Age sample sizes and their effects on growth estimation and stock assessment outputs: Three case studies from U.S. West Coast fisheries
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

For very narrow results

When looking for a specific result

Best used for discovery & interchangable words

Recommended to be used in conjunction with other fields

Dates

to

Document Data
Library
People
Clear All
Clear All

For additional assistance using the Custom Query please check out our Help Page

The NOAA IR serves as an archival repository of NOAA-published products including scientific findings, journal articles, guidelines, recommendations, or other information authored or co-authored by NOAA or funded partners. As a repository, the NOAA IR retains documents in their original published format to ensure public access to scientific information.
i

Age sample sizes and their effects on growth estimation and stock assessment outputs: Three case studies from U.S. West Coast fisheries

Filetype[PDF-1.76 MB]



Details:

  • Journal Title:
    Fisheries Research
  • Personal Author:
  • NOAA Program & Office:
  • Description:
    Age estimates are often used as conditional age-at-length (CAAL) data in stock assessment models to internally estimate growth and other life history parameters of fish populations. Obtaining sufficient numbers of age estimates is not a trivial task, as it requires considerable sampling effort, the development of aging criteria, the validation of age observations, and, finally, the production aging of sufficient numbers of age structures to inform the assessment models. In this study, we evaluated the influence of CAAL data in several assessment models of West Coast groundfish, by both randomly selecting only portions of available CAAL data and by selecting intermittent numbers of years of CAAL data for inclusion in models. These sensitivity tests were conducted on recent stock assessment models for Blackgill Rockfish (Sebastes melanostomus), Bocaccio (Sebastes paucispinis), and Pacific Sanddab (Citharichthys sordidus), as these three species represent a fairly wide range of life history types. The results showed that for the Bocaccio model, the assessment outputs from model runs with reduced numbers of CAAL data were very comparable with the model run with all available data. However, when CAAL data were reduced, the Blackgill and Sanddab models estimated different spawning outputs, stock depletions, and growth functions. Reducing CAAL data in these two models also resulted in larger estimation uncertainties in the assessment outputs. Overall, our results suggest that it is important to obtain more age data from long-lived species over as long a time span as possible, and aging samples from intermittent years may be considered if there are constraints in time or effort to age all available samples.
  • Source:
    Fisheries Research, 180, 92-102
  • DOI:
  • ISSN:
    0165-7836
  • Format:
  • Publisher:
  • Document Type:
  • License:
  • Rights Information:
    CC0 Public Domain
  • Compliance:
    Library
  • Main Document Checksum:
  • Download URL:
  • File Type:

Supporting Files

  • No Additional Files
More +

You May Also Like

Checkout today's featured content at repository.library.noaa.gov

Version 3.27.1