August 3, 2020 — The U.S. Army Corps of Engineers’ final environmental review of Pebble says that under normal operations, it does not expect the mine to have a significant effect on fish populations in Bristol Bay. But the Corps does say the mine would harm fish around the mine site. Some scientists say the project could also put a specific salmon population in the Koktuli River at risk and remove genetic diversity from the region.
The mine would be built at the headwaters of the Koktuli River drainage, and it would eliminate about 20% of available habitat there, though the Corps says that does not necessarily represent fish habitat.
Daniel Schindler has spent decades studying salmon in the Bristol Bay watershed. He’s a professor of fisheries sciences at the University of Washington
“If you looked at the Koktuli all by itself, and you assumed that all sockeye salmon are interchangeable across all of Bristol Bay, then you would say that the Koktuli River is a very small piece of habitat, and it’s not that important,” he said.
According to Schindler, the variety of different life strategies and genetic identities of sockeye throughout Bristol Bay ultimately stabilizes the returns of fish back to the rivers every year.