The demersal fish of Narragansett Bay: An analysis of community structure, distribution and abundance

Abstract

Monthly samples of demersal fish were collected from nine regular and 13 occasional stations in Narragansett Bay, Rhode Island throughout a year. While over 9000 individuals representing 99 species were taken, the 10 most abundant species made up 91% of the catch. Taxonomic composition and dominance of the fish community were generally similar to that reported for adjacent Block Island Sound and Long Island Sound, though diversity was slightly higher in the bay. Winter flounder, Pseudopleuronectes americanus was by far the most abundant species, and accounted for 36% of the total catch. Multiple regression analysis of fish numbers and biomass for total catch and for the dominant flounder indicated that of 14 environmental variables considered, only depth, sediment organic content, temperature and wind speed were significant in explaining distribution within the bay. No clear pattern of fish abundance was apparent, except for higher diversity near the mouth of the bay. The mean annual standing crop of 117 ± 151 fish/acre and 28·5 ± 16·0 lbs/acre (wet weight) was comparable to values reported for a variety of New England coastal and offshore areas. The total biomass of fish remained remarkably constant throughout the year when compared to adjacent coastal environments, while the abundance of particular species varied substantially with season.