The effects of brief exposure to aromatic hydrocarbons on feeding and avoidance behaviour in coho salmon, Oncorhynchus kisutch

Two experiments determined the effects of exposure to aromatic hydrocarbons on feeding and avoidance behaviour in coho salmon, Oncorhynchus kisutch . Subjects received brief exposure to different concentrations of a mixture of seven aromatic hydrocarbons dissolved in acetone and sea water. Exposure to a low concentration decreased feeding. At a higher level, all fish stopped feeding for 3 days and one fish stopped feeding for 10 days. Salmon exposed only to acetone fed normally. Experiment 2 subjects were trained to avoid electric shock. Exposure to a low level of pollutant caused an initial reduction in avoidance response. Exposure to the high level caused a greater reduction and a longer reaction time to the conditioned stimulus. Results suggested that exposure to these levels of aromatic hydrocarbons could limit a fish's ability to survive.