ANTELOPE ISLAND — The Utah Division of Wildlife Resources released 25 Rocky Mountain bighorn sheep on Antelope Island Wednesday afternoon, hoping to establish a new herd.

The sheep were transplanted from Rocky Boy’s Reservation in Montana, according to Jace Taylor, bighorn sheep biologist with DWR.

Though bighorn exist elsewhere in Utah, DWR brought them from Montana because the Montana sheep were the desired species and met strict health criteria. The transplanted sheep also need to provide genetic diversity, since the new herd on Antelope Island will function as a nursery herd, used to populate other herds around the state, Taylor said.

While cowboys have long been a symbol of the rugged American West, they were preceded long before by bighorn, which survive in some of the most challenging terrain.

“They’re majestic animals. They’re emblems really of Western, rugged wilderness,” Taylor said. “They live in some of the most rugged areas, at some of the highest peaks in Utah in extreme conditions. ... Today, in January, we have bighorns living at 13,000 feet.”

Bighorn are diverse, fearless and have a strong will to survive, he said.

The strong will to survive highlights how heavy a blow it was to state park and DWR staff when the previous herd of 150 bighorn sheep on the island was decimated by respiratory disease in late 2018. The thriving herd had also been functioning as a nursery herd, Taylor said.

The respiratory disease, similar to pneumonia, was caused by bacteria, Taylor said. While treatment for the disease exists, it’s time and cost intensive, requiring treatments multiple times a day and months-long, stressful confinement for infected animals, which is not realistic to administer to an entire herd, Taylor said. There would also be no guarantee the animals would survive, he said.

Because the remaining sheep were a risk to any sheep added to the island, they were euthanized starting in January 2019, Taylor said.

The situation was perplexing, given that bighorn are relatively protected and isolated on Antelope Island — and Taylor says no definitive explanation for the spread of the disease has been determined.

However, in preparation for the new herd, a wildlife fence has been placed around the southern part of the island to prevent bighorn from leaving the island during low water years — and to prevent other animals from entering, Taylor said.

In addition to raising bighorn sheep for other parts of the state, the herd on Antelope Island will again fill the species’ long-held role in the ecosystem of the island.

“They have an important niche — to the predators ... to the habitat, too,” Taylor said. “There’s probably aspects of the vegetation, of the habitat that we don’t completely understand, but we know that it evolved with bighorn sheep. It’s important to have bighorns in Utah again. We probably will never reach the levels we were at presettlement, but we’re going to do our best to have healthy bighorns in Utah.”

With that growing population comes more opportunity for Utahns to see the animals.

Jeremy Shaw, manager of Antelope Island State Park, says the two best places to spot them on the island are Frary Peak Trail and the West Side Trail. True to bighorn territory, both hikes are pretty intensive, so prospective hikers need to be dedicated, he said.

“Anybody who gets the chance to ... see bighorns either on Antelope Island or any other place that’s been able to restore them, I think it’s a great privilege,” Taylor said. “They’re such cool animals to watch — navigating their landscape, watching them interact — they’re very social. They’re incredible.”

Contact reporter Megan Olsen at molsen@standard.net or 801-625-4227. Follow her on Twitter at @MeganAOlsen.

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