HAMILTON – For the second time in six years, the bighorn sheep herd in the East Fork of the Bitterroot appears to be suffering a die-off from an outbreak of pneumonia.
Montana Fish, Wildlife and Parks' Bitterroot-based biologist Rebecca Mowry is asking for people’s help in keeping tabs on the herd in an effort to keep the illness from spreading.
The bacteria-caused pneumonia was verified Saturday.
“Someone called about a sick ram that was right next to the road,” Mowry said. “A warden put it down. Its lungs were full of fluid.”
In an aerial survey Monday, Mowry found numerous other animals that were showing signs of pneumonia.
“I surveyed the herd from a helicopter,” she said. “We would push them a little to see if any would start coughing. Somewhere between a fourth and a third of them that we saw started coughing.”
Mowry hopes to keep the illness from spreading to the Painted Rocks bighorn sheep herd in the West Fork of the Bitterroot, which has been one of just a few in the state that’s managed to escape a die-off from pneumonia.
During this spring’s elk survey, Mowry spotted some bighorn sheep occupying lands in between the east and west fork herds.
“There is a possibility of some connectivity between the two herds,” she said.
Local residents can help by reporting any sick or newly dead sheep they encounter.
“If they see sick sheep, they should let us know immediately,” Mowry said. “The sick ones cough a lot, especially if pushed. They sound awful. They might be skinny, too.”
At this point, she plans to keep a close eye on the population in the East Fork to see how the illness manifests itself, especially survival of lambs. Sometimes the adult sheep can survive a bout of pneumonia, but they lose their lambs.
“I will be paying special attention the lamb recruitment this year,” she said.
The department will also consider making adjustments to this year’s quota for the hunting season. Presently, the quota is set at three rams. Mowry said that number may be dropped back to one.
“We’re not entirely sure how that will go over at this point,” she said. “What we do tend to see is that herds that go through die-offs seem to recover. Hopefully, this herd will bounce back in a few years, but that’s something we will have to wait and see.”
The last die-off for the East Fork herd occurred in 2009.
During the event, biologists attempted to cull out as many of the sick animals as possible to keep the illness from spreading. While initially it appeared to be a success, the disease started popping up in surrounding herds shortly thereafter.
The Painted Rocks herd hasn’t been hit with the disease.
“My biggest priority is going to be to keep it out of the West Fork,” she said. “We’ll do whatever we can to keep it out of there.”