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Oreaon Information on westslope cutthroat trout in Oregon was obtained through surveys completed by Errol Claire, Oregon Department of Fish and Wildlife. Westslope cutthroat trout occur in small disjunct populations in the John Day River Basin. There are 23 populations confined to the headwaters in the upper John Day River consisting of about 20 tributaries in the upper mainstem and several tributaries in the North Fork John Day River. Dr. Robert Behnke, Colorado State University, has meristically determined the upper mainstem population to be westslope cutthroat trout in 1980 based upon 24 fish from 8 streams (Errol Claire, Oregon Department of Fish and Wildlife, personal communication). Historically, westslope cutthroat trout occupied about 10% (currently 1 %) of North Fork John Day River drainage and are now considered at risk and declining due to the vulnerability of its shrinking habitat and critical habitat requirements. The upper mainstem population is also considered at risk for similar reasons but is more common, historically occupying 25% (currently 5%) of the drainage (Errol Claire, Oregon Department of Fish and Wildlife, personal communication). Westslope cutthroat trout are believed to have occupied 179 miles in the two drainages and currently occupy 73 miles or 41% of their historic habitat (Kostowet a!. 1994). Grazing, timber harvest, and irrigation diversions have degraded habitat and restricted these popula- tions into small headwaters. Most populations are on private land. The trend in abundance and distribution could stabilize given new forest management, habitat restoration efforts and ecosystem restoration (Errol Claire, Oregon Department of Fish and Wildlife, personal communication). Washinaton Washington has several disjunct populations of westslope cutthroat trout in the Yakima, Methow, Lake Chelan, Entiat, and Wenatchee rivers (Behnke 1992). Endemic cutthroat trout are considered to be glacial relics from the early Pleistocene when post-glacial flooding established populations above barrier falls which excluded competing species such as rainbow trout and steelhead (Mullan et aI. 1992). Cold water temperatures below hanging valleys, for example in the West Fork Methow River, are thought to favor cutthroat trout and exclude competing species that are capable of displacing cutthroat trout (Ken Williams, Washington Department of Wildlife, personal communica- tion). The Washington River Information System currently lists 1,557 stream miles occupied by westslope cutthroat trout. The upper Yakima, Wenatchee, Methow, Lake Chelan, and Pend Oreille drainages, respectively, have the highest occupancy. But a high percentage are probably the result of introduc- tions (Ken Williams, Washington Department of Wildlife, personal communication). Stocking pro- grams for westslope cutthroat trout in Washington date back to 1903; the brood sources probably came from Lake Chelan or the Wenatchee River drainage (Ken Williams, Washington Department of Wildlife, personal communication). Declines in Lake Chelan adfluvial cutthroat trout populations were noted as early as the 1920's as anglers could catch "native cutthroat" with regularity only in headwater streams of the Stehekin River. A 10 fish sample from such a stream, Flat Creek, in 1982 was confirmed as pure westslope cutthroat by Dr. Behnke. However, much of the historic distribution of endemic westslope cutthroat trout in Washington is clouded because of extensive stocking of alpine lakes and the subsequent colonization of tributary streams. In 1992 and 1993, samples of trout were taken from the Methow, Wenatchee, and Entiat river watersheds to determine the distribution of pure and hybrid trout populations in the mid-Columbia River area (Proebstel et a!. 1995). In the Methow watershed, a total of 84 sites were sampled within the 32 different tributaries and 4 lakes visited. In the Wenatchee watershed, 41 sites were sampled 5