HABITAT-SPECIFIC RECOVERY OF SHALLOW SUBTIDAL COMMUNITIES FOLLOWING THEEXXON VALDEZOIL SPILL

Abstract

We contrasted impacts of the Exxon Valdez oil spill within kelp and eelgrass communities and examined recovery of these communities over a period of up to 10 yr after the spill. Impacts were greatest in sheltered bays that were subject to heavy oiling. The effects of oiling and associated cleanup activities on nearshore subtidal communities within these bays were more evident in eelgrass than in kelp habitats. In 1990, a year after the spill, concentrations of total polycyclic aromatic hydrocarbons (TPAHs) were higher, more groups of organisms were impacted, and more groups showed a negative response to oil (i.e., lower densities at oiled vs. reference sites) in eelgrass than in kelp beds. Recovery was slower in eelgrass than in kelp habitats. About 80% of the groups impacted in eelgrass beds failed to show clear signs of recovery by 1995, six years after the spill. In contrast, most impacted groups in kelp beds recovered within two years. The stronger, more persistent impacts in eelgrass beds were probab...