'Getting a little strange': Unexplained jump in number of crows, merlins dying in Winnipeg, rehab centre says

A wildlife rehabilitation centre says an unusual number of crows and merlins are dying in Winnipeg this year, and staff there can't figure out why.

So far this month, the Prairie Wildlife Rehabilitation Centre has lost roughly 50 crows and 30 young merlins -- a type of falcon -- who came into the centre with unusual and unexplained symptoms, said Lisa Tretiak, president of the centre.

"Our crows are not having any other problems. We're not looking at broken bones," Tretiak said.

"They're looking almost healthy but then having these sort of seizures and [are] unable to stand, or they don't call, they're not vocalizing."

At the same time, one of their volunteers has been finding young merlins, usually just learning to fly, who exhibit similar — but not identical — symptoms, Tretiak said. The young merlins often appear to be starving, and many have white tongues, which is not common to the birds.

The centre has also seen an uptick in public reports of dead or dying birds, which Tretiak said have been made from all over the city.

"We don't normally see this large number [of birds] coming in," she said.

"And just the reports of people calling us, saying 'there's lots of dead crows on our street' — we just sort of said, 'This is sort of getting a little strange.'"

Symptoms, numbers unexplained

Tiffany Lui, animal coordinator for Wildlife Haven Rehabilitation Centre in Ile-des-Chenes, Man., said it's not uncommon for the centre to hear about or treat young birds that don't make it to adulthood.

But she said her centre has also seen an increase in the number of sick or dying crows in the past couple of weeks, although their symptoms have been different from what Tretiak described.

"They're in, I guess, not the best condition. They're usually lethargic, a lot of the times starving … even for adults, as well as the juveniles," she said. "Some of them we've been managing to reverse that, get them healthy again and back out the door. But there also have been quite a number that have been basically coming in beyond our abilities to help out."

Tretiak said she doesn't have a clue what could be causing the deaths.

"Typically, one of the common viruses that we would think is West Nile," she said. "However, what's confusing us is that the mosquito population has not been extraordinary this year. It just is a lot of animals not making it for having very little mosquitoes."

Staff at her centre also speculated about poisoning, but Tretiak says that doesn't make sense, either, because the birds haven't been isolated to a single area of the city.

Public asked to report sightings 

At first, staff weren't as concerned about the reports, because they thought the birds' poor health could be related to Winnipeg's recent heat wave, Tretiak said.

But the sick crows have been coming in in otherwise good health — not showing signs of dehydration, starvation or lethargy as she would have expected — and she's still not sure why the young merlins' parents appear to have stopped feeding them.

The centre has put out a call for the public to report dead or dying merlins and crows in their neighbourhood directly at  (204) 510-1855, so staff can collect the bodies and hopefully send them to be tested. That process is still being ironed out, Tretiak said.

"This is sort of something that we can pass along to other agencies, saying, 'It's just a little strange for us,'" she said.

"Maybe it's normal, but it might be something we want to look into just to identify if there's something, a new virus coming into the province that we should be aware of."