By PERRY BACKUS of the Ravalli Republic | Posted: Wednesday, January 20, 2010 6:45 am | No Comments Posted
Font Size: Default font size Larger font size HAMILTON – Montana Fish, Wildlife and Parks biologists are taking the lessons learned in the Bitterroot late last year to try to slow the spread of a disease killing bighorn sheep in the Bonner area.
Biologists have culled nearly 40 bighorns from the West Riverside community east of Missoula in an effort to interrupt the spread of highly infectious pneumonia.
Last November, state biologists shot more bighorns infected with pneumonia in the East Fork of the Bitterroot in an unprecedented attempt to preserve that herd.
Bighorn sheep herds around the West periodically experience disease outbreaks that often wipe out as much as 80 percent of the population. Until now, the official response has been to let the disease run its course.
“The jury is still out on whether we’ll succeed or not,” said FWP Wildlife Manager Mike Thompson. “If we hadn’t had the experience that we had in the East Fork, I’m not sure that we would have tried this.”
The situations are a bit different.
In the East Fork, biologists were able to spot ailing sheep and dispatch them. At times, the sick sheep were commingling with other healthy bighorns.
At West Riverside, the outbreak was caught in an earlier stage, but apparently the disease spread more quickly. That herd is confined to a much a smaller area.
Only a fraction of the 38 bighorns culled from the herd by Monday were seen coughing or exhibiting other symptoms. All of the sheep were infected.
“Every single one of them has been sick, even though they’re not all outwardly displaying symptoms,” Thompson said.
FWP will probably cull the entire West Riverside herd of about 65 animals, he said.
The West Riverside herd is one of four herds that use the Bonner area. The other three herds haven’t shown any symptoms up to this point.
“We’re looking for the nearest healthy sheep,” he said. “We’ll test them to see if they are in fact healthy. And then we’ll make a determination if our line of containment is sufficient.”
Thompson said there likely is movement between the herds, especially in the spring when young rams begin to disperse.
There is no way of knowing for sure if this strategy is going to work, but biologists are hopeful.
“We’ve seen evidence of success in the East Fork, but it’s going to take some time for us to know for sure,” he said. “We have been encouraged that we’re doing something useful to save healthy bighorns. We’re encouraged enough to keep moving forward with this strategy.”
Font Size: Default font size Larger font size HAMILTON – Montana Fish, Wildlife and Parks biologists are taking the lessons learned in the Bitterroot late last year to try to slow the spread of a disease killing bighorn sheep in the Bonner area.
Biologists have culled nearly 40 bighorns from the West Riverside community east of Missoula in an effort to interrupt the spread of highly infectious pneumonia.
Last November, state biologists shot more bighorns infected with pneumonia in the East Fork of the Bitterroot in an unprecedented attempt to preserve that herd.
Bighorn sheep herds around the West periodically experience disease outbreaks that often wipe out as much as 80 percent of the population. Until now, the official response has been to let the disease run its course.
“The jury is still out on whether we’ll succeed or not,” said FWP Wildlife Manager Mike Thompson. “If we hadn’t had the experience that we had in the East Fork, I’m not sure that we would have tried this.”
The situations are a bit different.
In the East Fork, biologists were able to spot ailing sheep and dispatch them. At times, the sick sheep were commingling with other healthy bighorns.
At West Riverside, the outbreak was caught in an earlier stage, but apparently the disease spread more quickly. That herd is confined to a much a smaller area.
Only a fraction of the 38 bighorns culled from the herd by Monday were seen coughing or exhibiting other symptoms. All of the sheep were infected.
“Every single one of them has been sick, even though they’re not all outwardly displaying symptoms,” Thompson said.
FWP will probably cull the entire West Riverside herd of about 65 animals, he said.
The West Riverside herd is one of four herds that use the Bonner area. The other three herds haven’t shown any symptoms up to this point.
“We’re looking for the nearest healthy sheep,” he said. “We’ll test them to see if they are in fact healthy. And then we’ll make a determination if our line of containment is sufficient.”
Thompson said there likely is movement between the herds, especially in the spring when young rams begin to disperse.
There is no way of knowing for sure if this strategy is going to work, but biologists are hopeful.
“We’ve seen evidence of success in the East Fork, but it’s going to take some time for us to know for sure,” he said. “We have been encouraged that we’re doing something useful to save healthy bighorns. We’re encouraged enough to keep moving forward with this strategy.”
