Delaware 16‐Foot Trawl - Amazon S3...Delaware 16‐Foot Trawl • An increase in the number of...
Transcript of Delaware 16‐Foot Trawl - Amazon S3...Delaware 16‐Foot Trawl • An increase in the number of...
Delaware 16‐Foot TrawlDelaware 16 Foot Trawl
• An increase in the number of juveniles
1 6
1.8Delaware Juvenile (<160mm) Horseshoe Crab Index Juvenile
Trawl Survey
1.0
1.2
1.4
1.6at
ch p
er T
ow
0.4
0.6
0.8
met
ric M
ean
Ca
0.0
0.2
1992
1994
1996
1998
2000
2002
2004
2006
Geo
m
Source: Michels 1 1 1 1 2 2 2 2
VA Tech Horseshoe Crab Trawl Survey –iDE Bay Core Stations
45
50
ow Immature females
• Short time series20
25
30
35
40
Mean Ca
tch / To Multiparous females
Primiparous females
• Improving juvenile abundance is
i0
5
10
15
20
Stratifie
d M
encouraging2001 2002 2003 2004 2005 2006 2007
50
60
h / Tow Immature males
Multiparus males
20
30
40
fied Mean Ca
tch
Primiparous males
Data Source: Hata (2008)Table 4, plotted by Michels0
10
2001 2002 2003 2004 2005 2006 2007
Stratif
DE Bay Spawning Population EstimateDE Bay Spawning Population Estimate
2003 Maximum likelihood estimates2003 Maximum likelihood estimates 2003 Adjusted for relocation rates2003 Adjusted for relocation rates2003 Maximum likelihood estimates2003 Maximum likelihood estimates 2003 Adjusted for relocation rates2003 Adjusted for relocation ratesAbundanceAbundance 90% CI90% CI AbundanceAbundance 90% CI90% CI
MalesMales 16,410,00016,410,000 9,910,000 9,910,000 –– 22,300,00022,300,000 13,730,00013,730,000 8,780,000 8,780,000 –– 19,400,00019,400,000
FemalesFemales 7,350,0007,350,000 4,520,000 4,520,000 –– 10,160,00010,160,000 6,250,0006,250,000 4,000,000 4,000,000 –– 8,840,0008,840,000
TotalTotal 23,490,00023,490,000 14,430,000 14,430,000 –– 32,460,00032,460,000 19,980,00019,980,000 12,780,000 12,780,000 –– 28,240,00028,240,000
• Using these estimates, the Addendum IV harvest would be less than 1% of the DE Bay male spawning
l ti ( / NJ t t i )population (w/ NJ at moratorium)
• Under a complete moratorium the harvest would beUnder a complete moratorium, the harvest would be zero
Source: Smith (2006)
Declining Red Knot Populations are a Principal Management ConcernR
Abundance of horseshoe crab eggs as food during migration linked to red knot condition & likelihood
f f l tiof successful nesting
DE Bay Peak Count - Red Knot 1998-2008
y = -4305.x + 52856R² = 0.848
50 000
60,000
40,000
50,000
nt
20,000
30,000
Cou
0
10,000
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
Year
Source: Kalasz
120 000
DE Bay Peak Count - Ruddy Turnstone 1998-2008
y = -7816.x + 10235R² = 0.848
80 000
100,000
120,000
Source: Kalasz
40,000
60,000
80,000
Cou
nt
0
20,000
40,000
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
Year
Horseshoe Crab Management by the Atlantic States Marine FisheriesAtlantic States Marine Fisheries
Commission
15 member states ME FL15 member states ME‐FL
3 Commissioners per state, although only p , g yone vote/state
1 legislator, 1 governor’s appointee, chief fisheries administratorfisheries administrator
(No wildlife administrators)
ASMFC charged with proposingASMFC charged with proposing and implementing management plans
that conserve the species and prevent overharvest
Initially linked to American eel plan ASMFC passes horseshoe crabplan, ASMFC passes horseshoe crab
management plan in 1998Since 1998, the plan has been
amended 5 times
Coastwide Horseshoe Crab Bait LandingsSource Atlantic States Marine Fisheries Commission
FMPSource, Atlantic States Marine Fisheries Commission
fcrabs)
Millions of
Land
ings (
Delaware LandingsDelaware Landings
• Generally, landings have been 1/3 female and 2/3 male 500
600
Undetermined
Female• ’98, ’99, ’01 landings
approximated to 1:1300
400
SCs
(Tho
usan
ds)
Female
Male Addendum I
Addendum IV
100
200
HS
Addendum III
Addendum IV
0
1991
1993
1995
1997
1999
2001
2003
2005
2007
ASMFC plan passesASMFC plan passes
Proposed Options• ASMFC Compliance with Addendum IV
For 2 Years (October 1, 2006 – September 30, 2008
– Delayed male harvest• Prohibited the directed harvest & landing of all HSCs in NJ & DE from January 1 through June 7 y g
• Prohibited directed harvest of female HSCs from June 8 through December 31.
• Limited NJ & DE harvest to 100,000 HSCs per state.
• Addendum V extended these measures through 2009 with an option for another year
• In 2006 NJ implemented a complete harvest moratorium which remains in effect until changed by legislation
• Prohibits harvest of any HSCs
Delaware installs harvest moratorium January 2007
• Secretary’s ruling challenged by watermen and VA y g g yconch processor.
• On third legal challenge, moratorium overturned by S i C t J 2006Superior Court June 2006.
• Environmental groups attempt to interveneDelaware DF&W adopts emergency regulation‐ Delaware DF&W adopts emergency regulation
consistent with Addendum IV.‐ Adopted by formal regulatory process fall, 2007p y g y p‐ Hundreds of public comments received on draft regulations from all over country
Management Lessons Learned from the Horseshoe Crab Experiencep
•Fisheries management must include ecosystem considerations.
•Non‐traditional users can be very important.
•Politics and/or courts may drive decision making•Politics and/or courts may drive decision making.
•NGOs from environmental community will likely play a role in decision making.