THE WORLD-PRODIGY OIL-SPILL IN NARRAGANSETT BAY, RHODE-ISLAND - ACUTEEFFECTS ON MACROBENTHIC CRUSTACEAN POPULATIONS

On June 26, 1989, the tanker 'World Prodigy' ran aground just outside the mouth of the West Passage of Narragansett Bay, Rhode Island, USA. About 922 metric tons of No. 2 fuel oil were released into the water a nd drifted over a total area of about 120 sq miles. Three days after t he spill only a small fraction of the oil remained. The effects on mac robenthic crustaceans within the first five weeks after the spill were studied at five stations with a varying degree of oil exposure, inclu ding one control site never reached by oil from the spill. Significant differencies between these stations were noted for total amphipod abu ndance, the amphipod genus Ampelisca and ostracods (retained on a 0.3 mm mesh), but not for amphipods of the genus Corophium. At the most he avily impacted station (23 mu g oil g(-1) sediment dry weight), the to tal amphipod abundance, dominated by Ampelisca verrilli, decreased by 86% within the first two weeks after the spill. Decreases in total amp hipod abundance significantly larger than at the control site were not ed also at two other stations, one of which with only trace amounts of oil detected in the sediment. The amphipod populations at these sites were dominated by juvenile specimens. These findings confirm the extr eme sensitivity to oil pollution of amphipods and ostracods, noted in earlier field and experimental studies.