A comparative study of the macrobenthic infauna of two bathyal Cantabrian Sea areas: The Le Danois Bank and the Avilés Canyon System (S Bay of Biscay)

Multidisciplinary studies were carried out in the Cantabrian Sea (N Spain) to investigate benthic habitats and compare the communities of two areas: the Le Danois Bank in 2003–2008 under the ECOMARG project, and the Avilés Canyon System in 2010–2011 under the INDEMARES (LIFE+) project. The main aim of this publication is to describe the composition and spatial distribution of the benthic fauna inhabiting the sedimentary grounds of these deep-sea areas, as well as the possible relationships with the environmental variables that characterise these habitats.The soft-sediments and infaunal communities of these two deep-sea ecosystems were sampled using a box corer. The granulometric analyses of the sediments showed a grain size gradient decreasing with depth in both areas. Their infaunal communities showed similar numerical abundance patterns, with decreasing values in relation to depth. The highest abundance values were reached below 500 m deep, and the lowest values were found at deeper stations. The infaunal communities of both areas were mainly dominated by polychaetes, followed by peracarid crustaceans and bivalve molluscs.