DIETS OF 2 DEEP-SEA DECAPODS - NEMATOCARCINUS-EXILIS (CARIDEA, NEMATOCARCINIDAE) AND MUNIDA-TENUIMANA (ANOMURA, GALATHEIDAE) ON THE WESTERN MEDITERRANEAN SLOPE

The composition of the diet of the deep-water decapods Nematocarcinus exilis and Munida tenuimana were established in samples obtained between 552-2266 m on the Catalan Sea slope. Both species fed on fish remains and on slow-moving benthic resources (Benthonella tenella, ostracods, pteropod remains, Stephanoscyphus spp.). However, pelagic resources (siphonophores, euphausiids, hyperiid amphipods represented a high proportion of M. tenuimana's diet, but only down to 1200 m. In contrast, siphonophores were the only relatively abundant prey of pelagic origin in the diet of N. exilis. Seasonal changes in the diet, mainly related to the consumption of pelagic prey, were almost exclusively restricted to depths down to 1200 m. Below 1200 m both species exhibited a higher consumption of teleost fish remains, detritus of pelagic decapods, pteropods, and foraminiferans. This increase in detritivorous habits with depth seems to be an adaptation to environments with lower trophic resources.