U.S. flag An official website of the United States government.
Official websites use .gov

A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS

A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

i

Age, growth, and mortality of threatened Warsaw grouper, Hyporthodus nigritus, in the Gulf of Mexico



Details

  • Journal Title:
    Fisheries Research
  • Personal Author:
  • NOAA Program & Office:
    NOAA General Documents
  • Description:
    Warsaw grouper (Hyporthodus nigritus) in the Gulf of Mexico (GoM) are currently managed as a single-stock; however, patchy distribution of suitable habitat may promote the development of discrete populations with different life history characteristics thereby complicating conservation policy. We estimated ages and age-length relationships of Warsaw grouper from different geographic regions in the GoM and applied von Bertalanffy growth functions (VBGF) to estimate growth parameters (L∞ and K) for each region. Otolith-based ages ranged from 1 to 91 years and estimated L∞ and growth coefficient (K) derived from the VBGF for all Warsaw grouper combined were 188.8 cm total length (TL) and 0.034 respectively. Region-specific growth parameters were similar for most of the GoM when VBGFs were limited to Warsaw grouper < 25 years old, though growth was considerably faster from the southeast GoM. When our age-length key was applied to fisheries-dependent length data from the GoM in 2001–2006 and 2011–2016, this fishery was comprised primarily of Warsaw grouper < age-1, but the mean age increased between catches from 2001 to 2006 (4.7 ± 8.3) and 2011–2016 (7.6 ± 6.4). Instantaneous mortality rates (Z) based on the decline of log abundance on age indicated relatively low Z rates across the four regions (range: 0.09−0.18), with a significantly higher mortality rate in the western GoM (0.17) than the eastern GoM (0.08). In this study we also observed a greater longevity (91 years) for the species than previously documented, greater than double the longevity used to develop current management policy.
  • Keywords:
  • Source:
    Fisheries Research, 243, 106097
  • DOI:
  • ISSN:
    0165-7836
  • Format:
    PDF
  • Publisher:
    Elsevier BV
  • Document Type:
    Journal Article
  • Rights Information:
    Accepted Manuscript
  • Compliance:
    Library
  • Main Document Checksum:
    urn:sha256:d3f9114a247cbfde5d97213dee19d8bc55c45e46027179cdb9573078bcae7279
  • Download URL:
  • File Type:
    Filetype[PDF - 1009.00 KB ]
PREVIOUS
ON THIS PAGE
Details
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.
BACK TO TOP