Our major accomplishment of the past year has been retirement of two domestic sheep grazing allotments on the Beaverhead-Deerlodge National Forest in southwestern Montana. These bands of domestic sheep have been causing serious disease problems for two separate bighorn sheep herds – resulting in upwards of 75% mortality – for more than three decades.
Bear Canyon (4,586 acres) and Indian Creek (7,483 acres) lie in the headwaters of the Beaverhead River, southwest of Dillon, Montana. Bear Canyon lies on the west face of the Tendoy Mountains, while Indian Creek stretches across the Continental Divide on the Idaho/Montana. This area is a key corridor that connects the Greater Yellowstone Ecosystem with the Salmon-Selway Ecosystem to the north in Idaho.
For the last several decades, the Forest Service has permitted domestic sheep (1,200 ewes and lambs) to use these areas in the summer. Much of this area is dry, high-elevation grassland with aspen groves and conifer stands. The conflict arises because domestic sheep are known to transmit diseases to bighorn sheep that can result in dramatic die-offs of the wild sheep.
These two allotments have precisely that history. Bighorn sheep were introduced to the Tendoys in 1984; the herd thrived for its first decade, but then experienced a die-off in 1993 that killed 75% of the herd (which then numbered close to 100). The herd began to build back up again, only to experience another devastating reduction in 1999, when 75% of the herd was again lost to disease. The bighorn sheep herd adjacent to Indian Creek, which lives part of the year in Idaho, has also experienced die-offs, though not as severe as Bear Canyon.
It cost NWF $50,000 to retire these two allotments from domestic sheep grazing. Our agreement with the rancher allows him to graze a small number of cattle for a short period of time on one of the allotments. There’s no conflict between the small number of cattle and the bighorn sheep herds. It’s a solution that worked not only for the bighorns, but for the rancher, as well.