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Abalone Management in California Presentation to the Fish and Game Commission Mr. Ian Taniguchi and Dr. Laura Rogers-Bennett Department of Fish and Game.

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Presentation on theme: "Abalone Management in California Presentation to the Fish and Game Commission Mr. Ian Taniguchi and Dr. Laura Rogers-Bennett Department of Fish and Game."— Presentation transcript:

1 Abalone Management in California Presentation to the Fish and Game Commission Mr. Ian Taniguchi and Dr. Laura Rogers-Bennett Department of Fish and Game November 7, 2012 Photo: R. Tavernetti

2 Overview History of the abalone fishery Abalone Recovery Management Plan (ARMP) Northern California Fishery, Data and Status Projects and Priorities Partnerships/Collaborations

3 Historic Commercial Fishery Landings

4 Historic Abalone Fishery Commercial and sport fisheries in central and southern CA Relied on size and bag limits and season Scuba/Hooka was allowed No fishery independent density surveys

5 Abalone Recovery and Management Plan ARMP (FG Code §5522): five year development process Comprehensive and cohesive plan –Recovery actions in the south –Management of the fishery in the north Interim and long term plans Adaptive management based

6 Time Density (Abalone/ha) Sustainable Fishery Closure Minimum Viable Population Decline Precautionary Management Strategy 5,000 2,000 3,000 6,600

7 ARMP Catch Adjustment Table From ARMP Table 7-2

8 ARMP Site Closure Table From ARMP Table 7-4

9 Management Goals Fishery Goals –Maintain densities at or above 6,600 ab/ha –More adaptive and precise management Population Goals –Prevent densities declining to <2,000 ab/ha

10 Why is density so important? Close together = high fertilization success Far apart = low fertilization success High density = reproductive population Babcock and Keesing 1999

11 Distance and Density Button and Rogers-Bennett in prep

12 Fishery Collapse at Low Density National Park Service surveys Channel Is. Johnson’s Lee North < 2,000 red ab/ha

13 California Abalone Fishery World class fishery landing >400 MT The largest abalone species in the world Abalone fishing part of natural heritage of California

14 Fishery Information Important fishery for the north coast economy 35,000-40,000 fishers 264,000 abalone/year 71% of fishers get daily bag limit – high quality fishery

15 Fishery Monitoring Program Monitor 8 Index sites Representative of the fishery –Density of fished portion stock –Sustainable fishery on fishing grounds Monitoring sites encompass 44% of overall fishery catch (67% Sonoma Co.) Direct feedback to Fishery Management Plan Photo: S. Fitzgerald

16 *total number of red abalone harvested = 1,352,353 Abalone Catch by County (2002-2010)

17 Survey Design 8 Index sites (4 Sonoma, 4 Mendocino) Random stratified sampling (by depth) 36 transects per site 3 sites per year surveyed

18 Transect Protocol Insert video clip of transect

19 Purpose of Monitoring Fishery management To determine if density changed over time and to what degree Science-based density answer to use for abalone management Survey designed to have sufficient statistical power to address this question

20 Why We Use Statistics Used to detect strong patterns in the data Determine if the average densities are statistically significantly different over time Statistical tools  Analysis of Variance (ANOVA)

21 Power of the Sampling Program All five are interrelated: 1.Alpha level (set significance p < 0.05) 2.Power level (set 1-beta > 0.80) 3.Size of the effect (percent change) 4.Variance sample 5.Sample size -- We can detect changes in density that are greater than 15%.

22 Abalone Density 2012 *Averages are significantly different (ANOVA p<0.001) 35% Decline

23 Statistics Results The averages are statistically significantly different Alpha = p (significance level) p < 0.001 = Highly significant since P < is lower than the desired 0.05 significant level

24 *Averages are significantly different by county over time (ANOVA p<0.001) Abalone Density 2012 by County 60% Decline

25 Sonoma County Density Decreases Post-HAB

26 Harmful Algal Bloom (Red Tide) Aug. 2011 - Abalone mortality Impacted half of the fishing grounds Sonoma County Microalgae Gonyaulax spinifera Ongoing monitoring of both the abalone algae Photo: Nate Buck Fort Ross 2011

27 Suggested Next Steps Northern California Consider regulatory action based on the Fish and Game Commission’s ARMP density triggers

28 ARMP Directed Projects Recovery Fishery management Marine Protected Area (MPA) monitoring Illegal take

29 Recovery Projects Endangered species restoration –White abalone restoration (NOAA Grant) –Black abalone recovery team Recovery monitoring –Throughout range White Abalone Recruitment Traps

30 Active recovery feasibility studies –Aggregation/Translocation studies –Out planting studies Recovery Projects (cont’d) Pink Abalone Translocation Photo: D. Stein

31 Fishery Management Projects Northern California –Index site surveys –Creel survey –Report Card data analysis Essential Fishery Information –Fecundity studies –Recruitment studies –Red Tide impact study –Movement studies –Population genetics studies –Disease Red Tide Plankton Sample Photo: D. Stein

32 Red Abalone Reproduction Females Green gonad Size First Repro. Mature 105.7mm (4.1 inches) - Rogers-Bennett et al. 2004

33 Abalone Recruitment Young of the Year <21mm Rogers-Bennett et al. 2004 Northern California: 12 ARMS Van Damme 2005

34 Abalone Disease Shellfish Health Lab Withering Syndrome Bacteria spreading to the North Test San Miguel Island abalone HealthyDiseased Red Abalone

35 San Miguel Island (SMI) Fishery Consideration –SMI survey (2006-2008) –Abalone Advisory Group –Stock assessment –Risk assessment –Harvest study proposal Fishery Projects (cont’d) SMI Survey Participants 2006

36 Marine Protected Areas Importance to abalone management –They allow comparisons between no take and fished sites –May provide large adult females to produce many eggs –May help supply larvae to fished sites. Fishing effort shift concerns –Approx 9% (16% North Central) of catch impacted by MPAs

37 Combating Illegal Fishing Report card/tag system Processed abalone size study –(Rogers-Bennett and Melvin 2007) Forensic genetics studies Survey questionnaire on illegal take –(Blank and Gavin 2009)

38 Partnerships/Collaborations Federal Agencies –NOAA Fisheries, National Park Service, Sanctuaries, US Navy Constituents –Commercial and Recreational Academic Institutions –UCD, UCSC., Cal. State Univ., Virginia Tech. Public Aquariums –Long Beach Aqua. of the Pacific, Cabrillo Aqua. Non-Governmental Organizations (NGO) –Coast Keeper Alliance, Reef Check

39 Summary DFG provides a high quality recreational abalone fishery DFG has built a quality abalone management program Program is responsive to the needs of the resource and fishery Program conserves abalone resources and supports recreational fishing in California

40 Thank You Dr. Laura Rogers-Bennett - lrogersbennett@dfg.ca.gov Mr. Ian Taniguchi - itaniguchi@dfg.ca.gov Department of Fish and Game Marine Region ARMP: http://www.dfg.ca.gov/marine/armp/index.asp

41 Note: the following slides are for use during the questions and answers session

42 Abalone Fishery by Species

43 Density = Fishing Success CountyRock pickersDivers Mendocino75%74% Sonoma45%78% Both counties68%76% Total (pickers and divers)71%

44 Fishery Demographics

45 Abalone Density 2011 *Averages are significantly different (ANOVA p=0.0006) - 27% change in overall density.

46 Catch History

47 Survivorship 0 20 40 60 80 100 20-Nov9-Jan28-Feb18-Apr7-Jun27-Jul15-Sep Date 2007-08 Survivorship (%) ELNLANAMB


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