Effects of the 'Amoco Cadiz' Oil Spill on the Seagrass Community at Roscoff with Special Reference to the Benthic lnfauna

Abstract

The benthic fauna of an eelgrass (Zostera marina L.) community was investigated at Roscoff (France) from Oct., 1977-April, 1979. The impact of the Amoco Dadiz oil spill of March, 1978, on the community was studied. Direct effects on the eelgrass itself were only local during the 1st weeks after the spill, when many plants had black, burnt leaves. This was a temporary phenomenon, for the production of new leaf tissue continued normally. Effects on the benthic fauna were observed directly after the arrival of the oil at Roscoff. A sharp decrease in numbers of both individuals and species occurred, mainly caused by an almost total disappearance of the smaller Crustacea and Echinodermata and a serious numerical decrease in other groups. Recovery took place relatively rapidly. In the beginning of 1979 all nubers were at the same level as the year before, the filter feeding Amphipoda being the the only exception: on May 1, 1979, they were still absent.