HOPScode127)werelocatednearbycode41.At11:00AMonthemorningofJune22,code41wasinitiallylocatedatRM3.9inasmallaggregationincludingwildmales(codes59,75,77)andHOPScode25.Crewsmaintainedsurveillanceoncode41duringtheday,andidentifiedthatwildmalecode196andHOPScodes62and127werealsointhearea.Byabout4:30PMonJune22,code41hadmoveddownstreamtoRM3.4andtwowildmales(codes59,196)werecloselyassociatedwithher.Suspectingthatspawningwascompletedornearlycompletedbasedonherdownstreammovement,code41wastargetedforcapture.Nettingattemptswereunsuccessfulforcode41asthefemalecontinuedtomovedownstream,andultimatelysettledinanoutsidebendlocationcontainingemergentandsubmergedtrees;however,wildmalecode196whowascloselyassociatedwithherwascapturedduringnettingandobservedtobereleasingmilt.Code41wascapturedonJune23,weighed25.0kg,andbasedonthelackofeggsinthebodycavity,wasdeterminedaspost–spawn.Abloodsampleobtainedatcaptureandanalyzedlaterindicatednon-detectiblelevelsofTandE2.Additionally,asampleofovariantissuewasobtainedforanalysis.Histologicalanalysisoftheovariantissueindicatedpost–ovulatoryfollicles,indicativeofrecentspawning(Dr.MollyWebb,USFWS,pers.comm.).EnvironmentalconditionsduringtheJune21–22suspectedspawningeventforcode41includedameandischargeof40,350ft3/sandmeanwatertemperatureof19.2oC.
Femalecode127wasthefourthspawn–candidatepallidsturgeonfor2017.AfterinitialcaptureandtransmitterimplantationonMay2,thisfemaleremainedrelativelylocalizedinthelowerYellowstoneRiverduringMay(Braaten_Figure5)withhermostupstreamrelocationpointoccurringatRM11.1onMay12.OnMay31at7:11PM,code127andseveralwildmalepallidsturgeon(codes8,17,23,27,77,81,82,89,91,93)wereaggregatedatRM2.2.Spawningwasnotsuspectedonthisearlydateaswatertemperaturewascool(17.3oCat7:11PM)andhadbeencoolinprecedingdays(May29mean=15.4oC,May30mean=15.7oC).Furthermore,basedonearlieryearsofstudy,itisnotuncommonforafemaletotemporarilyaggregatewithmalesearlyintheseasonpriortocontinuingmigratorybehavior.Code127wasrelocatedatRM2.4onJune1,butonlytwowildmales(codes17,91)wereintheneararea.OnJune2,code127wasinthesamegeneralarea(RM2.3at11:50AM)withfemalecode87andwildmalecode17inthearea.Code127wasrelocatedinasimilarlocationonJune6(RM2.4),butotherpallidsturgeonwerelackingfromthearea.DespitetrackinginthelowerYellowstoneRiveronJune7–8,code127wasnotrelocated.TrackinginsubsequentdayswasexpandedtotheMissouriRiverdownstreamfromtheYellowstoneRiverconfluenceinsearchofcode127,andthefemalewasrelocatedatRM1,580.0–1,580.6fromJune9–11.Itwasanticipatedthatcode127wouldmovebackintotheYellowstoneRiveraspartofherpre–spawnmigration;however,
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thefemalewasnotfoundagainuntilJuly19whenrelocatedintheMissouriRiveratRM1,567.4(depth=7.6meters,23.8oC).Code127wasnotrecapturedtoverifyifspawninghad/hadnotoccurred.
VerificationofHatchandDispersalofPallidSturgeonFreeEmbryosandLarvae
Samplingforpallidsturgeoneggs,developingembryos,anddispersingfreeembryosandlarvaewasinitiatedonJune7priortoknownspawningevents,andcontinuedthroughJune27tocoincidewithexpectedincubationandhatchtimelinesfromthefinalspawningeventinvolvingfemalecode41.CollectiveeffortsbetweenUSGSandMTFWPforthelowerYellowstoneRiverincluded477samplesacrossdatesthatresultedin794Acipenseriformeseggsanddevelopingembryos,and1,685Acipenseriformesfreeembryosandlarvae(Braaten_Table2).Nearly48percentoftheeggsanddevelopingembryos,and79percentofthefreeembryosandlarvaewerecollectedfromJune19–27followingtheinitiationofknownspawningeventsintheYellowstoneRiver.SamplingforpotentialpallidsturgeonearlylifestagesinthePowderRiverwasconductedbyMTFWPpersonnelduringJune12–19.Throughthissampling,fiveeggsanddevelopingembryoswerecollectedalongwith35dispersingAcipenseriformesfreeembryosandlarvae.Specimensfrombothriversystemsweremeasuredandtentativelyidentifiedinthelaboratoryaspaddlefish,Scaphirhynchussp.,orunknown(duetomashedbodies,broken,tornormissingportionsofbodies,etc.).Specimensareintheprocessofgenetictestingtodifferentiateindividualsaspaddlefish,shovelnosesturgeonorpallidsturgeonfollowingmethodsofEichelbergerandothers(2014).
Discussion
PallidsturgeonintheupperMissouriRiverbasinhavetheabilitytousethenatural–stateYellowstoneRiverandflow–andtemperature–alteredMissouriRiverforpre–spawnmigrations.In2017,telemeteredwildadultsprimarilyusedtheYellowstoneRiveraspre–spawnmigrationsintotheriverwereinitiatedinApril,andmaximumuse(91percent)wasattainedbyearlyJune.Workduring2012–2016alsodocumentedprimaryuseoftheYellowstoneRiverwhere83–93percentofthetelemeteredwildpallidsturgeonmovedintotheriverbylateMayandearlyJune(DeLonayandothers,2016a,2016b,2016c;DeLonayandothers,inrevision).Adivergencefromthisgeneraltrendwasobservedduringextremelyelevatedflowconditionsin2011whenabout60percentofthewildadultsusedtheYellowstoneRiver,and35–40percentusedtheMissouriRiverdownstreamfromFortPeckDam(DeLonayandothers2014).
AfterenteringandmaintainingresidencyintheYellowstoneRiver,mostwildadultsremainedinthelowerportionsoftheriver;however,pre–spawnmigrationsforfivewildadultpallidsturgeon(about9percentofthetelemeteredresearchpopulation)in2017persistedtoIntakeDamwithinitialarrivaltothedam(malecode83)occurringonMay6–8.Datafrom2012–2016identifiedthatabout12–16percentoftelemeteredadultsweredetectedatIntakeDam,withthegreatestproportion(26percent)detectedatIntakeDamduring2011(DeLonayandothers,2016a,2016b,2016c;DeLonayandothers,inrevision);datesforinitialarrivalofwildpallidsturgeontoIntakeDamduring2011–2016spannedfromearlyApriltomid–May.Althoughseveralyearsofdatacenteredonwildadultshave
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providedinferencesonpre–spawnmigrationsextendingtoIntakeDam,informationonmovementsbyanduseoftheYellowstoneRivernearIntakeDamforHOPSisexpandingasthenumberoftelemeteredHOPScontinuestoincrease.Atotalof14HOPSwasdetectedatIntakeDamduringthe2017fieldseason.DetectionsforHOPSspannedfromearlyAprilthroughOctoberlikelyrepresentingacombinationofbehaviorsincludingshort–andlong–distancemigrationsterminatingatthedamandresidencydownstreamfromthedam.Forexample,twoHOPS(codes72,91)hadearlyAprildetectionsatIntakeDamandlikelyrepresentedpallidsturgeonthatover–winteredincloseproximitytothedam.Comparatively,reproductiveHOPSmalecode62wastransmitteredonMay3atRM6.6oftheYellowstoneRiver,migratedupstream,andarrivedatIntakeDamonMay13whereitremainedforafewdays.Asecondreproductivemale(HOPScode98)wastelemeteredonMay16intheMissouriRiverabout130milesupstreamfromtheYellowstoneRiverconfluence.ThisHOPSmoveddownstreamintheMissouriRiver,movedupstreamintheYellowstoneRiver,thenarrivedatIntakeDamonAugust18(nominalmigrationdistance~200miles).Collectively,HOPS(reproductiveandnon–reproductive)areexpressingpotentiallybroad–scalemovementswithinandbetweentheMissouriandYellowstoneRivers,andasevidencedfrom2017,anincreasingnumberofHOPSarebeingdetectedatIntakeDam.
AlthoughIntakeDammayimpedeorcompletelyblockpallidsturgeonmigrationswithinthemainchanneloftheYellowstoneRiver,thenaturalHFSCcircumventingtheIntakereachcanfunctiontoprovidepartiallongitudinalconnectivityduringsometimeperiodsandfacilitatemigrationaccesstoareasupstreamfromIntakeDam.In2017,two(codes49,61)offivewildpallidsturgeonandtwo(codes66,160)of14HOPSdetectednearIntakeDamusedandfullynegotiatedtheHFSCtocontinuemovingupstream.DischargewithintheHFSCwasnotmeasuredondateswhenpassageoccurred,butdischargeinthemainstemriverwas40,000–44,600ft3/sduringtheearliestpassageevent(May15,16)and52,200–57,300ft3/s(forsubsequentpassageevents(June6–13).UseandcompletenegotiationoftheHFSCbypallidsturgeonin2017occurredwithinflowrangesreportedinearlieryears.Forexample,fivewildadultpallidsturgeon(1female,4males)swamthroughtheHFSCin2014whenmainstemdischargewas47,300–68,100ft3/s(DeLonayandothers,2016c),andin2015,passagethroughtheHFSCoccurredforawildadultmalepallidsturgeonatdischargesof39,500–42,300ft3/s(DeLonayandothers,inrevision).Basedonfindingsfromthesepassageevents,hydraulicconditionsinthenaturalHFSCshouldbesuitableforpallidsturgeonpassagewhendischargeinthemainstemriverisabout39,500–68,100ft3/s.However,suitabledischargeandthepresenceofpallidsturgeonintheHFSCcannotensurethatpassagewilloccurasevidencedfortwoHOPS(codes154,155)thatweredetectedinthelowerportion,butneverfullyascendedtheHFSC.Forexample,HOPScode154wasinitiallydetectedintheHFSConMay18–20whendischargewasmoderatelylow(USGSgageatGlendive06327500,37,700–39,500;USGSgageatSidney06329500,38,700–41,600).DespiteexperiencingelevateddischargeslaterwhileintheHFSC,HOPScode154didnotpersistinmigratingupstream.TheHOPScode155alsoexperiencedelevateddischargewhileintheHFSC,butpassagedidnotoccur.
PallidsturgeonthatswamthroughthesidechannelorweretranslocatedaroundIntakeDambyBORpersonnelhadpotentialtocontinuemovingupstream.Resultsfrom2017forbothgroupsofpallidsturgeonarehighlyrelevanttoproposedworkinfutureyears,andaddtoinferencesonmainstemandtributaryusegainedfromearlierstudyyears.First,althoughtranslocationofpallidsturgeonaround
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IntakeDamwasmandatedunderReasonableandPrudentMeasure2inthe2016IntakeBiologicalOpinion,therewasmuchuncertaintywiththetechniqueastranslocationhadnotbeenconductedwithpallidsturgeonfromwhichresponsesfollowinghuman–handlingcouldbepredicted.Translocation(alsocommonlyreferredtoascatchandhaul)hadbeenimplementedinlakesturgeonAcipenserfulvescens(McDougalletal.2013)andwhitesturgeonA.transmontanus(Rust2011).Implementedasapilotprojectin2017,translocationwassuccessfulforthetwowildandthreeHOPSascontinuedupstreammigrationoratleastlocalizedresidencynearthetranslocationreleasesitewasobservedforallindividuals;fall–back(immediate,rapiddownstreammovementfollowingtranslocation)didnotoccur.Thus,althoughthe2017samplesizewassmall,resultssuggestthatpallidsturgeontranslocationinfutureyearscanfacilitatecontinuedupstreammigrationsofpallidsturgeonbeyondIntakeDam;however,post–translocationbehavioraldeviationsmayoccurdependingonfishreproductivestate,motivation,andhandlingpractices.Translocationisplannedforcontinuedimplementationin2018.
Second,whereassixpallidsturgeon(2translocated,4free–swimmingmigrantsthroughHFSC)exhibitedmovementsuptoaboutYellowstoneRiverRM123.0,threetranslocatedmalepallidsturgeon(2wild,1HOPS)migratedtoRM149.0(PowderRiverconfluence),andthencontinuedupstreaminthePowderRiverwhereterminalrelocationsoccurredbetweenRM88.1–97.0.UseofthePowderRiverin2017complementsobservationsfrom2014whenareproductivewildfemale(code36)andtwowildmales(codes61,68)usedthePowderRiver(DeLonayandothers,2016c),andspawningoccurredwithinthelower20milesmostlikelyduringJune10–17timeframe.LackingaknownreproductivetelemeteredfemaleinthePowderRiverfromwhichchangesinreproductivestatuscouldbeusedtoverifyspawning,definitivespawninginthePowderRiverduring2017wasnotascertained.Itispossiblethataspawneventinvolvingoneormorenon–transmitteredfemalesandpotentiallyothernon–transmitteredmalescouldhaveoccurredonoraboutJune1whenthetwowildmales(codes11,83)wereaeriallylocatedbyMTFWPneartheirmigrationapex(RM88.1–89.9).However,aJune1spawningdatewouldhavebeenearlybasedonthetimingoftypicalknownspawningevents(forexample,mid–tolate–June).Thevariedmovementbehaviorsforthemalesalsomakesitdifficulttodiscernif,where,andwhenspawningoccurred.Forexample,followingtheJune1apexlocationforcodes11and83,detectionsinthePowderRiveronJune9indicatedthatcode11wasnearRM4.0andcode11wasnearRM80.0,whileHOPScode91maintainedanupstreamtrajectorybeingfoundnearRM97.0.Thevariedmalemovementscouldrepresentdifferentreproductivestates,includingcompletionofspawnandriverexit(forexample,code11)orcontinuedreproductivereadiness(codes83,91).
Resultsfrom2014and2017provideinferencestosuggestthatthePowderRivercanbeamigrationdestinationforpallidsturgeon,conditionalonpassagearoundIntakeDamandpersistentelevatedflowconditionsinthePowderRiver.Resultsalsosuggest,however,thatonlyaportionofthepallidsturgeonupstreamfromIntakeDammayusethePowderRiverinanygivenyear.Forexample,one–thirdofthe9telemeteredpallidsturgeonupstreamfromIntakeDamin2017persistedmigratingintothePowderRiver;percentagesmaychangefromyeartoyeardependingonorigin(forexample,wildversushatchery),reproductivestatus,andmigratorymotivation.Collectively,useofthePowderRiverontheYellowstoneRiverorothertributariessuchastheMilkRiverontheMissouriRiverneedscontinuedevaluationtodeterminetheecologicalvalueofthesesystemstopallidsturgeon;the
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progressivelyincreasingnumbersofwildadultsandmaturingHOPSimplantedwithtransmittersprovidetheopportunityfortheseevaluations.
ThetemporaloccurrenceandspatialextentofpallidsturgeonaggregationsinthelowerYellowstoneRiverobservedin2017weremostlyconsistentwithearlierinvestigativeyears.Smallandlargeaggregationscomprisedofwildmales,knownHOPSmales,andunknownsexHOPSwerefoundinthelowerninemilesoftheYellowstoneRiverduringMaythroughearlyJune,butmostearlyseasonaggregationspersistedforonlyafewdays.AfterearlyJune,theprimaryaggregationoccurredatRM5.4–6.1andthisareawaslateridentifiedastheknownprimaryspawninglocationinvolvingreproductivefemalescodes43and87.AsecondaryaggregationofwildmalesandHOPSwasobservedforafewdaysinmid–JuneatRM4.7–4.8,butitisunknownifspawningoccurredwithinthisaggregationasthespawningeventwouldhaveincludednon–telemeteredfemales.Whereasearlierdescriptionsandquantificationsofpallidsturgeonaggregationshavecenteredonwildmales,itisbecomingincreasingevidentthatmultipleHOPSarepresentwithintheaggregationsorarelocatedinnear–proximitytothewildmales.TheincreasedpresenceofHOPSwithintheaggregationsislikelyattributabletotwofactors.First,thenumberoftelemeteredHOPShasincreasedoverthelastfewyears,andsecond,anincreasingnumberofHOPSareachievingsexuallymaturitytostimulateparticipationinreproductiveeventssimilartothewildmales.Forexample,a2006yearclassHOPSwascapturedonMay23,andimplantedwithcode100.Largetesteswereobservedduringsurgicalprocedures,andhormoneanalysisclearlyindicatedreproductivestatus(T=141.51ng/ml).ThisHOPSmaleandseveralotherswerepresentwithinorontheperipheryofwildmaleaggregationsonseveraloccasions.TheextenttowhichthecontinuallyincreasingnumberofreproductivemaleHOPSwillinfluencereproductiveprocessesisuncertain.Forexample,asnumbersofsexuallymatureHOPSmalesincrease,willthenumberofmaleswithintheprimaryaggregation/spawningpatchdoubleortripleinfutureyearsorwillanincreasednumberofaggregationsformoveralargerspatialextentwhereeachaggregationincludesfewermales?
Spawningeventsinvolvingthreetelemeteredfemalepallidsturgeonwereverifiedin2017.Spawningfortwofemales(codes43,87)occurredwithinRM5.4–6.1ofthelowerYellowstoneRiverwheretheprimaryaggregationofmalesalsooccurred.Thisaggregationandspawningareaoverlappedwithverifiedspawningpatchesduringearlieryearsasidentifiedin2013(RM5.7–5.9),2014(RM5.3–5.8),and2015(RM5.8–5.9;DeLonayandothers,2016b,2016c;DeLonayandothers,inrevision).Differentfromfemalecodes43and87,spawningforcode41occurredatadownstreamlocation(RM3.7–4.1)andinvolvedareducednumberofmalesincomparisontothelargeraggregationupstream.Theresults,combinedwithpreviousstudies,expandinferencesidentifyingthelowerYellowstoneRiverasaconsistentspawningareaforpallidsturgeonandthatspawningmayoccuratoneormorepatches.AlthoughspawningmayoccurannuallyinthelowerYellowstoneRiver,isolatedaccountsofspawninghavealsobeenverifiedinotherareasincludingthePowderRiverduring2014andtheMissouriRiverdownstreamfromFortPeckDamin2011.WhereasmostspatialandtemporalattributesofspawninginthelowerYellowstoneRiverduring2017weresimilartopreviousyears,spawningoccurredatslightlycoolertemperaturesthanobservedinpastyears.Forexample,dailytemperaturesduringspawningeventsaveraged17.7–18.3oC(code43),18.3–18.8oC(code87),and19.2–19.3oC(code41).
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PreviousverifiedspawningeventsinthelowerYellowstoneRiveroccurredatdailyaveragesof20.3–22.1oC.
SpawningpatchesusedbypallidsturgeoninthelowerYellowstoneRivercanbefunctionaltosupportfertilization,incubation,andhatchofembryosasevidencedfromcapturesofgeneticallyconfirmedpallidsturgeoninpastyears.Samplingin2017yieldedthegreatestnumberofAcipenseriformesfreeembryosandlarvaecollected(about1,700)todateinthelowerYellowstoneRiver,wheresamplingdownstreamfromknownspawningpatcheswasintensetoverifyspawnpatchfunctionalityinvolvingreproductiveeventsforknownreproductivefemalesandpotentiallynon–telemeteredreproductivefemales.ThespawnpatchatRM5.4–6.1usedbyfemalecodes43and87hasprovenfunctionalinpastyearstosupportincubation,hatch,anddrift–entryoffreeembryos.Confirmationofpallidsturgeonfreeembryosfollowingcompletionofgenetictestingwouldsimilarlyindicatereproductivefunctionalityofthispatchunderdifferentenvironmentalconditionsin2017.Confirmationofpallidsturgeonfreeembryosfromthecode41spawningpatch(RM3.7–4.1)wouldprovideinsightintoadditionalmainstemhabitatssupportingreproduction.ThepresenceofpallidsturgeonearlylifestagesfromthePowderRiverwouldyieldinitialverificationofsuccessfulincubation,hatch,anddrift–entryfromatributaryoftheupperMissouriRiverbasin.
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BRAATEN_TABLE 1. Dates and attributes of wild and hatchery-origin pallid sturgeon detected at Intake Dam, detected in the high-flow side channel, or translocated around Intake Dam. Apex data denote the date, river, and river mile where the fish was detected upstream from Intake Dam.
