Orcas & Salmon

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Killer whales are still considered one species wherever you find them around the globe, but in reality there are distinct populations throughout the world that are specialized to feed on whatever prey is available to them.

In the Pacific Northwest, we have three such “ecotypes” that don’t interact or interbreed with one another: shark-eating offshores, marine mammal-eating transients, and fish-eating residents. One population of resident killer whales, known as the Southern Residents, frequent the inland waters of Washington State and British Columbia (an area known as the Salish Sea during the summer months (May-September). The Southern Residents were listed as endangered in both Canada (2001) and the United States (2005), with three main risk factors identified: prey availability, toxins, and vessel effects.

Threats to Wild Orcas

A study conducted by the Northwest Fisheries Science Center from 2004-2008 focused on the summer diet of Southern Residents. They collected scale samples from predation events as well as fecal samples that allowed them to determine what the whales had been eating. Using a newly developed coast-wide genetic database for salmon stocks from individual streams and rivers, they were able to determine that 80-90% of the Chinook salmon the Southern Residents consumed in inland waters were from the Fraser River or its tributaries. With headwaters in central British Columbia, the Fraser River flows over 800 miles to its output into the Strait of Georgia near the city of Vancouver. It is one of the largest salmon producing rivers in the world, but the salmon stocks that return to this river are only a fraction of their historical numbers. Similarly, the salmon of the Columbia and Sacramento Rivers, which are likely candidates for producing the salmon stocks the Southern Residents are feeding on during the winter months, have also been severely depleted.

The fish-eating Southern Resident killer whales eat almost exclusively salmon, and during the summer months (May-September) preferentially feed specifically Chinook salmon – this one species makes up more than 90% of their summer diet. The largest and fattiest of the six local salmonid species, Chinook likely provide the whales with the “most bang for their buck” when hunting. At different times of year, the whales will also consume steelhead, chum, and coho, but prey studies have shown they rarely eat sockeye and almost never eat the smallest of the bunch, pink salmon. A little less is known both about where the whales are and what they’re eating during the winter months, but in recent years more information is emerging. It shows the whales are traveling from October-April in the Pacific Ocean from British Columbia to central California, and they are still eating salmon. While other species play a somewhat larger role than during the summer, Chinook is still the predominant prey item.

“80-90% of the Chinook salmon the Southern Residents consumed in inland waters were from the Fraser River or its tributaries.”

In recent years, we’ve been seeing some differences in behavior among the Southern Residents. The three pods (J-, K-, and L-Pods) that make up the community have been splitting up, traveling in much smaller groups than previously. The whales are also spending less time in inland waters. During 2013, which was an especially low Chinook salmon year for the Fraser River, the whales were scarce in inland waters over the summer months, when usually they can be seen on an almost daily basis somewhere in the region. Additionally, as spring Fraser runs have declined since 2007, the whales have shifted to spending hardly any time here in the months of April and May.

The issues that plague our major salmon-producing rivers include dams that block salmon from their natal spawning grounds, historical and current overfishing that have kept healthy numbers of adult salmon from spawning, habitat degradation that has made streams unhealthy places for juvenile salmon, and fish farming – salmon feedlots that wild salmon swim through that are hotbeds of disease.

It’s not uncommon to read about “record” salmon returns to some of our regional rivers, but it’s important to keep these reports in perspective. Salmon numbers seem especially subject to a phenomenon known as “shifting baselines”, where numbers are compared to more recent reference points rather than to even earlier data. For salmon returns, this means we may experience a high return compared to any other return in the last 20 years, but it’s important to remember that even 40 years ago salmon numbers were down drastically from historic numbers. These historic numbers often aren’t referenced in the media, making it seem like things are going just fine for our rivers, when in fact they’re still producing only a fraction of the salmon that they used to.

Salmon live an amazing life cycle that takes them from freshwater streams, where they hatch, down river corridors and through estuaries where they grow, and out saltwater straits into the open ocean where they spend 2-4 years becoming adults before reversing the whole cycle and returning to the same place from which they were born to spawn. Think of the salmon’s life cycle as taking them through a chain of habitats, and like any chain, it is only as strong as its weakest link. If there is a problem in the streams, in the estuaries, in the nearshore coastal waters, or out in the open ocean, the salmon will be effected and will not thrive.

