The herd of bighorn sheep near Thompson Falls continues to decline at alarming rates, according to recent surveys by Montana Fish, Wildlife and Parks.
FWP Biologist Bruce Sterling counted only 52 sheep on his annual flight this spring, compared to 270 counted in 2008, according to a news release sent out Tuesday. The surveys reflect the number of sheep observed, not the total number of sheep in the population.
The trend is alarming, Sterling said. He attributes most of the decline to highway mortality. Between 2008-12, a total of 110 sheep (50 ewes, 60 rams) were killed by collisions. A total of 107 sheep were killed on Montana Highway 200 and three were killed by trains. Since 1985, 403 sheep have been killed on the highway and 58 sheep were killed by trains, according to FWP.
“We have lost 50 breeding or potentially breeding females during this time frame when hunters have taken only five ewes on permits,” Sterling said in a statement.
Sterling said the highway mortality problem has been ongoing for decades but seems to be more serious in recent years, noting that five sheep were taken out in one collision recently.
“Now that we are at a low population level for sheep, each mortality is more critical,” Sterling said.
A number of steps have been taken to reduce highway mortalities of sheep but have proven ineffective, Sterling said. FWP has installed yellow flashing caution signs and reader boards, but they have not been successful in convincing drivers to slow down and avoid collisions with sheep, he said.
The problem will be discussed at an upcoming meeting with Montana Department of Transportation officials on May 10.
Bighorn sheep were native to the Thompson Falls area but populations were hurt by overhunting and disease passed by domestic sheep. Bighorns were re-introduced in the mid 1950s.