Origin Code Sex Intake Dam
High Flow Side Channel
(downstream) High Flow Side
Channel (upstream) Translocation Migration
Apex Apex River Apex RM
Wild 11 Male May 13, June 14 May 14 June 1 Powder 88.1 49 Male August 8 June 6 June 8 July 10-13 Yellowstone 99.1 57 Male May 17 61 Male June 14-July 10 June 8 June 8, 9, 10 June 13 Yellowstone 75.0 83 Male May 6-8, June 20 May 8 June 1 Powder 89.9 Hatchery 1 54 Female April 22, 25; June 15 May 6 May 10 Yellowstone 84.5 2 62 Male May 13, 14, 15, 20 66 Unknown May 24, July 13 June 11, 12 June 13 June 20 Yellowstone 76.1 3 68 Unknown May 4, 8, 9, 10, 15 72 Unknown April 7-11, several
dates April 13-July 27
90 Unknown May 12 91 Male April 3-5, several
dates April 10-24, May 1-10
May 10 June 9 Powder 97.0
4 98 Male August 18-20 117 Unknown July 4-6 124 Unknown July 25 5 140 Unknown Sept 11-13; Sept 15-
Oct 17
154 Unknown May 18-20, several dates
May 23-July 2
6 155 Unknown July 13, 14; several dates July 16-Sept 6
June 13, 16, 28
7 160 Unknown May 15, August 20 May 15 May 16 July 20 Yellowstone 123.4 169 Unknown May 2-6, August 13 May 9 June 13 Yellowstone 83.4 1 No eggs were detected by BOR personnel when captured for translocation on May 6 2017, 2Implanted with transmitter on May 3 2017 at RM 6.6 of the Yellowstone River, 3Implanted with transmitter on April 26 2017 at RM 70.9 of the Yellowstone River, 4 Implanted with transmitter May 16 2017 at RM 1,710.5 of the Missouri River, 5 Implanted with transmitter on September 5 2017 at RM 65.5 of the Yellowstone River, 6 Implanted with transmitter on May 3 2017 at RM 69.1 of the Yellowstone River, 7 Implanted with transmitter on April 17 2017 at RM 67.8 of the Yellowstone River
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BRAATEN_TABLE 2. Samples and numbers of Acipenseriformes eggs, embryos, free embryos, and larvae sampled in the Yellowstone and Powder Rivers by date during June 2017.
Date Location Samples Acipenseriform eggs
and embryos Acipenseriform free embryos and larvae
6/7/2017 Yellowstone River 8 15 11 6/8/2017 Yellowstone River 4 14 7 6/9/2017 Yellowstone River 10 31 16
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Braaten_Figure 2. Percentage of telemetered wild pallid sturgeon in the Yellowstone River and corresponding discharge, April – September 2017.
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EXPLANATION
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Braaten_Figure 4. Aggregations of telemetered male pallid sturgeon by river mile location and date in the Yellowstone River, May–June 2017.
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Braaten_Figure 5. Migrations and locations of reproductive wild female pallid sturgeon codes 43, 87, 41, and 127 by date in the Yellowstone River during 2017, and corresponding discharge and temperature conditions.
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Title:Effectofwatervelocityongrowth,survival,andenergyreservesofendogenousPallidSturgeonScaphirhynchusalbuslarvae
Authors:JosephT.Mrnak,StevenR.Chipps,andDanielA.James
PallidSturgeon(Scaphirhynchusalbus)areafederallyendangeredspeciesendemictotheMissouriRiverbasinandthelowerMississippiRiver.Thelarvalphaseoffreshwaterfishesisoftencharacterizedbyhighmortality.Aswithmanyfishes,therecruitmentbottleneckforPallidSturgeonisbelievedtooccurduringtheirearlylifehistory.WatervelocityisbelievedtoplayanimportantroleinaffectingdispersalandsurvivalofendogenousPallidSturgeonlarvaeintheMissouriRiver.LarvalPallidSturgeonrequirealoticenvironmentaswellasaconnectedriversystemtocompletetheirendogenous-driftingphaseofdevelopment(Braatenetal.2008).Further,larvalPallidSturgeonrequirelongermigrationdistances,driftatfasterrates,andrequirealongerdurationtoswitchfromendogenoustoexogenousfeedingthanthesympatricShovelnoseSturgeon(Scaphirhynchusplatorynchus;Kynardetal.2002;Braatenetal2008).ThesedifferencesmayexplainwhyShovelnoseSturgeonaredoingwellwithintheMissouriRiverwhilePallidSturgeonarefacingreproductionandrecruitmentfailures.UnderstandingfactorsthataffectsurvivalofPallidSturgeonlarvaeiskeygiventheircriticalstatusandongoingrecoveryefforts.
Insummer2017,weevaluatedtheeffectsofwatervelocityongrowth,survival,andenergyreservesofendogenousPallidSturgeonlarvae(<18mmTL)usingamicrocosmexperiment.Oursystemwascomprisedoftwelve115Lovalstudytanks(Figure1)wherefishwereheldatasimilarwatertemperature(±SD)of16.3±0.3°C.Wetestedthreewatervelocitytreatments(fourreplicatespertreatment)characterizedasnovelocity(0cm/s−1),intermediatevelocity(range,1to7cm/s−1),orhighvelocity(2to16cm/s−1).
Totalenergycontentofthelarvae(J/gwetweight)wasmeasuredattwo-dayintervalsusingaParrmicro-bombcalorimeter.WerecordedtotallengthandmortalityofPallidlarvaefrom3to10dayspost-hatch.WeusedanalysisofcovariancetotestfordifferencesingrowthorenergyreservesovertimeandaTukeymultiplecomparisontestwasusedtoevaluatedifferencesinmortality.
GrowthrateofPallidSturgeonlarvaewassimilaracrosswatervelocities,rangingfrom0.76to0.84mm/d.However,energyreservesofPallidSturgeonlarvaemaintainedinthenovelocitytreatmentdeclinedsignificantlycomparedtolarvaeintheintermediateandhighvelocities.Moreover,larvaeinthenovelocitytreatmentexperiencedsignificantlygreatermortalitythatthosemaintainedintankswithflow(Figure2).Innaturalenvironments,areaswithnoflowmayposeasignificantsourceofmortalitytoendogenousPallidSturgeonlarvae.
In2018,additionalexperimentswillbeconductedtoevaluatethecombinedeffectsofwatertemperatureandvelocityongrowth,energyreserves,settlingtime,andmortalityofendogenousPallidSturgeonlarvae.
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Figure1.Schematicofthetankdesignusedinthisstudy.Notetheexternalpump(blackbox;lower-right)whichisconnectedtoacontrollablevalve(notpictured;usedtomanipulatevelocity)leadingtoourflowapparatus(PVCwithoutflowholes).Thestandpipehasholesdrilledinittopromotecirculationthroughoutthesystemwiththescreenbufferactingtoincreasethesurfaceareaaroundtheoutflowholes(sothatthelarvaedonotbecomestucktothem).Notpicturedisthe400Lbaththatcontainedtwoovaltanks,twobioreactors,andtwoaerators.
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Figure2.Plotshowingmeandaysposthatch(dph)to100%mortalityforendogenousPallidSturgeon(Scaphirhynchusalbus)larvaeamongthreetreatments;novelocity,intermediatevelocity,andhighvelocity.Thenumbersabovethebarssignifythemean(±SD)andthelettersrepresentstatisticaldifferences.
Products:
Presentations
Mrnak,J.M.,S.R.Chipps,andD.A.James.2018.Effectofwatervelocityongrowth,survival,andenergyreservesofendogenousPallidSturgeon(Scaphirhynchusalbus)larvae.2018MissouriRiverNaturalResourceConference.
Mrnak,J.M.,S.R.Chipps,andD.A.James.2018.Effectofwatervelocityongrowth,survival,andenergyreservesofendogenousPallidSturgeon(Scaphirhynchusalbus)larvae.2018UpperBasinPallidSturgeonWorkGroup.
Mrnak,J.M.,S.R.Chipps,andD.A.James.2018.Effectofwatervelocityongrowth,survival,andenergyreservesofendogenousPallidSturgeon(Scaphirhynchusalbus)larvae.54thAnnualMeetingoftheDakotaChapteroftheAmericanFisheriesSociety.
Awards
RobertA.KlumbMemorialScholarship,54thAnnualMeetingoftheDakotaChapteroftheAmericanFisheriesSociety(2018)
RobertA.KlumbMemorialTravelGrant,2018MissouriRiverNaturalResourceConference(2018)
7.25 (0.5); A
8.5 (0.57); B
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References:
Braaten, P.J., D.B. Fuller, L.D. Holte, R.D. Lott, W. Viste, T.F. Brandt, and R.G. Legare. 2008. Driftdynamicsof larvalpallidsturgeonandshovelnosesturgeon inanaturalsidechannelof theUpperMissouriRiver,Montana.NorthAmericanJournalofFisheriesManagement28:808-826.
Kynard, B., E.Henyey, andM.Horgan. 2002.Ontogenetic behavior,migration, and social behavior ofPallidSturgeon,Scaphirhynchusalbus,andShovelnosesturgeon,S.platorynchus,withnotesontheadaptivesignificanceofbodycolor.EnvironmentalBiologyofFishes63:389-403.
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GenotypicAnalysesandParentalIdentificationsofJuvenileand
Sub-adultPallidSturgeonintheMissouriRiver
FY2017Report
February28,2018
[email protected],[email protected]
U.S.FishandWildlifeServiceNortheastFisheryCenter
227WashingtonAve.,PO.Box75Lamar,PA16848(570)726-4995
Submittedto:StevenKrentz
MissouriRiverFishandWildlifeConservationOffice3425MiriamAve
Bismarck,ND58501(701)250-4419
and
PallidSturgeonRecoveryCoordinator55245NEHWY121CroftonNE68730
Billings,MT59101(402)-667-2884
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Introduction
Pallidsturgeon(Scaphirhynchusalbus)areendangeredthroughouttheirrangeandwerelistedundertheEndangeredSpeciesActin1990.TheprimarylimitingfactorforpallidsturgeonrecoveryintheMissouriRiverappearstobealackofnaturalrecruitmentoverthepast25-30years.Becauseofthislack(orlowlevel)ofnaturalrecruitment,stockingofhatcheryproducedpallidsturgeonjuvenileshasbeenusedtosupplementandmaintainpallidsturgeon.AdultpallidsturgeonarecapturedannuallyintheMissouriRiverandtakentofishhatcheriesforspawning,afterwhichtheyarereturnedtothecapturearea.However,thepallidsturgeonrecoveryplanrequiresthatallhatchery-producedpallidsturgeonareidentifiablebysometypeoftag.Inthepast,offspringwererearedinhatcheriesuntiltheywerelargeenoughtobemarkedwithPITtagsorotherphysicaltags.
Typicallyjuvenilesremaininhatcheriesfornearlyayearbeforetheyreachthesizeatwhichtheycanbetagged,approximately140-220mm.Pallidsturgeonarehighlyfecundandwillproduceseveralthousandoffspringinasingleyear,resultinginlargenumbersofoffspringnecessarytomaintainseparatelyuntiltaggingsize.Hatcheryspaceconstraintsoftenlimitthenumberofjuvenilepallidsturgeonthatcanberetained,resultingincullingoflargenumbersofoffspringeachyear.Inhatcheries,juvenilepallidsturgeonarealsohighlysusceptibletooutbreaksofiridovirusthatcanseverelylimitsurvival.Inordertoreducethetimerequiredtorearpallidsturgeoninhatcheriesandallowgreaternumbersofjuvenilestobereleased,theuseofMendelianinheritedgeneticmarkersisaviablealternativetophysicaltags(DeHaanetal.2005;DeHaanetal.2008).Theuseofgenetictagscangreatlyincreasethenumberofpallidsturgeonthatcanbereleasedeachyearbyallowingtheirreleaseatsmallersizes.
ThegeographicfocusofthisprojectwastheupperandmiddleMissouriRiver.TheupperMissouriRiverisdefinedastheareaupstreamofGavinsPointDaminSouthDakotaandincludingtheYellowstoneRiveranditstributaries(RPMA1andRPMA2).ThemiddleMissouriRiver(RPMA3andRPMA4)extendsdownstreamfromGavinsPointDamtotheconfluencewiththeMississippiRiver.TherewerethreemainobjectivescompletedduringFY2015.Theseobjectivesinclude:
1) Estimatethedegreeofrelatednessamongadultpallidsturgeonatfederal(national)andstatefishhatcheries(NFHandSFH,respectively)tobeusedashatcherybroodstockfortheMissouriRiverandprovidematingplansforhatcheryspawning(MilesCityStateFishHatcheryandGarrisonDamNationalFishHatchery,withGavinsPointNationalFishHatcheryasneeded)
2) Addadultpallidsturgeontothegeneticbaselinedatasetusedtodistinguishhatcheryandnaturaloriginjuveniles
3) UsethebaselinedatasettoconductspeciesIDforanyunmarkedjuvenilesturgeoncollectedintheMissouriRiveranduseparentageanalysistodetermineifunmarkedjuvenilesidentifiedaspallidsturgeonarehatcheryornaturaloriginfish
Methods
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Finclipspreservedin95%non-denaturedethanolwerecollectedbybiologistsparticipatinginmonitoringeffortsforjuvenileandadultputativepallidsturgeon.SampleswerereturnedtotheU.S.FishandWildlifeService(USFWS)NortheastFisheryCenterConservationGeneticsLabwithbiologicalinformationincludingPITtag,length,weight,samplinglocation,andsamplingdate.
DNAwasextractedusingthePurgenemethod(Qiagen,Valencia,CA).DNAconcentrationswereobtainedandconcentrationswerestandardizedforpolymerasechainreaction(PCR).DeHaanetal.(2005)identified17microsatellitelocithatcanbeusedforparentageanalysisinpallidsturgeonaswellasfordifferentiatingpallidandshovelnosesturgeon:Spl15,Spl18,Spl19,Spl26,Spl30,Spl34,Spl35,Spl36,Spl40,Spl56,Spl60,Spl101,Spl105,Spl106,Spl119,Spl158,Spl173(McQuownetal.2000).Twoadditionalloci(Spl12andSpl53(McQuownetal.2000))havebeenaddedtotheoriginalsuiteof17forstandardizationpurposeswithSouthernIllinoisUniversity,andtheywillbeusedforspeciesidentificationintheCentralLowlandsManagementUnit(CLMU)andInteriorHighlandsManagementUnit(IHMU)baselines.
Multiplexreactionswerecreatedtostreamlinetheamplificationprocess;fourpre-PCRmultiplexreactionswerecreated,with3to5lociwithineachreaction.LocusSpl26,Spl40,Spl53,andSpl105wereamplifiedseparately.LocusSpl26,Spl40,andSpl105wereaddedtooneofthemultiplexespost-PCR.LocusSpl53wasnotaddedtoamultiplexreactionandrunindividually.Forthemultiplexreactions,reagentconcentrationswerethesame.Each20uLPCRreactionconsistedof1.5�lofgenomicDNAextract,1.5XPCRbuffer(10mMTris-HCl,pH8.3;50mMKCl),3.75mMMgCl2,0.3175mMeachdNTP,0.12-0.80�Mofeachprimer(forwardprimerfluorescentlylabeled;AppliedBiosystems,FosterCity,CA),0.06unitsofTaqpolymerase(PromegaCorporation,Madison,WI),anddeionizedwateraddedtoachievethefinalvolume.SinglePCRreactions,Spl40andSpl105,were10ulPCRreactions,andeachconsistedof1.5�lofgenomicDNAextract,1.5XPCRbuffer(10mMTris-HCl,pH8.3;50mMKCl),3.75mMMgCl2,0.3175mMeachdNTP,0.12-0.24�Mofeachprimer(forwardprimerfluorescentlylabeled;AppliedBiosystems,FosterCity,CA),0.06unitsofTaqpolymerase(PromegaCorporation,Madison,WI),anddeionizedwateraddedtoachievethefinalvolume.Theamplificationcycleforallloci,exceptSpl105whichhadadifferentannealingtemperature,consistedofaninitialdenaturingat94°Cfor2min;35cyclesof94°Cdenaturingfor45sec,56°Cannealingfor45sec,72°Cextensionfor2min;anda30minextensionat72°C.LocusSpl105hadanannealingtemperatureof50°C.GenotypeswerevisualizedusinganABI3130(AppliedBiosystems,FosterCity,CA).GenescanandGenmappersoftwarefromAppliedBiosystems(FosterCity,CA)wasusedtoidentifyallelesateachofthe19loci.
Speciesidentification
Tranahetal.(2004)usedninemicrosatellitelocitodiscriminatepallidandshovelnosesturgeonintheupperMissouriRiverwithan82to95%probabilityofcorrectassignment.The17lociusedintheseanalysesincludedthelociidentifiedbyTranahetal.(2004)andadditionallocithatallowedthediscriminationbetweenpallidandshovelnosesturgeonwithahighdegreeofconfidence(DeHaanetal.2005).
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GeneticbasedspeciesassignmentsanddetectionofhybridizationwereaccomplishedusingthecomputerprogramNewHybrids(AndersonandThompson2002).ThisBayesian-basedmethodusesmarkersthatdifferinallelefrequencybutdonothavefixeddifferencesbetweenknownbaselinegroups,(suchaswithpallidandshovelnosesturgeonintheupperandmiddleMissouriRiver),andthemodelcomputestheposteriorprobabilitythateachindividualbelongstooneofthetwospeciesoroneoffourclassesofhybrids(F1’s,F2’s,andbackcrosses).Individualswereclassifiedasapallidsturgeoniftheprobabilityofassignmenttoknownpallidsturgeonwas95%orgreater,basedonmethodsdevelopedbyUSFWSAbernathyFishTechnologyCenterandinconjunctionwithDr.EdHeist(SouthernIllinoisUniversity).However,forindividualssampledinthelowerportionofthebasin(RPMA3&4),iftheprobabilityofassignmentis90%orgreater,origindeterminationisalsoconductedduetotheslightlyreducedabilitytodistinguishpallidandshovelnosesturgeonbasedonallele-frequencydifferencesbetweenbothspecies.
Hatcheryversusunknownoriginidentification
Followingspeciesidentification,geneticparentageanalysiswasusedtodetermineifapallidsturgeonoriginatedfromthehatcheryprogramorwasnaturallyproducedwithintheMissouriRiver.Multi-locusgenotypesforalmosteveryhatchery-spawnedadultsince2000havebeenobtainedat17microsatelliteloci(seeobjectives1&2),andgenotypedataarestoredinaMicrosoftAccessdatabasedevelopedandmaintainedbyNEFC.AtaggingdatabasedevelopedbyUSFWSMissouriRiverFWMAOmaintainsadditionalinformationsuchasspawningandstockinginformation,andthisdatabaseisusedtoreferencegeneticparentageassignmentstoknownspawningpairsandstockinglocations.
ParentageassignmentswereconductedusingCervus(ver3.0;Kalinowskietal.2007).Geneticparentageassignmentsoccurusingmodifiedexclusionbasedmethodallowingforasinglemismatchintheoffspring-parent-parenttriplet.Ifajuvenilefishisnotcompatibleattwoormorelociwithaparticularhatchery-spawnedpair,thenthatpairisexcludedaspotentialparentsofthatjuvenilesturgeon.DeHaanetal.(2005)determinedthatbyusing17highlyvariablelociandallowingforasinglemismatchtoaccommodateforgenotypeorlaberrors,theprobabilityofanincorrectmatchwasverylow.ParentageassignmentswerecomparedtothespawningdatabasemaintainedbyUSFWSMissouriRiverFishandWildlifeConservationOfficetoconfirmifageneticallyassignedspawningpairrepresentedaknownspawningpair.Ifthejuvenilefishwasnotassignedtoanyhatcheryparents,thentheindividualwasidentifiedasunknownorigin.Additionally,asmallnumberofbroodstockhavenotbeengenotypedandthereforearenotavailableforparentageassignment,andsomespawningrecordsareincompleteforindividualspawningpairs(oneorbothparentslistedas“unknown”or“mixture”).Thus,ifnotassignedtoadocumentedspawningpair,resultscannotbeconfirmedifafishisnotofhatcheryoriginorwildsimplybecausetheyarenotassignedtohatcheryparents.Therefore,individualsnotassignedtohatcheryfamiliesareidentifiedas“unknown”origin.
Results
Objective1–EstimatethedegreeofrelatednessamongMissouriRiverbroodstock
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Duetothelimitednumberofpallidsturgeonbroodstockavailableduringaspawningseason,geneticinformationwasusedtohelpreducethepotentialforinbreedingandtomaintaingeneticdiversityduringhatcheryproduction.Relatednessestimatesofadultpallidsturgeonbroodstockareusedtoidentifyspawningpairstoavoid;suchascrossesbetweenfullandhalfsiblings,andtoallowfortheminimumdegreeofrelatednessamongfamiliescreated.Pairwiserelatednessvalues(Rxy)weredeterminedbetweenallindividualsusingmulti-locusgenotypesforallpairsofbroodstockusingthecomputerprogramSPAGeDi(HardyandVekemans2002),basedonrelatednessalgorithmofQuellerandGoodnight(1989).
Potentialbroodstockaregenotypedat17microsatelliteloci.Forpotentialbroodstock,thespecies(pallid,shovelnose,orhybrid)wasdetermined,andforindividualsidentifiedaspallidsturgeon,origin(hatcheryorunknown)wasassessed.AmatingplanwasdevelopedforbroodstockofreproductivematurityatGarrisonDamNationalFishHatchery(GDNFH).Cryopreservedmiltfrommalespreviouslycapturedforspawningwasalsoconsideredinthespawning.
