Analysis of demersal species assemblages from trawl surveys in the South Adriatic sea

Abstract

Two trawl surveys were carried out in the summer months (June–July) of 1996 and 1997 along the whole South Adriatic area (Mediterranean sea) for the first time, using the same vessel and the same sampling gear (European Community Research Project ‘MEDITS’); previous research data referred only to the south-western Adriatic side. A total list of 168 demersal species (fishes, cephalopods and crustaceans) was obtained during the surveys; species abundance data (individuals/trawling hour) were processed according to multivariate techniques in order to describe the composition and the distribution of the main species assemblages within the investigated area (10–800-m bathymetric range). Multivariate analysis of MEDITS survey catch data showed a bold relationship between fish assemblages and depth, while the influence of depth was lower with respect to cephalopod and especially crustacean assemblage distribution.