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3. Present Distribution - Probably extinct. Not collected since 1891. Because of the above description and a re- ported small-spotted cutthroat trout in the Eagle River (Colorado River drainage), reminant populations may still be found in isolated headwater streams. 4. Existing Management Plans - A transplant from Twin Lakes was attempted into Island Lake on Grand Mesa in the early 1900's, probably unsuccessfully. The State DOW no longer recognizes the subspecies. 5. BLM Interest - Minimal. Some priority given to Eagle River inventory. E. In addition to these four subspecies of S. clarki, there are several other subspecies of cutthroat trout on state threat- ened and endangered lists in western drainages. Two other species of Salmo from the Colorado River drainage are on the federal Endangered Fauna (1974) list: Salmo ilae known now only from the upper Gila drainage, New Mexico, and Salmo a ache, under fairly intensive management in Arizona, originally from high tributaries of the Salt and Little Colorado rivers, Arizona. It is anticipated that all of the cutthroat trout subspecies native to Colorado presently exist somewhere on NRL. Rare fish are constantly being rediscovered by biologists who earlier listed them as extirpated from the drainage. Small headwater streams in the Southwest are especially ef- fective in acting as refugia for fish species retreating from human disturbance and exotic species competition (Minckley and Deacon, 1968). Fish inventories are difficult and time consuming in these small streams, but are necessary in order to identify these last strongholds of native fish species. II. Minnows and Suckers In Colorado, all the warm water threatened and endangered fish species on the federal lists are relatively large fish from the Colorado River and its major tributaries. One other species, Gila ele ans, is sympatric, faces the same problems, and is iden- tified on the state list. These species evolved in the turbulent, silt laden Colorado River and its tributaries, relatively isolated from other fish species not adapted to survive in such a harsh environment. The unusual shape of all four species, small heads and eyes, wedge shaped anteriors, thin caudal peduncles, large pelvic and caudal fins, are all adaptations to help keep the fish on or near bottom in turbulent currents without constant energy 11