Tuesday February 21, 2023
Nature World News —
Not all Chinook salmon are created equal, which has a significant impact on the energy levels of southern resident killer whales.
A recent study quantified the lipid content in Fraser River Chinook salmon, the preferred meal of southern residents, and discovered that spring-run Chinook salmon, the first to arrive in the Salish Sea, is lipid-rich and energy-dense, which is important for the killer whales that prey on them.
Later-season Fraser River Chinook salmon have a lower energy density.
“This research helps us quantify the energetic requirements of the southern residents,” said Jacob Lerner, lead author of the study and a doctoral student at the Institute for Oceans and Fisheries’ Pelagic Ecosystems Lab, as per ScienceDaily.
For example, if southern residents only ate low-lipid salmon, they would have to consume approximately 80,000 more Chinook salmon per year than if they only ate high-lipid salmon.