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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.


Documents

Final Assessment

  • Bristol Bay Assessment - Final Report (January 2014)

Draft Assessments

  • Bristol Bay Assessment - Revised Draft (April 2013)
  • Bristol Bay Assessment - Draft (May 2012)

Related Information

  • Why we studied the Bristol Bay watershed
  • Public involvement for Bristol Bay Assessment
  • Peer review for Bristol Bay Assessment

Bristol Bay

  • Timeline
  • Bristol Bay Assessment
  • About Bristol Bay
Contact Us about Bristol Bay
Contact Us about Bristol Bay to ask a question, provide feedback, or report a problem.
Last updated on August 9, 2024
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