In 1991, the Endangered Species Committee of the American Fisheries Society (AFS) published an article reviewing the status of Pacific Salmon stocks from California, Oregon, Idaho and Washington in Fisheries magazine(1). The article was later corroborated independently by the National Research Council(2). The AFS committee found that:

• More than 75% of Pacific salmon populations were severely depleted and at some risk of extinction;
• Eighteen of the 214 stocks reviewed appeared to be extinct; 101 were found to be at high risk of extinction; and
• Salmon had disappeared from more than 40% of their historic range.

Consistent with its responsibility under the Endangered Species Act, these findings led the National Marine Fisheries Service (NMFS) to initiate a coast-wide assessment of sea-going salmon and trout in 1992. In Puget Sound, NMFS has focused its concerns on coho and chinook populations and on chum populations in Hood Canal. Virtually all Puget Sound populations of chinook salmon are far below what are believed to be their historic numbers; most have declined from 18% to more than 90% since the 1960s. NMFS has determined that for chinook - and possibly coho - the populations that inhabit the various rivers of the Sound are genetically related and thus share a common destiny; for chum, two population segments in Hood canal are closely related. Such related populations are termed Evolutionarily Significant Units (ESUs) and are the biological unit for listing salmon species under the ESA.

NMFS listed Puget Sound chinook and Hood Canal chum as threatened species under the ESA in 1999, and the U.S. Fish and Wildlife Service listed bull trout as threatened in 1999. Coho are expected to be proposed for listing by the year 2000. The Evolutionarily Significant Unit (ESU) for Puget Sound chinook includes stocks from all rivers in Puget Sound and Hood Canal, including the Elwha and Dungeness Rivers on the Strait of Juan de Fuca.

In 1992, the Washington Department of Fish and Wildlife conducted a status survey of salmon and steelhead in Washington waters. Published in 1993, the Salmon and Steelhead Stock Inventory (SASSI) reviewed 148 stocks in Puget Sound. The review found 11 stocks that were "critical" — that is, subject to permanent harm or extinction; these included stocks of Chinook, chum and steelhead. It found 44 that were "depressed" — that is, whose production was below expected levels; these included stocks of coho and, in Hood Canal, pink salmon. It found 93 stocks to be "healthy" — though even these did not distinguish between fish of hatchery or natural origin, only that they returned to spawn in the wild.