Characterizing Gray Snapper (Lutjanus griseus) Life History in the Northcentral Gulf of Mexico

Project Leader:Edward Kim, Master’s Student

Project Details

Background:

Gray Snapper (Lutjanus griseus) constitute a significant recreational fishery and minor commercial fishery throughout the Gulf of Mexico, and a recent assessment in 2018 determined that the overall stock has been undergoing prolonged overfishing. Spatiotemporal gaps in our understanding of these fish that could better inform management still exist, particularly within the northcentral Gulf of Mexico. The absence of regional baseline data, combined with projections of population growth due to climatic warming, highlights the need for supplementary monitoring efforts. This study will investigate the abundance and distribution of Gray Snapper in the Alabama Artificial Reef Zone through the analysis of remotely operated vehicle footage from 2011 to 2019. This study will also examine the age, growth, and reproduction of Gray Snapper through predominantly fishery-dependent sampling in the coastal and offshore waters of Alabama and Mississippi. The findings from these studies will introduce new data for incorporation in future assessments, provide guidance for management decisions, and promote informed support of the fishery.

Objectives:

  • Investigate Gray Snapper abundance and distribution in the Alabama Artificial Reef Zone
  • Assess Gray Snapper age, growth, and reproduction in the northcentral Gulf of Mexico

Approach:

MaxN count data obtained from these videos will be used to generate a standardized index of relative abundance to evaluate annual population trends and characterize habitat and depth usage. Sex-specific growth models will be constructed from length-age and weight-length data, mortality rates will be estimated from a catch curve based on fisheries-dependent catch data, and histological analyses will determine mean estimates of age-at-maturity and length-at-maturity as well as seasonal spawning dynamics.

Funding Sources: Alabama Marine Resources Division, Coastal Conservation Association, University of South Alabama