(KUTV) -- Big Horn Sheep on Antelope Island are dying from a rare respiratory disease.
Biologists with the Utah Division of Wildlife Resources tested tissue samples from the animals last month and found the sickness.
In November 2018, there were 150 Big Horn Sheep on the island. DWR recently surveyed the island and found 26 still living.
“It’s really hard to see something like this happen,” Mark Hadley, DWR spokesperson, said.
Big Horn Sheep are native to Antelope Island. Hadley said historical records show sheep on the island as far back at 1847. But, the species eventually disappeared from the island. DWR began reintroducing the sheep in 1997.
“Up until last fall, the herd has done really, really well on the island,” Hadley said.
Wild sheep typically get the illness from domestic sheep.
“It’s a little bit of a mystery, though, how the sheep out here on Antelope Island got the disease, because we’re not aware of any domestic sheep being out here or goats on the island,” Hadley said.
DWR is trying to determine how the sheep got sick to prevent it from happening again. The surviving sheep will be euthanized by the end of January.
“This disease is confined to the Big Horn Sheep on the island. It’s not a disease that can be passed on to the other wildlife on the island,” Hadley said. “I guess if there’s any good news in this, it’s that.”