Diet of harbour seals in a salmon estuary in North-West Iceland

Abstract

The effect of harbour seal predation on salmonids has been frequently debated, although interactions between these species have never been thoroughly investigated in Icelandic waters prior to this study. We investigated the diet of harbour seals in a salmon estuary in NW Iceland between 2009 and 2011, using hard part analysis from collected faeces. No evidence of seal predation on salmonids was found in the study. The reconstructed weight and estimated energy content of prey species showed that flatfish was the most important species group, followed by Ammodytidae. The species group found in the highest proportion of samples during the three years combined was also Ammodytidae (45% of the samples). Ammodytidae, flatfishes and capelin dominated by numerical occurrences. However, inter- and intra-annual variation was found regarding the diet.