OnebroodstockreportwasprovidedduringFY2017.ThereportmadespawningrecommendationsforfourreproductivepallidsturgeonfemalesandninereproductivepallidsturgeonmalesatGDNFH(KalieandBartron2017).Also,apotentialof90pallidsturgeonmalesthathadbeenpreviouslycryopreservedatGarrisonDamNFHwerealsoincludedinthereport.Allpotentialbroodstock,includingthecryopreservedmilt,weredeterminedgeneticallytobepallidsturgeon(Table1).
Additionally,priorityscoreswerealsoassessedtoaidinfieldcollectioneffortsofbroodstockthathadnotpreviouslybeenspawnedortoavoidspawningindividualsthathadalreadycontributedoffspringtomultiplespawningevents.Thesepriorityscoresweredistributedpriortobroodstockcollectionefforts,andincorporatedupdatedretentiontargetsofcaptiveindividualsmaintainedatGavinsPointNationalFishHatcheryandupdatedspawningandcapturerecordsfromRyanWilson(USFWS).PriorityscoresareupdatedyearlybasedonrecaptureratesandretentiontargetsofcaptivebroodstockdeterminedbyGPNFH.Retentiontargetsofcaptivebroodstockwillbedeterminedonanindividualbasisratherthanafamilybasisfor2019.
Table1.Summaryresultsofthe2017broodstockanalysisbyhatchery.Speciesresultsincluded:PD(Pallid),SH(Shovelnose),HY(Hybrid),andoriginresultsincludedHatchery(HA)orunknown(UN).
Results-speciesIDResults-Origin Hatchery PD SH HY HA UN GDNFH 103***103***Includes90cryopreservedmales
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Objective2–Continuetoaddadultpallidsturgeontothegeneticbaselinedataset
Broodstockcollectioneffortsgenerallycapturemoreadultsthanareeventuallyspawnedbecausenotalladultsarereproductivelyviableinagivenspawnyear,reproductiveviabilitycannotnecessarilybedeterminedattimeofcollection,oradultswerecollectedforbroodstockuseinfutureyears.TheseadditionaladultscollectedfromtheMissouriRiverarealsogenotypedandcharacterizedforspeciesandorigindetermination.Becausetheseadditionaladultsarereturnedtotheriver,theydohavethepotentialtoreproduceinthewildinsubsequentyears.Inclusionoftheseadultsintothebaselinedatasetisusefulforfutureanalysisofnaturalreproduction.
Atotalof90additionaladultsorbroodstockweregenotypedandincludedintothegeneticbaselinefollowingspeciesandorigindetermination(Table2:Adults(AD)andBroodstock(BR)).FiveindividualsweresampledfromRPMA1,30individualsfromRPMA2,noindividualsfromRPMA3,and55individualsweresampledfromRPMA4.Speciesidentificationwasfirstperformedtodetermineifsamplesreceivedwerefrompallidsturgeon,shovelnosesturgeon,orahybridbetweenpallidandshovelnose.Ofthe90samplesanalyzed,88wereidentifiedtobepallidsturgeon,zeroindividualswereidentifiedasshovelnose,and2wereidentifiedtobehybrids.Ofthe88pallidsturgeonidentified,40wereofhatcheryoriginand48wereofunknownorigin(Table2).
Table2.SummaryofthesamplesreceivedduringFY2017forgeneticanalysis,byRPMA,lifestage,species,andoriginfortheadult(AD)andbroodstock(BR)samples.BroodstocksamplesfromTable1arenotincludedintheadultcount.Speciesresultsincludepallid(PA),shovelnose(SH),hybrid(HY),andunknown(UN).Originwascalculatedforindividualsidentifiedaspallidsturgeon,andwaseitherhatchery(HA)orunknown(UN). Lifestage Species Origin RPMA AD BR PA SH HY HA UN 1 4 1 5 0 0 4 12 20 10 30 0 017133 0 0 0 0 0 0 04 5 50 53 0 21934 Total 29 61 88 0 24048
Objective 3 – Conduct genetic parentage analysis for unknown juvenile pallid sturgeon to
determine hatchery vs. natural origin
Atotalof314putativepallidsturgeonsampleswereprovidedfromlarvae,young-of-year,or
juvenilesforspeciesandorigindetermination(Table3).ThisdoesnotincludeProject3.7 samplesor
captiveoffspring.TwoindividualsofthissizeclassweresampledfromRPMA1,77individualswere
sampledfromRPMA2,23individualsweresampledfromRPMA3,and212sampleswerefromRPMA4.
Geneticspeciesidentificationwasfirstperformedtodetermineifsamplesreceivedwerefrompallid
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sturgeon,shovelnosesturgeon,orahybridbetweenpallidandshovelnose.Parentageanalysiswasalso
determinedforallpallidsturgeon.Ofthe314samplesprovided,atotalof247pallidsturgeonwere
identified,41weredeterminedtobeashovelnosesturgeon,17weredeterminedtobehybrids,2
individualsweretriploid,and7individualsdidnotamplify.Allhybrid,triploid,andnon-amplifying
individualswerefromRPMA4.Ofthe247samplesidentifiedtobepallidsturgeon,235wereof
hatcheryoriginand12wereofunknownorigin(Table3).Resultsfromallsamplesreceivedwere
providedtothebiologist(s)whocollectedandsentthesample.
Table3.SummaryofthesamplesreceivedduringFY2017forgeneticanalysis,byRPMA,lifestage,species,andoriginforthelarvae(Lar),young-of-year(YOY),andjuvenile(JU)samples.Speciesresultsincludepallid(PA),shovelnose(SH),hybrid(HY),andunknown(UN).Originwascalculatedforindividualsidentifiedaspallidsturgeon,andwaseitherhatchery(HA)orunknown(UN). LifestageSpeciesOrigin RPMA Lar YOY JU PA SH HYTriploid/NoAmp. HA UN 1 0 0 2 2 0 0 0202 03047 4631 004603 0 023 23 0 002304 01220017610179164 12 Total 0422722474117923512IncontinuingwithinheritancetestingofcaptiveoffspringatGavinsPointNationalFishHatchery,73pallidsturgeonwerealsoanalyzedin2017(Table4).72hatcherycrosseswereconfirmed.1individualwastriploidandcouldnotbeanalyzed.Thetriploidsamplewasfrom2016.
Table4.SummaryofcaptiveoffspringsamplesreceivedduringFY2017forgeneticanalysisbyGPNFHbyyearclass,numberofindividualsperyearclass,confirmedhatcherycrosses,andtriploidindividuals. YearClass #IndividualsYearClass#Confirmedhatcherycrosses#Triploidindividuals201533330201640391
GeneticanalysisofunmarkedpallidsturgeoninRPMA1and2(Project3.7)wasalsocompletedwithsupplementalfundingbyMontanaFishWildlifeandParks.301individualswereanalyzedforspeciesidentificationandhatcheryvsunknownoriginidentification(Table5).194sampleswerecollectedinRPMA1,and107sampleswerecollectedinRPMA2.Allsamplesweredeterminedtobepallidsturgeonandhatcheryorigin.Therewere75differentfamiliesand16differentyearclassesrepresentedfromthe301hatcheryoriginindividualscollectedinRPMA1and2in2017(Table6).
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Table5.SummaryoftheProject3.7samplesreceivedduringFY2017forgeneticanalysis,byRPMA,lifestage,species,andoriginforjuvenile(JU)samples.Speciesresultsincludepallid(PA),shovelnose(SH),hybrid(HY),andunknown(UN).Originwascalculatedforindividualsidentifiedaspallidsturgeon,andwaseitherhatchery(HA)orunknown(UN). LifestageSpecies____Origin RPMAJUAD PA SH HYTriploidHAUN 11931 194000194021070107 0 001070____Total 30013010003010
Table6.2017Project3.7samplesbrokedownbyRPMAandyearclass.
RPMA FamilyFemale FamilyMale YearClass#IndividualsYear
Class1 1F4A301354 7F7D291A07 1997 11 132213574A 1F482F3F2B 2005 21 4443240458 444334021A 2005 21 1F497F1801 1F4A0B1A72 2006 21 1F497F1801 1F4A3E1445 2006 11 1F497F1801 444171072D 2006 41 1F497F1801 466C473C59 2006 21 115557165A 1F47760123 2007 21 115557165A 431565767B 2007 11 115557165A 7F7D291A07 2007 11 1F4A436E66 115631222A 2007 21 454B380D60 2204583665 2007 11 470378405D 1F4B26036D 2007 11 47151A3D3A 115669294A 2007 11 47151A3D3A 7F7D372A6B 2007 11 7F7FD66963 115525534A 20072009 41 115557463A 220E5E551E 2008 21 115557463A 4310556551 2008 11 115557463A 444334021A 2008 31 1F497F1801 115712453A 2008 11 1F497F1801 1F4849755B 2008 21 1F497F1801 7F7D2D723D 2008 21 1F497F1801 7F7F066471 2008 11 470A675627 7F7E55466D 2008 11 470A675627 7F7F066471 2008 21 7F7F066452 7F7D437250 2008 41 115557165A 115679523A 2009 1
87
1 115557165A 470A754E14 2009 51 115557165A 7F7D365422 2009 111 115557165A 7F7F06697C 2009 101 1F4848153C 1F4A555072 2009 11 1F4848153C 424E680B49 2009 11 220F01755C 43105C602B 2009 31 220F01755C 4704550E5B 2009 61 220F01755C 7F7D37642C 2009 41 4315327C7B 4718447879 2009 21 454B490528 1F477B3A65 2009 21 454B490528 435F71414F 2009 21 454B490528 44440A7B73 2009 11 470468383C 1F4A13453F 2009 21 470468383C 47037F3026 2009 31 470468383C 7F7B023408 2009 31 7F7FD66963 220E4E4E5D 2009 31 7F7FD66963 465B6F1939 2009 61 1F5569653E 132313521A 2010 11 1F5569653E 1F4A33194B 2010 41 1F5569653E 7F7D24754C 2010 31 43105F0C7E 1F4A143350 2010 51 43105F0C7E 44436E2975 2010 21 43105F0C7E 4704550E5B 2010 61 6C00024873 116165646A 2010 31 486A080614 7F7B024F2D 2012 11 462C7B2F49 1F4A435004 2013 21 462C7B2F49 1F4B225A1A 2013 91 462C7B2F49 487F4B1745 2013 11 7F7D517479 486838404F 2014 101 7F7D517479 7F7D433241 2014 41 1F48421542 115556461A 2015 91 1F48421542 1F53312736 2015 51 1F48421542 7F7D376F73 2015 121 470378405D 220F0E6207 2016 11 470378405D 220F107A6F 2016 21 7F7D517479 7F7D7C2447 2016 12 220E345E09 1F4A111C6A 2001 22 220E345E09 1F4A27214F 2001 22 116224546A 1F477B3A65 2002 12 116224546A 220F107A6F 2002 102 116224546A 452A4E1F15 2002 12 7F7F054855 115669540A 2003 12 115557165A 1F50072169 2005 1
88
2 4443240458 444334021A 2005 22 1F497F1801 1F4A0B1A72 2006 82 1F497F1801 1F4A3E1445 2006 52 1F497F1801 444171072D 2006 32 1F497F1801 466C473C59 2006 32 115553544A 115556461A 2007 12 115553544A 4441774C6E 2007 12 115557165A 7F7D291A07 2007 12 47151A3D3A 115669294A 2007 12 7F7FD66963 115525534A 2007,2009 22 115557463A 220E5E551E 2008 12 115557463A 4310556551 2008 12 1F497F1801 115712453A 2008 42 1F497F1801 1F4849755B 2008 22 1F497F1801 7F7D2D723D 2008 12 1F497F1801 7F7F066471 2008 12 470A675627 115626162A 2008 32 470A675627 7F7F066471 2008 22 115557165A 115679523A 2009 22 115557165A 7F7D365422 2009 12 115557165A 7F7F06697C 2009 22 220F01755C 43105C602B 2009 42 220F01755C 4704550E5B 2009 62 220F01755C 7F7D37642C 2009 112 4315327C7B 7F7B082C10 2009 12 454B490528 1F477B3A65 2009 12 470468383C 47037F3026 2009 22 7F7FD66963 465B6F1939 2009 12 1F5569653E 132313521A 2010 12 1F5569653E 1F4A33194B 2010 12 1F5569653E 7F7D24754C 2010 42 43105F0C7E 4704550E5B 2010 12 6C00024873 116165646A 2010 12 7F7D517479 486838404F 2014 12 1F48421542 115556461A 2015 12 1F48421542 1F53312736 2015 32 1F48421542 7F7D376F73 2015 22 4A46717168 7F7D23292E 2017 1
89
In2017,standardizationandupdatingofbaselinesfortheCentralLowlandsManagementUnitandInteriorHighlandsManagementUnitcontinuedincollaborationwithDr.EdHeistfromSouthernIllinoisUniversity.Wecomparegenotypes(QAQC)onallindividualsaddedtothesebaselines.
Additionalanalyses
WealsoanalyzedjuvenilescollectedaspartoftheevaluationofalarvaldriftstudyconductedbytheUpperBasinWorkgroupmembersin2016.Thestudyreleased~700,0001-dph(daysposthatch)PallidSturgeonfreeembryosintheMissouriRiverneartheMilkRiverconfluencetoevaluatedriftdynamics.In2017,aspartofthejuvenilesamplingeffort,onejuvenilesample(Sturg-10965/PITtag6C00097722)wasdeterminedtobefromthe2016MissouriRiverPallidSturgeonFreeEmbryoDriftStudy.Itwascollectedon8/25/2017byMRFWMAO.Geneticresultsconfirmedthisindividualoriginatedfromfamilycross1F497F1801x0A180E0E7Espawnedon6/21/2016.Thisfamilycrosswasspawnedspecificallyforthelarvaldriftstudyanditsoffspringwerestockedoutonlyforthestudypurposeon6/27/2016.
Alsoin2017,TheUSFWSNortheastFisheryCenter(NEFC)ConservationGeneticsLabinLamar,PAreceivedtwentytwovialsofpallidsturgeoneggs(~20pervial)fromWarmSpringsFishTechCenter(WSFTC)onAugust30,2017.Eggsfromdifferentfamilygroupsresultingfrommalesthatwerecryopreservedusingdifferentmethodswerepreservedforassessmentofreproductivestatus.However,therewasconcernthatthetubelabelsmaynothavereflectedthecross(andpreservationmethod),andsothemaleparentcontributingtoeachfamilyandgroupofeggswasunknown.Withoutdeterminationofthemaleparent,thenthesuccessofthevariouscryopreservationmethodscouldnotbeassessed.
Followingreceiptofthevials,DNAwasisolatedfromtheeggsusingaPurgeneDNAextractionprotocol(Qiagen,Valencia,CA).DNAwasthendilutedwithanequalvolumeofreagentgradesterilewater.PolymeraseChainReaction(PCR)wasthenperformedon96samples(4-6eggsfromeachvial)at19lociandgenotypesforthefullsuiteoflociwereacquired.Thegeneticresultsindicatedthatthetubesweremislabeledforvials1through10.Geneticresultsalsoindicatedvial6containedeggsfertilizedbytwocryopreservedmalesusedinthestudy.Vials11through22matchedthelabelingonthevialsforfamilycross.ResultswereprovidedtoWSFTCsotheycouldcompletetheevaluationofcryopreservationmethod.
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References
Anderson,E.C.andE.A.Thompson.2002.AModel-BasedMethodforIdentifyingSpeciesHybridsUsingMultilocusGeneticData.Genetics160:1217–1229.Banks,M.A.andEichert,W.2000.WHICHRUN(version3.2):Acomputerprogramforpopulationassignmentofindividualsbasedonmultilocusgenotypedata.JournalofHeredity91:87-89.DeHaanP.W.,D.E.Campton,andW.R.Ardren.2005.Genotypicanalysisandparentalidentificationofhatchery-originpallidsturgeonintheUpperMissouriRiver:PhaseIInheritanceofMicrosatellite,NuclearDNAMarkers.June23rd,2005.35pp.USFWSAbernathyFishTechnologyCenterFinalReport.DeHaanP.W.,G.R.Jordan,andW.R.Ardren.2008.Useofgenetictagstoidentifycaptive-bredpallidsturgeon(Scaphirhynchusalbus)inthewild:improvingabundanceestimatesforanendangeredspecies.ConservationGenetics9:691-697.GoodknightK.F.andQuellerD.C.1999.Computersoftwareforperforminglikelihoodtestsofpedigreerelationshipusinggeneticmarkers.MolecularEcology8:1231-1234.Kalie,J.andM.L.Bartron.2017.2017MatingPlanforUpperMissouriRiverPallidSturgeonBroodstock:GarrisonDamNationalFishHatchery.June27,2017,providedtoGarrisonDamNationalFishHatcheryMcQuown,E.C.,Sloss,B.L.,Sheehan,R.J.,Rodzen,J.Tranah,G.J.andMay,B.2000.Microsatelliteanalysisofgeneticvariationinsturgeon:newprimersequencesforscaphirhynchusandacipenser.TransactionsoftheAmericanFisheriesSociety129:130-1388.QuellerD.C.andGoodnightK.F.1989.Estimatingrelatednessusinggeneticmarkers.Evolution43:258–275.Snyder,D.E.2002.Pallidandshovelnosesturgeonlarvae–morphologicaldescriptionandidentification.JournalofAppliedIchthyology18:240-265.Tranah,G.,D.E.Campton,andB.May.2004.Geneticevidenceofhybridizationofpallidandshovelnosesturgeon.JournalofHeredity95:474-480.
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EXAMINATIONOFPALLIDSTURGEON(Scaphirhynchusalbus)LARVALDRIFT,DEVELOPMENT,
ANDSWIMMINGABILITIES
FinalreportSubmittedby
DavidRussellDockeryWildRiversConsultingLivingston,MT59047
KevinM.KappenmanU.S.FishandWildlifeService
BozemanFishTechnologyCenterBozeman,MT59715
March2018
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ACKNOWLEDGEMENTSIwouldliketothanktheBozemanFishTechnologyCenter,UpperBasinPallidSturgeon
WorkgroupandWesternAreaPowerfortheirsupport,selectionandfundingofthestudy.Iwouldliketothankallthescientiststhathavedevotedtheirtimeandlivestopallidsturgeonrecovery.Thequalityandquantityofpreviousresearch,thesynthesisofknowledge,andthecollaborationamongcolleaguesisinspiring.Thisprojectwasmadepossiblebythecollaborationandsupportofmultipleagenciesandindividuals.WewouldliketothankGavinsPointNationalFishHatchery,JeffreyPowell,ChrisHooley,andstaffforspawningfishandprovidingeggsandtheMissouriRiverNaturalResourcesCommitteeforhelpwithfundingandcontracting.Theprojectwouldnothavebeenpossiblewithoutthehardwork,support,andpatienceofBenHendrickson,ChristerWheat,andKevinKappenman.JasonIlgenisthankedforhishelpandexpertise.
EXECUTIVESUMMARY
Sustainablepallidsturgeonnaturalrecruitmenthasnotbeenobservedsincetheidentificationofthespecies.Mortalityassociatedwithanextendedlarvaldriftphaseofdevelopmentisattributedtoanalmostcompletelackofobservedrecruitmentinthelast50years.Larvaearehypothesizedtodriftintoreservoirhabitatandsettleinananoxicbottomlayer,resultinginmortality.Debateexistsonlarvaldriftbehavior,durationanddistance.Toassesscurrenthypotheses,wemeasuredtherelationsamonglarvaldevelopment,settlingbehavior,velocity,temperature,andhabitat.Weobservedastrongrelationshipbetweentemperatureanddevelopment,withmostembryosobservedtransitioningtoactivelyfeedinglarvaeby23daysposthatch(dph)at15°Ccomparedto13dphat20°C.Mostembryosdevelopedbottomsettlingbehaviorat9dphat20°Cand~13dphat15°C.However,embryos/larvaecycledbetweendriftandbottomorientationuntil30dphin0.61mdiametercirculartanksand71dphinalargeovalartificialriver(20mcircumference).Swimmingstudiesindicatedthatlarvaeareweakswimmersandbottomvelocitiesofselectedsettlementareas(<15cm/s)approximatedmaximumsustainedswimmingvelocities.Flatsmoothsubstrateswereselectedandfoodavailabilityappearedtoaffectdistribution.Competitionappearedtocontributetoextendeddrift.Basedonobservations,wehypothesizethedriftphaseofdevelopmentwillbeextendedifsuitablerearinghabitatisnotavailable.Dammanagementpracticesthataimtorestorenaturaltemperatureregimesandincreasetemperatureofreleasedwaterwillgreatlydecreasedriftdurationanddistances.Weobservednoevidencethatflowmanipulationwillaffectlarvaldevelopmentrates,butitwillcertainlyaffectdriftspeed,driftdistances,andhabitatavailability.
