southern resident killer whales

The Southern Resident killer whale (SRKW) population is made up of J-, K-, and L-Pods. They are widely considered the most studied population of cetaceans on the planet, and decades of research means we know them as individuals with traceable matrilineal histories. The official population census of the Southern Residents is conducted annually by the Center for Whale Research. In addition to recording births and deaths, the Center assigns alphanumeric designations and maintains ID catalogs for the Southern Residents.

The Southern Resident population was hit hard by the live capture era of the 1960s and 1970s when orcas were removed from the wild for display in marine aquaria. Several dozen members were either taken or killed during this time. While other orca populations have recovered or increased in the post-capture era, the Southern Residents have not.

They are exclusively fish-eaters with a strong preference for Chinook salmon, and a plethora of issues from over-fishing and dams to fish farms and climate change have impacted the prey sources they depend on.

Js, Ks, and Ls used to be a near-daily presence around the San Juan Islands during the summer months. They’ve shifted their historic travel patterns in response to their declining prey resources, and their search for food is further compounded by the toxic contaminants they carry in their blubber and the anthropogenic noise from vessel traffic and other sources that can mask their echolocation and communication.

Their population currently hovers around 75 individuals and has continued to decline since their endangered listing in the US in 2005.

OBI's research on the Southern Residents focuses on presence/absence in the Salish Sea, behavioral budget and behavioral shifts over time, and acoustic communication.

Days Present in the Salish Sea in 2019-2023

At the Orca Behavior Institute, we track the Salish Sea habitat usage of Southern Resident killer whales to help document changing trends in their habitat usage. The Southern Residents used to spend the majority of May through September in inland waters, but recently have found a “new normal”, where they are mostly absent in the months of April through August, visiting more in September through March. Their fall presence remains high in part because they can take advantage of the fall and winter chum runs in Puget Sound that have fared better than the Fraser River Chinook runs they typically relied on in the spring and summer. When not in inland waters, all three pods spend time on the outer coast, with Js staying primarily in BC waters while Ks and Ls spend a lot of time off the Washington and Oregon coasts with periodic visits to California.

Discover J-, K-, and L-Pod sub-groups