Vocal behaviour and feeding ecology of killer whales Orcinus orca around Shetland, UK

摘要: Killer whales Orcinus orca are sighted regularly off Shetland, UK, but little is known about their numbers, diet and population identity. We aimed to relate vocal behaviour of killer around Shetland in order investigate structure differences feeding strategies. Fieldwork was conducted the summers 2008 2009. located through a sightings network shore-based scans collected photo-ID data, behavioural information, data acoustic recordings from small boat. The majority encounters (n = 14) were groups (1 15 individuals) travelling close shore on marine mammals. Two with large (20+ herring Clupea harengus farther offshore. Seal-hunting vocalised rarely, producing pulsed calls, echolocation clicks whistles almost exclusively when surface-active or milling after kill. Herring-eating largely silent during one encounter, very other. Analysis calls identified 6 stereotyped call types for seal-hunting 7 herring-eating groups. No shared between both kinds showed striking parallels that Pacific mammal specialists presumably evolved decrease detection by acoustically sensitive prey. One type produced matched vocalisation previous study had described Iceland as possible herding may function concentrate feeding. These findings point dietary specialisation among whales, which should be taken into account making management decisions affecting these animals.