FWP killing more bighorn sheep at Bonner
FWP
Montana Fish, Wildlife & Parks (FWP) has accelerated the lethal removal of bighorn sheep from the Bonner herd just east of Missoula since a pneumonia outbreak was first detected in two bighorn on January 12th.
Originally wildlife officials hoped that the nearly always-fatal respiratory disease was limited to approximately 65 sheep that were spotted in the West Riverside and Bonner communities and nearby lands. Now officials have documented the presence of the disease to the east of this zone and estimate that the impact of the outbreak is larger than originally estimated. Approximately 95 of the estimated 160-180 sheep in the Bonner herd may be infected or exposed.
In all, wildlife officials had lethally removed sixty sheep by Wednesday afternoon, with plans to continue daily operations to remove sheep in what is being called the disease containment zone, an area that includes the West Riverside and Bonner communities and land lying between Marshall Canyon and about two miles east of Johnson Gulch. The sheep removed through Wednesday included 41 ewes, 12 lambs and seven rams.
“If we’re lucky, the sacrifice of sheep carrying pneumonia in West Riverside and nearby areas will prevent the catastrophic loss of the whole Bonner herd,” said Vickie Edwards, FWP wildlife biologist in Missoula.
The strategy is to eliminate the possibility of infected sheep moving out of the containment zone to mix with healthy sheep elsewhere. Wildlife officials estimate that this might translate into the removal of approximately 90 total sheep from the Bonner herd.
In extreme cases, pneumonia-related outbreaks among bighorn sheep can result in herd "die-offs” where 80 to 90 percent of the herd is lost. There are no known vaccines to prevent pneumonia in wild sheep, or medications that can be practically applied to prevent the death of sick individuals.
The pockets of the Bonner herd that biologists hope to spare from the disease are those living in the Rattlesnake Wilderness and those found southeast of Bonner, often spotted south of Highway 200.
“Unfortunately the number of sheep that we’re looking at removing is higher than we originally thought,” Edwards said. “But as we continue our removal and monitoring efforts we are finding more and more sheep that are exhibiting symptoms or have been exposed to the disease.”
In addition to preventing the likelihood of loss of the entire Bonner herd, lethal removal of the sick sheep will decrease opportunities for infected sheep to come in contact with sheep from other nearby herds, including those in the Rock Creek, Evaro and Bearmouth areas.
Aside from daily or weekly movements between habitats, bighorns sometimes disperse long distances. In early December, FWP biologist Jay Kolbe observed “a decent ram” just north of Seeley Lake, where no one could remember seeing one in a long time, according to Kolbe. He has been working along with several other FWP biologists and wardens on the West Riverside containment.
“We really hope to keep this thing localized to protect our other herds,” Kolbe cautioned. “Once infected, bighorns become their own worst enemies if one decides to go on a walkabout.”
Sheep collected in the effort are tested for confirmation of pneumonia, and the horns and heads will be preserved for educational purposes in schools and conservation organizations.
Because the sheep have compromised immune systems and may also be carrying secondary infections, biologists are using extra caution and are not able to donate the meat to local food banks. There have been no known cases of humans or pets contracting pneumonia from wild sheep, but FWP cautions anyone who finds dead or sick bighorn sheep to leave the animal alone and call FWP in Missoula at 406-542-5500.
Edwards is quick to acknowledge the help and support of West Riverside residents, including those that first reported sheep exhibiting symptoms of the disease.
“We couldn’t be doing this without the cooperation of this community. No one likes what’s happening here. But, most see the greater good,” Edwards said.
|
Follow us
on Facebook
Contact us
Copyright, 2009,
Montana Outdoor Radio Show
Web work by BigSkyOutdoors.Net
|
|
|
