Passive acoustic monitoring of killer whales in the northern Gulf of Alaska

Original provider:
Hannah Myers

Dataset credits:
Hannah Myers, University of Alaska Fairbanks

Abstract:
Killer whales (Orcinus orca) are top predators throughout the world’s oceans. In the
North Pacific, the species is divided into three ecotypes—resident (fish-eating),
transient (mammal-eating), and offshore (largely shark-eating)—that are genetically
and acoustically distinct and have unique roles in the marine ecosystem. We deployed
hydrophones in the northern Gulf of Alaska to examine the year-round distribution of
killer whales from 2016 to 2020 using passive acoustic monitoring. Highest year-round
acoustic presence occurred in Montague Strait, with strong seasonal patterns in
Hinchinbrook Entrance and Resurrection Bay. Passive acoustic monitoring revealed
that both resident and transient killer whales used these areas much more extensively
than previously known and provided novel insights into high use locations and times
for each population. These results may be driven by seasonal foraging opportunities
and social factors, and have management implications for this species.