Final Milfoil Report

Lake George Park CommissionLake George Integrated Aquatic Plant Management ProgramPrepared by: Lycott Environmental Inc. Southbridge MA, USA November 2010

Table of ContentsAcknowledgements .... Executive Summary Introduction ..1 History of Aquatic Management Program in Lake George ...1 Process and Participants 1 Figure 1. 2010 Pre-Management Site Status in Lake George ..........................2 Table 1. Lycott 2010 Management Activities ..........7 Figure 2. 2010 Post-Management Site Status in Lake George ..............11 Table 2. FUND 2010 Management Activities....16 Aquatic Plant Management ....17 Table 3. Milfoil Sites by Year.....18 Hand Harvesting .....18 Table 4. Distribution of Effort by Year ....19 Figure 3. Distribution of 2009 Effort ......19 Benthic Barrier....20 Table 5. Distribution of Effort by Year .21 Figure 4. Distribution of 2009 Effort .......21 General Conclusions ..21 Figure 5. Historical Site Densities prior to onset of management by site...23 References ..28 Appendix A. Site Histories Appendix B. 2010 Site Status and 2011 projected management by site. Appendix C. Site GPS Waypoint Data (WGS84) Appendix D. Inventory of In-Lake Barrier Panels 1986-2010 Appendix E. AIM swim-over Map

Acknowledgements

We would like to thank Larry Eichler and all of the staff at Darrin Fresh Water Institute for their much-needed technical and logistical support throughout this project. We also thank the Lake George Park Commission for support in every aspect of this project. In particular we thank Mike White and Roger Smith at the LGPC. RK thanks Julian Barthold, Bryan Becker, Kaitlin Dunn, Samantha Edwards, Erin Miller, Jessy Mortimer James Robianni and Therese Tripler for their hard work and for generally making it an enjoyable project. Valuable logistical support was also gained from the staff at Norowal Marina and many of the DEC staff at Green Island. And we especially thank the crew at Rich Morins Dive Center for their help and often staying open late for us.

Richard King, Ph.D Brittany Laginhas, M.S Lycott Environmental Inc. Southbridge, MA USA

Executive SummaryThis report is prepared on behalf of the Lake George Park Commission which has contracted with Lycott Environmental Inc. to undertake Eurasian Watermilfoil management activities and to record results. Where expressly noted, the report also includes results of activities organized by the Fund for Lake George, Inc. The Lake George Park Commission and the Fund for Lake George Inc. coordinate their activities, provide mutual financial and logistical support, and assemble relevant data into a single final report. In addition to the program expenditures for contractual services reported herein, the Commission expended funds for equipment storage, maintenance and supplies as well as providing significant in-kind staff coordination and supervision. Also in 2010, the Lake George Park Commission provided a grant in the amount of $30,000 to the Fund for Lake George, Inc. which covered a portion of the management activities reported herein. The Commission separately supports invasive spread prevention efforts through its Marine Patrol and also provided a grant in 2010 to the Lake George Association for a portion of the expenses related to a Lake Steward Program, a launch monitoring spreadprevention effort. Eurasian watermilfoil (Myriophyllum spicatum L.) was first documented in Lake George in 1985. Physical plant management of milfoil began in 1986 through volunteer hand harvesting and the placement of benthic barrier. In 1989 suction harvesting was incorporated into the management program with the support of local, state, and federal funding. Federal support for milfoil management ended in 1993. Since 1994 the Lake George Eurasian Watermilfoil Program has been undertaken by the Lake George Park Commission with support from The Fund for Lake George Inc. and in kind service support from Darrin Freshwater Institute. Additionally, beginning 2009 the Fund for Lake George Inc. hired an independent contractor to supplement the Park Commissions project. In the management program, physical plant management techniques form the basis for management activities. Preferred physical management approaches are based on density of milfoil growth. Scattered and moderately dense sites are managed by hand harvesting. Dense growth sites are largely managed with benthic barrier in conjunction with hand harvesting. By the conclusion of the 2010 management effort, a total of 183 Eurasian Watermilfoil sites were identified, four more than documented in 2009. In the southern basin, there are high concentrations of milfoil sites near human population centers and boat-use areas including, but not limited to Lake George Village, Bolton Landing, Harris Bay and Dunham's Bay. In the north basin, clusters of Eurasian watermilfoil sites are also found in areas of high use near Huletts Landing, Putnam, Hague, and throughout the bay at the outlet. A total of 181 milfoil sites have been managed in one or more years since the initial effort in 1986 (though not all efforts were successful). Of these, 171 sites were cleared of Eurasian watermilfoil in 2010. Combining Lycott hand harvesting and benthic barrier data, a total estimated 670,821 plants were removed 2010. Additionally, 270,000+ plants were removed through efforts supported by the FUND. The Lycott data does not

represent a significant difference in work effort from prior years, but rather a modified reporting method. In addition to reporting the number and total size of barrier panels used, plant density measures were gathered at several sites such that the number of plants removed could be calculated and better tracked relative to hand harvesting efforts. Management activities in Lake George have had a positive effect on the control of many milfoil sites. However, nine sites remain with dense milfoil beds, two sites have moderately-dense growth, and one site remains scattered. As of 2010, a total of 171 sites have been successfully cleared or managed. Thus, in addition to routine annual effort, 12 of the 183 total sites in Lake George require significant future effort.