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EXAMINATIONOFPALLIDSTURGEON(Scaphirhynchusalbus)LARVALDEVELOPMENT,
BEHAVIORANDSWIMMINGABILITIES
INTRODUCTION
Sturgeon(Acipenseridae)originated200-250millionyearsagoandremainonetheoldestextantfamilyofspecies(Carmonaetal.,2009).Despitesurvivingmultiplemassextinctioneventsandglaciation/deglaciationeventsthatdramaticallychangedthelentic,lotic,andmarinelandscapes,26ofthe27extantspeciesofsturgeonarenowlistedasvulnerable,endangered,orcriticallyendangered(BillardandLecointre,2001;LorkeandYew,2005;Carmonaetal.,2009).Pallidsturgeon(Scaphirhynchusalbus)areamongtherarestsurvivingfishspeciesinNorthAmerica(Kallemeyn,1983).
PallidsturgeonareendemictotheMissouriandMississippiRiversandsomeoftheirlargertributariesandwerefirstidentifiedin1905asaseparatespeciesthanshovelnosesturgeon(Scaphirhynchusplatorhynchus),asympatriccongener(ForbesandRichardson,1905).Littlewasknownaboutpallidsturgeonuntilthelate20thcenturyandearlyreportsfromcommercialharvestindicatethattheywererelativelyrarecomparedtoshovelnose,oftenlessthan10%ofthecatchofriversturgeon,andweremostfrequentlyobservedintheupperreachesoftheMissouriintheDakotasandMontana(ForbesandRichardson;1905,BaileyandCross,1954;DryerandSandvol,1993).Commercialharvestandpollutionareassociatedwithinitialdeclinesofriversturgeon,witha10folddeclineinharvestmassobservedbetweenthe1890’sand1950(Carlander,1954;WhitleyandCampbell,1974).However,harvestintheUpperMissouriwaslikelynegligibleornonexistentandnowfewerthan175naturallyproducedpallidsturgeonareestimatedtoliveintheUpperMissouriBasinaboveLakeSakakaweainNorthDakota(Kallemeyn,1983;DryerandSandvol,1993;USFWS,2014).SurvivingwildsturgeonintheUpperMissouriRiverBasinareestimatedtobeatleast44yearsold(Braatenetal.,2009).
DammingoftheMissouriRiverbeganin1926andsixlargemainstemdamswerebuiltby1952(DryerandSandvol,1993).Extirpationanddeclineoflocalshovelnosesturgeonpopulationswasnotedbythemid-20thcenturyandassociatedwithdamming(BaileyandCross,1954).Damscanbedamagingtolargeriverspeciesbecausetheyfragment,inundateandeliminatecriticalhabitat,isolatepopulations,alterflowandtemperatureregimesandreducesedimenttransport,turbidity,naturalchanneldevelopmentandfloodplainconnectivity/productivity(BaileyandCross,1954;DryerandSandvol,1993;Nilssonetal.,2005).Allhistoricalpallidsturgeonhabitathasalteredflowregimes,36%ofhistoricalpallidsturgeonhabitathasbeeneliminated,and40%hasbeenchannelized(DryerandSandvol,
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1993).Becauseofanextendedlarvaldriftphaseofembryonicdevelopment,pallidsturgeonareparticularlysusceptibletohabitatfragmentation(Kynardetal.,2002,2007).
DespiteevidenceofsuccessfulspawningofpallidsturgeonintheUpperMissouriBasin(USGS,2007;Fulleretal.,2008;DeLonayetal.,2016),evidenceofnaturalrecruitmenthasbeenextremelyrareforalmost50years,suggestingarecruitmentbottleneckduringembryonicdevelopment(USFWS,2000;FullerandHaddix,2012;Braatenetal.,2008,2012a;Guyetal.,2015).Pallidsturgeonembryosexhibitaswimupanddriftdispersalbehaviorafterhatchinguntil~9-11daysposthatch(dph;temperaturedependent),whenlarvaebeginexogenouslyfeedingandareassumedtosettleonthebottom(Conteetal.,1988;Kynardetal.,2002,2007).
Estimatesofdriftdistancesfromlaboratoryandfieldexperimentssuggesttheremainingsegmentsoffree-flowingMissouriRiverarenotlongenoughforembryostodevelopandtheylikelyendupinreservoirsortransitionzonesbetweenriversandreservoirs(Kynardetal.,2002,2007;Braatenetal.,2008,2010,2012a).Fieldstudiesidentifiedanoxicconditionsnearthebottomintransitionzonesbetweenriversandreservoirsthatresultedinembryonicdeathwithinanhourwhenreplicatedinalaboratory;apparentlyidentifyingthecauseofrecruitmentbottleneck(Guyetal.,2015).However,skepticsofthishypothesisnotethatthevastmajorityofembryos/larvaeinriverdriftstudiesarenotrecoveredandtheirbehaviorinrelativelysimplelaboratoryenvironmentsmaynottranslatetothecomplexhydraulicenvironmentsoflargerivers(Braatenetal.2008,2010,2012a;MarotzandLorang,2017).Additionally,detailedflowmappinganddriftmodellingindicatetheUpperMissouriisverydispersivetoparticlesandhasmanyretentionareasthatshouldprovideembryosenoughtimetodevelop(MarotzandLorang,2017).
Thepurposeofthisstudywastoexaminetheeffectsofabioticfactorsonlarvaldevelopmentandbehaviorinordertobetterinformdammanagementandreassessthecurrentlarvaldrifthypothesis.Theeffectsoftemperatureandvelocityonlarvaldevelopmentwereexaminedinsmallcircularchannels.Habitatselectionandlarvalbehaviorwereexaminedinalargeartificialriverwithacomplexhydraulicenvironmentandadiversityofsubstratesandhabitats.Larvaewereobservedafterexogenousfeedingbegantoidentify‘post-settling’behavior.Additionally,swimmingabilitiesoflarvaewereexaminedtoallowinferencetosuitablebottomvelocitiesforsettlinglarvae.Whileextensivestockinghassustainedthespecies,theultimategoalofanaturallyreproducingandpropagatingspeciesisoutofreachuntilthefactorscontributingtothelackofrecruitmentarebetterunderstood(USFWS,2000;USFWS,2008).
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METHODS
TESTFISHANDFACILITIES
Freeembryosusedinexperimentswerefromtwodistinctspawningeventsandparentage.EggswerecollectedfrompallidsturgeonheldatGavinsPointNationalFishHatchery(GPNFH;Yankton,SouthDakota,U.S.)andspawnedon25May2017and13June2017.Inbothspawningeventseggswerehandstrippedfromthreefemalesandpairedwithspermfromthreemalestoprovidethreecrosses.Eggswerefertilizedat16.9°Candstirredwithamixtureofbentoniteclayandwaterfor20mintoeliminateadhesiveness(VanEenennaametal.,2001).FertilizedeggsweretransportedinaninsulatedcoolerfromGPNFHtotheBozemanFishTechnologyCenter(BFTC;Bozeman,Montana,U.S.).TemperatureduringtransportwasmonitoredwithanErtcoHighPrecisionThermometer(BarnsteadInternational,Dubuque,Iowa)andvariedlessthan1.0°Cfromthetemperatureatthetimeoffertilization(16.9°C).UponarrivalattheBFTC,eggsfromallcrosseswerethoroughlymixedandtreatedwiththedisinfectantOvadine(BufferedPVPIodine;10mL/L)for10min.Eggswereacclimatedtoincubatingtemperaturesbyplacingbagsinawaterbathandgraduallyaddingwatertoreachthedesiredtemperature(±0.5°Cevery20min).Alleggsfromthefirstspawningeventwereincubatedat16.1±1.0°Cwhereaseggsfromthesecondspawningeventweresplitandincubatedattwowatertemperatures:15.5±0.5°Cand20.5±0.5°C.
Eggswereincubatedin0.5LMcDonaldjarsprovidedwithflowthroughwater(0.15–0.2L/min).Waterfromon-sitewarmandcoldspringswasmixedtoobtainthedesiredtemperatureandcontinuouslypassedthroughapacked-columndegassingsystem.Thedegassingsystemremovedsupersaturatednitrogen,reducedtotaldissolvedgaslevels,andmaintainedgaslevelsatacceptablerearingcriteriaforaquaticspecies(Kappenmanetal.,2013).Averagedissolvedoxygenwas7.24and7.07mg/Lat15and20°C,respectively.Watertemperatureandcumulativethermalunits(CTU)wererecordedhourlythroughoutallexperimentswithOpticStowawayTempDataLoggers(OnsetComputerCorporation,Bourne,Maine,U.S.).Aphotoperiodof12:12hwasmaintainedwithoverheadlightingthroughoutallexperimentsandwassupplementedwithnaturallightfromwindows.Unfertilized,fungused,anddeadeggswereremovedfromjarsatregularintervals.
HatchedfreeembryosswamupandoutofMcDonaldjarsinto1.8mcircularholdingtanks,wheretheywereheldforamaximumof12hrsbeforebeingassignedtoanexperiment.
Daysposthatch(dph)wereusedtoquantifyage,withthedayofhatchreferredtoas0dph.Sturgeoninthisstudywereclassifiedasfreeembryosfromhatchuntilthetimeofactivefeedingandlarvaethereafter(Balon,1999).Fiftyfreeembryosfromeachtemperaturetreatmentweresampledonthedayofhatchtoassesslengthathatch.Freeembryoswerefirst
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presentedOtohimeFishDiet(ReedMariculture,Campbell,California,U.S.)at7dph.Feedparticlesize(range:250-1410µm;B1,B2,C1,C2)wasincreasedbasedonfishsize.Larvaeheldinthesmall0.61mdiametercirculartanksusedtoexaminetheeffectsoftemperatureandvelocity(“Velocity×Temperature”experiment)werefedtwicedailywithenoughfoodtoensureexcesswascontinuouslypresentonthebottom.Feedwascontinuouslypresentedtolarvaeinlargertanksusingautomatedbeltfeeders.Tankswerecleaneddaily.Freeembryos/larvaesampledfromexperimentswereeuthanizedwithananestheticoverdose(MS222,50mg/L),photographed(NikonD750,AFMicroNikkor60mmlens)onametricruler,andstoredinHistoPrep100%alcohol(FisherScientificCompany,Denver,Colorado).PhotographswerelateranalyzedusingImageJ(version1.50i,Bethesda,Maryland)tomeasurelength,yolksacarea,fincurl,andpresence/absenceofmelaninplugandfood.
Totallengthwasmeasuredfromthetipofthetailtotheanteriortipofthehead(Fig.12)forfishthathadnotdevelopedacaudalfilament(approximately<20.0mm)androundedto0.1mm.Forfishwithcaudalfilaments,totallengthwasmeasuredfromtheposteriorendofthenotochordtoanteriortipofthenose.Theendofthenotochordwasapproximatedifnecessarybythepointatwhichtheventralmarginofthecaudalfinmembranestopsconvergingonthenotochordandbeginstorunparalleltothecoreofthecaudalfilament(Snyder2002).Therelationshipbetweenlengthanddphwasusedtodescribegrowthrate.Yolksacareawasmeasuredtothenearest0.01mm2fromphotographsofthelateralviewoffreeembryos.Yolksacareawasonlyrecordedwhentheyolksaccouldbeclearlydistinguishedandlipidswereexcludedfromthemeasurements.Theyolksacwasconsideredtobeabsorbedwhenitwasnolongerexternallyvisibleeventhoughsomeinternalyolkmayhaveremained(Snyder2002).Therelationshipbetweenyolksacareaanddphwasusedtodescribeyolksacabsorptionrate.FincurlwasmeasuredonlarvaethatperformedintheUsprintswimchambertests.Fincurlwasquantifiedonascaleof0-4thatrepresentsthepercentageoftheoutsidemarginofthepectoralfinaffectedbyfincurl:0-nofincurl,1-<25%,2–25to50%,3–50to75%,4–75to100%outsidemarginaffected.Measurementsweremadeforbothfinsandaddedforameasureoftotalfincurl.
VELOCITY×TEMPERATURE
Theeffectsofvelocityandtemperatureonlarvaldevelopmentwereexaminedina3×2factorialexperiment.Averagevaluesofthethreevelocitytreatmentswere0,10,and21cm/s.Velocitytreatmentswerechosentoprovideacontroltreatment(0cm/s)andapproximatetherangeofvelocitiesfreeembryosmayexperienceintheUpperMissouriBasin(Braatenetal.,2008).Highervelocitiesthatmaybeexperiencedwereavoidedduetoexcessivecentripetalforcesandinabilitytomakeobservations.Averagevaluesofthetwotemperaturetreatments(nominally15and20°C)were15.3°C(SD=0.6)and21.0°C(SD=0.6).Temperaturetreatments
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werechosentoapproximatethepredictedrangeofoptimalspawningtemperaturesforpallidsturgeon(Kappenmanetal.,2013).
Experimentswereconductedineighteen0.61mdiametercirculartankswitha0.46mdepth.A0.32mdiameterPVCinsertwascenteredwithinthetankstocreatea0.15mwidecircularchannelintowhichembryoswereplaced.Tankswereprovidedwithflow-throughwaterataminimumrateof5.7L/min.Inthe0cm/streatments,waterenteredthetankapproximately4cmabovethewatersurfacefromaverticallyorientatedopeningwitha13.0mmdiameter.Waterenteredthe10cm/sand21cm/streatmenttanksfromnozzles(6.2and10.6mmdiameters,respectively)locatedalongtheoutsidewallandapproximately6cmbelowthewatersurfacetoprovideaclockwisecurrent.Nozzlesweredirectedattheoutsidewalltodispersethestrongjetofwaterandlimitdamagetoembryos.WatervelocitywasmeasuredwithaMarsh-McBirneyFlo-Mate2000currentmeter(HachCorp.,Loveland,CO,U.S.)at0.6×waterdepth(‘averagevelocity’ofthewatercolumn)and3cmabovethetankbottom(‘bottomvelocity’)inthemiddleofthechannelatfourequidistantlocations(TableI).Nominalvelocities(i.e.0,10,and21cm/s)refertotheaverageofthevelocitiesmeasuredat0.6×D.Velocitytreatmentswererandomlyassignedtotanks.
Afullsetofpilotstudieswereconductedwithfreeembryosfromthefirstspawningevent(25May2017)todeterminekeybehaviors,observationtechniques,samplingtechniquesandexperimentaldesign.Observationsfrompilotstudieswereusedtosupplementresults.Inpilotstudies,observationsoccurredat800and1600hrs.However,duetolimiteddifferencesbetweenobservationsweonlyconductedobservationsat800hrswithfishfromthesecondspawningevent(13June2017).Earlyhatchembryos(hatchedwithin12hoursofthefirstobservedhatch)fromthesecondspawningeventwererandomlyassignedingroupsof10toone‘observation’andtwo‘sampling’tanksforeachtreatment.Tenembryoswereassignedtoobservationtanksand300embryoswereassignedtosamplingtanks.Fiveembryos/larvaefromeachtreatmentweresampleddailyfromoneofthesamplingtanksandtotallength(mm),yolksacarea(mm2),presenceoffood,andpresenceofpigmentplugweremeasured.Tenembryos/larvaeweresampledfromtanksinwhichembryos/larvaewereseparatedintogroupsassociatedwiththebottomandwatercolumn,withfivefromeachgroupsampled.Observationtankswereobservedfor10-15mindailybetween10:00and13:00hrsandmortality,proportionindrift/onthebottom,swimmingbehavior,andhorizontal/verticalorientationwererecorded.Mechanicalvibrationscreatedbytappingthetankandadirectedjetofwaterfromapipettewereusedtotestthedevelopmentandevolutionofescaperesponsesinembryos/larvaeafterobservationswerecompleted.Mortalitiesintheobservationtankswerereplacedafterobservationswithembryos/larvaefromasamplingtankofthesametreatment.One-twominutesofunderwatervideo(HeroSession,GoPro,SanMateo,California,U.S.)and10minofoverheadvideo(HandicamHDR-XR-150,Sony,Tokyo,Japan)ofeach
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observationtankwererecordeddailyandreviewedtosupplementobservationnotes.Observationsandsamplingweretakenfrom1-30dph,dependentonsurvival.
ARTIFICIALRIVER
Freeembryo/larvalbehaviorwasobservedinalargeovalartificialriver(20mcircumference;Fig.3).TheartificialriverwasfabricatedbyHydroComposites,LLC(Stockdale,Texas,U.S.)andconsistedoftwostraightchannels(6.42mlongand1.56mwide),tworiverbends(5.81moutsidediameterand1.56mwide)andacenterwallseparatingthechannels.ChannelsarelabeledC1andC2andbendslabeledB1andB2forreference(Fig.4).Waterwassuppliedtotheriverviaare-usesystem,whichusedamixofon-sitecoldandwarmspringwater,andwasmaintainedat20.6°C(SD=0.6°C).Awoodenwingdike(0.05mlength×0.60mwidth×0.60mtall)wasplacedattheupstreamendofC2andasandbag(0.30mlength×0.72mwidth×0.15mtall)wasplaced3.4mdownstreamtocreateeddyhabitat(Fig.4).
Approximately0.06m3offoursubstratetypeswereplacedonthebottomofC1withthesizeofthesubstratesdecreasinginthedownstreamdirection:boulder(150-450mmoutsidediameter),cobble(18-45mm),gravel(5-15mm),andsand(0.3-5mm).TwoSulzerelectricmotors(Sulzer/ABSRW3022A17/6Mixers;SulzerInc.Switzerland)generatedvelocityandwereplaced0.8mabovethesubstrate,0.4mfromtheoutsidewall,and2.9mapartinC1.Therheostatpowersettingwassetat95%togeneratevelocities>2m/stodistributethesubstrate.
Waterdepthvariedfrom0.92–1.13mdependingonthepresenceandthicknessofsubstrate.Additionallargeboulderswereplacedatseverallocationsagainsttheinsidewalltocreateadditionaleddyhabitatsoverbareplasticandsandsubstrates(Fig.5).Therheostatpowersettingwasdecreasedto55%foraseriesofpilotstudiesconductedwithfreeembryosfromthefirstspawningevent(25May2017).However,theelectricmotorscausedhighmortalityandahighpitchanddecibelnoisethatmayhavedisruptednaturalbehavior.Subsequently,motorswerereplacedwithspraybarsthatspannedthewidthofthechannelandwerelocated0.5mabovethebottomand3mfromtheupstreamendofeachchannel.Afterfreeembryosfromthesecondspawningevent(13June2017)wereassignedtothevelocity×temperaturetreatments,allremainingunhatchedeggs(~5,000)wereplacedin/betweenboulder,cobble,gravel,andsandsubstrates.Approximately1000larvae(17dph)fromthefirstspawningevent(25May2017)wereplacedintheriveratthesametime.Alargemortalityeventoccurredon21June2017andtheriverwascleanedthenrestockedon22June2017with1000freeembryosfromthesecondspawningevent(5dph)and1000larvaefromthefirstspawningevent(22dph).Duetomortalityintheartificialriverandsubsequentreplacementwithlarvaefromholdingtanks,comparisonofgrowthratesamongrearingenvironmentswasnotpossible.
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Embryos/larvaewereobserveddaily,with10minofobservationateachofthe10observationwindows.Observationstechniqueswerethesameasforthevelocity×temperaturetreatments.Fivetofifteenminutesofunderwatervideo(HeroSession,GoPro,SanMateo,California,U.S.)andvideotakenfromoutsidetheobservationwindows(HandicamHDR-XR-150,Sony,Tokyo,Japan)wastakendailyandreviewedtosupplementobservationnotes.Observationsweretakenfrom0-71dph.Afterthecompletionofexperiments,bottomvelocities(3cmabovesubstrate)weremeasuredwithaMarsh-McBirneyFlo-Mate2000currentmeter(HachCorp.,Loveland,CO,U.S.)every10cmlongitudinallyand6cmlatitudinallyusinga30sfixedpointaverage(velocitiesvariedtemporallyatagivenlocation).Inriverbendsthecurrentmeterwasorientedparalleltothewallsofthetankatthepointofmeasurementandfacingtheupstreamdirection.Theriverwasnotmappedduringpilotstudiesbutpointmeasurementsofvelocitieswherelarvaewereobservedonthebottomwererecorded.
