Growth, mortality, and reproductive seasonality of California Halibut (Paralichthys californicus): a biogeographic approach

Transcription

1 Growth, mortality, and reproductive seasonality of California Halibut (Paralichthys californicus): a biogeographic approach Cheryl L. Barnes Moss Landing Marine Laboratories Richard M. Starr California Sea Grant Paul N. Reilly CA Dept. Fish and Wildlife (CDFW) Collaborators Travis Tanaka, CDFW Kristine Lesyna, CDFW

2 California Paralichthyidae Pleuronectidae Alaska 67 lb (30.4 kg) lb (218.6) 2014 photo: E. Villareal photo: Devin Brown

3 Varied Environmental Conditions Lead to Distinct Biogeographic Regions Pt Conception Allen et al. 2006

4 Marine Fishes with Widespread Distributions Leads to Development of Metapopulations all fish drawings from Allen et al. 2006

5 California Halibut, Paralichthys californicus photo: Joe Leauseau

6 California Halibut Widespread Distribution Spans Multiple Biogeographic Regions CDFW stock assessment cenca soca Pt Conception Allen et al. 2006

7 California Halibut Widespread Distribution Spans Multiple Biogeographic Regions San Francisco Pt Conception Allen et al. 2006

8 California Halibut Widespread Distribution Spans Multiple Biogeographic Regions cenca soca Pt Conception Allen et al. 2006

9 California Halibut Widespread Distribution Spans Multiple Biogeographic Regions Sea Surface Temperature Chlorophyll A N San Francisco San Francisco San Francisco San Francisco San Francisco San Francisco San Francisco San Francisco San cenca Francisco San cenca Francisco San Francisco soca San Francisco soca Point Conception CeNCOOS (NOAA Coast Watch Program) 2014

10 California Halibut Stock Assessment Region-specific Stock Models - sex-structured estimates included: - growth - mortality - selectivity Maunder et al limited composition data for central California - some parameters fixed using soca data photo: Liza Schmidt

11 Master s Thesis Research Question Do life history characteristics differ by region? CALIFORNIA HALIBUT photo: CitySkylines central California southern California

12 Master s Thesis Research Question Do life history characteristics differ by region? productivity growth mortality

13 Master s Thesis Research Question Do life history characteristics differ by region? reproductive seasonality growth mortality

14 Master s Thesis Research Question Do life history characteristics differ by region? reproductive seasonality growth total mortality

15 Methodology: Study Design CA NV San Francisco Santa Cruz Moss Landing Monterey sample sizes cenca = 1296 soca = 760 Morro Bay Port San Luis Santa Barbara Ventura Oxnard Marina Del Rey Point Conception San Pedro Dana Point La Jolla

16 Methodology: Growth length-at-age data, von Bertalanffy growth curves reproductive seasonality growth total mortality

17 Results: von Bertalanffy Growth Curves female California Halibut, both regions L(t) cenca = 1049 (1 e -0.21t ) L(t) soca = 1304 (1 e -0.12t ) Fork Fork Length Length (mm) (mm) Age (yr) central California southern California n (cenca) = 743 n (soca) = 615

18 Results: von Bertalanffy Growth Curves female California Halibut, both regions L(t) cenca = 1049 (1 e -0.21t ) L(t) soca = 1304 (1 e -0.12t ) Fork Fork Length Length (mm) (mm) L central California southern California K Age (yr) central California southern California n (cenca) = 743 n (soca) = 615

19 Results: von Bertalanffy Growth Curves male California Halibut, both regions L(t) cenca = 820 (1 e -0.25t ) L(t) soca = 1048 (1 e -0.15t ) Fork Length (mm) central California southern California Age (yr) n (cenca) = 553 n (soca) = 145

20 Results: von Bertalanffy Growth Curves male California Halibut, both regions L(t) cenca = 820 (1 e -0.25t ) L(t) soca = 1048 (1 e -0.15t ) Fork Length (mm) L * central California southern California * K central California southern California Age (yr) n (cenca) = 553 n (soca) = 145

21 Results: von Bertalanffy Growth Curves California Halibut, both sexes and regions Fork Length (mm) cenca cenca Age (yr)

22 Results: von Bertalanffy Growth Curves California Halibut, both sexes and regions 1400 Fork Length (mm) soca cenca soca cenca Age (yr)

23 Methodology: Reproductive Seasonality temporal spawning and larval density data reproductive seasonality growth total mortality

24 Results: Reproductive Seasonality peak spawning, regional comparisons 5.5 central CA Mean Gonadosomatic Index Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec n (cenca) = 97

