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River) and those in Yellowstone Lake but does not raise the possibility of these fish being different species. While Behnke (1992) continues to believe thatthe evolutionary and ecological reality of the existence of the finespotted cutthroat warrants subspecies status, he also acknowledges that the difference in spotting pattern might be the result of two alleles occurring at one gene locus as shown for brown trout (Skaala and Jorstad 1988). It is anticipated that continued research into the genetic and taxonomic status of both the finespotted and largespotted forms will continue and there is the possibility that more definitive information will bring the discussion to a close, one way or the other. For the purposes of this assessment, both the large and finespotted forms will be treated as Yellowstone cutthroat trout with the information on the two cutthroat forms being presented both in combination and separately depending upon the type of information reported. Within the Yellowstone River drainage, cutthroat trout occupied a substantial number of headwater streams as indicated in both Jordan's (1891) and Evermann's (1891) reports which provide informa- tion from areas in and adjacent to Yellowstone National Park. Jordan paid particular attention to the many falls within the Park which had served as barriers to fish movement and projected that the area above the falls, in aggregate, would equal 1,500 square miles. Actual extent of cutthroat distribution within the lower portions of the Yellowstone River drainage was not well documented. The fact that cutthroat trout were documented in the upper reaches of the Tongue River drainage (Evermann and Cox 1894 and Willert 1986) and not in the lower portions of the Tongue and other tributaries or even the lower Mainstem Yellowstone (Coues 1893 as noted in Evermann and Cox 1894) leads one to ponder on just how much of the lower Yellowstone River drainage was actually occupied at the time of early exploration and settlement. From a prehistoric perspective, it is very possible that there were periods of time when climatic conditions (e.g. cooler and wetter periods) would have allowed for population expansion down to and including the Tongue River. During such conditions it would be expected that the entire Bighorn River drainage, Yellowstone River, and Tongue River could have been suitable for cutthroat trout. It is also possible that cutthroat located in the upper Tongue River were a result from a basin transfer from the Little Bighorn River basin. Both options are feasible given climatic variability and topographic characteristics. From a historical perspective and for the purpos- es of this assessment, Yellowstone cutthroat trout distributional range will not include the lower portion of the Tongue and mainstem Bighorn River drainages. In addition, the historical range will not include that portion of the mainstem Yellowstone River from just above the confluence of the Bighorn River downstream, including all tributary streams. ASSESSMENT METHODS The basic intent of this assessment effort was to provide a more definitive appraisal of current distribution, condition and abundance of Yellowstone cutthroat trout within their historic range with specific attention focused on State and Forest Service administrative jurisdictions. To accomplish this, information associated with historic and current distribution and condition characteristics was obtained from biologists from State Wildlife Agencies and various National Forests. For the area within each State, these knowledgeable individuals completed localized assessment questionnaires. In addition to information associated with distribution, the questionnaires also addressed factors related to population well-being and habitat condition. The information was collected on a sub-basin basis with the assessment boundaries being determined by the local biologists. Each sub-basin contained one or more drainages or sections of drainages. For each of these assessment areas, a standard set of questions was addressed and the most pertinent responses were recorded. It should be noted that quality and precision of the information collected represent, to a large degree, best professional knowledge of the biologists based upon specific experience and knowledge of individual streams and populations. In some instances, data bases were used to provide the needed information. 14