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California’s Gold: Ensuring a profitable and sustainable sea urchin fishery Sarah Teck 14 April 2011 CINMS J. Maassen.

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Presentation on theme: "California’s Gold: Ensuring a profitable and sustainable sea urchin fishery Sarah Teck 14 April 2011 CINMS J. Maassen."— Presentation transcript:

1 California’s Gold: Ensuring a profitable and sustainable sea urchin fishery Sarah Teck 14 April 2011 CINMS J. Maassen

2 Santa Barbara San Miguel Santa Rosa Anacapa Santa Cruz California’s Gold (5 th largest fishery) ~66% is harvested from here incabrain.com ~52% is landed here

3 Red urchin fishery landings have dropped Data: CDF&G ~ 52  ~11 million lbs

4 Red urchin ex-vessel prices have dropped ~$34  ~$6 million ~ 52  ~11 million lbs Data: CDF&G

5 Red urchin effort has changed over time Data: CDF&G

6 83 mm S CA; seasonal limit # days per week 76 min size limit Moratorium on permits 89 mm N CA; seasonal limit # days per week El Niño ↓ Japanese economy ↑ market competition

7 (Kalvass and Hendrix 1997)

8 Quality not only quantity and size as with all fished species, need to consider: population size individual size with urchins, also need to consider gonad quality, and how it varies across: seasons islands (or space)

9 P=0.0045 R 2 =0.71 Value increases with gonad quality

10 % gonad of whole body weight Quality varies seasonally west central east

11 % gonad of whole body weight Quality varies seasonally west central east {

12 % gonad of whole body weight Quality varies seasonally west central east { }

13 % gonad of whole body weight Quality varies seasonally west central east { }

14 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

15 California’s Gold: Investigating the effect of management strategies on the red sea urchin fishery and population Sarah Teck, Sarah Rathbone, Sarah Valencia, Nick Shears, Scott Hamilton, Jenn Caselle, Steve Gaines Photo: CINMS Photo: J. Maassen

16 Santa Barbara San Miguel Santa Rosa Anacapa Santa Cruz California’s Gold (5 th largest fishery) ~66% is harvested from here www.incabrain.com ~52% is landed here

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18 Gonad quality not just size with fished species need to wait for individuals and population growth with urchins also need to wait for seasonal gonad quality gonad weight / whole body weight OR gonad: somatic index (GSI) need to understand more detailed ecological information on temporal and spatial variability of gonad quality  fisheries management

19 Outline III. Ecology What drives variability in red urchin populations over time and space? How do urchins and fishery profits respond to various management regimes? IV. Management How does gonad quality explain behavior of fishermen? II. Fishing behavior What drives variability in gonad quality (and price) over time? I.Fished quality

20 What drives variability in gonad quality (and price) over time? I.Fished quality Fishermen as optimal foragers multiple linear regression – seasonality – space – ecological drivers (kelp etc.) – environmental predictors – time or date? – water temp? – day length?

21 Santa Barbara Port sampling 400 boats surveyed 200 boats GSI Dec 2008-present location, effort, landings, GSI, price…

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23 Port sampling fished sites

24 P=0.0045 R 2 =0.71 price is highly correlated with GSI

25 GSI is highly variable

26 variation partially explained by space west central east

27 GSI varies seasonally west central east

28 GSI decreases during spawning west central east spawning

29 GSI increases during regrowth west central east spawninggonadal regrowth

30 Outline How does gonad quality explain behavior of fishermen? II. Fishing behavior What drives variability in gonad quality (and price) over time? I.Fished quality

31 How does gonad quality explain behavior of fishermen? II. Fishing behavior Model to predict fishing behavior (typically density is important, but in this fishery it is quality) areas with high GSI will have high effort and over time the GSI will be driven down by high effort—then fishermen move…

32 Outline III. Ecology What drives variability in red urchin populations over time and space? How does gonad quality explain behavior of fishermen? II. Fishing behavior What drives variability in gonad quality (and price) over time? I.Fished quality

33 Santa Barbara San Miguel Santa Rosa Anacapa Santa Cruz III. Ecology What drives variability in red urchin populations over time and space? Regression model to predict GSI Temperature, abiotic factors Reserve versus fished Community data

