Weak trophic interactions between large predatory fishes and herpetofauna in the channelized Kissimmee River, Florida, USA

We tested the hypothesis that large predatory fishes are major predators of amphibians and reptiles along littoral ecotones by examining the diets of 70 bowfin (Amia calva), 22 chain pickerel (Esox niger), 235 Florida gar (Le pisosteus platyrinchus), 258 largemouth bass (Micropterus salmoides), and 4 6 warmouth (Lepomis gulosus) collected from enhanced and non-enhanced porti ons of the channelized Kissimmee River, Florida, USA. Only six bowfin (9%) and four bass (2%) preyed upon herpetofauna. The diet of bowfin included pe ninsula newts (Notopthalmus viridescens piaropicola), greater sirens (Siren lacertina), and striped crayfish snakes (Regina alleni), whereas the diet of largemouth bass included peninsula newts, striped crayfish snakes, and s tinkpot turtles (Kinosternum odoratus). No individual predator consumed mor e than one type of herpetofauna. The higher percentage of herpetofauna cons umed by bowfin reflects this species' catholic feeding habits. Prey size wa s positively correlated with predator size. Eighty percent of fishes that p reyed upon herpetofauna were collected from non-enhanced portions of the ri ver, which may reflect lower abundance of preferred prey in these disturbed habitats. Overall, it does not appear that amphibians and reptiles are an important part of the piscine food web in the channelized Kissimmee River.