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORT

Introduction The Lake George Park Commission began plant control activities in 1986 with a threeacre benthic barrier installation and volunteer hand-harvesting program. From 1989-1993 physical plant management was performed by Darrin Freshwater Institute (DFWI) under an agreement with the New York State Department of Environmental Conservation. The work was supported by a Federal Clean Lakes Program grant. In 1994 the Lake George Park Commission (LGPC) accepted responsibility for the program as federal funding ended. DFWI continued to provide the management services under an agreement with the LGPC from 1995 through 2001. Since 1994 the LGPC has provided the financial means, administration and permits for the project. Additional support is given by the Fund for Lake George, Inc., and DWFI continues to provide essential data collection and reporting. DFWI concluded their role as primary provider of physical milfoil management in Lake George in 2001. Beginning in 2002, Lycott Environmental Inc. (Lycott) was retained by LGPC to continue the management program through the year 2011. The following report details past and ongoing physical management efforts as well as the current status of milfoil sites in Lake George. Additionally, the Fund for Lake George, Inc. contracted with an independent firm primarily for a targeted, large-scale hand-harvesting effort at a specific sites and geographic areas. Eurasian Watermilfoil Sites As of 2010 season end, a total of 183 Eurasian watermilfoil (Myriophyllum spicatum) sites have been identified in Lake George (Table 1). Approximately half of these sites are located in the southern basin, with high concentrations near human population centers and boat-use areas including: Lake George Village, Bolton Landing, and the southeastern shallow bays (Dunham's, Harris and Warner) (e.g., Figure 1). In the northern basin, clusters of milfoil colonies are also found in areas of high use near Huletts Landing, Putnam, Hague, and the outlet. Figure 1 shows site locations and status prior to 2010 management operations.

1

Figure 1. Map of all known Eurasian watermilfoil sites as of 2010 and pre-management site status.

* #

* #

* # * * # # *# #*

# * #*

* # * # * # * # * # * #

* # * # ** ## * # * # * # * # * # Lake George Outlet June 2010 Site Densities Inset A

* #

* # * # * # Site Status * # * # * # * # * #Bed

Pre_ManageModerate Clear

* #0 2,7002

USGS NED 1/3 arc sec GCS NAD 1983 2009

Scattered

5,400

8,100 Feet

Lycott Environmental Inc. 600 Charlton Rd. Southbridge, MA 01551 Ph. 508-765-0101 Fax 508-765-1352 www.lycott.com


* # * # * # * # * # * #

* # * # ** ## * # * # * # * # * #

* #

* # * # * # * # * # * # * #

* #

# * #** # * # * # * #

* #

* # * # * * #

Site Status Lake George Tiroga-Glenbernie Pre_Manage * # Bed June 2010 * # Moderate Site Densities * # Scattered * # Clear Inset B

0 2,7003


5,400

8,100 Feet



* #

* # * # * * # ** ## * # * # ** ##

* # * # * # * # * # ** ## * #

* # * #

* #

* # * #

* #

* #

* # ** ## * # * # ** ## Lake George Narrows-Tiroga June 2010 Site Densities Inset C Site Status * # * # * # * #Bed


0 2,7004


Scattered

5,400

8,100 Feet



* # * #

* # * # * # * #

* # * #

* # ** ## * # * #

* # * # * # * #

* #

* # ** ## * # * # ** ##

* # * # * # * # * * #* # ## * * * # # ** ##

*# #* *** ### * # * # * # * # * # * * ##

* # * #

*# #*

* #

* #

* #

* # * * # # # *

Site Status Lake George Basin Bay-Narrows Pre_Manage * # Bed June 2010 * # Moderate Site Densities * # Scattered * # Clear Inset D

0 2,7005


5,400

8,100 Feet



* #

* #

* # * * # # # *

* # * # * # * # * # * # * # * # * # * # * # ##* * # * * * ## * # * # * # * # * # * # * # *** ### * # * # * # * # * # * # * # * # * # * # * # * # * # * #

* # * # * # * #

* # * # * #

* # # #* * * # * ## * ** * ## # * # * #

* # * # * #

Lake George LGV-Basin Bay June 2010 Site Densities Inset E

Site Status * # * # * # * #Bed


0 2,7006


Scattered

5,400

8,100 Feet


EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORTTable 1. Lake George 2010 Eurasian watermilfoil sites. If a site remained clear from prior effort, r-clear is coded in the action column. Density categories are assigned prior to management activity. A total of 167 sites were managed by Lycott in 2010 resulting in the removal of 670,821 plants utilizing 1800 person*hours. FUND data are reported in Table 2. 2010 Hand Harvested 8795 42 0 0 93 0 0 2057 94 28 8 0 0 0 36 32 0 0 0 0 0 29 162 696 72 384 14 0 0 390 0 0 0 0 30 4 0 0 37 0 57 2010 Panels OUT 114 2010 Panels IN 2010 Plants removed via BB 184680

