The effect of inherited contamination on egg and larval winter flounder, Pseudopleuronectes americanus

Abstract

The exposure of adult winter flounder, Pseudopleuronectes americanus, to contaminated estuarine environments and a possible impact of this exposure on their progeny was investigated. Polluted study areas included Gaspee Point in upper Narragansett Bay, RI, New Bedford Harbor in Buzzards Bay, MA, noted for its PCB contamination, and Apponagansett Bay, MA, a less contaminated site near New Bedford. Fox Island, a relatively clean area in lower Narragansett Bay, served as a reference area. Although adult winter flounder disperse offshore during the summer, a tag and recapture study verified their yearly residence and exposure to contaminants at Gaspee Point during the spawning season. A similar migratory pattern was assumed for Buzzards Bay fish. Growth, survival and contaminant residues were measured in the progeny of fish collected from the study areas. Eggs from New Bedford Harbor flounder contained significantly higher levels of PCB (39·6 μm−1 dry weight), and larvae which hatched from these eggs, under clean laboratory conditions, were significantly smaller in length (2·96 mm) and weight (0·018 mm) than those from Fox Island fish (1·08 μm PCBg−1 dry weight, 3·22 mm, 0·022 mg). Linear regression analysis indicated a significant inverse relationship between PCB content of the eggs and length or weight at hatch. The adverse ecological consequence of small size at hatch is discussed.