Researchers say virus likely killed P.E.I. crows

The hundreds of crows found dead in a Charlottetown park earlier this winter likely died from a viral outbreak, according to researchers in Prince Edward Island.

One dead crow was found to have contracted corvid orthoreovirus, which causes severe inflammation within the small and large intestines of infected crows and can quickly lead to death, Laura Bourque with the Atlantic Veterinary College at the University of Prince Edward Island said in an interview Wednesday.

She said it’s highly likely the reovirus is to blame for all the deaths.

“We haven’t seen it here very much at all, but that’s not to say that it is surprising, because it happens elsewhere in Canada and in the (United) States,” she said.

“We’re pretty sure at this point that that’s what’s going on with the downtown crows.”

Bourque, who also works with the Canadian Wildlife Health Cooperative, said the team investigating the deaths is trying to see whether the virus can be detected in the other dead birds that were collected for study.

The virus, she added, is easily spread through feces and other secretions while crows are roosting in densely populated areas during the winter. She said corvid orthoreovirus is a relatively common cause of crow mortality in northeastern North America.

Earlier this winter, local residents started noticing the dead birds in Charlottetown’s downtown.

There isn’t much for researchers to do as the disease is fairly untreatable, Bourque said, adding that the outbreak will continue to be monitored as it evolves. Anecdotal evidence from residents in the area suggests that fewer crows have been found dead in recent weeks, she added.

Once the outbreak dies down, she estimates the crow population in Charlottetown will rebound within the next two years.

Residents should take care to not handle bird carcasses, she said, and report any dead birds to regional wildlife authorities. The chance of the disease passing from crows to humans is very low, Bourque added.

This report by The Canadian Press was first published March 2, 2022.