REPRODUCTIVE SUCCESS AND HISTOPATHOLOGY OF INDIVIDUAL PRINCE-WILLIAM SOUND PACIFIC HERRING 3 YEARS AFTER THE EXXON-VALDEZ OIL-SPILL

Adult Pacific herring (Clupea pallasi) collected in 1992 from a site p reviously oiled by the Exxon Valdez oil spill exhibited a lower percen t hatch and produced fewer morphologically normal larvae than fish fro m a previously unoiled site. Possible explanations for these reproduct ive differences include (i) exposure to residual oil, (ii) homing of p reviously oil-injured fish, (iii) homing of different strains of herri ng, and (iv) physical or chemical characteristics of each exposure sit e unrelated to oil. Differences in microscopic tissue lesions were als o observed and were marginally significant between sites. Granulomatou s inflammation occurred only in females from previously oiled sites, a nd this plus increased splenic congestion were negatively correlated t o production of normal larvae. Scores for macrophage aggregates in spl een, liver, and kidney were greater in fish from previously oiled site s, particularly in males, but differences were related to age rather t han exposure history. Because most of the lesions related to reproduct ive success were acute or subacute, differences in tissue damage could not be directly related to previous oil exposure.