Site 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41

Name NWB-Head of Bay Conger's Point SW Conger's Pt NW Sweetbriar Is W. Green Island Sunset Bay Shepards Park West Brook Million Dollar Beach East Brook S. End of Warner Bay LG Outlet NE Mossy Pt. SE Happy Family Is. Finkle Brook Middleworth Bay East end Echo Bay Hague Boat Launch Dunham's Bay Huddle Bay Sheriff's Dock Shadow Bay Lake George YC NWB-W. Tongue Mtn Basin Bay SW Cannon Pt NW Cooper Pt. S. Hearthstone Bay. NE Tea Is. N. Tea Is Bay English Brook Crosbyside S. Plum Pt. Plum & Woods Pt. Bay S of Fan Pt. Dark Bay S. Warner Bay S. Warner Bay-B S. Katskill Bay Bay S. of Red Rock B. Paradise Bay

Basin Middle Middle Middle Middle Middle North South South South South South North North South Middle South Middle North South Middle South Middle South Middle Middle South South South South South South South South South Middle South South South South Middle Middle

Date 16-Aug 21-Jul 21-Jul FUND 21-Jul FUND FUND 9-Aug 26-Jul 19-Jul 15-Jul FUND FUND 15-Jul 21-Jul 20-Jul FUND FUND FUND FUND FUND 19-Aug 26-Jul 27-Jul 20-Jul 26-Jul 21-Jul 19-Jul 19-Jul FUND 19-Jul 19-Jul 19-Jul 19-Jul 22-Jul 15-Jul FUND FUND 15-Jul 9-Jul 9-Jul

2010 Density bed scattered none moderate scattered bed bed moderate scattered scattered scattered bed bed none scattered scattered moderate moderate bed bed bed scattered scattered scattered scattered scattered scattered none none moderate none none none none scattered scattered moderate scattered scattered none scattered

2010 Action cleared cleared r-clear cleared cleared obs reduced cleared cleared cleared cleared obs obs r-clear cleared cleared obs cleared cleared reduced reduced cleared cleared cleared cleared cleared cleared r-clear r-clear cleared r-clear r-clear r-clear r-clear cleared cleared obs obs cleared r-clear cleared

1

168

4

2430

32

51840

7

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORT42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 Bolton Bay T55 Bolton Bay T54 Bolton Bay NE Bridge Tiroga/Black Pt. Leotine/Clay Smith Bay Gull Bay S. Burnt Point Clark Hollow Eichlerville Bay Roger's Rock Beach W. Tongue Mtn Cooks Bay @ HL Indian Bay S. Sawmill Bay S. Green Is. Silver Bay Hondah Cottages Camp Andrew Bay Harbor Is- Moonlight B Marine Village S. Agnes Is. 3 Brothers Is. W. of 3 Brothers Is. N. Sawmill Bay Bluff Head Creek Rock- Dunbar Is. Kitchal Bay S. Trib. W Halfway Is. Hague Brook South Cook's Bay Dark Bay Trib Point N. of Agnes Is. Bell Pt. S. Shelving Rock Pt. Walker Point N. of W. Tongue Mtn. Shore S. of Bear Pt. Bay S of Bear Pt. Butternut Brook Barber Bay Van Warmer Bay Harris Bay Inlet Dunham's Bay Inlet East Shore Crosbyside Crosbyside Crosbyside Middle Middle Middle North Middle North North North North North North Middle North North Middle Middle North Middle Middle North South North Middle Middle Middle North North North North North North North North Middle Middle Middle Middle Middle Middle Middle Middle South South South South South South South 21-Jul 21-Jul 21-Jul 12-Jul 26-Aug 18-Aug 13-Jul 7-Jul 12-Aug 16-Aug 12-Jul 6-Jul 8-Jul 8-Jul 21-Jul 27-Jul 12-Aug 9-Aug 14-Jul 8-Jul 19-Jul 8-Jul 20-Jul 20-Jul 21-Jul 8-Jul 16-Aug 8-Jul 7-Jul 19-Aug 12-Jul 13-Jul 18-Aug 4-Aug 27-Jul 6-Jul 6-Jul 2-Aug 18-Aug 14-Jul 14-Jul 15-Jul 15-Jul 15-Jul 19-Jul 19-Jul 19-Jul 19-Jul scattered scattered none none scattered scattered moderate scattered bed bed none none none scattered none scattered bed scattered scattered scattered none scattered none scattered none none moderate none scattered moderate scattered scattered scattered moderate scattered scattered none moderate scattered none scattered none none none none none none none 3 20 0 0 328 12 1707 20 742 227 0 0 0 12 0 4 252 481 11 20 0 129 0 13 0 0 826 0 4 2205 97 152 137 321 45 1 0 1000 14 0 48 0 0 0 0 0 0 0 cleared cleared r-clear r-clear cleared cleared cleared cleared cleared cleared r-clear r-clear r-clear cleared r-clear cleared reduced cleared cleared cleared r-clear cleared r-clear cleared r-clear r-clear cleared r-clear cleared cleared cleared cleared cleared cleared cleared cleared r-clear cleared cleared r-clear cleared r-clear r-clear r-clear r-clear r-clear r-clear r-clear