34 Steep temperature gradient (Blanchette et al 2007) Regression model to predict GSI Temperature, abiotic factors Reserve versus fished Community data

35 (Behrens & Lafferty 2004, Lafferty & Behrens 2005) Regression model to predict GSI Temperature, abiotic factors Reserve versus fished Community data Reserves may affect GSI

36 Purple sea urchin Strongylocentrotus purpuratus Compete with reds for kelp Currently no commercial fishery Smaller than reds (max ~80mm) Forms urchin barrens long-term monitoring sites deforested by purples ~33% of the time—mostly in the east Red sea urchin Strongylocentrotus franciscanus max ~150 mm Regression model to predict GSI Temperature, abiotic factors Reserve versus fished Community data Purples compete with reds

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38 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

39 Santa Barbara San Miguel Santa Rosa Anacapa Santa Cruz GSI is higher in the west a a ab b bc cd d d bcd

40 Red urchin landings 1985-2005 Purple urchin abundance 2007 Shears in prep, NPS—KFM, CDFG data

41 Biomass (gm -2 ) Density (m -2 ) kelp purple urchins red urchins Long-term (1985-2007) E Santa Cruz and Anacapa Shears in prep, NPS—KFM data

42 Biomass (gm -2 ) Density (m -2 ) kelp purple urchins red urchins Long-term (1985-2007) E Santa Cruz and Anacapa Shears in prep, NPS—KFM data

43 Long-term (1985-2007) E Santa Cruz and Anacapa Shears in prep, NPS—KFM data Biomass (gm -2 ) Density (m -2 ) kelp purple urchins red urchins Red urchins have persistently higher biomass inside of the reserves. Reproductive output is ~4 times higher in kelp forests versus urchin barrens

44 manipulate ecology of a managed area to increase profits Purple urchin removals in historical red urchin fishing grounds?  kelp restoration

45 Outline III. Ecology What drives variability in red urchin populations over time and space? How do urchins and fishery profits respond to various management regimes? IV. Management How does gonad quality explain behavior of fishermen? II. Fishing behavior What drives variability in gonad quality (and price) over time? I.Fished quality

46 How do urchins and fishery profits respond to various management regimes? IV. Management

47 Management goals time population size FoFo F reduced F historical today

48 Management goals time population size FoFo F reduced F historical today

49 Management goals time population size or fishery profit FoFo F seasonal quota F historical today

50 Profits may increase with TURFs fishermen race to harvest year-round vs. waiting for optimal quality How much more $ would they make, if they waited? delaying harvest through spatial property rights, TURF’s (Territorial Use Rights in Fisheries)  fishermen’s profits

51 GSI equal across space (sometimes) west central east equal

52 GSI unequal across space (other times) west central east equalunequal E,C W,C

53 Management strategy evaluation (MSE) framework urchin population + urchin fishery “operating model” (ex: current actual status) Data collection (ex: size structure of population and catch with sampling error) Data assessment (ex: compare the mean size of the catch to a target size) Management strategy (ex: set a goal for the next year: if the mean size is < 90 mm, then reduce fishing pressure by 10,000 lbs) run simulation 100 times… and see what maximizes pop and fishery benefits… and evaluate multiple strategies

54 Assess management strategies Seasonal quota (TAC) Individual quotas Minimum size limits Maximum size limits Limited entry Area closures TURFs Combination of various strategies

55 Summary… future goals II. Ecology high kelp and low competitor densities will likely correlate with high red urchin GSI (what are the main drivers?) GSI explains much of the variability in red urchin fishery profits…but what else? I.Fishery a variable management regime over time and space will likely increase fishermen’ profits… (need to take into account the ecological & biological drivers) III. Management

56 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

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58 Current regulations Northern CA: – 89 mm minimum size limit – Jul closed and May-Sept 12 days per month Southern CA: – 83 mm minimum size limit – Apr-Oct 4 days a week open

59 Management evaluation framework (adaptive management) Population model + Fisheries model Alter fleet dynamics, then assess population and fisheries models Optimal management strategy (ex: set guidelines for a seasonal catch limit) (ex: how much more would biomass and profits increase with a seasonal catch limit?)

60 Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO): http://www.cmar.csiro.au/research/mse/

61 Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO): http://www.cmar.csiro.au/research/mse/


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