25 Results: Reproductive Seasonality peak spawning, regional comparisons Mean Gonadosomatic Index 5.5 central CA southern CA Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Corrected Mean Laval Density (no. per 10 m 2 ) larval density data, CalCOFI 1980 to 2011

26 Results: Reproductive Seasonality peak spawning, regional comparisons Mean Gonadosomatic Index 5.5 central CA southern CA Mexico Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Corrected Mean Laval Density (no. per 10 m 2 ) larval density data, CalCOFI 1980 to 2011

27 Results: Reproductive Seasonality peak spawning, regional comparisons Mean Gonadosomatic Index 5.5 central CA southern CA Mexico 4.5 cenca? Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Corrected Mean Laval Density (no. per 10 m 2 ) larval density data, CalCOFI 1980 to 2011

28 Results: Reproductive Seasonality peak spawning, regional comparisons Mean Gonadosomatic Index central CA southern CA Mexico cenca? MX May cenca Jul soca Jun 2.5 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Corrected Mean Laval Density (no. per 10 m 2 ) larval density data, CalCOFI 1980 to 2011

29 Methodology: Mortality age frequency data, catch curve analysis reproductive seasonality growth total mortality

30 Methodology: Mortality age frequency data, catch curve analysis 20 LN Frequency 10 not fully recruited to the fishery 0 ANCOVA p (slope) = Z p (intercept) = relative abundance Age (yr)

31 Results: Instantaneous Total Mortality female California Halibut, both regions LN Frequency central California y = x R 2 = 0.623, p = southern California y = x R 2 = 0.826, p < ANCOVA p (mortality) = p (relative abundance) = Age (yr)

32 Results: Instantaneous Total Mortality male California Halibut, both regions LN Frequency central California y = x R 2 = 0.483, p = southern California y = x R 2 = 0.859, p = ANCOVA p (mortality) = p (relative abundance) = Age (yr)

33 Results: Instantaneous Total Mortality California Halibut, both sexes and regions 5 4 LN Frequency Age (yr)

34 Results: Instantaneous Total Mortality California Halibut, both sexes and regions 5 4 LN Frequency Age (yr)

35 Master s Thesis Research Question Do life history characteristics differ by region? CALIFORNIA HALIBUT photo: CitySkylines central California southern California

36 Results Summary: California Halibut

37 Results Summary: California Halibut - cenca Halibut grow faster, but attain smaller maximum sizes than soca Halibut

38 Results Summary: California Halibut - cenca Halibut grow faster, but attain smaller maximum sizes than soca Halibut - California Halibut spawn earlier at lower latitudes during summer 1) MX: May 2) soca: June 3) cenca: July - relatively protracted spawning south of Point Conception?

39 Results Summary: California Halibut - cenca Halibut grow faster, but attain smaller maximum sizes than soca Halibut - California Halibut spawn earlier at lower latitudes during summer 1) MX: May 2) soca: June 3) cenca: July - relatively protracted spawning south of Point Conception? - there is no difference in California Halibut mortality by sex or region

40 Informing the Next Stock Assessment - region-specific estimates provided to CDFW - new data available for central stock model photo: Richard Scangarello

41 Thesis Committee Rick Starr Jim Harvey Scott Hamilton Paul Reilly CA Department of Fish and Wildlife Travis Tanaka Kristine Lesyna CDFW Port Samplers Adrienne Vincent Kim Penttila Kyle Evans Kathryn Crane Tom Barnes Moss Landing Marine Laboratories Fisheries & Conservation Bio Lab Ichthyology Lab MLML Faculty, Staff, and Students Gregor Cailliet Michael Graham James and Billy Cochran Gary Adams Kris Machado Acknowledgments Selected Fishermen Ed Burrell Larry Ankuda Allen Bushnell Andrew Harmer David Shorty Reins Jim Russell Richard Scangarello John Snyder Kurtis Williams Field and Lab Interns Alexandra Aines Daniel Anaya Kaitie Beck Adam Chorazyczewski Caitrin Doles Chris Giordano Hallie Heath Serena Lomonico Rhiannon McCollough Elizabeth Schurig Nikki Siababa Aaron Sloan Emily Stollmeyer Further Support Nancy Brown Jennifer Chatham Jennifer Chiu Christian Denney Will Fennie Ryan Fields Scott Gabara Nick Ingram Liz McHuron Gabriela Navas Lexi Rosichan Angela Szesciorka Grant Waltz Devona Yates

42 Additional Financial & Logistical Support Graduate Equity Fellowship C. F. and L. V. Burmahln Scholarship Associated Students Advocacy Award Dr. Earl M. Myers and Ethel M. Myers Oceanographic and Marine Biology Trust MLML Scholar Award Xiphias Martin Scholarship

43 Questions? Questions?