Feeding ecology and foraging behaviour of Arnoux's beaked whale Berardius arnuxii (Duvernoy, 1851) during the period of industrial whaling in Antarctica

Arnoux's beaked whale Berardius arnuxii is the largest and elusive species of family Ziphiidae in the Southern Hemisphere, and data on its foraging ecology is limited. We present bulk bone collagen δ¹³C and δ¹⁵N data for five whales from Deception Island and the Falkland Islands opportunistically collected during the industrial-scale whaling in 1920s-1930s. Compared to scarce published data, isotopic signatures of these specimens demonstrate similarity with South Atlantic and high dissimilarity with New Zealand. By applying Bayesian mixing model analyses to stable isotope data, we attempt to provide retrospective identification of the potential prey items of B. arnuxii in the studied region.