ROLE OF FEEDING AND PREY DISTRIBUTION OF SUMMER AND SOUTHERN FLOUNDERIN SELECTION OF ESTUARINE NURSERY HABITATS

Diets of metamorphosing larvae and early juvenile summer and southern flounder were examined during the settlement period when their distrib utions overlapped and during a subsequent period when the two flounder s were found in different habitats. Prey abundance on tidal flats was examined along an upstream transect. Though initially similar, diets o f the two species diverged prior to the development of a segregated di stribution. These diet differences reflected those found in the diets of the two species following segregation. Southern flounder ate more a ctive epifaunal prey: mysids, amphipods and calanoid copepods and appe ared to be an ambush predator. The summer flounder ate primarily infau na: polychaetes, and invertebrate parts and appeared to be an active f orager. Distribution of prey within the study area suggested that mysi d gradients may influence movement of southern flounder to nursery gro unds. The coupling of biotic and abiotic gradients are probably import ant in creating nursery areas and guiding fishes to species specific h abitat types. (C) 1995 The Fisheries Society of the British Isles