1 4

608 6480

13 15

21060 24300

1

270

13

21060

7

11340

10

16200

7

11340

8

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORT90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 S. Tea Is. Culvert Harris Bay E. Side E. of Hens & Chicks Is E. of Refuge Is NW 3 Sirens Is. NWB-Head of Bay Harris Bay- Midbay W. side Clay Is. S. Jenkin's Brook Holman Hill Creek Temple Island Brook N. Green Pt. S. Trib. 5 Mile Mtn. Brk N. N. Meadow Pt. Assembly Pt. West Assembly Pt. NW Assembly Pt. Elizabeth Is. Harris Bay Culvert SW Happy Family Is. Diamond Pt. NWB-NE Walker Pt. Whale Rock Diamond Is. Mooring Post Marina Cape Cod Village Holman Hill Creek N. Glenbernie Blairs Bay Blairs Bay- North E. Side Harris Bay YC North Warner Bay East Shore Still Bay West Flirtation Is. N. Shelving Rock Pt. E. of Sagamore Is. NW Dollar Island SW French Pt. B. N of Commission Pt Camp Sagamore N. Trib. 5 Mile Mtn Brk N.Steere Is. Lamb Shanty Bay Roger's Rock Club St. Sacrement Is. NE Van Warmer Bay Assembly Pt. Pocket B West Dollar Island South South Middle Middle North Middle South Middle North North North North North North South South South South South South South Middle North South South North North North North South South Middle Middle North Middle North Middle Middle Middle North Middle North North North North South South Middle 19-Jul 15-Jul 14-Jul 14-Jul 9-Jul 6-Jul FUND 21-Jul 12-Jul 12-Jul 12-Jul 8-Jul 7-Jul 8-Jul 15-Jul 15-Jul 15-Jul 14-Jul 15-Jul 15-Jul 20-Jul 6-Jul 8-Jul 19-Jul 15-Jul 12-Jul 12-Jul 13-Jul 13-Jul 15-Jul 15-Jul 19-Jul 20-Jul 16-Aug 9-Jul 9-Jul 22-Jul 22-Jul 18-Aug 13-Jul 7-Jul 7-Jul 7-Jul 12-Jul 9-Jul 15-Jul 15-Jul 22-Jul scattered scattered none none none none bed scattered scattered scattered scattered scattered scattered scattered none none none moderate none scattered none none scattered scattered none none scattered scattered scattered scattered scattered none scattered moderate none none none none scattered scattered scattered none scattered scattered none none none scattered 37 2 0 0 0 0 10718 43 2 8 2 12 1 118 0 0 0 934 0 49 0 0 193 5 0 0 123 2 1 7 32 0 72 13 0 0 0 0 479 2 5 0 101 2 0 0 0 5 cleared cleared r-clear r-clear r-clear r-clear reduced cleared cleared cleared cleared cleared cleared cleared r-clear r-clear r-clear cleared r-clear cleared r-clear r-clear cleared cleared r-clear r-clear cleared cleared cleared cleared cleared r-clear cleared cleared r-clear r-clear r-clear r-clear cleared cleared cleared r-clear cleared cleared r-clear r-clear r-clear cleared

3

4860

12

19440

9

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORT138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 Bay N. Fan Pt NE Little Harbor Island NW of 3 Sirens Is. Camp Andrew Bay W. S. of Fox Island S. Bluff Head Creek N. Jenkin's Brook Juniper Is. Blairs Bay-South Gull Island W. side Tea Is. Fish Point E. Rock Bros. Is. Indian Pt. SE Elizabeth Is. Eye of Needle Roger's Slide N. Juniper Is NE Cove Assembly Pt. S. Canoe Islands Georgian Robert Allen Van Buren Bay-S E. Speaker Heck Ch. N. Hazel Island 14 Mile Island N. Leotine Shoal Basin Bay Shoal Harris Bay Shore Acre Clay Island SW SW Green Island Arcady Bay Red Rock Bay S. Delaware Is. N Black Mtn. Point BoltonBay2 Gull Rock Shoal Blair's Bay S.Shore Sandy Bay Arcady Bay Docks Blair's Bay N. Shore1 Blair's Bay N. Shore2 Dunham's Bay-Midbay South Point Diamond I 40 Acre Shoal SW Walker Point Middle North North Middle Middle North North North North North South Middle North North South Middle North North North South South North North South Middle Middle Middle Middle South Middle Middle North Middle North Middle Middle Middle North South North North North South South Middle Middle 19-Aug 22-Jul 9-Jul 14-Jul 9-Jul 18-Aug 12-Jul 12-Jul 13-Jul 13-Jul 19-Jul 20-Jul 13-Jul 7-Jul 29-Jul 17-Aug 17-Aug 12-Jul 15-Jul 20-Jul 19-Jul 13-Jul 7-Jul 19-Jul 9-Jul 20-Aug 3-Aug 20-Jul 28-Jul 20-Jul 19-Aug 19-Aug 18-Aug 17-Aug 5-Aug 9-Aug 17-Aug 18-Aug 9-Aug 19-Aug 17-Aug 12-Jul FUND 26-Jul 20-Aug 20-Aug scattered none none scattered scattered scattered none scattered scattered scattered scattered scattered scattered scattered moderate scattered scattered scattered scattered scattered scattered scattered scattered scattered scattered scattered bed scattered moderate scattered none scattered scattered scattered bed moderate bed scattered scattered scattered scattered scattered bed moderate bed bed Totals: 277 0 0 332 65 9 0 27 98 920 11 86 5 3 680 785 5 1 13 324 4 4 83 65 25 243 2366 79 2616 663 0 15 3 54 2012 908 3319 333 401 9 21 108 0 1696 4370 462 58,359 cleared r-clear r-clear cleared cleared cleared r-clear cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared r-clear cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared cleared obs cleared cleared cleared 3 2835

2

3240

0 3 4860

19.5

31590

4 8 8 19 19.5 15 1 15

6480 12960 12960 30780 31590 24300 270 24300

11 13 3

17820 21060 4860

4 334 51

6480 612,462

10

Figure 2. Map of all known milfoil sites at the conclusion of 2010 management efforts.

