Occurrence and abundance of the deep-water red shrimps Aristeus antennatus (Risso, 1816) and Aristaeomorpha foliacea (Risso, 1827) in the central eastern Mediterranean Sea

The blue and red shrimp Aristeus antennatus and the giant red shrimp Aristaeomorpha foliacea are among the major economic resources in the Mediterranean Sea and represent the main target of the western and central Mediterranean deep sea (400 800 m) fisheries. In this paper, data on abundance (both density and biomass) of A. antennatus and A. foliacea resulting from the MEDITS surveys from 1994 to 2004, carried out with common protocols in seven Mediterranean FAO GFCM Geographical Sub Areas (GSAs), have been analyzed using standardized methodologies. Both red shrimps species occur almost exclusively on the "meso bathyal" stratum (500 800 m). The distribution pattern appears quite different for the two species, but no significant trends in density and biomass (neither at geographical nor at temporal level) could be detected. Sardinia shows the highest abundance for both species, although with some local negative tendencies along time. A very high interannual variability was detected in all areas. Comparing the present results to those recorded by Cau et al. in 2002, a rather stable status of the deep sea red shrimps stocks was observed, which is not an encouraging finding when considering the reduction in fishing capacity and the management measures adopted by the EU in recent years.