| Summary: | Study History: A comprehensive assessment of coastal habitat was initiated as Coastal Habitat Study No. 1 in 1989 following the Exxon Valdez oil spill. In 1990, experimental studies began in Herring Bay, Knight Island, Prince William Sound, which were designed to compliment the overall monitoring program by experimentally assessing intertidal community dynamics and mechanisms of recovery. This experimental approach went beyond basic species inventories, allowing a more comprehensive assessment of the oil spill impacts on physical and biological interactions mediating community structure. The manipulative experiments were designed to evaluate the strength of important species interactions and the role of physical factors in community structure. Abstract: Intertidal studies established in 1990 in Herring Bay, Prince William Sound in response to the Exxon Valdez oil spill continued through the 1995 field season. Examination of the dominant intertidal alga, Fucus gardneri, showed that in the high intertidal, reproductive plants had fewer receptacles per plant and egg settlement rates were lower at oiled than control sites. Fucus germlings were negatively affected by herbivores and desiccation. Excluding plants which lost thallus material, plants grew faster at oiled than control sites. Experiments employing biodegradable erosion control fabric mats to act as a substrate for Fucus germlings were initiated in 1993 on a sheltered rocky site which had been heavily oiled. Dense populations of Fucus had developed on the surface of the mats by the summer 1994. Populations of intertidal grazing invertebrates, such as limpets and periwinkles continued to show reduced densities on oiled sites in 1994. Results of comparisons of mussel size-frequency, filamentous algae abundance and mussel recruitment in filamentous algae on oiled and control sites showed a higher abundance of smaller and recruiting mussels and filamentous algae on oiled sites. These patterns appear to be related to the detection of higher water motion on oiled sites based on calcium sulphate cylinder dissolution rates. Publications: Highsmith, R.C., M.S. Stekoll, P.G. van Tamelen, S.M. Saupe, T.L. Rucker and L. Deysher. 1995. Herring Bay experimental and monitoring studies, Exxon Valdez Oil Spill Restoration Project Annual Report (Restoration Project 94086), Alaska Department of Fish and Game, Habitat and Restoration Division, Anchorage, Alaska.
|
|---|