Impact of the Oil Spill on Juvenile Pink and Chum Salmon and Their Prey in Critical Nearshore Habitats

The objective of this study was to determine the impact of the Exxon Valdez oil spill on juvenile pink and chum salmon during their initial period of residency in nearshore marine habitats of western Prince William Sound. In oiled locations, both pink and chum salmon fry in the nearshore marine environment were contaminated by hydrocarbons in 1989, but not in 1990. Field observations and laboratory experiments indicated that ingestion of whole oil or oil-contaminated prey was an important route of contamination. In 1989, juvenile pink salmon grew significantly slower and were significantly smaller in oiled locations than non-oiled locations, although neither their feeding nor availability of their prey was reduced in oiled locations. In 1990, size and growth of juvenile pink salmon were similar in oiled and non-oiled locations. We concluded that oil contamination from the Exxon Valdez reduced the growth of juvenile pink salmon in western Prince William in 1989. Because survival of pink salmon is directly related to growth during their early marine residency, survival and productivity of affected salmon populations were probably also reduced.