SWIMCHAMBER
Ucrittestswereconductedinasmallswimchamber(5L;30.0×7.5×7.5cmtestsection;LoligoSystems,Tjele,Denmark)toestimatemaximumaerobiccapacityandUsprinttestswereconductedinalargeswimchamber(185L;87.5×25.0×25.0cmtestsection)toestimatemaximumanaerobiccapacity(Brett,1964;Starrsetal.,2011).Swimchamberswereequippedwithamotorandvariablefrequencydriverthatallowedrapidandprecisevelocityadjustments.AMarsh-McBirneyFlo-Mate2000currentmeter(HachCorp.,Loveland,CO,U.S.)wasusedtocalibratevelocitysettingsbytaking30sfixedpointaveragedmeasurementsat0.6timesthewaterdepthforeachvelocitysetting.Flowstraightenerslocatedupstreamofthetestsectionprovidedrectilinearmicro-turbulentflowandanapproximatelyuniformvelocityprofile.Swimchambersweresuppliedwiththesameflowthroughwellwaterthatsuppliedtheholdingtanksandwatertemperaturedifferedlittle(±0.5°C;range)amongholdingtanksandswimchambers.Ucrittestsoccurredat21.1±1.4°CandUsprinttestsat19.8±1.1°C.LarvaefromthesecondspawningeventwereusedfortheUcrittestsandwereheldina1.8mcirculartanksat21.1±0.6°C.Ucrittestswereconducteddailybeginningon6dph.However,embryoswerenotabletocompletetheacclimationperiod(15minat5cm/s)until10dayspost.Subsequently,tenlarvaeweretestedeveryotherdayuntil32dph.LarvaefromthefirstspawningeventwereusedfortheUsprinttest(64-78dph)andwereheldina1.8mcirculartankandtheartificialriverat20.5°C(SD=0.6°C).
Testsbeganwitha15minacclimationperiodat5cm/sfollowedbya5cm/svelocityincreaseevery5minintheUcrittestandevery15sintheUsprinttest.Motorswereturnedoffwhenalarvaebecameimpinged,whichwasdefinedashavinggreaterthanathirdoftheirbodyrestingonthedownstreamgratefor3s.Aftera2minrest,thetestresumedatthevelocityincrementwhereimpingementoccurredintheUcrittestwhereasvelocitywasresetto
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10cm/sintheUsprinttests.Thelarvaewasconsideredfatiguedandthetestendedafterthethirdimpingement(Allenetal.,2006;Verhilleetal.,2014).UcritandUsprintvalueswerecalculatedusingtheformulaprovidedbyBrett(1964):
(1) Ucrit,Usprint=Ui+[U(ti×t-1)]whereUiisthepenultimatevelocity(cm/s),tiistheamountoftime(s)thefishswaminthefinalincrement,tisthetimeincrementbetweenvelocityincreases(300sand15s,respectively)andUisthewatervelocityincrement(5cm/s).Onlythehighestrecorded
Ucrit/Usprintvalueoutofthethreeattemptswereincludedinthedatasetusedforanalysis.
DATAANALYSIS
Multipleregressionwasusedtoexaminerelationshipsamongresponsevariables(length,yolksacarea,UcritandUsprint)andexplanatoryvariables(seeTableIIforlistofvariablesexamined).Interactionswereincludedinmodelsiftheywerehypothesizedtobebiologicallymeaningfuland/orpatternswereobservedinexploratorygraphs.Extra-sumofsquaresF-testswereusedtodeterminetheinclusion/exclusionofacovariatefromtheinferentialmodel(RamseyandSchafer,2002),withcovariateswiththeleaststatisticalsupportremovedfirst.Logisticregressionwasusedtoexaminerelationshipsamongthepresenceoffood,velocity,temperature,length,andage.Thesamemodelselectionprocessusedforlinearregressionwasusedforlogisticregressionwithlikelihoodratiotestsusedtoassessstatisticalevidence(RamseyandSchafer,2002).Lengthandageeffectswereexaminedinseparatemodelsduetothecorrelationofthesevariables.Age,cumulativethermalunits,andlengthattheonsetandconclusionofdevelopmenteventsarepresented(TableIII).
Anaturallogtransformation(ln)wasappliedtotheabsoluteUcrit(cm/s)valuesduetodatabeingseverelypositivelyskewed.RelativeUcrit/Usprintvalues(bodylengths/s)werecalculatedbydividingabsoluteUcrit/Usprintvalues(cm/s)byfishlength(cm).DifferencesinrelativeUsprintbetweentankswasexaminedwithaWelchtwosamplet-test(RamseyandSchafer,2002).
Observationaldatawasnotstatisticallyanalyzedduetoitssubjectivity,lackofnormality,lackoflinearity,andlackofreplication.Instead,thefirstobservationofnewbehaviors,dominantbehaviors,andshiftsinbehaviorsarereported.
Assumptionsofhomogeneityofvariance,normality,linearity,andmulticollinearityforregressionanalyseswereassessedusingplotsofresidualsversusfittedvalues,normalquantilequantileplots,plotsofresponsevariablesversuscontinuousexplanatoryvariables,andvarianceinflationfactors,respectively.Allassumptionswereadequatelymet.Regressionwas
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performedinprogramRversion3.2.3(RCoreTeam2015)usingthelmfunction.
RESULTS
VELOCITY×TEMPERATURE
EmergenceandDevelopmentalStages
Massemergenceoffreeembryosfromthe1stspawningeventoccurredat6dayspostfertilization(dpf;97CTU;incubatedat16.1°C).Massemergenceofembryosfromthesecondspawningeventoccurred7dpf(110CTU)foreggsincubatedat15.5°Cand4dpf(82CTU)foreggsincubatedat20.5°C.Embryoshatchedat15.5°Cwerelonger(8.2mm)thanatthosehatchedat20.5°C(7.9mm;t81=5.5,P<0.0001).Swimupbehaviorwasobservedimmediatelyafterhatch.
Presenceoffoodinstomachsat15°Cwasfirstobservedat18dph(275CTU)inthe0cm/sand11cm/streatmentsand19dph(291CTU)inthe20cm/streatment.Theproportionoflarvaewithfoodintheirstomachsgenerallyincreasedwithdphbutremainedlessthan0.6by30dph.At20°Cthepresenceoffoodwasfirstobservedat10dph(205CTU)andfoodwaspresentinallsampledlarvaeby13dph(268CTU).However,theproportionoflarvaewithfoodintheirstomachsdecreasedmarkedlyat19dph(398CTU)andsubsequentdays.Logisticregressionindicatedtherewasstrongevidencefortherelationshipbetweenageandpresenceoffoodtodependontemperature(χ2=83.2,df=1,P<0.0001;TableIV,Fig.6).Logisticregressionindicatedtherewasnoevidenceforarelationshipbetweenpresenceoffoodandvelocityinbothage(χ2=2.47,df=2,P=0.29)andlength(χ2=3.35,df=2,P=0.19)models.
Lengthwasamoreprecisepredictorofthepresenceoffood,withpresenceoffoodfirstobservedatanaveragevalueof18.8mmat15°Cand19.6mmat20°Candthesmallestindividualsobservedwithfoodpresentinthestomachwere18.3mmand18.4mmat15and20°C,respectively(TableIII).Therewasstrongevidencefortherelationshipbetweenlengthandpresenceoffoodtodependontemperature(χ2=17.97,df=1,P<0.0001;Fig.7).Foodwasnotpresentinanylarvaethathadnotexpelledtheirmelaninplugorthathadexternallyvisibleyolksac.Subsequently,sturgeonareclassifiedasfreeembryosbefore18and10dphinthe15and20°Ctreatments,respectively,andlarvaethereafter.
Length
Aquadraticrelationshipbetweenlength(mm)anddaysposthatch(dph)wasobservedwiththerateofgrowthbeinggreatestdirectlyafterhatch,graduallydecreasing,andeventuallybecomingnegativeat22(337CTU)and13dph(268CTU)inthe15and20°Ctreatments,
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respectively(Fig.8).Thenegativegrowthratesmayhaveresultedfromlarvaenotfeedingefficientlyontheprovidedfood.Thus,onlygrowththatwassustainedbyyolksacutilizationwasmodeledinregressionanalysis.Theexpulsionofthemelaninplugwasusedtoindicateyolksacutilizationwascomplete.Melaninplugswerefirstobservedbeingshedat15(230CTU)and8dph(163CTU)inthe15and20°Ctreatments,respectively(TableIII).Thesheddingofthemelaninplugdidnotdifferamongvelocitytreatments.Allmelaninplugsinsampledlarvaewereshedby18(275CTU)and10dph(205CTU)at15and20°C,respectively(TableIII).Thus,areduceddatasetfromemergenceto18and10dphforthe15and20°Ctreatments,respectively,wasusedforlengthanalysis.
Therewasstrongevidenceforanassociationbetweengrowthrateandtemperature(i.e.temperature×ageinteraction;F2,609=311.3,P<0.0001),withthegrowthratebeingsignificantlygreaterat20than15°C(Fig.8).Therewasnoevidencethatgrowthrate(F2,606=1.1;P=0.32)orlength(F2,606=2.6;P=0.11)wasassociatedwithvelocity.
YolkSacArea
Absenceofexternallyvisibleyolksacswerefirstobservedat15(230CTU)and9dph(184CTU)inthe15and20°Ctreatmentsandallsampledspecimenslackedyolksacsby17(260CTU)and10dph(205CTU),respectively.Analysiswasperformedonareduceddatasetforfreeembryosfromemergencetowhenallsampledspecimenslackedexternallyvisibleyolksacs.Anapproximatelylinearrelationshipwasobservedbetweenyolksacareaandage(dph).Therewasnoevidenceforarelationshipbetweenvelocityandyolksacarea(F2,508=2.4,P=0.09).Yolksacareaandtherateofdepletionwasrelatedtotemperature(F2,510=369.7,P<0.0001).Therateofyolksacdepletionwas0.29mm2/dphgreaterat20°C(0.71mm2/dph,95%CI=0.65,0.76)thanat15°C(0.42mm2/dph,95%CI=0.41,0.44;Fig.9).
Anapproximatelylinearrelationshipwasobservedbetweenyolksacareaandlength.Therewasnoevidenceforarelationshipbetweenvelocityandyolksacarea(F2,508=0.5,P=0.64).Therewasstrongevidencefortherateofyolksacdepletion,relativetolength,todependontemperature(F1,508=45.6,P<0.0001).Yolksacutilizationresultedinagreaterincreaseinlengthat20°Cthanat15°C(Fig.10):a1.00mm2reductioninyolksacarearesultedina1.42mmincreaseinlength(95%CI=1.36,1.49)at15°Ccomparedtoa1.89mmincreaseinlength(95%CI=1.64,2.24)at20°C.
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Behavior
Individualfreeembryo/larvalbehaviorandbehavioramongindividualswashighlyvariable.Thus,resultsfocusonwhenbehaviorwasfirstobserved,behaviordisplayedbythemajorityoffreeembryos/larvae,andnotabletemporalshiftsinbehaviors.Swimupbehaviorwastheonlyswimmingtypeobservedimmediatelyafterhatchuntil10dphinthe15°Ctanksand5dphinthe20°Ctanks.Generally,contactwiththebottomorsidesofthetanksinitiatedverticalswimupbehaviorandcontactwiththewatersurfaceresultedindriftdownbehavior.Thefrequencyofswimupbehavior(i.e.timebetweenconsecutiveswimupbehaviors)wasnotablyhigherinthe20°Ctanksthanthe15°Ctanksandhigherinthe10cm/sand21cm/stanksthanthe0cm/stanks.Thehigherfrequencyofswimupbehaviorinthe10cm/sand21cm/stanksat20°Cresultedinthemajorityoftheembryosbeinglocatedatthesurfacecomparedtoembryosbeingdistributedthroughoutthecolumnintheothertreatments.Orientationoftheswimupbehaviorbecamelessverticalandmorehorizontalastheembryosdevelopedandconcurrentlythespeedofverticalmigrationslowed.Themajorityofembryosdevelopedhorizontalorientationby11dphin15°Ctanksand5dphin20°C.Horizontalorientationwaspredominantlypositiveforembryos/larvaeorientedonthebottomwhereasembryos/larvaeinthewatercolumnwerealmostequallypositivelyandnegativelyorientedfortheremainderoftheexperiment.
Embryoswerefirstobservedorientatingonthebottom11dphat15°Cand6dphat20°Cinallvelocitytreatments.Thiswasassociatedwithatransitionfromswimup-driftbehaviortosteadysustainedswimming.Theproportionofembryos/larvaeonthebottominthe10cm/s×20°Cand21cm/s×20°Ctreatmentsrosetopeaksof0.9and0.5by9dph,respectively,thenfluctuatedbetweenthepeakand0.0fortheremainderoftheexperiment.Consistenttrendsintheproportionofembryos/larvaeonthebottomwerehardtodiscernintheothertreatmentsandtheproportionfluctuateddrasticallyonadailybasis,butwasgenerallylessthan0.5.Differencesinyolksacarea,length,presenceoffood,andtheexpulsionofthemelaninplugwerenotobservedamongembryos/larvaesampledonthebottomversusthosesampledinthewatercolumn.Embryosorientedonthebottomwerefirstobservedholdingpositionagainstthecurrentinthe10cm/streatmentsat11dphinthe15°Ctanksand6dphinthe20°Ctanks.Embryoswereabletoholdpositionforbriefperiodsoftimeonthebottominthe21cm/streatmentsat12dphat15°Cand7dphat20°Cusingareasoflowvelocityneartheinsidewall.Whenwatervelocityonthebottomexceededswimmingabilitiesandresultedindownstreammovement,larvaewouldswimupintothewatercolumnandgobackintodrift.Larvaewerenotobservedmakingupstreamprogresswhileinthewatercolumnandtailbeatfrequencywasgenerallylowerforlarvaeinthewatercolumnvs.thoseattemptingtoholdpositiononthebottom.
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Startletotouchassociatedwithsamplingwasobserved1dphatbothtemperatures.Embryosdisplayeda‘C-type’startleresponse(arapidmovementofthebodyintotheshapeofa‘C’’;Blaxter&Batty,1985;Hardy&Litvak2004)followedbyaburstofswimmingthatlastslongerthanbehaviornotassociatedwithadisturbance.A‘C-type’startletomechanicalvibrationwasfirstobserved9-11dphat15°Cand4dphat20°C.Consistentstartleresponsestoajetofwaterwereobservedat10-11dphat15°Cand3-5daysat20°C;arelationshipbetweenvelocityandastartleresponsewasnotobserved.Themostprevalentresponsetothejetofwaterwastoorientpositivelytoitandswimagainstit,althoughfishoccasionallyswamawayfromthejet.Fishonthebottompressedtheirbodiesagainstthebottomandquicklyswambacktothebottomifthejetdisplacedthem.Priortoastartleresponsedeveloping,thejetofwaterwouldresultinfishceasingswimmingactivityandgoingintopassivedriftforashortperiodoftime.Thisresponsewasoccasionallyobservedafterastartleresponsedevelopedandwasmostprevalentinthe10and21cm/streatments.
Mortality
Mortalitywaslow(≤10%)in20°Cobservationtanksup16dph,atwhichpointmortalityroseexponentiallyresultingin100%mortalityby21dphinbothobservationandsamplingtanks(Fig.11).Mortalityinthe0cm/s×15°Cand10cm/s×15°Ctanksfirstoccurred4daysafteremergenceanddailymortalityrateaveraged20%and7%,respectively,between4-18dph.Mortalityratewaslow(≤10%)19-27dphbeforerisingto50%and30%by30dphinthe0cm/s×15°Cand10cm/s×15°Ctanks(Fig.11).Mortalityrateinthe21cm/s×15°Ctankwaslow(≤10%)fromemergenceto29dphbutroseto50%on30dph.
ARTIFICIALRIVER
Complexflowconditionsanddiversesubstratetypeswerecreatedintheartificialriverthatapproximatedmanyhabitattypespresentinthenativewatersofpallidsturgeon.Largersubstrates(boulder,cobble,andgravel)wereconfinedtoC1andB1whilesandwasdistributedtolocationsthroughouttheriver(Fig.5).Bareplasticwasthemostprevalentsubstrate(73.7%;32.4m2)followedbysand(9.6%;4.2m2),cobble(8.6%;3.8m2),gravel(5.0%;2.2m2),boulder(3.4%;1.5m2),andamixtureofgravelandsand(0.7%;0.32m2).ThelargestdepositsofsandsoccurredatthedownstreamendofC1andformedintosmallsanddunes(maximumheight15cm).Finesandofatancolorcollectedalmostexclusivelydownstreamofthesandbag(Fig.4-5,coarsersandwasadarkgrey).Averagebottomvelocitywas6.4cm/s(SD=6.2)andrangedfrom-12.2cm/sto24.4cm/s.Areasofhighvelocityexistedattheupstreamendsofeachchannelandlowvelocityareasexistedattheupstreamendofeachriverbendalongtheoutsideedge(Fig.12).Thewingdikecreatedaneddywitha1.43m2bottomfootprintandmultiplesmallereddieswerecreatedbehindtheboulders,sandbag,alongtheinsidewall.
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Freeembryosswamupimmediatelyafterhatchregardlessofthesubstratetheyhatchedin.Someembryoswereobservedgettingstuckintheinterstitialspacesamongthecobbledirectlyafterhatchforthedurationoftheobservationperiod(10min).However,thisappearedtobearesultofadifficultyadjustingorientationandgettingoutofthetightinterstitialspaces.Swimupbehaviorwasobservedexclusivelyuntil5dph.Contactwiththebottomorsidesofthetankusuallyinitiatedswimupbehaviorandcontactwiththewatersurfacegenerallystimulateddriftdownbehavior.Embryoswerepredominantlyinthelowerhalfofthewatercolumn0-1dph(≤.5m)butweredistributedthroughouttheentirewatercolumnthereafter.After5dphorientationbegantobecomemorehorizontalandasteadysustainedswimmingpatternwasobserved.
Embryoswerefirstobservedonthebottomon7dphandtheproportionofembryos/larvaeonthebottomreachedapeakofapproximately0.9on10dphandsubsequentlyfluctuatedbetween0.4and0.9.Fishwereobservedinthewatercolumnthroughoutthedurationoftheexperiment.Embryos/larvaepredominantlysettledontheplasticsubstrateinC2andB2(Fig.4).From7-10dphembryoswereoftenobservedonthesandinfrontofandbehindthewingdikeandthesandandgravelattheupstreamedgeofthebouldersinC1butwererarelyobservedintheseareasafter10dph(Fig.4-5).Duringthistime(7-10dph)oneofthelargestcongregationofembryos(100-200)wasobservedintheeddylinedownstreamofwingdike.Embryosremainedonthebottominthisareadespiteitbeingturbulentandflowdirectionchangingfrequentlyanddrastically.
After10dphlarvaewereassociatedalmostexclusivelywithplasticsubstrateinC2andB2withtheexceptionofthesandbelowthesandbagandthesurfacesofthebouldersinC1(Fig.4-5).Embryos/larvaewereneverobservedsettlingonthecobbleinC1andrarelysettledonthelargeareaofsandbelowthecobbleonthedownstreamendofC1(Fig.5).Touchingthecobblesubstrateorswimmingclosetoitgenerallyresultedinembryos/larvaeswimminghigherinthewatercolumn.
Embryos/larvaegenerallyselectedareaswithvelocitiesrangingfrom-5–15cm/s.Eddyhabitatwasnotpreferentiallyselectedoverhabitatinthemaincurrent.Areasofhighvelocity(>20cm/s)wereavoidedbyembryos/larvaethroughoutthedurationoftheexperiment.Larvaeinthecurrentswamvigorouslytoholdpositiononthebottom,butwhenwatervelocityexceededswimmingabilitiestheygenerallyswamupintothewatercolumnandswimmingintensitydecreased.Larvaewereneverobservedmakingsustainedupstreamprogresswhileinthewatercolumnoronthebottom.Loosecongregationsofembryos/larvaewereobservedbutcontactwitheachothergenerallyinitiatedasmallstartleresponse.Contactofsmallerfishfromthesecondspawningeventwithlargerfishfromthefirstspawningeventgenerallystimulatedswimupbehaviorforthesmallerindividual.Foodavailabilityappearedtohavea
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strongeffectonlarvalswimmingbehavior.Foodwasexperimentallywithheldfor1.5dayson7/30(61dphlarvaefromfirstspawningeventand44dphlarvaefromsecondspawningevent)andresultedin>90%offishindownstreamdriftinthewatercolumn.Whenalargeamountofnegativelybuoyantfoodwasadded,>90%offishsettledtothebottomwithin5min.
SWIMCHAMBER
Atotalof117Ucrittestsand75Usprinttestsweresuccessfullycompleted.Larvalpallidsturgeonshowedhighmotivationtoswimintheswimchamber,withonlyasinglelarvaeinanUcrittestnotswimmingduringtheacclimationperiod(removedfromdataset)andalllarvaeinUsprinttestcompletingtheacclimationperiod.Larvaedidnotshowapreferenceforswimmingonthebottom,rarelystationheldonthebottom,andwereobservedswimmingthroughouttheswimchamber.Mostfishperformedbestontheir1stattempt:44%/56%achievedtheirhighestUcrit/Usprintvalueonthefirstattempt,26%/29%onthesecond,and30%/15%onthethird.
