Emily Chan
A team of researchers from the University of Washington and the National Oceanic Atmospheric Administration has uncovered more information about what resident killer whales or orcas are eating. It has long been known that they like to hunt fish, particularly salmon.
However, some populations of resident killer whales are thriving, and others are struggling to survive. So, the researchers want to learn more about the role that diet plays in their survival.
“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, an assistant professor of aquatic and fishery sciences at the University of Washington. ”
‘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?”
The team studied the cuisine preferences of two resident killer whale populations—the Alaska residents and the southern residents, which live in the Salish Sea and off the coasts of Washington, Oregon, and northern California.
Both populations had a tendency to favor salmon, especially Chinook, chum, and coho. But they showed differences when it came to hunting.
They ate different salmon species at certain times of the year and pursued other fish species to supplement their diets.
The study will aid conservation efforts for southern resident killer whales from northern California to the Gulf of Alaska. They are critically endangered, while other populations are increasing in size.
“We know that lack of food is one of the main threats facing the endangered southern resident killer whales,” Van Cise said.
Sign up for Chip Chick’s newsletter and get stories like this delivered to your inbox.
