North Atlantic minke whale (Balaenoptera acutorostrata) feeding habits and migrations evaluated by stable isotope analysis of baleen

Abstract Isotopic analyses of the incrementally growing baleen in Mysticeti have been used to learn about their feeding and movement patterns. Using methods previously applied to Pacific minke whales, stable δ 15 N and δ 13 C isotope values were measured along the baleen plates of male and female minke whales from two locations in the Northeast Atlantic. The sample sizes used in this study are comparable to those previously used in the literature, and, although limited in size, the evidence suggests differences in isotopic signatures between whales caught at different locations. Both the δ 15 N and δ 13 C data suggest whales at the higher latitude site of Svalbard have a narrower diet than the whales from Lofoten/Vesterålen in Norway. Across all whales, the δ 15 N data indicate the whales primarily prey on fish for much of the year, only switching to zooplankton during the spring bloom. The δ 13 C data fail to confirm whether the whales migrate over long distances.