Identifying prey items from New Zealand fur seal (Arctocephalus forsteri) faeces using massive parallel sequencing

The New Zealand fur seal (Arctocephalus forsteri) is one of many pinniped species that has shown a remarkable recovery from the brink of extinction after cessation of commercial sealing during the eighteenth and nineteenth centuries. It is commonly believed that this species competes with recreational and commercial fisheries. We identified prey items using massive parallel sequencing from New Zealand fur seal faecal samples that were collected throughout the species distribution. The data support generalist feeding behaviour for this species. The diet composition showed significant geographical and inter-seasonal variation. As many as 46 species of fish and 18 species of cephalopod were identified from a single colony. The data suggest cartilaginous species (sharks, rays, and skates) constitute an important part of the New Zealand fur seal diet. Approximately 10 % of the species identified in the seal diet were of significant commercial value, which indicates some qualitative food competition between New Zealand fur seals and commercial fisheries in exploiting marine species.