More than 100 species, including humans, consume salmon. Additionally, ocean nutrients are transferred to our forests through spawned out salmon carcasses, further demonstrating how salmon are truly the lifeblood of our Pacific Northwest ecosystems. While it is a worthy cause to protect the salmon and the orcas for their own sake, the local killer whales also serve as an indicator species for the health of our whole region. If they aren’t healthy, neither is our ecosystem, and that is an even greater cause for concern.

What you can do to make a difference

By now I’m sure you’ve realized that there is no simple solution. Salmon recovery in the Salish Sea involves two countries, numerous levels of national, state/provincial, and local government agencies, as well as varied private interests ranging from farmers and loggers to fisherman and real estate developers. It’s going to take all of us pulling in the same direction to restore regional salmon runs, but you can help by doing your part.

  •  Only eat sustainable seafood

    Some fisheries are overfished, while others are well managed. Make sure you’re an educated consumer by referencing the SeaFood Watch Cards put out by the Monterey Bay Aquarium. These guides recommend best choices, good alternatives, and types of fish to avoid based on sustainable management practices and healthy fisheries. If seafood isn’t labeled, don’t be afraid to ask at a restaurant or grocery store where an item came from. Businesses will only change their practices if they realize their consumers will only buy seafood from sustainable sources.

  • Get involved with local salmon habitat restoration

    We can all get involved in helping to preserve and restore our neighborhood streams and rivers. Throughout Washington State there are lead entities for each major watershed that develop and implement local salmon recovery plans. Read more about this community-based salmon recovery effort and find contact information for your lead entity. 

  • Support dam removal

    In September 2011, the largest dam removal project in United States history began along the Elwha River. With largely pristine headwaters within the boundaries of Olympic National Park, the Elwha River will be free-flowing for the first time in over a hundred years. Salmon have already started returning, and biologists estimate the run size could grow from about 3000 fish during the dammed era to as many as 400,000 fish. For a long time, all we had was reasons why dam removal wouldn’t work. Now, we have a success story in the Elwha River, but our job is not done here. Many organizations such as Save Our Wild Salmon agree that the four dams on the lower Snake River should be the next to go. Learn more about this issue by watching the film DamNation. Their website also contains information about how you can take action.

  • Vote for politicians that support wild salmon recovery

    A lot of environmental policy is decided by the government, so we need to make sure we put people in office who support the recovery of wild salmon. The League of Conservation Voters is a great resource to see where candidates stand on environmental issues. See how your local incumbants have scored on recent votes.

  • Donate to the Salish Sea Marine Survival Project

    Despite habitat recovery efforts, reduced harvest rates, and extensive management, we are continuing to see low returns to Salish Sea salmon rivers. We are getting much lower survival among juvenile fish that enter the marine environment in the Salish Sea compared to on the outer coast, indicating that something is happening to effect their survival as they pass through inland waters. We just don’t know what. Long Live the Kings is helping to coordinate a transboundary effort of more than 40 organizations to fund research to figure out what exactly is going on so we can target recovery efforts appropriately. About 60% of the 20 million dollar budget has been raised, but there is still a ways to go. Learn more about the project and donate what you can.

by Monika Wieland

illustrations by Michael Hays
photos by Center for Whale Research

Read This

Salmon biologist Jim Lichatowich does an outstanding job of explaining why regional salmon have declined, how salmon recovery has been mismanaged, and why hatchery fish are not the answer in his 2013 book “Salmon, People, Place: A Biologist’s Search for Salmon Recovery”.

Restore Habitat

Take part in salmon habitat restoration. Organizations like Whale Scout plan volunteer days to restore salmon bearing streams.

Orca Salmon Alliance

The Orca Salmon Alliance (OSA) works to highlight the connection between two iconic endangered species that need help.
Learn more.