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Fishermen & scientists collaborate to monitor lobster nurseries in New England & Atlantic Canada . Richard A. Wahle University of Maine. Overview. The vision The tool kit A Case study: the Rhode Island collapse Implications & Future. Suction Sampling. Passive Collectors. NEAq.
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Fishermen & scientists collaborate to monitor lobster nurseries in New England & Atlantic Canada Richard A. Wahle University of Maine
Overview • The vision • The tool kit • A Case study: the Rhode Island collapse • Implications & Future
Suction Sampling Passive Collectors NEAq The Vision: Linking Life Stages/ Probing Processes Pelagic Pre-settlement Processes Postlarvae Larvae Larval Settlement Egg Production Inshore Trawl Surveys Juveniles Adults Benthic Post-settlement Processes
Suction sampler Passive Collector
Burdett-Coutts/MUN NL Fishermen Lawton/ DFO Rochette/ UNB Comeau/ DFO PEI Fishermen Tremblay/ DFO Fishermen & Scientists RS Wilson/ ME DMR Carloni/ NH F&G Glenn/ MA DMF Gibson/ RI DEM
Geographic Patterns 2008 Older juv YoY
Geographic Patterns 2008 Suction Samples 2008 Collectors 2008 Gulf of St. Lawrence QC NL Gulf of St. Lawrence QC NL PEI NB PEI NB ME ME NS NS NH Gulf of Maine NH Gulf of Maine MA RI MA RI Older juv YoY
Contrasting thermal regimes Bay of Fundy BOF Gulf of Maine 0 0 0 50 50 50 100 100 100 GOM So. New England Temperature (°C) Depth (m) SNE Jul Jan Jun Feb Apr Oct Sep Mar Dec Aug Nov May
YoY Temperature Bay of Fundy Gulf of Maine Southern New England
Suction Sampling Time Series Beaver Hbr, NB Jonesport, ME Mt. Desert, ME Pen. Bay, ME Mid-coast, ME Casco Bay, ME York, ME Beverly, MA Cape Cod Bay, MA Buzzards Bay, MA Rhode Island
Photo ME DMR Rhode Island: Predicting Pre-recruits from Settlement
njscuba.com Remaining polysac matrix Bacteria Alistair Dove Protists Healthy chitin Roxanna Smolowitz Shell Disease
Rhode Island’s time line: landings, pre-recruits and shell disease Landings Pre-recruits Disease
Rhode Island: Joint effects of settlement & disease on pre-recruits (Wahle et al. 2009)
Declining NAO Index 2010
Joint effects of Spawners & NAO on Settlement R= recruitment (settlers) S= spawning stock C= auxiliary variable (NAO Index) α= max rate of recruitment β= coeff compensatory mortality γ= coeff mortality due to auxiliary factor R=α S e-βS-γC
Recap • ALSI collaborative widens scale of monitoring • RI case study – Closing the life cycle • Prior to 1996, settlement predicts pre-recruits. A first for clawed lobster! • Since 1996, joint effects of settlement + disease model (Wahle et al. 2009). A first for marine invertebrates! • Spawners + NAO predict settlement (Gibson in prep.). A first for clawed lobster!
Implications • We’re part drivers, part passengers on this train • Dynamics more local than we thought. • What’s next? • Evaluate predictive power by region • Formalize the ALSI collaborative • Dedicated Web portal: data submission & reporting.
Grad students - Charlene, Mahima Interns Charlene Bergeron (Tech., Grad student) Noah Oppenheim (NSF REU) Katherine Thompson (Intern) Lee Reeve (Intern) MahimaJaini (Grad student)
Rhode Island: Settlement predicts Pre-recruits 3 years later 1990 -1996 1997-2002 (Wahle et al. 2009)
Photo ME DMR Nearshore Trawl Surveys
Relative Natural Mortality = -ln(prerecruits/settlers) Pre-disease Disease
Is the Gulf of Maine Next? 2003-2010 2002 Fall 2000 Spring 2000 R. Glenn, MA DMF Fall 1997 1998 1999
Warming Temperatures? From Sea Surface Temperatures, Woods Hole, MA 1945-2004 (Glenn & Pugh 2006)
Settlement & Crowding Predation Pressure Disease Recap: Emerging Patterns in Post-settlement Processes
1993 Lawton, DFO, Beaver Hbr 2 Rhode Is. 6 1992- 1994 NL QC NB ME Mid-coast 8 NH MA RI
The American Lobster Settlement Index: Fishermen and scientists collaborate to monitor lobster nurseries in New England & Atlantic Canada Richard A. WahleUniversity of Maine
1 yr olds Settlers Rhode Island: Following cohorts through time (from Wahle et al. 2004)
Magdelan Islands Hudon (1987) Rhode Island Midcoast Maine 1987- 1991 NL QC NB ME NH MA RI
The American Lobster Settlement Index:Fishermen & scientists collaborate to monitor lobster nurseries in New England & Atlantic Canada Richard A. Wahle, Charlene Bergeron, University of Maine, USA John Tremblay, Dept Fisheries & Oceans, Halifax, Canada Carl Wilson, Maine Dept Marine Resources, USA Michel Comeau, Dept Fisheries & Oceans, Moncton, Canada RémyRochette, University of New Brunswick, St. John, Canada Peter Lawton, Dept Fisheries & Oceans, St. Andrews, Canada Victoria Burdett-Coutts, Memorial University, St. Johns, Canada Robert Glenn, Massachusetts Div. Marine Fisheries, USA Mark Gibson, Rhode Island Dept Fish & Wildlife, USA
Bay of Fundy Gulf of Maine So. New England