Recruitment of Juvenile Gags in the Eastern Gulf of Mexico and Factors Contributing to Observed Spatial and Temporal Patterns of Estuarine Occupancy

We conducted a comprehensive examination of long-term (10+ years) fisheries-independent data to characterize the spatial and temporal patterns of habitat selection and recruitment of juvenile gags Mycteroperca microlepis in four eastern Gulf of Mexico estuaries in Florida: Apalachicola Bay, Cedar Key, Tampa Bay, and Charlotte Harbor. Results from generalized linear modeling and habitat suitability analyses indicated that juvenile gags selected euhaline or polyhaline habitats with sloping bottoms and extensive coverage of submerged aquatic vegetation; the observed patterns were similar among estuaries. Latitudinal differences in the timing and duration of estuarine occupancy by juvenile gags were evident, with individuals appearing earlier and remaining later in more southerly estuaries. Significant interannual variability in recruitment of juvenile gags was evident within all estuaries, with high juvenile recruitment evident every 2 to 4 years. Continued efforts toward characterizing year-class strength through the development of a regional index of juvenile gag recruitment may be useful in forecasting fisheries productivity, although such efforts would benefit greatly from an increased understanding of the relative contribution of presumed estuarine nurseries to nearshore populations.