Variability in growth rates of juvenile fishes in different estuarine habitats

Abstract

Conducted caging experiments with Pseudopleuronectes americanus, Tautoga onitis and Gobiosoma bosci in New Jersey. Two sites were in an estuary with dense eelgrass Zostera marina beds (Little Egg Harbor) and two were in an estuary lacking eelgrass but supporting patchy accumulations of the macroalgae Ulva lactuca (Great Bay). For all three species, growth was highest at a Great Bay site and generally lowest at a Little Egg Harbor site. The presence of vegetation (either Zostera or Ulva) was beneficial to growth only for T. onitis. Observed patterns in water temperature, sediment structure, and food availability were potential factors effecting the observed differences in growth rates. P. americanus and T. onitis were more abundant in areas supporting faster growth, but the complete absence of tautog from unvegetated substrates suggested some degree of habitat avoidance. A clear trade-off between habitat selection and foraging quality occurred for G. bosci; gobies were most abundant inside eelgrass beds, which supported the poorest growth rates. -from Author