Structural Components of Eelgrass (Zostera marina) Meadows in the Lower Chesapeake Bay: Fishes

Abstract

The structure of the fish community associated with eelgrass beds in the lower Chesapeake Bay was studied over a 14 month period. A total of 24,182 individuals in 48 species was collected by otter trawl with Leiostomus xanthurus (spot) comprising 63% of the collection, Syngnathus fuscus (northern pipefish) 14%, Anchoa mitchilli (bay anchovy) 9%, and Bairdiella chrysoura (silver perch) 5%. The density and diversity of fishes were higher in vegetated areas compared to unvegetated areas; fishes were more abundant in night collections Fish abundance and species number increased in the spring and early summer as both water temperature and eelgrass biomass increased and decreased in the fall and winter as temperature and eelgrass biomass decreased. Gill netting revealed some of the top predators in the system, especially the sandbar shark, Carcharhinus milberti. The fish community in the Chesapeake Bay was quite different from North Carolina eelgrass fish communities. Most notable was the rarity of the pinfish, Lagodon rhomboides, which may be a very important predator in the structuring of the epifaunal communities.