A photographic survey was carried out during the expedition ARK-XXVII/3 to the Nansen and Amundsen basins. The seafloor was photographed using a towed Ocean Floor Observation System (OFOS). Nine transects were performed: four in the Nansen Basin between 83-84°N and 18-110°E at depths 3571-4066 m, and five in the Amundsen Basin between 83-89°N and 56-131°E at depths 4041-4384 m. All images were analysed and stored using the image analysis program and database BIIGLE (BIIGLE.de). Visible megafauna was identified to the lowest possible taxonomic level. Taxonomic identifications were made with the assistance of zoological experts. The following taxa/organisms were excluded from statistical analyses: infauna represented only by surface traces, gelatinous zooplankton, small-size organisms (< 1 cm) and organisms that could not be identified at least to the phylum level. Frequency of occurrence at transects of different taxa was evaluated. Agassiz trawls were taken next to the photographic transects to obtain specimens for verification of taxonomic identifications based on images. In areas of stations 8 and 9 the thick ice prevented trawling operations.

Frequency of occurrence at transect:0 – no occurrence1 – met less than ten images (for transects 7 and 9: 1 - met less than five images)2 – met from ten to quarter of images3 – met from quarter to half of images4 - met from half to three-quarter of images5 – met from three-quarter to all images6 – species occurred at trawl samples.