Zion National Park’s Bighorn Population Explodes, Officials Eye Transplant

Daniel Xu | February 25, 2014


Zion National Park may be shipping out some of its bighorn sheep to help restore populations elsewhere.

Utah’s Zion National Park is experiencing a sheep boom, and experts say some of the animals may have to be transported outside the park to keep the herd healthy. According to park officials, a recent survey counted more than 500 desert bighorn sheep living within and outside the boundaries of the park. Since such a dense gathering of sheep can promote disease in both the bighorn and nearby domestic goats and sheep, the Utah Division of Wildlife Resources (UDWR) is working with the park to determine management actions. How much is too much of a good thing? Biologist Cassie Waters told The Salt Lake Tribune the park can hold about 800 bighorn sheep, but such a high density of animals could lead to fatal diseases such as pneumonia. Respiratory diseases are especially dangerous to bighorn sheep and are commonly contracted from domestic sheep since they are behaviorally attracted to each other. Outbreaks of pneumonia can devastate entire herds, and according to the UDWR, 88 percent of pneumonia die-offs occur within three years of peak population estimates. However, Zion’s bighorn population is still healthy. Although cases of sore mouth disease were reported last year, park officials agreed they see no signs of die-offs. Biologists are hoping to keep it this way by trapping and transferring a number of sheep to boost restoration efforts in other areas. Continue Reading→