RegressionanalysisprovidedevidenceforrelationshipsbetweenUcrit,ageandlengthandbetweenUsprint,length,andholdingenvironment(TableIV,Fig.13-15).InbothUcritandUsprinttests,lengthhadthelargesteffectonswimmingabilities(TableIV).AbsoluteUcrit(cm/s)waspositivelyrelatedtolength(P<0.0001)andage(P<0.0001;Fig.13)whereasrelativeUcrit(bodylengths/s)wasnegativelyrelatedtolength(P<0.0001)andage(P<0.0001;Fig.14).Ageandlengthwerehighlycorrelated(0.86)amongtheyoungerfishintheUcrittestsbutcorrelationdecreased(0.24)amongtheolderfishtestedintheUsprinttestsandtherewasnoevidenceforarelationshipbetweenageandabsoluteUsprint(P=0.18)orrelativeUsprint(P=0.58).TherewasevidenceforholdingenvironmentbeingassociatedwithabsoluteUsprintinboththeage(P=0.02)andlength(P=0.007)models,withUsprintvaluesbeinganaverageof5.3cm/s(95%CI:1.2,7.5)greaterforfishraisedintheartificialriverthanina1.8mcirculartankafteraccountingforageand4.4cm/s(95%CI:1.0,9.7)afteraccountingforlength(Fig.15).Similarly,therewasstrongevidenceforarelationshipbetweenrelativeUsprintandholdingenvironment(P=0.007),withthemeanUsprintoffishfromtheartificialriver(4.9BL/s)being0.5BL/s(95%CI:0.1,0.8)greaterthanthemeanUsprintoffishfromthe1.8mcirculartanks(4.5BL/s).TherewasnoevidenceforarelationshipbetweenfincurlandUsprintinanyofthemodels(P>.15,TableIV).
DISCUSSION
Integratinginformationonpallidsturgeonlarvalbehavior,swimmingabilitiesandhabitatselectionwithenvironmentalvariablessuchastemperature,substrate,andvelocitywillallowustore-evaluatethelarvaldrifthypothesisandbetterunderstandtheearlylifehistoryrecruitmentbottleneck.Inthisstudy,wesawevidencethatlarvaldriftmaycontinueafter
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exogenousfeedingbegins,resultinginlongerdriftdistances.Temperaturehadastrongeffectontherateofdevelopmentandresultswerecongruentwithpreviousstudies(Kynardetal.,2002,2007,Webbetal.,2007).Testsandobservationsofswimmingabilitiesindicatethatlarvalpallidsturgeonarerelativelyweakswimmersanddriftislikelycurrentdominatedearlyindevelopmentandtheabilitytomoveupstreamisseverelylimited.Duetologisticrestraintsandthecomplexityofaccuratelyaccountingfordriftpathwaysandvelocities,driftspeedswerenotquantitativelymeasured.However,importantexperimentalprotocolsweredevelopedthatwillfacilitateandenhancefuturestudiesattheBozemanFishTechnologyCenter.Additionally,aphotographicguidetolarvaldevelopmentwasdevelopedthatwillfacilitatethedeterminationoflarvalageinthefieldandhelpstandardizelengthandyolksacmeasurements.Althoughresultsaddtoourunderstandingoflarvaldriftanddevelopment,theycallintoquestionpartsofthelarvaldrifthypothesisanddemonstratethatfurtherresearchisneededtounderstandtherecruitmentbottleneck.
Pallidsturgeonarebelievedtospawnovercoarsesubstrates(boulder,cobble,gravel)andadhesiveeggsattachtothesubstrate(Dettlaffetal.,1993;U.S.GeologicalSurvey,2007;DeLonayetal.,2009,2014,2016).Timetohatchwashighlycorrelatedtotemperatureandmasshatchwasobservedbetween3-7daysafterfertilization,whichagreeswithobservationsofpreviousstudies(DeLonayetal.,2016).Atlanticsturgeon(Acipenseroxyrinchus),shortnosesturgeon(A.brevirostrum)andwhitesturgeon(A.transmontanus)allseekcovershortlyafterhatchwhenappropriatesubstratesareprovidedbutareobserveddisplayingdriftbehaviorwhensubstrateswerenotprovided(RichmondandKynard,1995;KynardandHorgan,2002;Kynardetal.,2002;McAdam,2011).However,observationsofembryoshatchingoutofvarioussubstrates(sand,gravel,cobble,andboulder)confirmsreportsofswimupbehavioroccurringdirectlyafterhatchforpallidsturgeon(Kynardetal.,2002,2007).
Weobservedembryosdriftinginthelowerhalfofthewatercolumn(<0.5m)from0-1dph;thereafter,embryos/larvaewereobserveddriftingthroughoutthewatercolumn.Kynardetal.(2002,2007)observedembryosnearthebottomfrom0-5dph,intheupperwatercolumnfrom~6-9dph,andnearoronthebottomthereafter.However,theseexperimentswereconductedinalowvelocityenvironment(2cm/s)withinasmalltestingapparatus(300cmdepthx15cmdiameter).Giventhatcontactwithsurfacesgenerallyelicitaswimupresponse,thesmalldiametertesttubemayhaveresultedinartificialresults.Thisislikelythecaseinalllaboratorystudies,wheretherelativesurfaceareaoftanksinrelationtowatervolumegreatlyexceedstheratioofbottomsurfaceareatowatervolumeinnaturalenvironments.Fieldstudiesandcollections(BraatenandFuller,2002,2003,2004,2005;Braatenetal.,2008,2012a)indicatethatembryosprimarilydriftclosetothebottom.Inthedeeper,swifter,andmorehydraulicallycomplexenvironmentsoftheMissouriandMississippiRivers,itmaybeharderforembryostomoveupinthewatercolumnandtheirlocationmaybe
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primarilydeterminedbythecurrent(Braatenetal.,2008).Additionally,giventhatfreeembryosarenegativelybuoyant,swimupwhentheycontactasurface,arerelativelyweakswimmersearlyindevelopment,andeventuallysettleonthebottom,itisreasonabletohypothesizethatmostembryosaretransportedindriftnearthebottom.Locationinthewatercolumnhasalargeeffectondriftdistance,asvelocitymappingintheMissouriRiverbelowFortPeck,Montana,hasshowndriftnearthebottomcanbetwiceasslowasdriftinthewatercolumn(MarotzandLorang,2017).
Embryonicswimmingabilitieswereveryweakanddriftatthisstageislikelycurrentdominated.Braatenetal.(2008)suggestsdriftspeedsaresimilartocurrent,asthishasbeenobservedinothersturgeonspecies:Beluga(Husohuso),Russian(Acipensergueldenstaedti)andstellatesturgeon(A.stellatus)driftatabout80-90%oftherivervelocity(Khoderevskaya,2002,citedbyGisbertandRuban,2003).Theobservedburstup–driftdowncyclicbehaviormayhaveevolvedtokeepembryosfromgettingstuckininterstitialspacesinthesubstrate,facilitateexitingeddyhabitat,andenhanceentrainmentinthemaincurrent.Swimupbehaviorinsmalleddiesbehindbouldersandthesandbagintheartificialriverquicklyremovedembryosfromtheseretentionareasandbackintothecurrent.Additionally,embryoswereoftenobservedceasingswimmingactivityafterexperiencinganabruptincreaseinwatervelocity,whichmaybeanadaptiontofacilitateentrainmentinthemaincurrent.However,manyembryoscaughtinthelargeeddybelowthewingdikespentconsiderabletimethereandtheirabilitytoreduceretentiontimeinlargerbackwaterareasremainsunclear.Fieldstudiesindicatelarvaedriftforlongdistances(245-530km)andmeasureddriftratesindicatelarvaedriftatratesslightlyslowerthanthemaincurrent(66-70cm/sversus72cm/smeanwatervelocity;Brattenetal.,2008,2012a).However,givenlimitationsonthevolumeandlocationofwatersampled,itislikelytheseresultspertaintothefastestdriftingindividuals(MarotzandLorang,2017).Duetolowrecapturerates,thefateofthevastmajorityoflarvaeisunknown(Braatenetal.,2008,2012a).However,recaptureofjuvenilesfromthesestudiesindicatethatsomeareabletodevelopbeforeendingupinreservoirs(Braatenetal.,2012b).
Velocitymappingof338kmoftheMissouriRiverdownstreamofFortPeck,Montana,andsimulateddriftpathwaysindicatethatmostdriftingparticlesinthethalwegwouldbedispersedintolowvelocityretentionareas(i.e.backwaters,low-velocityrivermargins,andsidechannels)inlessthan3.1km(MarotzandLorang,2017).Wedidnotobservebehaviorthatwouldallowembryostoquicklyexitlargebackwaterorlowvelocityareasfarfromthemaincurrentandlarvaldriftwouldbesubstantiallyslowedbyenteringtheseareas.Flowmodelinganddriftsimulationsneedtobefurtherassessedwithempiricalobservationsofdriftingparticlesandembryos/larvaeinordertounderstandhowearlylifeswimmingbehavioraffectsdriftdistancesandverifypredicteddriftdistances.
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Presenceoffood,whichsignifiesthetransitionfromfreeembryostolarvae,firstoccurredat275CTU(18dph)and205CTU(10dph)at15and20°C,respectively.Whilethetransitionat20°Ccloselymatchesthe200CTUthresholddescribedbyKynardetal.(2007),thepresenceoffoodwasnoticedmuchlaterat15°C.Becauseweobservedlarvaeat15°Chavingdifficultyfeeding,itispossiblethatwemisidentifiedthistransition.However,observationsoftheabsenceoftheyolksacandmelaninplug,whichwerealwaysobservedbeforefoodwasobserved,didnotoccuruntil230CTU.Thisindicatesdevelopment,relativetoCTU,occurredataslowerrateat15°Cthanatwarmertemperatures(KynardandParker,2005;Kynardetal.,2002,2007),whichisconsistentwiththeloweryolksacutilizationefficiencyweobservedat15°Ccomparedto20°CintheVelocityxTemperatureexperiments.Theseobservationsarelikelyduetotheeffectsoftemperatureonenzymeactivity,metabolicrate,growth,anddevelopmentanddeserveacloserphysiologicalexamination(Fry,1971).Congruentwithresultsfrompreviousstudies,lengthwasthemostconsistentpredictoroflarvaldevelopment,withfoodpresentinlarvae18-20mminlength,regardlessoftemperatureofage(Snyder,2002;Kynardetal.2002,2007;Braatenetal.,2002,2008).Thesefindingsshowartificiallylowhypolimneticreleaseswilldelaydevelop,increasedriftdistances,andultimatelydecreaseembryosurvival.
Embryoswerefirstobservedsettlingonthebottomat11dph(168CTU)at15°Cand67dphat20°C(122-142CTU).Theseobservationscloselyprecededtheexpulsionofthemelaninplugandtheinitiationofexogenousfeeding.Duetodailyfluctuationsinsettlingbehaviorandaninabilitytodiscernwhenmostembryoshaddevelopedsettlingbehavior,werecommendusingtheagewhentheyolksacwasabsorbedinalllarvae(17and10dphat15and20°C,respectively)asaconservativeproxyofthedurationofdevelopmentneededtodevelopsettlingbehavior.This‘driftduration’closelymatchespreviouslyreportedranges(Kynardetal.,2007;Braatenetal.,2008,DeLonayetal.,2016).Theabsorptionoftheyolksacwasaccompaniedbychangesinbodyshapethatfacilitatedswimmingonthebottom(i.e.aflatventralsurfaceandmorefusiformshape).Comparisonoflength,yolksacarea,andpresence/absenceoffoodandthemelaninplugbetweenembryos/larvaesampledonthebottomandinthewatercolumndidnotrevealanydifferences,indicatingthatembryos/larvaewerelikelycyclingbetweensettlingonthebottomanddriftingbehavior.
Weobserveddriftinsomeportionofoursampleuntil30dphintheVelocityxTemperaturetreatmentand71dphintheartificialriver(i.e.theendofobservations).Kynardetal.(2007)suggestthatlarvaedon’tmigratedownstreamaftertheysettletothebottomafter~200CTUofdevelopment,basedonbehaviorofothersturgeonspecies(Kynardetal.,2002;KynardandHorgan,2002;Zhuangetal.,2002;KynardandParker,2005).Theyalsonotethattheyobservedyearlingjuvenilesdispersedownstream(B.Kynard,E.Parker,D.PughandT.Parker,unpubl.data)andthatitisunlikelythatyoungerfishwouldalsobedispersing.
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However,larvaldriftstudiesintheUpperMissouriRiverindicatethatsomeexogenouslyfeedinglarvaeremainindrift.ResultsfromBraatenetal.(2012a)showsimilardriftspeedsinthemainstemUpperMissouriamongcollectedlarvaeaged5-15dph,althoughcollectionofolderindividualsbecamerarerasdriftdistanceincreased(19.6°C).Similarly,Braatenetal.(2008)observedoverlapindriftspeedsof1-17dphembryos/larvaeinanaturalside-channeloftheUpperMissouri(17.8–24.5°C).Thetimepostreleasethatlarvaewerecollectedwasmostvariablefor17dphlarvaeanddriftspeedslowest(0.20m/sslowerthanthemeanwatercolumnvelocity).Theseresultscouldbeexplainedbylarvaecyclingfromsettlingonthebottomandswimmingupintodrift,whichwasobservedinourlaboratorysetting.
Steffensonetal.(2018)reportsdownstreamdispersalfromstockinglocationsforage-0(mean:153dph,range:64-202)toage-6hatcheryrearedpallidsturgeonintheLowerMissouri.TheLowerMissouriisdefinedasthe1305kmofundammedriverbelowGavinsPointDam,SouthDakota,totheconfluencewiththeMississippi.Thissegmenthasbeenhighlychannelizedfornavigationandmuchofthenaturallowvelocityandshallowdepthhabitathasbeeneliminated(Galatetal.,2000;ErwinandJacobson,2015).Generally,age0-6fishwererecapturedwithin30riverkilometers(rkm)downstreamfromstockinglocationsbutmuchlongerdistancesovera1,000rkmdownstreamwerealsoobserved(Steffensenetal.,2018).DownstreammovementofstockedjuvenileshasalsobeenobservedintheYellowstoneRiver(Jaegeretal.,2007),PlatteRiver(Snooketal.,2002),LowerMissouriRiver(Wilsonetal.,2008)andtheUpperMissouriandMariasRivers(Oldenburgetal.,2011).However,upstreammovementhasalsobeenobservedamongage-1andolderstockedfish(Jordanetal.,2006,Klumbetal.2012).Furtherresearchisneedtoidentifymovementpatternsofyoungpallidsturgeon,especiallydirectlyafterinitialsettling.Ourobservationsindicatemovementispredominantlydownstream0-71dphandtherateofdownstreammovementislikelyassociatedwithhabitatavailability.
Verylittleisknownaboutpallidsturgeonhabitatduetothecomplexityofstudyingspeciesinlargeturbidrivers,therarityofthespecies,andverylimitedanecdotaldataonhabitatuseinnaturalsystemsbeforedamsalteredavailablehabitat(Jordanetal.,2016).Adultandjuvenilesturgeonareoftenassociatedwithsandysubstratesindeepswiftwaterinthemainchannel(BramblettandWhite,2001;Jordanetal.,2006,Gerrityetal.,2008).YoungoftheyearpallidandshovelnosesturgeonintheMiddleMississippiRiver(320riverkilometersofchannelizedriverbetweentheconfluencesoftheOhioandMissouriRivers)werefoundtobeassociatedwithsandsubstratesinlowvelocity(~10cm/s)channelborderareas(Phelpsetal.2010).Sandwasthesecondmostcommonlyselectedsubstrateintheartificialriveraftertheplastictankbottom.Wehypothesizethatplasticwasselectedduetoitsgreaterrelativeavailabilityandfeedingefficiencybeinggreatestonthisflatsmoothsurface.Notably,weobservednolarvaesettlingonthecobblesubstrate.Near-boundaryturbulenceassociatedwith
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cobblemayhaveaffectedfishorientationandstabilityanddeterredlarvaefromsettlingintheseareas(TriticoandCotel,2010;Silvaetal.,2012).
SimilartoPhelpsetal.(2010),weobservedlarvaesettlinginlowvelocityareas(<15cm/s)andavoidingorswimmingupintodriftwhenvelocitiesexceededthisthreshold.SelectedhabitatappearedtobecloselyassociatedwithestimatesofmaximumsustainedswimmingvelocitiesfromUcrittests.Ifthisassociationholdsforolderfish,Ucrittestscouldbeausefultooltopredictwhenpallidsturgeontransitionfromlow-velocitychannelborderhabitatintothemainchannel.Adamsetal.(2003)reportsmeanUcritvaluesof36cm/sforpallidsturgeon180dph,indicatingaslowincreaseinswimmingabilitieswithage/length(meanlength:21.4cm).SimilarUcritvalueshavebeenreportedforothersturgeonspeciesandindicatethatsturgeonarerelativelyweakswimmerscomparedtootherfamiliesoffish(KatopodisandGervais,2011;Verhilleetal.,2014).Adamsetal.(2009)reportssimilarsprintingabilities,relativetosize,foryoungoftheyearpallidsturgeonranginginsizefrom13.0-16.9cm(40-70cm/s)and17.0-20.5cm(55-70cm/s).Thesevelocitiesrepresentsprintingvelocitiesthataresustainableforbriefperiods(≤15s;Brett,1964).Upstreammovementwouldbelimitedatthesevelocitiesandwepredictencounteringthesevelocitieswouldstimulatelarvaetogobackintodrift.
Interandintraspecificcompetitionforhabitatandfoodmayeffectdriftbehavior.Swimupbehaviorwasoftenobservedamonglarvaefromthefirstspawningeventwhentheycontactedlargerindividualsfromthesecondspawningevent(18daydifferenceinage)anddensecongregationsoflarvaewereneverobservedintheartificialriver.Availabilityoffoodappearedtobeastrongdeterminantoflarvalhabitatselection,withlarvaemostlysettlingonthebottominthechannelandbend(C2,B2)belowthepointoffoodentrydespitesimilarhabitat(i.e.similarvelocityandsubstrate)beingavailableintheotherchannelandbend(C1,B1).Relativelyhighdensitiesoflarvaeandcompetitionforfoodandhabitatmayhavecontributedtotheextendeddriftweobservedintheartificialriver.However,extendeddriftbehaviorwasalsoobservedintherelativelylowdensityobservationtanks(Velocity×Temperature;10fish/tank)andintheartificialriverattheendofobservationswhenlessthan50larvaewerepresent(dailysampling,mortality,andremovalforswimstudiesdecreasedfishdensities).Giventheobservedinfluenceoffoodavailabilityonhabitatselection,laboratorystudiesthatusenaturalpreyitems,suchasmidge(Chironomidae)andmayfly(Ephemeroptera)larvae,mayprovidemorerealisticinferencesonhabitatselection(Braatenetal.,2012b;Sechleretal.,2012).
Theabilityoflarvaetosurvivethetransitionfromendogenoustoexogenousfeedingislikelydependentontheavailabilityofsuitablehabitatandsufficientfoodsources.Earlylifestagesareparticularlysensitivetofooddeprivationandmortalityassociatedwithfooddeprivationoflarvalpallidsturgeonrearedat17°Cwasfirstobservedat17dphandwas97%
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by23dph(Kappenmanetal.,2011).Weobservedasimilartrendinthe20°CVelocity×Temperaturetanks,indicatinglarvaemayhavediedfromfeedinginefficiently.Shallowwaterandfloodplainhabitatsgenerallysupporthigherdensitiesofzooplanktonandbenthicinvertebratesandwerelikelyhistoricallyimportantnurseryareasforlarvalpallidsturgeon(Thorp,1992;ThorpandDelong,1994;WardandStanford,1995;Scheimeretal.,2001).However,damsandchannelizationhavedisconnectedtheMissouriRiverfromitsfloodplainandresultedinasubstantiallossofshallowwaterhabitat(HesseandSheets,1993;Gallatetal.,1996;Bowenetal.,2003).Thesedecreasesinsuitablehabitatlikelyresultinanextendeddriftphase,delaysinexogenousfeeding,increasedcompetitioninareaswithsuitablehabitat,andultimatelyincreasedmortality.Wilsonetal.(2008)andHaddixetal.(2009a,b)reportincreasedconcentrationsofstockedpallidsturgeondownstreamofstockinglocationsintheUpperMissouriRiver.Thepotentialeffectsofanextendeddownstreamdriftandsubsequentelevatedcompetitionindownstreamstretchesofmanagementareasshouldbeaconsiderationinstockingprotocols.DecreasinggrowthratesamongstockedpallidsturgeonintheLowerMissouriRivermaybeanindicationofelevatedinterspecificcompetitionwiththelargepopulationofshovelnosesturgeonandintraspecificcompetitionwithhatcheryrearedpallidsturgeon(Popeetal.,2010;Steffensenetal.,2018).
