First assessment of the field ecology of larval Atlantic silverside (Menidia menidia)

Abstract

Abstract-The Atlantic silverside (Menidia menidia) is extremely abundant in estuaries in eastern North America, is a significant component of food webs, and is the subject of many laboratory studies; however, the ecology of the larvae of this species in estuaries is poorly known. Using 4 simple collecting gears, we sampled Atlantic silverside larvae in 2 estuaries in Rhode Island that differ in anthropogenic inputs, Pettaquamscutt River estuary and Point Judith Pond, to assess the distribution and abundance of larvae of this species. These larvae occur predominantly in waters less than 1 m deep and are patchily distributed. Larvae collected at depths of 0.2-0.6 m were significantly shorter than those collected at depths of 0.6-0.8 m-a difference in mean total length of ~2 mm. We also compared diets and growth rates of larvae in the 2 estuaries, using gut content analysis and otolith analysis, respectively. Copepod eggs made up 76% of the diet of larval Atlantic silverside in Pettaquamscutt River, whereas copepod nauplii made up 73% of their diet in Point Judith Pond. Growth rates of the larvae did not differ between estuaries.