Here in the Pacific Northwest, Chinook salmon get lots of attention. For example, in recent years, a brighter spotlight has shone on the plight of endangered southern resident killer whales and their dependence on Chinook as their main food source.
Chinook are the largest species of Pacific salmon, which is why they're commonly referred to as king salmon. But in terms of both numbers and biomass, Chinook are quite literally one of the smallest fish in the big, big sea we call the North Pacific Ocean.
Covering fish issues in the Columbia Basin, it's easy to forget Chinook don't play a very big role in the big picture. A look at the North Pacific Anadromous Fish Commission's mid-June news release on total salmon catches in 2019 brings this realization home.
The news release announces total salmon catches as reported by the countries who catch them—Canada, Japan, South Korea, Russia and the U.S., which is further broken out into Alaska and the West Coast. The commission notes Pacific salmon abundance remains close to all-time high levels, and last year's total catch of about 968,700 metric tons declined slightly since the record-high catch of about 1.15 million metric tons in 2009. The total commercial catch is about twice as high as it was in the 1950s, 1960s and 1970s.
A few things about the announcement caught my eye. Last year, the West Coast—Washington, Oregon and California—caught the fewest salmon in terms of both weight and number of fish since the commission began keeping records in 1925. Russia and Alaska both caught about a hundred times more fish by weight, and 200 to 300 times more by the number of salmon caught. Compare the West Coast's 4,965 metric tons (1.37 million salmon) to Russia's 499,208 metric tons (334.11 million fish) and Alaska's 401,994 metric tons (208.26 million fish) and you begin to get the picture that commercial fishing here in the Pacific Northwest is a tiny fraction of what it is in Alaska and Russia.
Canada also experienced record-low catches last year—2,973 metric tons (963,000 fish)—which were also the lowest since 1925. South Korea caught the fewest fish, with just 130 metric tons (50,000 fish). Japan ended last year's fishing season in third place with 59,460 metric tons (18.52 million salmon)—far behind Russia or Alaska, but still many times better than the West Coast, Canada or South Korea.
Of the 968,730 metric tons of fish caught commercially in all five countries, pink salmon made up more than half of the weight—525,343 metric tons. Chinook totaled 5,562 metric tons.
The news release also notes that 2019 marked the highest hatchery releases on record. Of the 5.52 billion salmon and steelhead released from hatcheries in the five countries, 1.36 billion were pink salmon and 3.47 billion were chum. Meanwhile, 241 million hatchery releases were Chinook. The vast majority of Chinook hatcheries are in the U.S., with 192 million releases coming from Washington, Oregon, California and Idaho. Canada adds another 38 million, and Alaska pitches in 10 million.
Meanwhile, Alaska released almost a billion pink salmon (934.7 million), Russia added in 283.2 million and Japan contributed 129.6 million.
Now, pink salmon are already the most abundant salmon species in the North Pacific Ocean. Two years ago, research scientists Gregory Ruggerone and James Irvine completed the most comprehensive abundance study of salmon in the North Pacific and found that pink salmon have dominated the numbers since 1990, comprising about 67 percent of the North Pacific's salmon and 48 percent of its biomass. Chum and sockeye also make up significant portions of both numbers and biomass. Chinook, coho and steelhead were not included, as they comprise only about 4 percent of the total catch.
Ruggerone—a former member of the Independent Scientific Review Panel and now a member of NOAA's Hatchery Scientific Review Group—told me that Chinook, coho and steelhead once enjoyed a higher percentage of the overall salmon numbers in the Pacific, but not significantly higher. He believes a surge in abundance of pink, chum and sockeye salmon—aided by the 1977 ocean regime shift and by hatchery production—may be contributing to depressed numbers of other species.
Pink salmon also have a competitive advantage compared to other salmon species. They spend only one year in the ocean, so poor ocean conditions don't impact their life cycle as deeply as salmon that spend significantly more time in the ocean. They also migrate early, so they get to the ocean first, grow quickly and are able to outcompete other first-year salmon for food.
Perhaps more important these days is that pink salmon appear to be thriving in the warmer ocean, while species like Chinook are clearly suffering from the changes.
People who want to help endangered orcas—an iconic Northwest species—have spent a lot of time working on ways to increase Chinook abundance. According to Washington Gov. Jay Inslee's orca task force, about 80 percent of a southern resident orca's diet is Chinook. An adult male needs about 325 pounds of Chinook a day to meet its energy requirements.
That task force put out two reports with dozens of recommendations. I have seen nothing in either report that mentions competition with pink salmon when they reach the ocean.
The question of whether pink salmon are outcompeting Chinook salmon in the ocean is not at all settled. Even if it's true, I am skeptical any single reason is causing the decline in Chinook and steelhead runs. But as the push to address this problem strengthens through the Idaho governor's work group and growing talk of a regional collaborative effort to bring back Snake River salmon and steelhead, perhaps the issue of ocean competition should be part of that discussion.
In my most recent conversation with Ruggerone in June, he joined other scientists in calling for a close examination of hatchery production—not in the Columbia River, but in Alaska and in other countries, where hatcheries are dumping millions of pink salmon.
For decades, scientists who look at the big picture have been calling for international cooperation to consider and possibly limit the number of hatchery salmon released into the ocean.
Seeing the numbers in black and white in the North Pacific Anadromous Fish Commission's report makes me wonder the extent to which pink salmon that are being released by the millions could be impacting salmon and steelhead returns to the Columbia Basin.