Niche Partitioning Among Snook (Pisces: Centropomidae) in Rivers of Southeastern Florida and Implications for Species Range Limits

摘要: The presence of relatively rare species in estuarine fish communities can influence niche differentiation among species, functional redundancy, and ecosystem stability when faced with environmental disturbance. In southeastern Florida, at least four snook (Centropomidae) occur coastal river systems, but only one occurs elsewhere the state. To better understand how these co-occur, we analyzed data from electrofishing diet studies conducted during 2007–2010 to investigate partitioning between two species: Common Snook Centropomus undecimalis Smallscale Fat parallelus (common fat hereafter). Although diets collected rivers were barely distinguishable, there was separation habitat use. Adult had affinities for low salinity portions rivers, while common distributed more widely. Use nursery by occurred early spring, confirming winter spawning, which contrasts protracted spawning that spring through fall. While riverine nurseries, juvenile occupied shallow moderate depths cover (e.g., woody debris, docks); greater affinity natural shorelines mangroves, aquatic macrophytes). Overall, appeared occupy niches left open generalist snook. Considering centropomids are likely expand their range northward Florida climate change, understanding use may help predict is first what types will be occupied.