Last summer, across southwest Alaska’s Bristol Bay region—home to the largest sockeye salmon fishery in the world—tens of thousands of fish washed up dead along riverbanks. Rivers running at temperatures above the threshold for salmon health were killing the fish even as record numbers of them were returning from the ocean to reproduce.
On the Ugashik River, a wide, muddy tributary of the bay, salmon schooled near the river’s mouth, hunkered down in the deeper, cooler water, but they refused to swim upstream into the too-warm waterway. Because no salmon were reaching spawning grounds upriver, the state closed commercial fishing on the Ugashik in early July, right at the normal peak of the run.
Unable to wet their nets and unsure when the fishery would reopen, Ugashik fishermen bided their time at seasonal camps,