* #

* #

* # * * # # *# #*

# * #*

* # * # * # * # * # * #

* # * # ** ## * # * # * # * # * # Lake George Outlet August 2010 Site Densities Inset A

* #

* # * # * # Site Status * * # * # * # * #Bed

Post_managModerate Clear

#

* #0 2,70011


Scattered

5,400

8,100 Feet



* # * # * # * # * # * #

* # * # ** ## * # * # * # * # * #

* #

* # * # * # * # * # * # * #

* #

# * #** # * # * # * #

* #

* # * # * * #

Lake George Tiroga-Glenbernie Post_manag * # Bed August 2010 * # Moderate Site Densities * # Scattered * # Clear Inset B

Site Status

0 2,70012


5,400

8,100 Feet



* #

* # * # * * # ** ## * # * # ** ##

* # * # * # * # * # ** ## * #

* # * #

* #

* # * #

* #

* #

* # ** ## * # * # ** ## Lake George Narrows-Tiroga August 2010 Site Densities Inset C Site Status * # * # * # * #Bed


0 2,70013


Scattered

5,400

8,100 Feet



* # * #

* # * # * # * #

* # * #

* # ** ## * # * #

* # * # * # * #

* #

* # ** ## * # * # ** ##

* # * # * # * # * #* * * # ## * * # # ** ##

*# #* *** ### * # * # * # * # * # * * ##

* # * #

*# #*

* #

* #

* #

* # * * # # # *

Site Status Lake George Basin Bay-Narrows Post_manag * # Bed August 2010 * # Moderate Site Densities * # Scattered * # Clear Inset D

0 2,70014


5,400

8,100 Feet



* #

* #

* # * * # # # *

* # * # * # * # * # * # * # * # * # * # * # ##* * # * * * ## * # * # * # * # * # * # * # *** ### * # * # * # * # * # * # * # * # * # * # * # * # * # * #

* # * # * # * #

* # * # * #

* # # #* * * # * ## * ** * ## # * # * #

* # * # * #

Lake George LGV-Basin Bay August 2010 Site Densities Inset E

Site Status * # * # * # * #Bed


0 2,70015


Scattered

5,400

8,100 Feet


EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORTTable 2. Eurasian Watermilfoil sites scheduled for management by the FUND for Lake George in 2010. Plant counts are based upon estimates from a series of counts of plants in a full bag and extrapolation of the average. A total of 62 sites were treated by the FUND. The results provided are based upon management of individual sites for dense beds or management of several sites while performing swim-over surveys that remove all scattered plants and small beds in a specific geographic area. A total of ~270,000 plants were removed in 2010 as a result of FUND operations utilizing 2400 person*hours. Site(s) 1,95,111,77,22 2,3,4,5,42,43,44,46,164,167,168,173 7,21 8,9,10,86,87,88,89 15,75,66 17 18,71,98,99,115,116,144 19, 180 20 24,35,53,78,79,80,138 30,31,62,90,148,158 41,140,142,162 48,147 85 96 165 Region/Bay Northwest Bolton/Sawmill Caldwell Caldwell Sawmill Echo Hague Dunham's Huddle NorthWest Caldwell Paradise Gull Dunham's Harris Basin Basin Middle Middle South South Middle Middle North South Middle Middle South Middle North South South Middle 2010 Density Scattered Scattered Bed Scattered Scattered Mod/Bed Scattered Bed Bed Scattered Scattered Scattered Scattered Scattered Bed Scattered Total: 2010 Hand Harvested 1000+ 4000+ 140,000 1500+ 4000+ 0 7000+ 30000+ 14000 4000+ 1000+ 1000+ 4000+ 1000+ 20000+ 1500+ 270,000+ 2010 Action Cleared Cleared Reduced Cleared Cleared Obs Cleared Reduced Reduced Cleared Cleared Cleared Cleared Cleared Reduced Cleared

Lycott diver Samantha Edwards hand harvesting at 40-Acre Shoal.

