DENVER (KDVR) — Bird flu has been linked to three mammalian deaths in Colorado, including a black bear, a skunk and a mountain lion, according to state wildlife officials.

Colorado Parks and Wildlife said the animals tested positive for the highly pathogenic avian flu after wildlife officers found symptoms either before or after their deaths. Cases among other mammals in the state are suspected.

CPW said the animals likely contracted the virus from eating birds.

“It’s not completely surprising, because this does happen with avian influenza,” CPW spokesman Travis Duncan told FOX31’s Ashley Michels. 

Bird flu linked to 3 mammalian deaths in Colorado

In January, a dead mountain lion discovered just outside the Gunnison city limits was found to have symptoms of the bird flu, like necrosis of the liver and pneumonia. A skunk in Weld County also tested positive for the disease in November.

And in October, a black bear in Huerfano County was euthanized after a wildlife officer saw it having seizures. A necropsy on its frozen remains revealed bird flu.

It is unclear if the black bear represents an isolated case or if the disease could now be spreading across populations of black bear in Colorado. 

CPW said the current strain of bird flu has been found in skunks, foxes, black bears, bobcats, coyotes and other animals around the country, and it’s also been found in marine mammals.

“The number of mammal cases is low compared to the number of cases we’re seeing in birds,” Duncan said. “It is not nearly the problem or the scope that the infections are in wild birds, but we’re keeping an eye on both of them.”

The virus was first confirmed in wild geese in the northeast part of the state in March 2022 but is now widespread, including in wild and domestic flocks in the Denver metro area. It’s most common among geese in Colorado, along with raptors and other scavenging birds that eat geese.

Public urged to keep distance from wildlife

Tests are pending on more animals in Colorado that are suspected to have contracted the virus, CPW said.

“CPW routinely investigates reports of sick and injured wildlife and is always interested in hearing from the public if they encounter something that doesn’t look quite right,” CPW Area Wildlife Manager Brandon Diamond said in a statement.

Signs of this strain of bird flu include seizures or circling, weakness or lack of response to human presence and organ damage, like encephalitis, hepatitis and pneumonia.

It’s rare, but bird flu can also infect humans, according to CPW. People are urged to keep their distance from wildlife, not to handle sick or dead birds and to take extra care to protect pets.