The very precious Alaskan salmon, a favorite of seafood lovers around the world, it is getting smaller and the climate change is a suspected culpritaccording to a new study from the University of Alaska, documenting a trend that may pose a risk to the fishing industry, indigenous peoples and biodiversity.
Scientists at the University of Alaska at Fairbanks (UAF) have found that four of Alaska’s five wild salmon species have been shrinking in average size over the past six decades, and stunting has become more pronounced since 2010.
The hardest hit is the Chinook salmon, also known as king salmon and Alaska’s most popular species. Chinooks are on average 8% smaller than they were before 1990, according to the study, published Wednesday in the journal Nature Communications. Alaska sockeye, coho and chum salmon are also declining, according to the report. The findings are based on data from 12.5 million samples collected over six decades.
Alaskans, with generations of salmon farming tradition, have long noticed the trend. “People walk into their smokehouses and they no longer have to stoop. The fish are smaller,” says Peter Westley of the UAF School of Fisheries and Ocean Sciences and a co-author of the study.
The phenomenon is attributed to rising water temperatures and increased competition among all salmon species are the most likely factors behind the reduction in fish, he said. Salmon mature in the ocean at earlier ages and return to freshwater younger and smaller than in the past, the study found.
In waterways like the Yukon River, famous for its Chinooks, you no longer see the “really big fish” that spend seven or eight years in the ocean, Westley said, but only four-year-olds.
Power in the US
Alaska produces almost all of the wild salmon in the US. Last year, commercial fishermen caught more than 206 million salmon and sold them for $ 657.6 million, according to official figures. Salmon is also a staple food for some indigenous peoples in Alaska and the Canadian Yukon Territory.
Alaskan bears and other wildlife also eat red-fleshed fish. Smaller fish mean fewer nutrients for those animals and fewer salmon eggs, which can have long-term consequences for the wildlife that feed on them, said the UAF’s Krista Oke, lead author of the study.