Page 945 - The Toxicology of Fishes
P. 945

23




                       Effects of the Exxon Valdez Oil Spill on

                       Pacific Herring in Prince William Sound, Alaska






                       Gary D. Marty



                       CONTENTS
                       Background ............................................................................................................................................925
                       Life History and Background................................................................................................................927
                       Post-Spill Damage Assessment .............................................................................................................927
                           Measurements of Potential for Exposure ....................................................................................928
                           Measurements of Actual Exposure ..............................................................................................928
                           The Effects of Exposure...............................................................................................................928
                       Summary ................................................................................................................................................930
                       Acknowledgments..................................................................................................................................931
                       References..............................................................................................................................................931



                       Background*
                       On March 24, 1989, the Exxon Valdez ran aground on Bligh Reef in the northeastern part of Prince
                                                           6
                       William Sound (PWS), spilling about 40 × 10  L of crude oil. This was the largest crude oil spill in
                       U.S. waters, and it occurred in what otherwise was a relatively pristine, highly productive, but highly
                       sensitive ecosystem. After three days of calm weather and smooth seas, strong northeasterly winds arose
                       and dispersed the oil beyond any hope of containment. The spilled oil, soon in the form of thin sheens
                       and thick mousse, continued to spread to the southwest (Short and Harris, 1996). Control was difficult
                       due to variable weather conditions and tide cycles that ranged up to 6 m. The oil came ashore along an
                       approximately 750-km trajectory from PWS to the southern Kodiak Archipelago and Alaska Peninsula.
                       The distribution and depth of the oil along the shoreline were discontinuous and variable, both on the
                       surface and within the beach substrate. Estimates vary, but about 20% of the spilled oil evaporated, 40%
                       was deposited on beaches within PWS, and about 10% entered the Gulf of Alaska (Spies et al., 1996).
                       By fall 1992, only about 2% of the spilled oil remained on the beaches (Spies et al., 1996). Field surveys
                       conducted in the summer of 1989 identified 720 km of oiled shoreline within PWS, over 300 km of
                       which was classified as heavily oiled.
                        Work after the spill was divided into three phases: response, damage assessment, and restoration.
                       Management of response was an effort coordinated by the U.S. Coast Guard, the Alaska Department of
                       Environmental Conservation, and Exxon, but other federal and state agencies and local communities
                       played key roles. Both damage assessment and restoration activities were managed by the State of Alaska
                       and three federal agencies acting together as Natural Resource Trustees as provided by the Comprehensive


                       * Ecosystem-level impacts of the spill are reviewed elsewhere (Peterson et al., 2003). The background information in this
                       section is adapted with permission (public domain) from the website of the Exxon Valdez Oil Spill Restoration Office
                       (http://www.evostc.state.ak.us/).


                                                                                                   925
   940   941   942   943   944   945   946   947   948   949   950