Use and selection of prey by harp seals during summer in the northern Barents Sea

Abstract

The aim of this study was analyse harp seals prey use and selection during summer in Svalbard waters. A total of 41, 34 and 58 (including 24 faeces samples) from animals were sampled in 1996, 1997 and 2004. Krill was the overall dominant prey species (63%) followed by polar cod (16%) and other fish species (10%) in terms of a combined index (frequency occurrence and weight). Resource mapping was performed in two areas simultaneous with the seal sampling, in 1996 and 1997 by using standard acoustic methods. These surveys suggested that krill was the most abundant prey in both areas and years; krill constituted 84% and 69% of the total prey biomass in 1996 (99.7 tonnes/nm2) and 1997 (21.4 tonnes/nm2), respectively followed by parathmisto sp. (13 and 18%) and Gammarus sp. (2 and 12%). The prey preference results suggest that harp seals are not particular prey selective, i.e., harp seals display a random feeding behaviour.