Resultsandobservationsfromourstudyindicatethatdownstreamdriftmaycontinueafterexogenousfeedingbeginsifsuitablehabitatisnotavailable.Theextentofdownstreamdriftislikelyhighestinchannelizedsegments,segmentswithlowhabitatdiversity,orareaswithhighlevelsofintraandinterspecificcompetition.Embryonicswimmingbehaviorsallowedembryostoexitsmallretentionareasandenterthemaincurrent,butareunlikelytosignificantlyreduceretentiontimesinlargeretentionareas.Weobservedtheswitchtoexogenousfeedingoccurringinalmosthalfthetimeat20°Cthanat15°C.Dammanagementpracticesthatincreasethetemperatureofreleasedwaterwillsignificantlydecreaselarvaldriftdistancesandlikelyincreaselarvalsurvival.Wedidnotobserveaneffectofvelocityondevelopmentrates.Thus,decreasingflowswilldecreasedriftdistanceduringembryonicdevelopment.However,theeffectsofflowregulationonhabitatavailabilityshouldbecarefullyconsideredashabitatavailabilitymayalsoeffectdriftdistances.
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TABLES
TableI.Averagevelocitiesandstandarddeviations(inparenthesis)ofthethreevelocitytreatmentsintheVelocity×Temperatureexperimentsexaminingtheeffectoftemperatureandvelocityonpallidsturgeonlarvaldevelopment.Positivevelocityisintheclockwisedirection.Bottomvelocitiesweremeasured3cmabovethebottomofthetankandaveragevelocitiesweremeasuredat0.6×waterdepth.
Treatment(cm/s) Bottomvelocity(cm/s) Averagevelocity(cm/s)
0 -4.6(0.5) -0.25(0.7)
10 6.9(1.4) 10.3(1.3)21 17.3(2.4) 20.8(1.9)
TableII.Listofresponsevariablesexaminedineachlarvalpallidsturgeonexperimentandtheirassociatedexplanatoryvariables.
ResponseVariable Experiment ExplanatoryVariables
Presenceoffood Velocity×Temperature Age,length,temperature,velocity
Length(mm) Velocity×Temperature Age,temperature,velocityYolksacarea(mm2) Velocity×Temperature Age,length,temperature,velocity
Ucrit(cm/s) Smallswimchamber;Ucrit Age,lengthUcrit(BL/s) Smallswimchamber;Ucrit Age,lengthUsprint(cm/s) Largeswimchamber;Usprint Age,fincurl,length,tankUsprint(BL/s) Largeswimchamber;Usprint Age,fincurl,length,tank
Metrics:Age(daysposthatch),fincurl(qualitativescaleofpercentageofoutsideedgeofpectoralfinaffected),length(mm;totallength),tank(holding/rearingenvironment),temperature(°C),Ucrit/Usprint(cm/sandbodylengths/s)andvelocity(cm/s).
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TableIII.Age(daysposthatch),cumulativethermalunitsfromhatch(CTU,fromhatch),andtotallength(mm)forimportantdevelopmentalfeaturesofpallidsturgeonfreeembryos/larvaeintheVelocity×Temperatureexperiments.Resultsfrom15and20°Ctreatmentspresented;nodifferencesamongvelocitytreatmentswasobserved.Age,CTU,andlengthpresentedasarange(min,max)fromthefirstobservationtowhenthedevelopmentalfeaturewasobservedinallsampledindividuals.
ResponseVariable Age CTU Length(mm)a
15 20 15 20 15 20
Hatchb 0 0 0 0 7.2,8.9 7.6,8.9
Presenceoffoodc 18,23 10,13 275,352 205,268 18.8,18.5 19.6,20.3Absenceofmelaninplug 15,18 8,10 230,275 163,205 18.2,18.5 18.8,19.7
Absenceofyolksac 15,17 9,10 230,260 184,205 17.9,18..5 18.8,19.7Bottomorientation 11d 6,9 168 122,184 16.5 16.7,18.3
a Lengthvaluesrepresenttheaverageofallindividualswiththepresenceofdevelopmentalfeatureonthefirstdaythefeaturewasobservedandthedaywhenthefeaturewasobservedfor“all”larvaeb HatchatlengthispresentedastheminimumandmaximumlengthsobservedforsampledembryoscFoodwasneverobservedforalllarvae.Therangepresentedisthefirstobservationoffoodtothepredictedpeakproportionoflarvaewithfoodpresentinstomachsfromlogisticregression.dNopeakobservedforfishorientedonthebottomforthe15°Ctreatments,onlyvaluesforthefirstobservationofbottomorientationpresented
TableIV.Regressiontableforrelationshipsamonglength,yolksacarea,Ucrit,Usprint,age,temperature(T),velocity,andholdingenvironment(‘tank’)fromlarvalpallidsturgeonVelocity×Temperature,Ucrit,andUsprintexperiments.A“×”isusedtoindicateinteractionsbetweenvariables.
Responsevariable Explanatoryvariable β(±SE) t P-valueProbability ofpresenceoffood
interceptage -5.42(0.45)0.19(0.02)
12.19.8
<0.0001<0.0001
T20 -1.43(0.87) 1.6 0.10
age×temperatureLogisticregression
0.50(0.07) 6.9 <0.0001
Probability ofpresenceoffood
interceptlength -14.60(1.80)0.73(0.10)
8.17.4
<0.0001<0.0001
T20 -14.48(4.00) 3.7 0.0003
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length×temperatureLogisticregression
0.83(0.21) 3.9 <0.0001
Length intercept 8.4(0.12) 71.9 <0.0001
age 0.9(0.02) 34.8 <0.0001
T20 -1.2(0.22) 5.5 <0.0001
age×T20 1.0(0.08) 12.8 <0.0001
age2 -0.02(0.001) 14.2 <0.0001
age2×T20 -0.05(0.007) 6.8
F5,607=2727.1;adjustedr2=0.96;P<0.0001
<0.0001
Yolksacarea intercept 7.00(0.08) 82.9 <0.0001 age -0.42(0.01) 52.9 <0.0001
T20 -0.13(0.15) 0.9 0.38
T20×age -0.29(0.02) 12.5F3,508=1288.4;adjustedr2=0.88;P<0.0001
<0.0001
Yolksacarea intercept 13.41(0.25) 54.7 <0.0001
length -0.70(0.02) 43.5 <0.0001
T20 -2.37(0.40) 6 <0.0001
T20×length 0.17(0.03) 6.8F3,508=861.4;adjustedr2=0.84;P<0.0001
<0.0001
ln(Ucrit)-Absolute intercept 2.19(0.07) 32.26 <0.0001
age 0.03(0.003) 8.22F1,115=67.5;adjustedr2=0.36;P<0.0001
<0.0001
ln(Ucrit)-Absolute intercept 2.17(0.06) 34.88 <0.0001
length 0.02(0.002) 9.27F1,115=85.9;adjustedr2=0.42;P<0.0001
<0.0001
Ucrit-Relative intercept 8.02(0.41) 19.59 <0.0001
age -0.09(0.02) 4.96F1,115=24.6;adjustedr2=0.17;P<0.0001
<0.0001
Ucrit-Relative intercept 8.26(0.38) 21.84 <0.0001
length -0.08(0.01) 6.06F1,115=36.7;adjustedr2=0.24;P<0.0001
<0.0001
Usprint-Absolute intercept 14.73(17.33) 0.85 0.4
age 0.34(0.25) 1.36 0.18
fincurl 1.32(0.93) 1.41 0.16
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tank 5.34(2.17)F3,71=4.3;adjustedr2=0.12;P=0.008
2.47 0.02
Usprint-Absolute intercept -4.94(5.92) 0.83 0.41
length 0.49(0.06) 8.09 <0.0001
fincurl 0.75(0.66) 1.14 0.26 tank 4.36(1.57) 2.77 0.007 F3,71=28.7;adjustedr2=0.53;P<0.0001
Usprint-Relative intercept 3.55(1.38) 2.6 0.01
age 0.01(0.02) 0.6 0.58 fincurl 0.07(0.07) 1 0.33
tank 0.45(0.17)F3,71=3.1;adjustedr2=0.08;P=0.03
2.7 0.01
Usprint-Relative intercept 4.01(0.64) 6.3 <0.0001
length 0.03(0.06) 0.5 0.62 fincurl 0.08(0.07) 1.1 0.29
tank 0.46(0.17)F3,71=3.1;adjustedr2=0.08;P=0.03
2.7 0.009
Metrics:Age(daysposthatch),fincurl(qualitativescaleofpercentageofoutsideedgeofpectoralfinaffected),length(mm;totallength),tank(holding/rearingenvironment),temperature(°C),absoluteUcrit/Usprint(cm/s),relativeUcrit(bodylengths/s),velocity(cm/s),andyolksacarea(mm2).T20iscategoricalvariableequalto1for20°Ctreatmentsand0forthe15°
Ctreatmentsandtankisequalto1forfishheldintheartificialriverand0forfishheldinthe1.8mcirculartank.
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FIGURES
Figure1.Photographicguideofpallidsturgeonembryonicdevelopment1-7daysposthatch(dph)forembryosrearedat15and20°CfromtheVelocity×Temperatureexperiments.Examplesoftotallengthandyolksacareameasurementsaredenotedbywhitelines.Therewasnoevidenceforarelationshipbetweenvelocityandlengthoryolksacarea.
Note:Localcontrastenhancedinphotographtofacilitateidentificationofdevelopmentalfeatures.
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Figure2.Photographicguideofpallidsturgeonembryonicdevelopment9-15daysposthatch(dph)forembryosrearedat15and20°CfromtheVelocity×Temperatureexperiments.Examplesoftotallengthandyolksacareameasurementsaredenotedbywhitelines.Yolksacwasnolongerexternallyvisible15dphand9dphat15and20°C,respectively.Therewasnoevidenceforarelationshipbetweenvelocityandlengthoryolksacarea.
Note:Localcontrastenhancedinphotographtofacilitateidentificationofdevelopmentalfeatures.
15 ° C 20 ° C
9 dph
11 dph dph
dph 13
dph 15
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Figure3:Photographoftheartificialriverusedinobservationalpallidsturgeonlarvaldriftexperiment.
Figure4.Planviewofartificialriveridentifyingimportantstructuresandfeatures.
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Figure5:Substratemapoftheartificialriver.
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Figure6.LogisticcurvesdescribingtherelationshipbetweentheprobabilityofthepresenceoffoodandageofpallidsturgeonintheVelocity×Temperatureexperimentforthe15(T15)and20°C(T20)treatments.Therewasnoevidenceforarelationshipbetweentheprobabilityofthepresenceoffoodandvelocity
Note:Alllarvaeweredeceasedby21dphinthe20°Ctreatment.
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Figure7.Logisticcurvesdescribingtherelationshipbetweentheprobabilityofthepresenceoffoodandlength(mm)ofpallidsturgeonintheVelocity×Temperatureexperimentforthe15(T15)and20°C(T20)treatments.Therewasnoevidenceforarelationshipbetweentheprobabilityofthepresenceoffoodandvelocity.
Figure8.Relationshipbetweenpallidsturgeonlength(mm)anddaysposthatchfortheVelocity×Temperaturetreatments.TemperaturetreatmentsaredenotedT15(15°C)andT20(20°C).Therewasnoevidenceforarelationshipbetweenlengthandvelocity.Regressioncurveswerecalculatedfromareduceddatasetconsistingofdayposthatchbeforethemelaninplugwasshed(18and10dphfor15and20°Ctreatments,respectively).
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Figure9.Relationshipbetweenpallidsturgeonyolksacarea(mm2)anddaysposthatchfortheVelocity×Temperaturetreatments.TemperaturetreatmentsaredenotedT15(15°C)andT20(20°C).Therewasnoevidenceforarelationshipbetweenyolksacareaandvelocity.Regressioncurveswerecalculatedfromareduceddatasetconsistingofdayposthatchwhileexternallyvisibleyolksacwasvisible(17and10dphfor15and20°Ctreatments,respectively).
Figure10.Relationshipbetweenpallidsturgeonyolksacarea(mm2)andlength(mm)fortheVelocity×Temperaturetreatments.TemperaturetreatmentsaredenotedT15(15°C)andT20(20°C).Therewasnoevidenceforarelationshipbetweenvelocityandyolksacarea.Regressioncurveswerecalculatedfromareduceddatasetconsistingofdayposthatchwhileexternallyvisibleyolksacwasvisible(17and10dphfor15and20°Ctreatments,respectively).
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Figure11.DailymortalityratesinthesixVelocity×Temperatureobservationtanks.Deceasedpallidsturgeonwerereplaceddailyaftermortalitycountstomaintainasamplesizeoften.
Days post hatch Days post hatch
Days post hatch Days post hatch
Days post hatch Days post hatch
0 5 10 15 20 25 30 0.0 0.2 0.4 0.6 0.8 1.0
Dai
ly m
orta
lity
rate
5 10 15 20 0.0 0.2 0.4 0.6 0.8 1.0
Dai
ly m
orta
lity
rate
15 °C × 0 cm/s 20 °C × 0 cm/s
0 5 10 15 20 25 30
0.0 0.2 0.4 0.6 0.8 1.0
Dai
ly m
orta
lity
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5 10 15 20
0.0 0.2 0.4 0.6 0.8 1.0
Dai
ly m
orta
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15 °C × 1 0 cm/s 20 °C × 1 0 cm/s
0 5 10 15 20 25 30
0.0 0.2 0.4 0.6 0.8 1.0
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5 10 15 20
0.0 0.2 0.4 0.6 0.8 1.0
Dai
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Figure12.Contourvelocitymapoftheartificialriver.Eachvelocitymeasurement(n=6588)represent30sfixedpointaveragestaken3cmabovethesubstrate.
Figure13.RelationshipbetweenabsoluteUcrit(cm/s;n=117)andA)age(daysposthatch;R2=.36)andB)length(cm;R2=0.42)forlarvalpallidsturgeon.
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Figure14.RelationshipbetweenrelativeUcrit(Bodylengths/s;n=117)andA)age(daysposthatch;R2=0.17)andB)length(cm;R2=0.24)forlarvalpallidsturgeon.
Figure 15. Relationship between absolute Usprint (cm/s; n=75) and fish length (TL, cm; R2=0.53) for fish held in a 1.8 m circular tank and 20 m (circumference) oval artificial river.
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GeneticIdentificationofLarvalSturgeonfrom2016UpperMissouriRiverLarvalDriftStudy
FinalReportDecember12,2017
MontanaFish,Wildlife&Parks Contract:FWP#17-599
Submittedto:
StateofMontana Fish,Wildlife&Parks
1AirportRd. Glasgow,MT
59230
EdHeist,RachelGockerandAmyBuhman SouthernIllinoisUniversityCarbondale
CenterforFisheries,Aquaculture&AquaticSciences LifeSciencesIIRoom251
1125LincolnDrive Carbondale,IL62901
Introduction,MaterialsandMethods PatBraatenoftheU.S.GeologicalSurvey,FortPeckoffice,provided1269acipenseridfreeembryosand411youngoftheyear(YOY)larvaeaspartofthe2016upperMissouriRiverlarvaldriftstudy.FreeembryosandYOYweregeneticallyidentifiedfollowingtheprotocolsofEichelbergeretal.(2014)withsomemodifications.TissuesampleswerefirstdigestedusingAppliedBiosystemsSample-to-SNPkit.Becausepaddlefishandsturgeonfreeembryosaremorphologicallyindistinguishable,freeembryoswerefirstgenotypedatamitochondrialSingleNucleotidePolymorphism(SNP)thatdistinguishesbetweenpaddlefishandsturgeon(Heist,unpublished).Freeembryospossessingthenucleotide“A”attheSNPwereidentifiedassturgeon,whilethosewithnucleotide“G”wereidentifiedaspaddlefish.FreeembryosthatwereidentifiedassturgeonandsturgeonYOYwereanalyzedatoneortwonuclearSNPlociforwhichnearlyallpallidsturgeonarehomozygousforanallelethatisrareinshovelnosesturgeon.Atleast95%ofpallidsturgeonfromtheMissouriRiverpossessgenotype“GG”forSNPlocusRAG-1Aandgenotype“AA”forSNPlocusIGF-2B.Onlyabout2%ofshovelnosesturgeonpossessbothofthesegenotypes.WefirstscreenedforlocusRAG-1Aandifthelarvaorfreeembryohadgenotype“GG”we
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thenscreenedforlocusIGF-2B.Anylarvaorfreeembryothathadgenotype“GG”forlocusRAG-1ASNPlocusandgenotype“AA”forSNPlocusIGF-2Bwasconsidereda“potentialpallid”andwasidentifiedtospeciesusingDNAmicrosatellites.Freeembryosandlarvaeidentifiedas“potentialpallids”weregenotypedat19DNAmicrosatellitelocifollowingtheprotocolsofSchreyetal.(2011).Todeterminewhethereachspecimenwasapurepallidsturgeon,pureshovelnosesturgeon,orahybridweusedtheNewHybridssoftwarepackageofAndersonandThompson(2002)usinglocalbaselineallelefrequenciesforpallidandshovelnosesturgeon.Thebaselinesturgeonwerepreviouslyidentifiedusingacombinationofmolecularanalysisandmorphologicaldataandincludes175pallidsturgeonand128shovelnosesturgeonfromtheGreatPlainsManagementUnit.Afishwasidentifiedasapurepallidsturgeonifit’sprobabilityofassignmenttothepurepallidsturgeoncategorywas≥0.95.WeusedtheCervussoftwarepackageofKalinowskietal.(2007)toidentifytheparentageofpallidsturgeonfreeembryosandYOYbasedontheparentalgenotypesandknowncrossesamongthe7femaleand9malepallidsturgeonbroodstockusedtoproducethefreeembryosforthedriftstudy.
ResultsSNPanalysesidentified74freeembryosas“potentialpallids,”559asshovelnosesturgeon,634aspaddlefish,and2freeembryosfailedtoproducesufficientDNAforreliableanalyses(Appendix1).58ofthepotentialpallidswereamongthe90freeembryosfrombox1withtheremaining14distributedamongthe1179freeembryosintheremaining14boxes.AnalysisofmicrosatellitedatausingNewHybridsrevealedthatall58“potentialpallids”frombox1werepallidsturgeonwhiletheremaining14wereshovelnosesturgeon(Table1).Parentageanalysisidentifiedallpallidsturgeonfreeembryosasoffspringofthe7femaleand9malebroodstockparents.Therewasstrongcorrespondencebetweenthenumberofembryosstockedperfamilyandthenumberrecovered(datanotshown),althoughtwoofthefreeembryosmatchedcrossesbetweenparentsusedtoproducethefreeembryosbutincrossesthatwerenotdocumented(Table2).SNPanalysesidentified7ofthe452YOYas“potentialpallids,”443asshovelnosesturgeon,and2samplesfailedtoproducesufficientDNAforreliableanalyses(Appendix2).All9ofthe“potentialpallid”YOYwereidentifiedasshovelnosesturgeon(Table3).
LiteratureCitedAndersonEC,ThompsonEA(2002)Amodel-basedmethodforidentifyingspecieshybridsusing
multilocusgeneticdataGenetics,160,1217-1229.EichelbergerJS,BraatenPJ,FullerDB,KrampeMS,HeistEJ(2014)NovelSingle-Nucleotide
PolymorphismMarkersConfirmSuccessfulSpawningofEndangeredPallidSturgeonintheUpperMissouriRiverBasin.TransAmFishSoc,143,1373-1385.
KalinowskiST,TaperML,MarshallTC(2007)RevisinghowthecomputerprogramCERVUS
accommodatesgenotypingerrorincreasessuccessinpaternityassignment.MolEcol,16,10991106.
SchreyAW,BoleyR,HeistEJ(2011)HybridizationbetweenpallidsturgeonScaphirhynchusalbusand
shovelnosesturgeonScaphirhynchusplatorynchus.JFishBiol,79,1828-1850.
