Abstract
Habitats used by juvenile fishes can dramatically differ among estuaries. Thus, it is important to apply life-history models in a variety of estuarine settings to fully define a species' suite of juvenile habitats. For common Snook, Centropomus undecimalis (Bloch, 1792), juveniles (15-350 mm standard length, SL) are found in areas distinct from those of adults, and their geographic locations and habitat affinities change through ontogeny. To determine the locations of juvenile common Snook habitat in Charlotte Harbor (a large subtropical estuary in southwest Florida) and to describe changing habitat affinities through ontogeny, both fixed-site (1991-1995; 2003-2004) and stratified-random sampling (1996-2002) were conducted. These data were compared to those similarly collected in the Indian River Lagoon (eastcentral coast) and Tampa Bay (west-central coast), Florida, where the generalized life-history model of common Snook has been derived. Small juvenile Snook (<= 150 mm SL) were collected primarily during fall and winter in remote coastal wetlands of Charlotte Harbor, and were not abundant in riverine habitats where they have been reported in the other two Florida estuaries. In Charlotte Harbor, < 3% of small juvenile Snook captured during stratified-random sampling were found within riverine habitats compared to 67% in the Indian River Lagoon, and 97% in Tampa Bay. Larger juveniles (151-350 mm SL) in Charlotte Harbor were collected at entrances to creek networks and marsh ponds. These data suggest that small juveniles occupy coastal-wetland pond and creek networks and subsequently inhabit creek mouths as large juveniles before dispersing more broadly throughout the estuary. Habitat and geomorphological differences among the estuaries may explain less use of riverine habitats by juvenile common snook in Charlotte Harbor, and more exclusive use of remote coastal wetlands.