HURRICANE – Three desert bighorn sheep were euthanized Feb. 27 near Hurricane, in a move wildlife managers say was necessary to protect the region’s thriving bighorn population from a devastating disease.
The three bighorn sheep were reported by a resident and were located in the Hurricane Cliffs east of Hurricane in the area of Highway 59, Utah Division of Wildlife Resources Conservation Outreach Manager Lynn Chamberlain said.
It is not known where the sheep came from, but they had wandered into a buffer zone that wildlife managers maintain around a healthy and thriving bighorn herd centered in and around Zion National Park.
The Zion herd is the largest bighorn sheep herd in Utah. The herd has been tested four years in a row and found to be disease-free, Chamberlain said.
“Which is excellent, there are other sheep units that can’t say that.”
Wildlife managers are very protective of the Zion herd because they are disease-free and can be transplanted to other areas as needed.
“Nobody wants to euthanize sheep, that’s not what we do and that’s really not what we’re excited about. But in order to protect that herd and those 800 sheep and the disease-free certification that they have, we had really no choice but to euthanize those three sheep that came into Hurricane. And that’s the bottom line.”
In particular, wildlife managers are trying to avoid infection of the Zion herd with a pneumonia-type virus that is 80 to 90 percent fatal, Chamberlain said. Even the sheep that do survive are not healthy and cannot rebuild the herd because the disease is transmitted from ewes to lambs and then the lambs die.
“So you end up with a herd that’s decimated down to 10 or 20 percent of what it should be, and it cannot grow because reproduction can’t happen,” he said. Managers can’t rebuild the herd by transferring more sheep in, because they will catch the disease and die.
“It’s a difficult management issue for us.”
Testing the animals for disease rather than euthanizing them is not an option because test results take weeks and bighorn sheep cannot be held in captivity because they become too stressed.
“It would be ideal if we could just capture them and take their blood and test them on the spot to see if they have it, but unfortunately that test takes a minimum of about two weeks,” he said.
Fortunately, the desert bighorn sheep don’t move around much. It is only the first or second time wildlife managers in Southern Utah have had to euthanize sheep for crossing into the buffer zone.
The closest and most likely source of the three wandering desert bighorn is a herd in Arizona, which is not certified as disease-free.
“This (Zion herd) is a precious commodity to us. Not from a monetary standpoint, but from a standpoint of having a sheep herd we can actually transplant sheep from if we need to.”
The Zion herd has made a comeback in recent years. After 30-40 animals were transplanted from Nevada in the 1970s, they disappeared and were presumed to have been killed by mountain lions.
Then in the 1990s, park visitors began reporting an occasional sighting. More and more were seen until four or five years ago a helicopter survey was done, Chamberlain said. Biologists were surprised to find hundreds of healthy bighorns in Zion National Park and in the red rock areas surrounding the park.
The Zion herd is thriving and healthy and its numbers are growing, Chamberlain said, enough so that sheep need to be transplanted out to control the population. Wildlife managers in several states have a cooperative agreement to trade healthy animals; trading keeps costs down.
“We’ve actually moved elk to Kansas, in exchange for wild turkeys and for other things we might want to bring back here.”
The Zion herd is also hunted for trophy-class animals on a very limited basis, and hunters draw for a once-in-a-lifetime opportunity, Chamberlain said. Keeping the herd thinned and spread out through both hunting and transplantation reduces the risk of disease transmission.
The euthanization of three sheep in Hurricane was approved by the director of the Utah Division of Wildlife Resources in Salt Lake City, Chamberlain said.
Wildlife officials drew blood and tissue samples from the three sheep, however the results won’t be back for weeks. Officials are reasonably positive the animals are not disease-free.
“We’re in the business of building healthy herds and flocks,” Chamberlain said. “And the last thing we want to do is to have to go in and get rid of some of those animals, but in the case of the sheep in Hurricane, it was three animals here or 800 animals there. We had to decide which one was going to go, and obviously it was the three animals that had to be taken out.”
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