16

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORT Aquatic Plant Management A five-year permit for aquatic plant management in Lake George was issued by the Adirondack Park Agency in 1992 and transferred from NYS DEC to the LGPC in 1994. This permit was most recently renewed in 2006, and allows physical control methods to be applied to manage the growth and spread of Eurasian watermilfoil in Lake George through the summer of 2011. Additionally, in 2009 The Fund for Lake George Inc. contracted with an independent firm to perform hand harvesting at selected sites. This report summarizes all watermilfoil management activities conducted on Lake George in 2010. In the Integrated Aquatic Plant Management Program developed for Lake George, physical plant management techniques form the basis for management activities. Therefore, the general management approach required by the LGPC has been to keep previously cleared sites free of milfoil by conducting hand harvesting where possible (Tables 1 & 2). Once all sites suitable for hand harvesting are cleared, the primary management approach becomes benthic barrier maintenance, installation, and removal (where appropriate). The management strategy for large, dense stands of milfoil in Lake George is relatively long term. Hence, a number of sites may be left without active management (i.e., observed only) in any given year. Preferred physical management approaches are based upon density of milfoil growth and logistics (i.e., time constraints, location of sites and availability of management tools such as barrier panels). Scattered sites and some moderately dense sites are managed through hand harvesting depending upon other site conditions. Large, dense beds are managed with benthic barrier or as of 2009 through large-scale hand harvesting by Lycott and the FUND. Of the 183 known milfoil sites, 181 have been managed for milfoil in one or more years since the start of aquatic plant management efforts. Of these, 117 were cleared of milfoil in 2010. An additional 54 sites remained clear of milfoil from prior efforts. Thus, at the close of the 2010 effort, 171 of the 183 sites were clear of milfoil. Cleared, as used in this context, indicates removal of all visible milfoil plants, including roots. As of 2005, cleared also includes sites which have benthic barrier in place, but which are devoid of milfoil. Because sites can be re-colonized by fragments generated at nearby sites and/or from fragments unintentionally left behind, cleared sites may experience re-growth of some milfoil between management efforts. Nine sites remain which require a more intensive management strategy than the traditional hand harvesting approach. Two sites in Lake George currently have stands of milfoil toward which no management activity has been directed.

17

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORTTable 3. Number of reported milfoil sites and their status at the conclusion of each survey year. Data for years 1985-2001 are from Eichler & Boylen 2001. Except for the Total column, data in this table are not necessarily inclusive of all sites; there is a hidden category of managed sites. Sites which are actively being managed with benthic barrier but which still have stands of milfoil are considered managed sites. New sites are accounted for in the appropriate category and are listed here to track number of new sites/year. In previous annual activity reports (2004 and prior) sites were considered managed if benthic barrier remained even if the site was devoid of milfoil. Since 2005, all sites devoid of milfoil are listed as cleared even when benthic barrier remains in place. Density of Milfoil Growth Year 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 Total # of Milfoil Sites 3 22 43 55 66 76 91 97 106 N/A 111 118 123 127 134 136 141 144 146 148 149 157 160 171 179 183 Bed 3 9 8 8 12 13 11 16 21 N/A 26 25 28 31 34 28 24 23 22 20 18 17 14 16 9 9 Moderate 0 0 0 0 6 8 7 4 13 N/A 13 11 11 7 7 8 11 7 6 8 10 9 8 6 6 2 Scattered 0 13 29 35 23 19 27 40 10 N/A 5 9 13 6 4 3 4 4 3 2 2 0 6 9 0 1 New 3 19 21 12 11 10 15 6 9 N/A 1 7 5 4 7 2 5 3 2 2 1 8 3 11 8 4 Status Clear 0 0 6 12 25 36 46 37 62 N/A 67 73 72 83 91 94 103 110 114 112 115 127 132 140 164 171

Hand Harvesting Lycott divers cleared 167 sites via hand harvesting or confirmed that sites had remained clear. In doing so, 58,359 plants were removed. The number of hand-harvested plants were determined by a tally of individual plants kept by divers as each site was cleared. FUND divers removed ~270,000 plants by hand harvesting. However, their management and plant count methodology differs from that of Lycott. Lycott efforts typically are centered around documented sites while FUND divers employ the parallel search pattern to survey/manage shoreline and bay areas (encompassing documented sites in the process). The FUND effort in 2010 cleared an additional four documented sites as well as

18

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORT numerous plants between sites. Thus, a combined total of 171 sites were clear of milfoil at the close of milfoil management operations by all groups.Table 4. Recent hand-harvest effort. 1999-2001 data are from DFWI, 2002-2010 data are from Lycott. In previous annual activity reports (2004 and prior) sites were listed as managed if benthic barrier remained even if the site was devoid of milfoil. Beginning in 2005, all sites devoid of milfoil are listed as cleared even if benthic barrier remains in place.Year 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 20101

Number of Sites 65/26 91 46/48 94 50/55 105 68/42 115 64/50 116 58/54 119 72/43 122 73/54 131 80/52 139 93/47 153 109/48 168 113/54 167

1

Number of Plants Hand Harvested 5,733 4,065 5,074 11,605 17,438 9,387 7,073 13,409 19,753 14,690 23,534 58,359

Total PersonHours 193 211 352 491 546 501 480 390 422 450 480 1,040

Average PersonHours/ Hand-Harvest Site 3.1 4.4 3.4 4.2 4.6 4.2 3.9 4.0 3.1 2.9 2.9 6.2

Top numbers in cells are sites cleared/sites that remained clear (from prior years effort). Bottom number in cell is total number of sites worked (i.e., hand harvesting and/or benthic barrier installation/maintenance)

Figure 3. 2010 Distribution of Lycott hand-harvesting effort. Graph represents 1,040 total personhours.

