California’s Gold: Ensuring a profitable and sustainable sea urchin fishery

California’s Gold: Ensuring a profitable and

sustainable sea urchin fishery

Sarah Teck

14 April 2011

CINMS J. Maassen

Santa BarbaraSan Miguel

Santa Rosa

Anacapa

Santa Cruz

California’s Gold(5th largest fishery)

~66% is harvested from here

incabrain.com

~52% is landed here

Red urchin fishery landings have dropped

Data: CDF&G

~ 52 ~11

million lbs

Red urchin ex-vessel prices have dropped

~$34~$6 million

~ 52 ~11

million lbs

Data: CDF&G

Red urchin effort has changed over time

Data: CDF&G

Data: CDF&G

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 NiñoEl Niño

El Niño

↓ Japanese economy

↑ market competition

(Kalvass and Hendrix 1997)

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)

P=0.0045R2=0.71

Value increases with gonad quality

% gonad of whole body weight

Quality varies seasonally

west

central

east



west

central

east

{



west

central

east

{

}



west

central

east

{

}

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

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


Santa Rosa

Anacapa

Santa Cruz

California’s Gold

(5th largest fishery)

~66% is harvested from here

www.incabrain.com

~52% is landed here

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

Outline

III. EcologyWhat 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


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?

Santa Barbara Port sampling

400 boats surveyed200 boats GSIDec 2008-present

location, effort, landings, GSI, price…

Port sampling fished sites

P=0.0045R2=0.71

price is highly correlated with GSI

GSI is highly variable

variation partially explained by space

westcentraleast

GSI varies seasonally

westcentraleast

GSI decreases during spawning

westcentraleast

spawning

GSI increases during regrowth

westcentraleast

spawning gonadal regrowth

Outline


II. Fishing

behavior


I. Fished

quality


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…

Outline



II. Fishing

behavior


I. Fished

quality


Santa Rosa

Anacapa

Santa Cruz


Regression model to predict GSI• Temperature, abiotic factors • Reserve versus fished• Community data

Steep temperature gradient

(Blanchette et al 2007)


(Behrens & Lafferty 2004, Lafferty & Behrens 2005)


Reserves may affect GSI

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


Purples compete with reds

Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO) ecosystem research and monitoring (fish and benthic subtidal sampling)

32 sites summer 200927 sites summer 2010


Santa Rosa

Anacapa

Santa Cruz

GSI is higher in the west

a aab

bbc cdcd

d d bcd

Red urchin landings 1985-2005

Purple urchin abundance 2007

a)

b)

Figure 4. (a) Spatial distribution of red urchin landings from 1985 to 2005 in the CINMS (landings are assigned to 10 x 10 nautical mile blocks as reported to CA Dept. of Fish and Game), and (b) spatial variation in purple urchin abundance (the larger the circle the greater the density; Data: PISCO/SBC-LTER)

<1

1-5

6-10

11-20

20-30

% Landings

<1

1-5

6-10

11-20

20-30

% Landings



33.8

34

34.2

34.4

34.6

-120.6 -120.4 -120.2 -120 -119.8 -119.6 -119.4 -119.2

33.8

34

34.2

34.4

34.6

-120.6 -120.4 -120.2 -120 -119.8 -119.6 -119.4 -119.2



a)

b)

Figure 4. (a) Spatial distribution of red urchin landings from 1985 to 2005 in the CINMS (landings are assigned to 10 x 10 nautical mile blocks as reported to CA Dept. of Fish and Game), and (b) spatial variation in purple urchin abundance (the larger the circle the greater the density; Data: PISCO/SBC-LTER)

<1

1-5

6-10

11-20

20-30

% Landings

<1

1-5

6-10

11-20

20-30

% Landings


Shears in prep, NPS—KFM, CDFG data

0

2

4

6

8

10

12

14D

en

sity

(m-2

)Reserve (n=2)

Fished (n=5)

0

10

20

30

40

50

60

70

80

De

nsi

ty (

m-2)

Reserve (n=2)

Fished (n=5)

0

1

2

3

4

5

6

7

8

De

nsi

ty (

m-2)

Reserve (n=2)

Fished (n=5)

Kelp

Purple urchins

Red urchins

0

500

1000

1500

2000

2500

De

nsi

ty (

m-2

)

Reserve (n=2)

Fished (n=5)

Red urchin biomass

Bio

ma

ss (

g m

-2)

kelp

purple urchins

red urchins

0

500

1000

1500

2000

2500

Reserve (n=2)

Fished (n=5)

Red urchin biomass

Long-term (1985-2007)E Santa Cruz and Anacapa

Shears in prep, NPS—KFM data

0

2

4

6

8

10

12

14D

en

sity

(m-2

)Reserve (n=2)

Fished (n=5)

0

10

20

30

40

50

60

70

80

De

nsi

ty (

m-2)

Reserve (n=2)

Fished (n=5)

0

1

2

3

4

5

6

7

8

De

nsi

ty (

m-2)

Reserve (n=2)

Fished (n=5)

Kelp

Purple urchins

Red urchins

0

500

1000

1500

2000

2500

De

nsi

ty (

m-2

)

Reserve (n=2)

Fished (n=5)

Red urchin biomass

Bio

ma

ss (

g m

-2)

kelp

purple urchins

red urchins

0

500

1000

1500

2000

2500

Reserve (n=2)

Fished (n=5)

Red urchin biomass


Shears in prep, NPS—KFM data

0

2

4

6

8

10

12

14D

en

sity

(m-2

)Reserve (n=2)

Fished (n=5)

0

10

20

30

40

50

60

70

80

De

nsi

ty (

m-2)

Reserve (n=2)

Fished (n=5)

0

1

2

3

4

5

6

7

8

De

nsi

ty (

m-2)

Reserve (n=2)

Fished (n=5)

Kelp

Purple urchins

Red urchins


Shears in prep, NPS—KFM data0

500

1000

1500

2000

2500

De

nsi

ty (

m-2

)

Reserve (n=2)

Fished (n=5)

Red urchin biomass

Bio

ma

ss (

g 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

0

500

1000

1500

2000

2500

Reserve (n=2)

Fished (n=5)

Red urchin biomass

• manipulate ecology of a managed area to increase profits

• Purple urchin removals in historical red urchin fishing grounds?kelp restoration

Outline



IV. Management


II. Fishing

behavior


I. Fished

quality


IV. Management

Management goals

time

population size

Fo

Freduced

Fhistorical

today

Management goals

time

population size

Fo

Freduced

Fhistorical

today

Management goals

time

population sizeor

fishery profit

Fo

Fseasonal quota

Fhistorical

today

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

GSI equal across space (sometimes)

westcentraleast

equal

GSI unequal across space (other times)

westcentraleast

equal unequal

E,CE,C

W,C

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

Assess management strategies

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

Summary… future goals

II. Ecologyhigh 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

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

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

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?)

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

http://www.cmar.csiro.au/research/mse/

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

http://www.cmar.csiro.au/research/mse/

Documents

California’s Gold: Ensuring a profitable and sustainable sea urchin fishery