Nearshore ichthyoplankton associated with seagrass beds in the lower Chesapeake Bay

Estuaries serve as important nursery habitats for larvae and juveniles of many species of fishes and invertebrates. Within the estuary, however, partitioning may occur among main channel, mud flat, tidal creek, and vegetated habitats In this study we describe the egg, larval. and juvenile fish assemblages in shallow areas of submerged aquabc vegetation (SAV) of the lower Chesapeake Bay and compare them with those over the adjacent, shallow sand habitat. Densihes at night over all habitats were about 1 order of magnitude higher than daytime densities, and were highest in summer. The SAV habitats were not important spawning sites for species with pelagic eggs, but were important for species brooding eggs or with demersal eggs. Overall, collections were dominated by the bay anchovy Anchoa mitchilli, but contained many species not commonly found in the midchannel ichthyoplanktan described in earlier studies; these include the croaker Micropogonias undulatus, rough silverside Membras martmica and northern pipefish Syngnathus fuscus. Conversely, the weakfish Cynoscion regalis was rare in our collections as compared to main channel samphng areas. Our results suggest that SAV areas do not play an important nursery role for pelagic eggs and early larvae, whxh may suffer increased predation by planktivores in these areas. Later stages, however, may benefit from reduced predation. pressure from piscivores and thus benefit from association with SAV.