Set-Up; 14% Travel; 16% Hand Harvest; 70%

19

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORT Benthic Barrier References to the relocation or installation of benthic barrier panels in Lake George 2001-2006 refers exclusively to Palco pond liners. These panels are a negativelybuoyant polyvinyl chloride (pvc) material and are each cut to 7x 50 (350 ft2). Beginning in 2007, generic 20-mil pvc pond liners were used. These panels are also a negativelybuoyant pvc material, however they are slightly larger at 7.5 x 50 (375 ft2). Both types of panel require overlap with adjacent panels. Thus, the actual coverage once installed is slightly less than the product of the number of panels at each site by the total square feet of each panel. Benthic barrier installations in Lake George over 20+ years have shown very high rates of plant removal and very low rates of milfoil recruitment following panel extractions (Miller & King, 2010). Eichler et. al. (1995) reported as high as 75% of their study plots had milfoil present one year post-barrier extractions, however their study was conducted at a time when numerous, larger, source populations of milfoil still existed in close proximity of their study plots. This is no longer the case as the vast majority of those beds were removed through ongoing barrier installations (reported herein). Thus management of large milfoil beds with barrier in Lake George has been very effective in local population control as well as in a reduction in the re-establishment of managed sites from nearby unmanaged sites (Miller & King, 2010). Sites managed with benthic barrier in previous years were inspected and maintenance was performed where required. A total of 69 sites in Lake George which were formerly dense stands of milfoil have been managed with benthic barrier; 61 are now clear of milfoil, two are controlled but not yet completely devoid of milfoil, and six have milfoil growth which is not currently controlled (Table 1 & Appendix D). Routine benthic barrier inspections were conducted at all barrier locations. Panels were inspected, cleaned where possible and repaired as needed. Maintenance included repositioning of panels to close gaps, venting of trapped gases, as well as moving and installing additional weight bars as necessary. In addition to routine maintenance, six sites had barrier installed and 25 sites had barrier panels removed in 2010 (Table 1). Large benthic-barrier installations occur exclusively at sites where milfoil stands are monotypic and clearly exhibiting invasive growth. Based upon density estimates and bed size, plant counts can be estimated where benthic barrier is installed. Density estimates for these sites in Lake George show 4.8-5.0 plants per square foot (King, unpublished data). Taking site-specific density data, accounting for panel overlap and buffer coverage beyond the margin of the milfoil bed, accurate plant-removal estimates can be obtained. Following this rationale, Lycott removed 612,462 plants with benthic barrier operations from 2009-2010 (panels remain in place at least one year).

20

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORTTable 5. Lycott data for benthic barrier installation and removal by year. Panels in years 2004-2005 were 350 ft each. 2 Panels in 2007 and later are 375 ft each. Panels Average Square Feet Average (removed)(installed) PersonHours (removed)(installed) sf/ # Sites Year PersonHours (total) (total) PersonHour Worked per Panel (6)(135) (1,800)(42,000) 2004 560 141 3.97 43,800 78.2 8 (102)(135) (31,000)(42,000) 2005 510 237 2.15 73,000 143.1 13 (3)(317.5) (900)(96,000) 2006 694 320.5 2.17 96,900 139.6 16 (0)(487.25) (0)(170,537.5) 2007 1,514 487.25 3.11 170,537.5 112.6 15 (0)(331) (0)(115,850) 2008 1,310 331 3.96 115,850 88.44 21 (242)(210.5) (90,750)(78,937.5) 2009 1,310 452.5 2.89 169,687.5 129.53 33 (334)(51) (125,250)(19,125) 2010 760 385 1.97 144,375 189.97 31 Figure 4. Distribution of Lycott effort for benthic barrier management conducted in 2010. Graph represents 760 total personhours.2

Travel; 16%

Set-Up; 15% Benthic Barrier; 69%

General Conclusions Of the183 known watermilfoil sites, a total of 171 (93%) were clear at the conclusion of year 2010 management efforts. Approximately 32% of the 171 cleared sites remained so for one or more years. Furthermore, 54% of these 171 cleared sites were cleared with modest hand harvesting effort (i.e., 0-500 plants). Lycott removed a total of 58,359 plants by hand harvesting and an additional 612,462 plants through management with benthic barrier. FUND estimated a removal of ~270,000 plants through their hand harvesting efforts. Lycott total effort was 1800 person*hours in 2010; FUND total effort was 2400 person*hours. In addition to plant removal, FUND divers surveyed many acres of shoreline insuring that any undocumented incipient populations were found and removed from their target areas. Together, the two approaches (Lycott & FUND) have increased

