September 21, 2024 — A team led by researchers at the University of Washington and the National Oceanic and Atmospheric Administration has uncovered key information about what resident killer whale populations are eating. Researchers had long known that resident killer whales—also known as resident orcas—prefer to hunt fish, particularly salmon. But some populations thrive, while others have struggled. Scientists have long sought to understand the role that diet plays in these divergent fates.
“Killer whales are incredibly intelligent, and learn foraging strategies from their matriarchs, who know where to find the richest prey resources in their regions,” said Amy Van Cise, UW assistant professor of aquatic and fishery sciences, who began this study as a postdoctoral researcher with NOAA’s Northwest Fisheries Science Center. “So we wanted to know: Does all of that social learning affect diet preferences in different populations of resident killer whales, or in pods within populations?”
In a paper published in the journal Royal Society Open Science, Van Cise and her colleagues report the cuisine preferences of two resident killer whale populations: the Alaska residents and the southern residents, which reside primarily in the Salish Sea and off the coast of Washington, Oregon and northern California.