The Importance of Roadless Areas for Native Trout
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Executive Summary
This report examines the distribution of healthy
populations of eight native trout species in the West (Maps: Bull Trout,Westslope Cutthroat,Greenback Cutthroat, Colorado River Cutthroat, Gila Trout). It is the most comprehensive and extensive analysis of its kind.

The report concludes that all eight species have experienced severe declines. Healthy populations remain in only in tiny portions of their former ranges - averaging less than 5%. Three of the eight species are strong in less than 1% of their historic range. The remaining strong populations of all eight species were associated with roadless areas. For five of the eight, the majority of their strongholds were in roadless areas.

The analysis clearly indicates that western native trout species are highly imperiled, and complete protection of roadless areas is essential to their persistence .

The decline of native trout is caused primarily by habitat damage (much of it associated with roads), and the effects of introduced, non-native, fish. Two native trout species are already extinct. About half of the remainder are listed under the Endangered Species Act. There is a very high risk of continuing loss of strong populations due to their precarious population status, widespread habitat degradation, and continuing intrusion into roadless areas.

Like native trout, the extent of roadless areas on public lands has radically declined since the 1950s. The Bureau of Land Management (BLM) and Forest Service (USFS) have not protected roadless areas: more than 2.8 million acres of inventoried roadless areas have been lost over the last two decades on USFS lands alone. Millions more acres have been lost on BLM lands.. Most remaining roadless areas - many of which house or nurture strong trout populations -- are not protected from roads, from oil and gas exploration, and other associated degradation.

The report's results corroborate previous assessments and scientific literature, which have consistently concluded that roadless areas and other high quality habitats are essential components of native trout conservation. Similarly, scientific literature has consistently shown that roads and associated activities are one of the most severe and persistent sources of trout habitat damage. This report summarizes this information.

The report is based on computerized Geographic Information Systems (GIS) analysis of trout distributions and roadless areas using data from government and academic sources. The eight native trout species that were analyzed have distributions that cover much of the West. Therefore the results provide a geographically robust indication of the importance of roadless areas for native trout.

The loss of roadless areas is irreversible. Our report provides the public with information on the intrinsic tradeoffs of failing to protect roadless areas on lands managed for the American people by the United States Forest Service, Bureau of Land Management, and National Park Service.

In sum, our analysis, the scientific literature, and pertinent government assessments indicates that in the face of the severe declines of these native trout, and their dependence on high quality habitat frequently associated with roadless areas, the full protection of all roadless public land, including uninventoried areas greater than 1000 acres, is essential to the restoration and protection of native trout in the West.