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Bristol Bay

About EPA's Bristol Bay Assessment

In January 2014, after three years of rigorous scientific study, EPA released its final assessment The Effects of Large Scale Mining on the Salmon Ecosystems of the Nushagak and Kvichak Rivers.

The key findings of the assessment are:

  • The Bristol Bay watershed supports the largest sockeye salmon run in the world, producing approximately 46% of the world’s wild sockeye harvest.
  • The annual average run of sockeye in the Bristol Bay watershed was approximately 37.5 million fish between 1990 and 2010. In 2009, Bristol Bay’s wild salmon ecosystem generated $480 million in direct annual economic expenditures in the region and sales per year and employed over 14,000 full and part-time workers.
  • All five species of Pacific salmon - sockeye, Chinook, coho, chum and pink - spawn and rear in the Bristol Bay watershed. In addition, the Nushagak River supports one of the world’s largest Chinook salmon runs.
  • The Bristol Bay watershed provides habitat for 29 fish species, more than 190 bird species, and more than 40 terrestrial animals.
  • The Bristol Bay watershed supports large carnivores such as brown bears, bald eagles, and wolves that depend on salmon; ungulates such as moose and caribou; and numerous waterfowl species.

The assessment found that mining the headwaters of these river systems could cause harm to the valuable fishery in Bristol Bay.


Final Assessment

Draft Assessments