Federal officials have confirmed the death of one of the wolves released in Colorado as part of the state’s voter-approved reintroduction efforts. 

“Initial evidence suggests that this wolf likely died of natural causes,” said Joe Szuszwalak, a spokesperson for the U.S. Fish and Wildlife Service.

The wolf carcass, found in Larimer County, was reported to the agency on April 18. The agency is conducting an autopsy to confirm the cause of death. The agency didn’t provide any additional details about the incident. 

Colorado Parks and Wildlife released 10 gray wolves on Colorado’s Western Slope in December and January as part of the state’s voter-approved reintroduction efforts.

Since their release, the wolves have spread out throughout the region. Using tracking collars, Colorado Parks and Wildlife has provided monthly maps showing the wolves’ general locations.

In recent weeks, wolves have killed several calves in the region. The depredation has heightened fears for ranchers, many of whom opposed the wolf reintroduction because of concerns it would continue to inflict economic hardships. 

Colorado Parks and Wildlife declined to comment on the wolf death, calling it an “active investigation.”