Ecology of demersal fish from a long-term deep-sea observatory, the AWI-Hausgarten (79°N west off Svalbard)

• Main Authors: Bergmann, Melanie, Klages, Michael
• Format: Conference Object
• Language: unknown
• Published: 2005
• Subjects: Svalbard; Fram Strait
• Online Access: https://epic.awi.de/id/eprint/13088/; https://epic.awi.de/id/eprint/13088/1/Trophic%20ecol%20black.pdf; https://hdl.handle.net/10013/epic.23481

In 1999, the AWI deep-sea research group established the first and only long-term deep-sea observatory beyond the polar circle, the AWI-Hausgarten (Fram Strait, west off Svalbard). It consists of nine regularly sampled stations along a depth gradient from 1200 to 5500m, a latitudinal transect and an experimental area at the centre for long-term experiments. Footage from underwater camera transects has shown that demersal fish which belong largely to the eelpout family constitute an important fraction of the benthic megafauna. Despite their numerical abundance little is known to date about their biology and functional ecological role. First evidence suggests that the abundance of fish decreases with increasing depth while the mean size of fish increases. Samples taken by trawls and baited traps at two stations complement camera observations and facilitated a direct identification of the species present: Lycodes squamiventer dominated at the shallow station (1200m) while Lycodonus flagellicauda, Gaidropsaris argentatus and the ray Raja hyperborea occurred in low numbers. The larger-sized congeneric Lycodes frigidus was most abundant at the central station (2400m), with a few individuals of the rare species Lycenchelys platyrhina. The biology and functional ecological role of these fishes is discussed with particular emphasis on their trophic status.