WCT Multi-state Assessment February 1 0, 2003 



Introduction 



Several status assessments have been conducted for westslope cutthroat trout (Oncorhynchus 

 clarki lewisi: WCT) over part or all of their historical range in recent years (Liknes 1984; Liknes 

 and Graham 1988; Rieman and Apperson 1989; Mclntyre and Rieman 1995; Duff 1996; Thurow 

 et al. 1997; Shepard et al. 1997; Lee et al. 1997); most of which were used by the U.S. Fish and 

 Wildlife Service (FWS) in their "Status Review for Westslope Cutthroat Trout in the United 

 States" (United States Fish and Wildlife Service 1999). Many of these previous assessments 

 were either conducted over only a portion of the historical range, involved only a few experts 

 knowledgeable about WCT, or suffered from a lack of consistency in the sources of information 

 used. This report updates the past assessments using a protocol that was consistently applied 

 throughout the historical range of WCT. We assessed the historically occupied range, current 

 distribution and genetic status, and distribution and risk for designated "conservation 

 populations" of WCT throughout their range. Fisheries professionals from throughout the 

 historical range of WCT in Montana. Idaho, Washington, Oregon, and Wyoming (state agencies. 

 Park Service. USFS. BLM. tribal, private, etc.) provided the information for this assessment 

 State fisheries staffs identified and designated "conserx'ation populations", but information from 

 many different sources was used to assess risks and threats to these populations. Although this 

 assessment provides consistent and current information on WCT that the FWS can use to make 

 their listing determination, the longer-tenn, and probably more significant use of this assessment, 

 is as an infonnation base that can be used by individual states and other agencies, working 

 collaboratively, to assess and prioritize their ongoing and future conservation efforts. 



The four states where WCT occur presently have the primary responsibility, under their 

 respective state laws, to manage and conserve WCT. Within specific portions of WCT range 

 Tribal governments and the National Park Service assume managerial authority for conservation 

 and management of WCT. The Forest Service, BLM and other federal land management 

 agencies are responsible for management of aquatic habitats on federal lands and for 

 coordination of land uses consistent with laws, rules, and regulations. The FWS is charged with 

 administration of the federal Endangered Species Act (ESA) and is currently re-evaluating a 

 recent finding (Federal Register 65: 20120) that WCT do not warrant listing as a threatened 

 species. It is mutually beneficial for the above parties to work together to: further the collective 

 knowledge, improve habitat conditions, and provide the best scientific information to the FWS 

 for making their listing determination. 



Analysis Area 



The analysis area included all of the known historical range of WCT within the United States. 

 We relied primarily on Behnke (1992) to delineate the likely historical range (Figure 1 ). This 

 area includes, from east to west, the upper portions of the Missouri, Saskatchewan, Columbia, 

 and Snake river basins in Montana, Idaho, and Washington; the John Day basin in Oregon; and 

 the Methow and Lake Chelan basins in Washington. This assessment does not include the 

 Canadian portion of the WCT range. 



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