A moose in Montana has tested positive for chronic wasting disease (CWD) for the first time. The finding expands the area wildlife managers believed the disease to exist.

The moose was killed north of Troy, just a half of a mile outside of the Libby CWD management zone, which spans a 10-mile radius around Libby. Thirty white-tailed deer have tested positive for CWD within the management zone since the disease was discovered this spring.

CWD can infect, deer, elk and moose. White-tails are easily impacted because they’re social animals. CWD can quickly spread through herds via contact, feces and urine, but moose are relatively solitary animals.

“It is surprising. It’s unfortunate news, but the silver lining is that moose are solitary animals. They don’t socialize with deer and elk. They even don’t socialize amongst themselves very often,” says Montana Fish, Wildlife and Parks (FWP) spokesperson Dillon Tabish.

Tabish says that means the animal was less likely to have spread the prions, or misfolded proteins, that cause the fatal disease directly to other cervids.

He says it’s hard to say how this moose contracted the disease.

“But it could have occurred from sticking its nose in a deer carcass that was infected. It could have stuck its nose or shared a water source where there was a dead carcass in the water source and that was carrying prions that have CWD.”

FWP hopes to collect samples from 400 hunter-harvested and trapped white-tailed deer inside of the Libby management zone in order to understand prevalence. FWP expects to have the full results early next year, which will guide future management actions. The agency is also sampling mule deer, elk and moose taken in the management zone and is encouraging hunters harvesting animals nearby to voluntarily submit samples.