jurado molina

Developing a statistical-multispecies framework for a predator-prey system in the eastern Bering Sea:: 

Developing a statistical-multispecies framework for a predator-prey system in the eastern Bering Sea: Jesús Jurado-Molina University of Washington Jim Ianelli, Patricia Livingston Alaska Fisheries Science Center

Ecological considerations in fisheries management: 

Ecological considerations in fisheries management Competition Predation Environmental Regime Shifts Habitat alteration

Scientific Framework to provide ecosystem-based advice in the Bering Sea: 

Scientific Framework to provide ecosystem-based advice in the Bering Sea Main goals for protecting ecosystem attributes: Maintain predator/prey relationships Maintain energy flow and balance Maintain diversity Tools: Multispecies models (biological interactions) Multispecies models (technological interactions) Full ecosystem models (ECOPATH, ECOSIM…)

Multispecies models (biological interactions): 

Multispecies models (biological interactions) Deterministic models: Multispecies virtual population analysis (MSVPA) Multispecies forecasting model (MSFOR) Statistical models: Multispecies statistical model (MSM)

Multispecies VPA: 

Multispecies VPA

MSVPA-MSFOR models: 

MSVPA-MSFOR models

Statistical catch-at-age models: 

Statistical catch-at-age models

Multispecies statistical model: 

Multispecies statistical model

MSM: assumptions: 

MSM: assumptions Separable fishing mortality assumption (Fa,t = saFfull,t) M= M1+ M2 Constant annual predator ration Stomach content measured without error

Advantages of MSM:: 

Advantages of MSM: Multispecies approach Measuring indirect effects of fishing We can use the tools used in single-species stock assessments Likelihood profile Bayesian analysis (posterior distributions) Decision analysis Model selection (Akaike’s information criterion,likelihood ratio ) Able to make comparisons with the single-species stock assessment models in the same statistical framework

MSM (previous version): 

MSM (previous version) Included only two species (walleye pollock and Pacific cod) Set up in Excel Fitted only to catch at age data, total catch, bottom trawl survey and EIT survey Updated to 2002 data

MSM (new version): 

MSM (new version) Three species, walleye pollock, Pacific cod and arrowtooth flounder Set up in AD model builder Fitted to total catch data, bottom trawl survey, pollock age composition, Pacific cod and arrowtooth length composition (from fishery), survey age and size composition, EIT survey (pollock) Updated to 2006 data

MSM system for the Bering Sea: 

MSM system for the Bering Sea Walleye pollock Pacific cod Fishery Arrowtooth flounder

Walleye pollock N3+: 

Walleye pollock N3+

Pacific cod N3+: 

Pacific cod N3+

Bottom trawl survey fit: 

Bottom trawl survey fit

Total catch fit: 

Total catch fit

Average predation mortality at age: 

Average predation mortality at age

Pollock predation mortality: 

Pollock predation mortality

Walleye pollock predation mortality in 1979 (from MCMC with 3 million iterations): 

Walleye pollock predation mortality in 1979 (from MCMC with 3 million iterations)

Predation mortality comparison: 

Predation mortality comparison Slope = 0.9±0.02 r2 = 0.92

Comparison of causes of death (numbers) - Pollock: 

Comparison of causes of death (numbers) - Pollock

Comparison of causes of death (biomass) - Pollock: 

Comparison of causes of death (biomass) - Pollock

Comparison of causes of death (spawning biomass) - Pollock: 

Comparison of causes of death (spawning biomass) - Pollock

Walleye pollock Recruitment: 

Walleye pollock Recruitment

Future tasks: 

Future tasks Addition of the complete set of stomach content data Module for model projections Module for technological interactions

Developing a statistical-multispecies framework for a predator-prey system in the eastern Bering Sea:: 

Developing a statistical-multispecies framework for a predator-prey system in the eastern Bering Sea: Jesús Jurado-Molina University of Washington jjurado@u.washington.edu Jesus.Jurado-Molina@noaa.gov