BILLINGS — Conservationists have filed notice they’ll sue federal wildlife managers over a decision not to protect a unique population of fish in Montana.
The U.S. Fish and Wildlife Service in August said Arctic grayling don’t need special protections due to efforts by landowners and government agencies to preserve the fish.
But conservationists say that’s not been enough to reverse the fish’s decline. They say drawing irrigation water from the Big Hole River south of Butte continues to threaten one of the grayling’s last remaining refuges in Montana.
Thursday’s notice was filed by Center for Biological Diversity, Western Watersheds Project and two individuals.
The Missouri River system upstream of Great Falls holds the only Arctic grayling population in North America outside Canada and Alaska. The fish are related to trout and known for a sail-like dorsal fin.