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J. Maassen. CINMS. California’s Gold: Using ecological and collaborative research to inform fisheries management strategies for the red sea urchin, Strongylocentrotus franciscanus Sarah Teck, Sarah Rathbone, Nick Shears, Rebecca Toseland, Scott Hamilton, Jenn Caselle and Steve Gaines.
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J. Maassen CINMS California’s Gold: Using ecological and collaborative research to inform fisheries management strategies for the red sea urchin, Strongylocentrotus franciscanusSarah Teck, Sarah Rathbone, Nick Shears, Rebecca Toseland, Scott Hamilton, Jenn Caselle and Steve Gaines Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, CAteck@lifesci.ucsb.edu
California’s Gold incabrain.com San Francisco Santa Barbara ~34°N ~120°W Santa Barbara San Miguel Santa Cruz Santa Rosa Channel Islands Anacapa 25 km
California’s Gold (5th largest fishery) ~66% is harvested from here incabrain.com • ~52% is landed here Santa Barbara San Miguel Santa Cruz Santa Rosa Anacapa 25 km
Sea Urchin Fishery in California Data: CDF&G
Sea Urchin Fishery in California Data: CDF&G
89 mm N CA; seasonal limit # days per week 76 min size limit Moratorium on permits 83 mm S CA; seasonal limit # days per week El Niño ↓ Japanese economy ↑ market competition El Niño El Niño Data: CDF&G
89 mm N CA; seasonal limit # days per week 76 min size limit Moratorium on permits 83 mm S CA; seasonal limit # days per week El Niño ↓ Japanese economy ↑ market competition El Niño El Niño Data: CDF&G
Motivation • Status of the stock unknown • Collect baseline information — precautionary approach • Integrate ecological, economic, and fisheries data to improve management • Can yields or profits increase with different management?
Quality, not just quantity and size • fished species: • population size • individual size • urchins: • gonad quality • time (seasons) • space (islands) Objective: temporal and spatial variability of gonad quality fisheries management
Steep temperature gradient (Blanchette et al 2007)
Steep biotic gradient S. purpuratus • Sites deforested by purple urchins~33-87% of the time (Shears in prep, National Park Service-Kelp Forest Monitoring data 1985-2007) 2007 purple abundance COMPETITOR Macrocystis pyrifera RESOURCE by Scott Gietler
>400 boats surveyed Dec 2008-present Port sampling location, effort, landings, GSI, price… Objective: temporal and spatial variability of gonad quality fisheries management
Gonad quality (size, texture and color) P=0.0045 R2=0.71
Gonad quality is highly variable boats=196 urchins=2190
Gonad quality is predicable mean GSI/month
no diff. AMONG ISLANDS: • (1) mean (2) phase shift (3) period
Amplitude of SCI differs P=0.0250 * P=0.0016 **
Why does amplitude vary spatially? • Gonad quality is governed by physiological response to environment and ecology • Temperature • higher metabolism in warmer water faster somatic growth? • Food quality and availability • less kelp in warmer water and with competitors (purples) less allocation to reproduction?
Fishery implications • Optimal profits to harvest • SMI/SRI before reproduce (high productivity here) • SCI after reproduce (lower productivity here)
Next steps… • Examine fishermen behavior—are they fishing optimally? (landing receipt data) • Bioeconomic model—How will urchin populations and fishery profits respond to various management regimes? • ex: Seasonal quota (TAC) or effort ; property rights (TURFs) • Optimal harvest strategy over time and space • Feasible harvest strategy within this fishery
THANKS TO… • Commercial Fishermen of Santa Barbara: urchin divers, H. Liquornik, S. Mutz • Lab assistants: M. Adams, A. Alger, G. Alongi, K. Asanion, M. Bogeberg, E. Casas, D. Cooper, M. Hunt, S. Meinhold, W. Meinhold, A. Poppenwimer, J. Roh, R. Shen, T. Shultz, A. Stroud, K. Treiberg, O. Turnross, A. Wong, • PISCO dive team: K. Davis, A. Parsons-Field, E. Nickisch, J. Benson, P. Carlson, L. Hesla, E. Hessell, C. Lantz, JA Macfarlan, C. Pierre, D. Salazar, B. Selden, A. Soccodato, N. Spindel, S. Windell, • EEMB/Bren: Gaines lab, Lenihan lab • J. Lorda, L. Pecquerie, H. Salgado, B. Broitman
Management challenge gonad quality time peak quality trough quality
Harvesting in different areas Reef 1 gonad quality Reef 2 time
Harvesting peaks in different areas Reef 1 Reef 2 gonad quality time
Percent gonad is higher in the west 32 sites summer 2009 27 sites summer 2010 a a 9.5% 9.5% Santa Barbara c b 6.7% 5.6% Santa Cruz Anacapa San Miguel Santa Rosa
Purple urchin abundance 2007 Red urchin landings 1985-2005 Shears in prep, NPS—KFM, CDFG data
Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO) ecosystem research and monitoring (fish and benthic subtidal sampling) 32 sites summer 2009 27 sites summer 2010
III. Ecology What drives variability in red urchin populations over time and space? Santa Barbara • Regression model to predict GSI • Temperature, abiotic factors • Reserve versus fished • Community data San Miguel Santa Cruz Santa Rosa Anacapa
Long-term (1985-2007) E Santa Cruz and Anacapa kelp Density (m-2) purple urchins Density (m-2) red urchins Biomass (gm-2) Shears in prep, NPS—KFM data
Long-term (1985-2007) E Santa Cruz and Anacapa kelp Density (m-2) purple urchins Density (m-2) red urchins Biomass (gm-2) Shears in prep, NPS—KFM data
Long-term (1985-2007) E Santa Cruz and Anacapa kelp Density (m-2) • Red urchins have persistently higher biomass inside of the reserves. • Reproductive output is ~4 times higher in kelp forests versus urchin barrens purple urchins Density (m-2) red urchins Biomass (gm-2) Shears in prep, NPS—KFM data
manipulate ecology of a managed area to increase profits • Purple urchin removals in historical red urchin fishing grounds? • kelp restoration
New strategy for fishing sea urchins • To take advantage of the high quality roe at the time when and locations where it is available, fish more in winter and in places where roe is of the highest quality. • to increase profits to urchin fishermen • to benefit sea urchin populations
GSI increases during regrowth west central east spawning gonadal regrowth
How do urchins and fishery profits respond to various management regimes? • IV. Management
Assess management strategies • Seasonal quota (TAC) • Individual quotas • Minimum size limits • Maximum size limits • Limited entry • Area closures • TURFs • Combination of various strategies
Quality varies seasonally % gonad of whole body weight { } west central east
Reserves may affect gonad quality (Behrens & Lafferty 2004, Lafferty & Behrens 2005)