Distribution of larval fish between macrophyte beds and open channels in a southeastern floodplain swamp

Larval fish assemblages drifting in the open channels and those in adjacent macrophyte beds differed in standing stock and species composition. Standing stocks were approximately 160 times higher in the macrophyte beds than in the open channels during the day but, due to an increase in the number of drifting larvae, only 13 times higher in the macrophyte beds than in the open channels at night. Larvae concentrated in the interior of the macrophyte beds rather than at the ecotone between the macrophyte beds and the open channels. Notropis spp. and Lepomis spp. predominated in the drift while Notropis spp., Elassoma zonatum, Erimyzon succetta, and Lepomis spp. predominated in the macrophyte beds. Drift among all taxa involved only small postlarvae. The drift of Lepomis spp. larvae appeared to be associated with dispersal from the nest at the time of yolk sac depletion.