Title: Herring Program – Modeling and stock assessment of PWS herring
Project Year and Number: 2017: 17120111-C
Other Fiscal Years and Numbers for this Project: None
Principal Investigator (PI): Trevor Branch
Assisting Personnel: None
Injured Resources Addressed: Not Specified
Abstract: Prince William Sound (PWS) herring collapsed shortly after the Exxon Valdez oil spill, and has yet to recover. Here, we proposed a modeling component to the long-term herring monitoring project, which has as its chief goal an understanding of the current status of PWS herring, the factors affecting its lack of recovery, and an assessment of research and fishery needs into the future, with the following key products:
1. The core product of the modeling project is the maintenance and updating of the new Bayesian age-structured assessment (BASA) model based on the ASA model used by ADF&G, including annual assessment updates of PWS herring and the revision of BASA to fit to new data sources such as the age-0 aerial survey, condition data, and updated age at maturity.
2.Adapting the BASA model to better model the disease component of natural mortality. Specifically, this would be based on new methods for detecting antibodies of viral hemorrhagic septicemia virus (VHSV) in archival and planned future collections of herring serum.
3. Continued collection and expansion of catch, biomass, and recruitment time series from all herring populations around the world to place the lack of recovery of PWS herring into context given patterns of change in herring populations around the world.
4. An initial exploration of factors that may be used to predict herring recruitment, including oceanography, climate, competition, and predation.
5. A management strategy evaluation to test alternative harvest control rules for managing the fishery in the future, given realistic variability in productivity over time, and the possibility that the population has moved into a low productivity regime. Ecological, economic and social factors would be considered in the MSE.
6. Simulations to evaluate which data sources are the most useful in assessing future herring biomass, based on an MSE of the impact of each form of data on the accuracy of the BASA model.
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Proposal: View PDF (706 KB)
Funding Recommendations: View
Funding Detail For: 2017
Quarterly Project Tasks For: 2017
Annual Report: 2017: Due 09/01/2017
Final Report: Draft Final Report Due 4/15/18
Publications from this Project: None Available