Because artificial propagation of Pacific salmonids has been widespread for many years, the influence of hatchery fish needs to be considered in most ESA status reviews. NMFS policy (NMFS 1993) stipulates that in determining whether a population is distinct for purposes of the ESA, attention should focus on natural fish (Waples 1991a). The decision to focus on natural fish is based entirely on ecosystem considerations; the question of the relative merits of hatchery versus natural fish is a separate issue. Fish are not excluded from ESA consideration simply because some of their direct ancestors may have spent time in a fish hatchery, nor does identifying a group of fish as natural as defined here automatically mean that they are part of a listed ESU. For a discussion of artificial propagation of Pacific salmon under the ESA, see Hard et al. (1992).

Transplants into Washington

It is commonly believed that even-year pink salmon historically either were absent from Washington or were at an abundance too low to sustain harvest (Rounsefell 1938, Atkinson 1956, Ellis and Noble 1959). Consequently, WDF made several attempts earlier in this century to establish even-year pink salmon runs in northwestern Washington (WDF 1916-1964, Neave 1965, Roppel 1982). These efforts are summarized in Table 4.

More than 82 million eyed pink salmon eggs were transported from Alaska to various locations in Washington in even-numbered years between 1910 and 1932. In addition, more than one million odd-year Alaskan eggs were brought into Washington from southeastern Alaska in 1929 (Table 5). An estimated 85 million juveniles resulting from these transplanted eggs (see explanation in Table 4) were released between 1911 and 1933; these releases produced no recorded returns of even-year adults to Washington rivers, including the Snohomish River (Ellis and Noble 1959, Neave 1965).

However, Neave (1965) stated that it appears that streams were not examined for actual escapements, and in 1924 the traps along the west coast of Vancouver Island, which had never caught pink salmon in the even-numbered, or off years for this variety, reported total catches of more than 20,000 small pinks, resembling the Alaska variety which had been transplanted (note that in 1923, over 14 million fry from Prince William Sound eggs were released into Washington waters, including nearly a million fry planted in the Skykomish River; Table 4).

Attempts to establish even-year pink salmon in the state were renewed between 1944 and 1956 with the transport of nearly 4 million eyed eggs from the Skeena River drainage in British Columbia (and possibly 200,000 eggs from Alaska in 1948; Table 4). Of the 1.3 million fry released, at least several hundred apparently survived to return as adults, but there is no evidence that returns were sustained beyond one or two generations (Ellis and Noble 1959, Neave 1965). The most substantial return appeared to result from a 1949 release of 299,000 fry (Lakelse River) into the Samish River, where an estimated 300-500 adults returned in 1950 (Neave 1965).

a - Neave (1965) reported 513,880 eggs taken to Green River Hatchery and 512,820 eggs taken to Puyallup Hatchery; Roppel (1982) reported 1,021,000 eggs taken to Auburn Hatchery.
b - Eyed eggs.
WDF = Washington Department of Fisheries.
NWIFC = Northwest Indian Fisheries Commission.
UW = University of Washington.
OSFC = Oregon State Fish Commission.
ODFW = Oregon Department of Fish and Wildlife.
OAF = Oregon Aqua Foods.
OSU = Oregon State University.
USBF = U.S. Bureau of Fisheries.

Artificial Propagation in Washington

A selected review of artificial propagation activity involving pink salmon in Washington is provided in Table 5. This review focuses heavily on historical stock transfers within the state. For about 25 years beginning in the 1950s, pink salmon were produced in Washington hatcheries around Puget Sound in relatively large numbers. Movements of fish among hatcheries and drainages in Puget Sound, Hood Canal, and the Dungeness River on the Olympic Peninsula were common during this period, but very few pink salmon were transplanted to areas outside Puget Sound. Three hatcheries have dominated pink salmon production in the state: Hood Canal Hatchery on Finch Creek in Hood Canal, Puyallup Hatchery on Voight Creek in southern Puget Sound, and Dungeness Hatchery on the Dungeness River on the Olympic Peninsula. In recent years, only Hood Canal Hatchery has maintained an active pink salmon production program. A population of odd-year pink salmon was established in 1953 at Hood Canal Hatchery from the gametes of adults returning to the upper Dungeness River (approximately 90%) and Dosewallips River (approximately 10%). Since then, production of odd-year fish has ranged from a low of less than 15,000 fry (in 1955) to a high of over 4 million fry (in 1988).

Summary

Although major efforts were made several decades ago to increase the abundance of even-year pink salmon in Washington, it is not clear that any of these attempts were successful. Even-year pink salmon are known in Washington only from the Snohomish River (WDF et al. 1993). The origin of this population is uncertain; these fish could be endemic or could have resulted from one or more transplants of even-year fish into the state. Regardless of its origin, however, this population appears to have been naturally self-sustaining for at least the last eight generations (its status prior to 1980 is unclear; WDF et al. 1993).

Most hatchery production of pink salmon in Washington is composed of odd-year fish released from Hood Canal Hatchery in southern Hood Canal. These fish are generally released into Finch Creek, the location of the hatchery, and the hatchery typically uses local broodstock (Table 5). As noted above, however, this broodstock was originally derived from adults returning to the Dungeness and Dosewallips Rivers in 1953. Hood Canal Hatchery production over the last decade has averaged about a million fry released locally every other year into Finch Creek (Table 5). Other recent releases, such as those into the Nooksack River, Voight Creek, Minter Creek, and Chambers Creek, have been relatively small and appear to have used local broodstock. Thus, although artificial propagation of pink salmon in the past--particularly stock transfers from Dungeness and Hood Canal Hatcheries around northwestern Washington-- may have affected the population structure of odd-year pink salmon in Puget Sound, recent hatchery production has probably had little effect on this structure.

Stock transfers of pink salmon in British Columbia are summarized elsewhere in Aro (1979) and NRC (1995).