21

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORT the pace at which the unmanaged Eurasian watermilfoil populations are reduced to controllable levels. In 2010, a total of just over 0.4 acres (51 panels) of benthic barrier were installed across six sites (Table 1). These six sites also produced 3,708 (6%) of the total plants hand harvested by Lycott in 2010. Beginning in 2009, a concerted effort was made for large-scale extraction of in-lake barrier panels. In 2010, 2.9 acres (334.5 panels) were removed from 25 sites. In total, barrier operations led to a net decrease of in-lake panels by 2.5 acres. Since the beginning of barrier operations 19.1 acres of panel have been installed. As of August 2010, only 6.8 acres of panel remain in place across 29 sites (Appendix D). There were 18 bed sites and 17 moderate sites in Lake George when management efforts began in June 2010 (Table 1, Figure 1) for a total of 35 sites needing significant effort. Nine of the 18 bed sites were cleared in 2010. Fifteen of the 17 moderate sites were cleared, and two were not managed. Ninety-three of the 94 scattered sites were cleared in 2010. Therefore, nine bed sites, two moderate sites, and a single scattered site remained in Lake George (Figure 2) at the close of 2010 operations. These will require future management effort in addition to the routine annual work at controlled sites. Figure 5 shows historical site density at the onset of management operations by site (i.e., this shows the maximum density any given site has obtained prior to management efforts dating back to 1986). Comparisons of figures 1 or 2 with figure 5 readily shows the value that the integrated approach to milfoil management has had in Lake George over the past 20+ years.

Paradise Bay, August 2010.

22

Figure 5. Historical site densities at the onset of management effort by site.

* #

* #

* # * * # # *# #*

# * #*

* # * # * # * # * # * #

* # * # ** ## * # * # * # * # * # Lake George Outlet Historical Site Densities Inset A

* #

* # * # * #

Legend # *

Site Status * # Bed * # Moderate * # Scattered

* #0 2,50023


5,000

7,500 Feet



* # * # * # * # * # * #

* # * # ** ## * # * # * # * # * #

* #

* # * # * # * # * # * # * #

* #

# * #** # * # * # * #

* #

* # * # *

* # Lake George Legend Tiroga-Glenbernie Site Status * # Bed Historical Site Densities * # Moderate * # Scattered Inset B

0 2,50024


5,000

7,500 Feet



* #

* # * # * * # ** ## * # * # ** ##

* # * # * # * # * # ** ## * #

* # * #

* #

* # * #

* #

* #

* # ** ## * # * # ** ## Lake George Narrows-Tiroga Historical Site Densities Inset C

Legend


0 2,50025


5,000

7,500 Feet



* # * #

* # * # * # * #

* # * #

* # ** ## * # * #

* # * # * # * #

* #

* # ** ## * # * # ** ##

* # * # * # * # * * #* # ## * * * # # ** ##

*# #* * *## #** # * * ## * * # * * ##

* # * #

*# #*

* #

* #

* #

* # * * # # # *

Lake George Legend Basin Bay-Narrows Site Status * # Bed Historical Site Densities * # Moderate * # Scattered Inset D

0 2,50026


5,000

7,500 Feet



* #

* #

* # * * # # # *

* # * # * # * # * # * # * # * # * # * # * # ##* * # * * * ## * # * # * # * # * # * # * # *** ### * # * # * # * # * # * # * # * # * # * # * # * # * # * #

* # * # * # * #

* # * # * #

* # # #* * * # * ## * ** * ## # * # * #

* # * # * #

Lake George LGV-Basin Bay Historical Site Densities Inset E

Legend


0 2,50027


5,000

7,500 Feet


EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORT References Boylen, C.W., L.W. Eichler, and J.W. Sutherland, 1996. Physical Control of Eurasian Watermilfoil in an Oligotrophic Lake. Hydrobiologia. 340(1-3): 213-218. Eichler, L. W, and C. W. Boylen. 2001. Eurasian watermilfoil management in Lake George, New York for 2001. FWI Report 2001-5. Rensselaer Fresh Water Institute, Troy, NY. Eichler, L. W., R. T. Bombard, J. W. Sutherland and C. W. Boylen. 1993. Suction harvesting of Eurasian watermilfoil and its effect on native plant communities. J. Aquat. Plant Manage. 31:144-148. Eichler, L. W., R. T. Bombard, J. W. Sutherland and C. W. Boylen. 1995. Recolonization of the Littoral Zone by Macrophytes following the Removal of Benthic Barrier Material. J. Aquatic Plant Manage. 33: 51-54. King, R. W, and L. Lyman. 2009. Eurasian watermilfoil management in Lake George, New York, 2006. Lycott Technical Report LG2009. Lycott Environmental Inc. Southbridge, MA. USA Madsen, J.D., L.W. Eichler and C. W. Boylen. 1988. Vegetative spread of Eurasian Watermilfoil in Lake George, New York. J. Aquat. Plant Manage. 26:47-50. Madsen, J. D., J. W. Sutherland, and L. W. Eichler. 1989. Hand harvesting Eurasian Watermilfoil in Lake George. FWI Report 89-8. Rensselaer Fresh Water Institute, Troy, NY. Miller, E. M., and R.W. King. 2010. Comparison of hand harvest and benthic barrier methods for control and spread of Eurasian Watermilfoil in Lake George, 1987-2010. Lycott Technical Report. Clark University Internship by EXM, 2010. Lycott Environmental Inc.

28

EURASIAN WATERMILFOIL MANAGEMENT IN LAKE GEORGE 2010 PROGRAM REPORT

APPENDIX ADescriptions of Eurasian Watermilfoil Sites Criteria used for site designations follow Eichler & Boylen (2001). Briefly, sites are designated as beds when >50 percent of the total macrophyte community cover was milfoil, moderate when milfoil was 10 percent cover, and scattered when

Final Milfoil Report

Documents

Transcript of Final Milfoil Report