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A population's fidelity to spawning sites and variation in the strength of site fidelity among individuals are influential components of fish population dynamics. The literature on fidelity to aggregation sites is dominated by studies on marine species, whereas less is known about the fidelity of euryhaline species to spawning aggregation sites. We used passive acoustic telemetry to quantify intra-annual and interannual site fidelity and resident habitat associated with spawning sites (inlets) for 280 sexually mature Common SnookCentropomus undecimalisthrough an array of more than 200 receivers deployed in rivers, estuaries, inlets, and nearshore waters along 320 km of Florida's Atlantic coast. Fish were detected four times as often at and made twice as many trips to a primary spawning inlet than to secondary inlet sites. Fish displayed interannual site fidelity, returning to the primary inlet for as many as five consecutive reproductive seasons. Overall, individuals returned to their primary inlet (return rate [RR] = 0.54) more often than they changed sites between years (straying rate [SR] = 0.29), but variation in RRs and SRs between inlets suggested a spatial effect on interannual site fidelity. During the nonspawning season, fish generally resided less than 40 km to the northwest of their primary inlet. The 95% kernel density estimates (KDEs) for catchment area and dispersal area averaged 220 km2and overlapped greatly for five out of six inlets. The 50% KDE did not overlap between inlets, suggesting that each spawning site had a corresponding winter resident habitat supporting a group of fish that were primarily associated with that inlet. The inclusion of telemetry data in traditional measures of site fidelity allowed for the identification and accurate description of behavioral polymorphism and may be applied to other fish species when spatial substructuring is suspected. Received June 9, 2015; accepted December 3, 2015 [ABSTRACT FROM AUTHOR]

In general, snookCentropomusspp. are opportunistic carnivores, feeding on fish and crustaceans, as shown by other studies on diets of centropomids in the western Atlantic Ocean. Diet studies for centropomids in Florida refer only to a description of the diet and the ontogenetic shifts in prey preferences of Common SnookC. undecimalis. However, no food habit information for Smallscale Fat SnookC.parallelusis available in Florida. Stomach content analysis and quantitative descriptions of fish diet are important in understanding how species utilize resources, coexist in certain habitats, and possibly share available prey. The objective of this study was to describe the dietary composition for Smallscale Fat Snook in east-central Florida, in comparison to other diet studies for Smallscale Fat Snook and its congeners. The results show that, like other snook species, Smallscale Fat Snook is a carnivorous species, juveniles feed mainly on penaeid shrimp, and larger fish feed more on varied prey, mainly portunid crabs and teleost species. The diverse diet composition of Smallscale Fat Snook in east-central Florida suggests that the species is an opportunistic feeder, exploiting locally abundant prey, and feeds in a variety of estuarine and riverine habitats. Received March 18, 2014; accepted April 17, 2014 [ABSTRACT FROM AUTHOR]