An underwater image captured in 2016 shows sockeye salmon swimming up the Brooks River in Alaska's Katmai National Park to spawn. The U.S. Department of Agriculture is buying about 50 million pounds of Alaska fish -- pollock, pink salmon and sockeye salmon -- to use in its food and nutrition-assistance programs. (Photo courtesy the National Park Service)
An underwater image captured in 2016 shows sockeye salmon swimming up the Brooks River in Alaska’s Katmai National Park to spawn. The U.S. Department of Agriculture is buying about 50 million pounds of Alaska fish — pollock, pink salmon and sockeye salmon — to use in its food and nutrition-assistance programs. (Photo courtesy the National Park Service)

The U.S. Department of Agriculture will purchase about 50 million pounds of Alaska seafood to use in national…