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Table1.NewHybridsanalysisof72“potentialpallids.”Dataincludeboxnumber,IndividualID,Newhybridprobabilitiesthatafreeembryoisapurepallidsturgeon(Pal),hybrid(Hyb),orshovelnose(Sho)sturgeonandspeciesID.Box ID Pal Hyb Sho Species
1 0091 1.000 0.000 0.000 Pallid
1 0104 1.000 0.000 0.000 Pallid
1 0105 1.000 0.000 0.000 Pallid
1 0652 1.000 0.000 0.000 Pallid
1 0668 1.000 0.000 0.000 Pallid
1 0794 1.000 0.000 0.000 Pallid
1 0795 1.000 0.000 0.000 Pallid
1 1849 1.000 0.000 0.000 Pallid
1 0092-A 1.000 0.000 0.000 Pallid
1 0092-B 1.000 0.000 0.000 Pallid
1 0095-A 1.000 0.000 0.000 Pallid
1 0095-B 1.000 0.000 0.000 Pallid
1 0096-A 1.000 0.000 0.000 Pallid
1 0096-B 1.000 0.000 0.000 Pallid
1 0096-C 1.000 0.000 0.000 Pallid
1 0097-A 1.000 0.000 0.000 Pallid
1 0097-B 1.000 0.000 0.000 Pallid
1 0098-A 1.000 0.000 0.000 Pallid
1 0098-B 1.000 0.000 0.000 Pallid
1 0098-C 1.000 0.000 0.000 Pallid
1 0101-A 1.000 0.000 0.000 Pallid
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1 0101-B 1.000 0.000 0.000 Pallid
1 0102-A 1.000 0.000 0.000 Pallid
1 0102-B 1.000 0.000 0.000 Pallid
1 0102-C 1.000 0.000 0.000 Pallid
1 0103-A 1.000 0.000 0.000 Pallid
1 0103-B 1.000 0.000 0.000 Pallid
1 0103-C 1.000 0.000 0.000 Pallid
1 0777-A 1.000 0.000 0.000 Pallid
1 0777-B 1.000 0.000 0.000 Pallid
1 0777-C 1.000 0.000 0.000 Pallid
1 0777-D 1.000 0.000 0.000 Pallid
1 0777-E 1.000 0.000 0.000 Pallid
1 0777-F 1.000 0.000 0.000 Pallid
1 0777-H 1.000 0.000 0.000 Pallid
1 0777-I 1.000 0.000 0.000 Pallid1 0777-J 1.000 0.000 0.000 Pallid1 0784-A 1.000 0.000 0.000 Pallid1 0784-B 1.000 0.000 0.000 Pallid1 0784-C 1.000 0.000 0.000 Pallid1 0784-D 1.000 0.000 0.000 Pallid1 0784-E 1.000 0.000 0.000 Pallid1 0784-F 1.000 0.000 0.000 Pallid1 0784-G 1.000 0.000 0.000 Pallid1 0784-H 1.000 0.000 0.000 Pallid1 0785-A 1.000 0.000 0.000 Pallid1 0785-B 1.000 0.000 0.000 Pallid1 0785-C 1.000 0.000 0.000 Pallid1 0785-D 1.000 0.000 0.000 Pallid1 0785-E 1.000 0.000 0.000 Pallid1 0785-F 1.000 0.000 0.000 Pallid1 0785-G 1.000 0.000 0.000 Pallid1 1847-A 1.000 0.000 0.000 Pallid1 1847-B 1.000 0.000 0.000 Pallid1 1847-C 1.000 0.000 0.000 Pallid1 1848-A 1.000 0.000 0.000 Pallid
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1 1848-B 1.000 0.000 0.000 Pallid1 1848-C 1.000 0.000 0.000 Pallid3 1171 0.000 0.018 0.982 Shovelnose5 1834 0.000 0.001 0.999 Shovelnose5 1837 0.000 0.001 0.999 Shovelnose5 2037 0.000 0.188 0.812 Shovelnose6 0077-B 0.000 0.000 1.000 Shovelnose6 0078-D 0.000 0.001 0.999 Shovelnose8 2098 0.000 0.021 0.979 Shovelnose8 0390-J 0.000 0.001 0.999 Shovelnose9 0676-B 0.000 0.002 0.998 Shovelnose11 2214 0.000 0.002 0.998 Shovelnose12 1530 0.000 0.001 0.999 Shovelnose12 2253-A 0.000 0.000 1.000 Shovelnose15 0360-A 0.000 0.000 1.000 Shovelnose15 0429-A 0.000 0.002 0.998 ShovelnoseTable2.ParentageofpallidsturgeonfreeembryosincludingsampleIDandPITtagsoffemaleandmaleparents.Twofishmarkedwithasteriskappeartobeoffspringofparentsusedforthestudybutfromacrossthatwasnotdocumented.ID Female Male
0105 115557165A 132313521A
0652 115557165A 132313521A
1849 115557165A 132313521A
0095-B 115557165A 132313521A
0096-B 115557165A 132313521A
0103-B 115557165A 132313521A
0777-D 115557165A 132313521A
0777-J 115557165A 132313521A
0784-B 115557165A 132313521A
0785-B 115557165A 132313521A
0785-C 115557165A 132313521A
1847-B 115557165A 132313521A
1847-C 115557165A 132313521A
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1848-B 115557165A 132313521A
1848-C 115557165A 132313521A
0668 115557165A 411D0B4E09
0777-I 115557165A 411D0B4E09
0785-A 115557165A 411D0B4E09
1847-A 115557165A 411D0B4E09
0104 1F497F1801 0A180E0E7E
0092-A 1F497F1801 0A180E0E7E
0102-A 1F497F1801 0A180E0E7E
0102-C 1F497F1801 7F7D7C2447
0103-C 470378405D 132313521A *
0097-B 470378405D 220F107A6F
0098-B 470378405D 220F107A6F
0101-B 470378405D 220F107A6F
0777-A 470378405D 220F107A6F
0777-B 470378405D 220F107A6F
0777-C 470378405D 220F107A6F
0784-D 470378405D 220F107A6F
0784-F 470378405D 220F107A6F
0096-A 470378405D 411D0B4E09
0102-B 470378405D 411D0B4E09
0103-A 470A675627 7F7D7C2447 *
0091 470A675627 7F7F065834
0794 470A675627 7F7F065834
0795 470A675627 7F7F065834
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0092-B 470A675627 7F7F065834
0095-A 470A675627 7F7F065834
0096-C 470A675627 7F7F065834
0097-A 470A675627 7F7F065834
0098-A 470A675627 7F7F065834
0098-C 470A675627 7F7F065834
0101-A 470A675627 7F7F065834
0777-F 470A675627 7F7F065834
0784-A 470A675627 7F7F065834
0784-C 470A675627 7F7F065834
0784-G 470A675627 7F7F065834
0784-H 470A675627 7F7F065834
0785-D 470A675627 7F7F065834
0785-E 470A675627 7F7F065834
0785-F 470A675627 7F7F065834
0785-G 470A675627 7F7F065834
0777-E 7F7FD66963 132313521A
0777-H 7F7FD66963 132313521A
0784-E 7F7FD66963 132313521A
1848-A 7F7FD66963 132313521A
Table3.NewHybridsanalysisof9“potentialpallid”YOY.Dataincludeboxnumber,IndividualID,Newhybridprobabilitiesthatafreeembryoisapurepallidsturgeon(Pal),hybrid(Hyb),orshovelnose(Sho)sturgeonandspeciesID.Sample Pal Hyb Sho Species0967 0.000 0.002 0.998 Shovelnose1068 0.000 0.002 0.998 Shovelnose1085 0.000 0.001 0.999 Shovelnose
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1341 0.000 0.001 0.999 Shovelnose1596 0.000 0.001 0.999 Shovelnose2308 0.000 0.013 0.987 ShovelnoseSTURG-4800A 0.000 0.001 0.999 ShovelnoseNOTE:TheappendicestothisreporthavebeendeletedtolimitthelengthoftheAnnualReport.Acopyofthecompletereportcanbemadeavailableonrequest.9BobSnyder,UpperBasinWorkgroupFacilitator)
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OtherSIUCUpperBasinProjects
Dr.Heist’slabatSouthernIllinoisUniversityCarbondaleidentified1267acipenseriformfreeembryosand450sturgeonyoungoftheyear(YOY)aspartofthe2016upperMissouriRiverdriftstudy.Ofthe1267freeembryos,543wereidentifiedasshovelnosesturgeon,634aspaddlefish,and58aspallidsturgeon.Allofthepallidsturgeonwereoffspringofbroodstockparentsusedtoproduceembryosforthedriftstudy.AlloftheYOYwereidentifiedasshovelnosesturgeon.
Dr.HeistalsobeganaWAPA-fundedstudytoidentifytheoptimumprotocolandtheearliestlifestagesatwhichsturgeonfreeembryoscouldbegeneticallyidentified.Wetested4commercialkitandidentifiedonewhichproducedthehighestyieldandDNAconcentration.Usingthatkit,hatcheryproducedfreeembryosatstage5failedtoproducesufficientnuclearDNAforamplificationofmicrosatellites,stages7-9producedsomeamplificationbutmanylocifailedandsomecallsappearedquestionable.Stage14freeembryosproducedsufficientDNAforamplifyingallloci.Wearecurrentlyusingparentageanalysistodeterminewhetherthedataproducedfromthestage14freeembryoswerereliableandarealsousingthechosenkittoisolateandamplifyDNAfromstagedwild-caughtfreeembryos.
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DeterminationofReproductiveIndicesinHatchery-originPallidSturgeonintheMissouriandYellowstoneRivers
2017-2018AnnualReport
MollyA.H.Webb
USFWS,BozemanFishTechnologyCenterExecutive Summary: This project will determine the age at sexual differentiation, onset ofpubertyand firstmaturity,andspawningperiodicityofhatchery-origin (HO)pallid sturgeon inthe Missouri and Yellowstone rivers using known-aged juvenile pallid sturgeon. Millions ofdollarsandconsiderableeffortforendangeredpallidsturgeonintheupperbasinoftheMissouriRiver has beenplaced in the conservationpropagationprogram to prevent extirpationof thespecies. Hundredsof thousandsofpallidsturgeonyoung-of-yearhavebeenreleased into theupperMissouriRiversince1998.Thosefisharenowreachingsexualmaturityasdeterminedbycirculatingsexsteroidconcentrations.Astheheritagefishageanddie,wewillbereliantontheHOpallidsturgeontomaintainthespecies.UnderstandingwhethertheHOpallidsturgeonarecapableofreestablishmentthroughnaturalspawningisvitaltotherecoveryprogram.Since 2009, 986 plasma samples from HO pallid sturgeon captured in the Missouri andYellowstonerivershavebeenanalyzedtodetermineage-at-maturity.The1997andolderyearclasses provide an opportunity to determine age and size at onset of puberty and spawningperiodicityinpallidsturgeonasthesefisharenowover20yearsold.Sex steroids can be used to determine sex and stage of maturity less invasively in sturgeonspeciescomparedtoothertechniquessuchasbiopsy(WebbandDoroshov,2011;Webbetal.2018).TheobjectiveofthisprojectistoanalyzebloodplasmasexsteroidconcentrationsinHOpallidsturgeonintheupperMissouriandYellowstoneriverstoassignsexandstageofmaturityanddeterminetheageandsizeatsexualdifferentiationandfirstmaturityaswellasspawningperiodicity.Project Status/Anticipated/Expected Date of Completion: This project was completed inMarch2018.Analysisof986pallidsturgeonplasmasamplesisreportedhere.Accomplishments/Recommendations/Results:MethodsBloodplasmasamplesfromHOpallidsturgeonthathavebeenanalyzedtodatefortestosterone(T)andestradiol(E2)concentrationswerecollectedfrom:RPMA1byMontanaFishWildlifeandParks (MTFWP) personnel in the Spring and Fall of 2011, 2012, 2013, 2014, 2015, 2016, and2017;RPMA2ontheMissouriRiverbyUSFWSpersonnel inSpringof2010,2011,2015,2016,2017andFall2011,2012,2014,2015,2016,and2017;RPMA2ontheMissouriRiverbyMTFWPinSpringandFallof2012,2014,2015,2016,and2017;RPMA2ontheYellowstonebyMTFWPinSpring2014,2015,2016,2017andFall2011,2013,2014,2015,2016,and2017;RPMA3byUSFWSpersonnelinSpring2012,2013,2014,and2016.CapturelocationontheMissouriRivervaried between river mile (RM) 1880 and 2050 for RPMA 1, between RM 1533 and 1762 inRPMA2,andbetweenRM828and831inRPMA3.CapturelocationontheYellowstoneRivervaried between RM 8 and 70. Blood samples were collected from the caudal vasculature,centrifugedtoseparateplasma,frozen,andsenttotheBozemanFishTechnologyCenter(BFTC)
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for analysis of plasma T and E2 concentrations. Blood plasma steroid concentrations weremeasuredbyradioimmunoassayfollowingthemethodsdescribedinFitzpatricketal.(1986)andmodifiedbyFeistetal.(1990).ResultsandDiscussionBloodplasmaT and E2 concentrations havebeen analyzed in a total of 986 samples to date.Theyoungestyearclasstobesampledwas2011(age2attimeofcapture)andtheoldestwas1997 (age 20 at time of capture). In the 2017 dataset, five reproductive HO males wereidentified.Thesefivemaleswerefromthe1997,2002,and2006yearclasses.Ofthefivemales,twowerecapturedinRPMA1,andthreewerecapturedinRPMA2.Fishageswere20forthe1997yearclass,15forthe2002yearclass,and11forthe2006yearclass.Bodysizerangedfrom950-1215 cm fork length and 5.3-8.7 kg body weight. Four HO reproductive females wereidentifiedin2017.Twofemaleswereripeinthespring,andtwofemaleswerecapturedinthefallandshouldberipein2018.Threefemaleswerefromthe1997yearclass,andonefemalewasfromthe2004yearclass(13yearsoldatcapture;tobe14yearsoldinthe2018spawningseason).The2004yearclassfemalewascapturedinthefall.Bodysizewas1170and1185cmforklengthand7.6and8.3kgbodyweightforthetwofemalescapturedinthespring.Bodysizewas1075and1078cmforklengthand5.6and5.9kgbodyweightforthetwofemalescapturedinthefall.In2017,FemaleF136Dfromthe2004yearclasswascapturedbyMatRuggandhiscrewinthefall and assigned as a ripe female using plasma sex steroids. It would be very beneficial torecapturethisfemaleandcollectbothbloodplasmaandovarianfolliclesinthe2018spawningseason. Shewould be the youngest pallid sturgeon to spawn in our dataset at an age of 14years.TheyoungestHOmaletoshowsignsofreproductivematurityhasbeendocumentedattheageof10asseenbyplasmaTconcentrationsabove38ng/ml.AllothermatureHOmaleshavebeen14yearsorolder.RecaptureofCode83,91,and100inthespringof2018willprovidevaluablespawningperiodicityinformation.Since2011,usingbothdatafromHolmquistetal.(InReview)andthisstudy,wehavebeenableto determine the spawning periodicity in 8 HO males. Six males have had an annualreproductive cycle, and twomales have had binennial cycles.More information needs to becollectedovertimetodeterminespawningperiodicityinfemales.Dummyruns,inwhichfishproduceovarianfolliclesbutdonotovulateandovipositduringtheirfirst cycle, have been described in other long lived species such as rockfish and cod. Massfollicularatresiaistheresult.Thedummyrunmay'condition'gonadsandotherorgansthroughthe elevation of circulating hormones, which would, upon subsequent hormone exposure,decrease the cellular response time, rate of target receptor upregulation and binding proteinsynthesis. This process is similar to the immune response, where physiological “learning”primesthesystemforasubsequentresponsefollowingfirstexposuretothephysiologicalevent.All of the HO ripe females followed in this study to date have undergone follicular atresiaindicating a potential of a dummy run in pallid sturgeon females. There is great value infollowingthereproductivefateofthosefemalesinsubsequentcyclestodetermineiffollicularatresia may be attributed to a dummy run or lack of environmental conditions suitable forspawning.
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ReferencesFeist,G.,C.B.Schreck,M.S.Fitzpatrick&J.M.Redding.1990.Sexsteroidprofilesofcohosalmon(Oncorhynchus kisutch) during early development and sexual differentiation. General andComparativeEndocrinology80:299-313.Feist, G., J.P. Van Eenennaam, S.I. Doroshov, C.B. Schreck, R.P. Schneider, &M.S. Fitzpatrick.2004. Early identification of sex in cultured white sturgeon, Acipenser transmontanus, usingplasmasteroidlevels.Aquaculture232:581-590.Fitzpatrick,M.S., G. Van Der Kraak & C.B. Schreck. 1986. Profiles of plasma sex steroids andgonadotropin in coho salmon,Oncorhynchus kisutch, during final ovarianmaturation.GeneralandComparativeEndocrinology62:437-451.Holmquist, L.M., C.S. Guy, A. Tews,&M.A.H.Webb. In Review. Firstmaturity and spawningperiodicity of hatchery-origin pallid sturgeon in the upper Missouri River above Fort PeckReservoir,Montana.JournalofAppliedIchthyology.Webb,M.A.H.& S.I. Doroshov. 2011. Importance of environmental endocrinology in fisheriesmanagementandaquacultureof sturgeons.GeneralandComparativeEndocrinology170:313-321.Webb,M.A.H,VanEenennaam,J.P.,Crossman,J.A.,&Chapman,F.A.2018.Apracticalguideforassigningsexandstageofmaturityinsturgeonsandpaddlefish.JournalofAppliedIchthyology,00,1-18.https://doi.org/10.1111/jai.13582
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2017PallidSturgeonPropagationActivitiesforGavinsPointNFH
Introduction
In1993ThePallidSturgeonRecoveryPlanprovideddirectionforpropagation,researchneeds,collectionofwildfishandreintroductionofpallidsturgeontoaugmentrecoveryefforts.Productionofwildandcaptiveheldpallidsturgeonwassuccessfulin2017producing502,829eggsfrom11captivefemalesand8wildbroodfish.Atotalof47wildadultsofmiddlebasinoriginweretransferredtoGavinsPointNFHfromSeptember2016toApril2017,withthehelpofmultipleagencies.
CaptiveBroodStockProduction
GavinsPointNFHiscurrentlyrearing1,904captivepallidsturgeonbroodfishthatrepresent20yearclassesasabackupgeneticpoolforuseinsupplementingwildpopulationsandresearchneeds.These1904progenyheldinrefugerepresent146wildindividualsfromupperbasinspawns.These146individualsrepresent154uniquefamilycrosses.
CaptiveBroodStockSpawning
In2017therewerethreespawningeventsinvolving11femalesand8males.Fourdifferentstudieswereconductedusingtheeggsfromthesefish.ThefirststudywasconductedbyUSGS-Yanktonwherenewlyhatchedembryoswereplacedintomesocosmstolookatearlylifestagebehavior,specificallylarvaldrift.Thesecondspawningconsistedof6femalesand4males.Theeggsproducedfromthisroundofspawningwereusedfortwostudies.ThefirstwasagenomicsstudywhereresearchersfromUSGSandSouthernIllinoisweretryingtosequencepallidsturgeonDNA.Thisisdonebyusinguvtreatedpaddlefishmilttofertilizeviablepallideggs,thusmakingatruehaploidoffspringwithonlythemothersDNA.Thesecondstudywasanearlylifestagestudyconductedbyre-searchersatBozemanFishTechnologyCenter(BFTC).Thelastspawningeventutilized4femalesand3males.TheeggsproducedfromthisstudyweretransferredtoBFTCtoagainbeusedinanearlylifestagestudy.Some60,000eggswerekeptandhatchedandondayposthatchtransferredtoSouthDakotaStateUniversitytobeusedforlarvaldriftstudies.
MiddleBasinSpawning
SeveralspawningeventsoccurredatGavinsPointNationalFishHatcheryin2017.OnApril19thafemale(47163E0030)thatwasheldinhatcheryfortwoyears,waspairedwithtwocryo-preservedmales(4626513A54and4627144425).Theyproduced42,750fertilizedeggsat38eggs/ml.Additionally,efforttook41hourstoovulateandtemperaturesrangedfrom55to58°F.
ThesecondspawningeventtookplaceduringApril26th-28thandresultedinsuccessfulspawnof8familylots.Fourfemalesproducedeggs4627463568(28,000),46280F5C1C(33,440),4627545945(27,675)and46274F3A60(20,425)andeightmaleswereused.Female4627463568and46274F3A60werecapturedinthespringof2017.Female46280F5C1Cand4627545945werebothholdoverpallidsturgeonfrompreviousyears.ThePallidSturgeonPITtagged(46280F5C1C)isaspecialcase;in2015itspawnedandproduced5mlofspermwhile5%active
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butwasnotviableenoughforcryo-preservation.Thisfishwasheld-overatthehatcherytomonitoritsprogression.Thenin2016,thefishhadwhiteeggspresentafteranultrasoundwasconducted,thenlaterithaddevelopedandproducedblackeggsin2017.
AthirdspawningeventtookplaceonMay4thwithtwofemalesandfourcryo-preservedmalesBothfemalesproducedfertilizedeggs.Female47160E450Bwascapturedinthefallof2016andproduced26,865eggs.Female462764734Fwascaughtinthespringof2017andproduced6,570eggsin2017.
AfourthspawningeventtookplaceonJune6thwithonefemaleandtwocryo-preservedmales.Female46271E7B23wascapturedinthespringof2017andproduced19930viableeggsthuscreatingtwofamilygroups.
Anothernote,fourfemales(4627463568,46274F3A60,462764734F,46271E7B23)thatallsuccessfullyspawnedwereobservedtohavethespeciesPolypodiumhydriforme;aparasiteknownforattackingfisheggsinsturgeonandpaddlefishspecies.
Inadditiontoeightfemalesbeingsuccessfullyspawned11ofthe12malesthatwerespawnedwerealsocryo-preserved.Themaleindividualswhowerenotcryo-preservedwaskeptatthefacilityandwillbespawnedinafutureyearandenteredintothecryo-repository.
Sixoftheeightfemale’soffspringexperiencedearlylifestagemortalityandthereforethesesixfemaleswillbeheldatthehatcheryandspawnedagainwhenviableeggsareproduced.InJanuaryof2017allwildfishwereassessedforspawningreadinessviaultrasound,whichresultedin3reproductivefemalesand10reproductivemales.Duringthespringcaptureanadditional5reproductivefemalesand2reproductivemaleswerebroughttothehatchery.
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