Prepared for the Center for Independent Experts By

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2011
• Subjects: Bering Sea; Gulf of Alaska; Pacific; Alaska
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.364.5218; http://209.112.168.2/npfmc/PDFdocuments/catch_shares/Pcod/PcodModelsRev411Oliveria.pdf

This CIE review covers the stock assessment models for the stocks of Pacific cod in the Eastern Bering Sea and Gulf of Alaska. This reviewer was impressed by the amount and quality of work carried out on the assessment models for these stocks, and by the high standard of data collection and analyses that underpin these models. The best scientific information available appears to have been used throughout in the stock assessment models. Recommendations cover a number of areas, as stipulated in the Terms of Reference. These include ongoing support for the age-determination work and any work that would advance the Nichol et al. study on survey catchability, as well as a suggestion for the inclusion of temperature data, if practicable, to help better model annual variation in survey catchability. The current use of the Jensen-based estimates of natural mortality, and external estimation of both between-individual variability in size-at-age and input sample sizes for size and age composition data are supported, as are the use of the Nichol et al. study to tune survey catchability, the practice of fixing at least one fishery selectivity to be asymptotic, and the partitioning of data to allow for data features and limitations in SS functionality. Survey data are a key input to the assessment models, and should remain so, with fishery CPUE included