The Upper Big Hole Valley

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The Upper Big Hole is the widest mountain valley in southwestern Montana, with much of the valley floor above 6,000 feet in elevation. The Big Hole River begins in the Beaverhead Mountains and winds for about 150 miles through the valley. It’s a world-renowned native trout fishery and the only river in the lower 48 states that still supports river-dwelling Arctic grayling, a fish that has been nominated for "endangered" status.

The surrounding mountains sustain a wealth of wildlife, from the rare wolverine, to moose, elk and deer. Abundant wetlands harbor beaver, muskrat and more than 40 species of birds and waterfowl.


The valley is sparsely populated, with about 900 residents, and an economy based mainly on ranching. But, as in most of Montana’s scenic valleys, development pressures are increasing

Over the years, irrigation systems have reduced summer river flows, which can be harmful to the grayling.

Goals & Strategy

The Conservancy has joined with public agencies, conservation groups and the local ranching community to place conservation easements on more than 40,000 acres in the valley, and our goal is to continue advancing conservation in this beautiful place.

Perhaps as important as the land protection efforts are the cooperative conservation agreements aimed at protecting grayling habitat. These agreements focus on restoring riparian areas, maximizing water flows and making irrigation systems more fish-friendly.