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COMPARISON OF DIFFERENT DEPLOYMENT STRATEGIES FOR BAY SCALLOP SPAWNER SANCTUARIES IN NEW YORK Stephen T. Tettelbach, Dennis Bonal, Andrew Weinstock, C.W. Post Campus of Long Island University, Brookville, NY 11548 Debra Barnes, NY State Dept. of Environmental Conservation, East Setauket, NY 11733 Gregg Rivara, Cornell Cooperative Extension of Suffolk County, Southold, NY 11901 Chelsea Fitzsimons-Diaz, Roger Williams University, Bristol, RI 02809 John Carroll, Stony Brook University, Southampton, NY 11968 ---PAGE BREAK--- Funded through the State Wildlife Grant Program - New York Collaborators: NYS Dept. of Environmental Conservation: Debra Barnes, Josh Thiel, M. Chase Cammarota Cornell Cooperative Extension of Suffolk County: Gregg Rivara, R.Michael Patricio Town of East Hampton Shellfish Hatchery: John Aldred, Frank Quevedo, Jennifer Gaites, Barley Dunne The Nature Conservancy: Wayne Grothe, Adam Starke, Joe Zipparo Long Island University: authors, plus Richard Ames, Shalini Gopie, Alex Mattis, Lindsay Moore, Kate Newman, Jennifer Rice; Ashton Schardt, Ian Simmers ---PAGE BREAK--- New York Bay Scallop Landings - Commercial - 0 100 200 300 400 500 600 [PHONE REDACTED] 1970 1974 1978 1982 1986 1990 1994 1998 2002 # Pounds of Meats (1000's) ---PAGE BREAK--- New York Bay Scallop Planting Methods: Overwintering and/or for Spawner Sanctuaries ---PAGE BREAK--- Study Objectives: • Evaluate Use of Suspended ADPI Bags for Bay Scallop Spawner Sanctuaries • Compare ADPI Bag System to High Density Free-Plantings ---PAGE BREAK--- NWH = NW Harbor ---PAGE BREAK--- 25 m 25 m 25 m 25 m 25 m Free-Planted Sectors ADPI Arrays SI EH SI EH Ave. Initial Planting Density = Initial Planting Density = 95-132/ m2 117/234/468/ m2 ~235,000-277,000 Planted/Year 12,600 Planted/Year 2005: Scallops Planted 30 Mar – 1 Apr Initial Mean Size = 38-40 mm 2006: Scallops Planted 3 – 7 Apr Initial Mean Size = 33-35 mm 36 Arrays (3 bags ea): SI or EH 15 mm mesh 50, 100, or 200 per tier (bag) ---PAGE BREAK--- Design of ADPI Bag Arrays 2006 ---PAGE BREAK--- Overall Survival: ADPI Bags vs Free-Plants Overall % Survival 0 10 20 30 40 50 60 70 (mid-August: ~4.5 months after planting) bags free bags free 2005 2006 ---PAGE BREAK--- Density of Free-Planted Bay Scallops Scallop Density m) 0 50 100 150 200 250 300 Sector 1 (SI) Sector 2 (EH) Sector 3 (SI) Sector 4 (EH) April May June July Aug Sept Oct (Mean 1 SE) 2005 ---PAGE BREAK--- Density of Free-Planted Bay Scallops Scallop Density m) 0 50 100 150 200 250 300 350 Sector 1 (SI) Sector 2 (EH) Sector 3 (SI) Sector 4 (EH) April May June July Aug Sept Oct (Mean 1 SE) 2006 ---PAGE BREAK--- SI EH SI EH 50 100 200 50 [PHONE REDACTED] 2006 2005 2006 Scallop Source # Scallops Stocked/Bag (Mid-August: ~ 4.5 Months After Planting) ---PAGE BREAK--- 0 10 20 30 40 Scallop Shell Growth (~6.5 months after planting) Median Shell Growth (mm) EH SI EH SI EH SI EH SI bags free-plants bags free-plants 2005 2006 A A B B B B BC C K-W 1-way ANOVA (p<.001) / Dunn’s Test (p<.05) ---PAGE BREAK--- October 2006 Free-plant Array ---PAGE BREAK--- Wet Wt of Fouling Organisms 0 1 2 3 4 5 Fouling Organisms: August ’05, ‘06 (Mean + 1 SE) Free-Plants ADPI bags 2005 2006 2005 2006 A A B B K-W 1-way ANOVA (p<.001) / Dunn’s Test (p<.05) ---PAGE BREAK--- 2005 ---PAGE BREAK--- ---PAGE BREAK--- Temporal Spawning Patterns 2005 Gonad Index 0 10 20 30 40 50 SI bags EH bags SI free plants EH free plants April May June July Aug Sept Oct Nov (Mean 1 SE) ---PAGE BREAK--- Temporal Spawning Patterns Gonad Index 0 10 20 30 40 50 SI bags EH bags SI free plants EH free plants (Mean 1 SE) April May June July Aug Sept Oct Nov 2006 ---PAGE BREAK--- 7 June 2005 ---PAGE BREAK--- SUMMARY • High density free-plants: 59% mean survival to 1st spawning, 2+ mos after planting (2005); 10% mean survival to 1st spawning, 2 mos after planting (2006) More rapid decline in in 2006: possibly due to lack of eelgrass, smaller initial size, and/or higher initial density • Scallop survival usually better in ADPI bags compared to free-plants; less tilting of ADPI bags in 2006 reflected in higher survival vs 2005 • Scallop shell growth: less in ADPI bags vs free-plants • Bio-fouling levels much higher on scallops in ADPI bags vs free-plants • Spawning of scallops in ADPI bags and on bottom peaked at ~ same time in respective years, at similar levels of reproductive investment (GI)