The new strain of highly pathogenic bird flu that has forced the destruction of nearly 25 million domestic fowl across the United States is also spreading rapidly among wild bird populations in Minnesota, Wisconsin and the Dakotas.
The disease appears to have spread rapidly north from states like North Carolina and Florida, riding on infected migratory birds, especially waterfowl.
Minnesota has already seen several cases of Canada geese, mallards and bald eagles with the disease, beginning in late March and increasing this week.
In North and South Dakota, Iowa and Missouri, snow geese died by the dozens. Snowy owls, hawks, swans, crows, vultures, cormorants, pelicans and other waterfowl have also perished, according to the US Department of Agriculture.
More than 40 wild bird species in 30 states have tested positive so far.
“This strain (of bird flu) appears to be truly devastating to wild birds, especially waterfowl and creatures that eat waterfowl,” said Michelle Carstensen, wildlife health group leader and wildlife veterinarian for the ministry. of Minnesota Natural Resources.
Carstensen said wildlife health experts across the country and in Canada receive daily reports of dead birds as the migration moves north. On Thursday, Minnesota recorded 24 confirmed cases in wildlife across 10 counties.
“We don’t yet know what’s going on with this H5N1 strain that’s causing it to spread so quickly in wildlife. In 2015, when H5N2 really hit the poultry industry in Minnesota, we searched the entire state carefully and just couldn’t find any. We found it in a bird, a Cooper’s hawk. … It’s clearly a completely different situation now,” Carstensen said. “It’s a big wildlife health issue. … What impact could it have on wildlife populations, like will it reduce the population of geese, we don’t know yet. That is just beginning.
NO SONGBIRDS OR WILD TURKEYS YET
While some wildlife experts have suggested owners take their feeders down to help prevent the spread of disease among songbirds, so far no songbirds have been reported with the disease in any state.
“For some reason, they (the songbirds) just don’t seem to be sensitive to it,” Carstensen said. “But it could happen.”
Wildlife health experts say wild birds can be infected with H5N1 and show no signs of illness. But some wild birds show neurological impacts from bird flu, such as tremors or convulsions, or become weak and flightless.
Wild birds are thought to be the likely route for the disease to spread to domestic poultry, which has caused the destruction of millions of birds in Minnesota and Wisconsin, driving up the price of eggs and chicken in the grocery stores.
“And this time we’re seeing it in backyard (poultry) flocks, unlike 2015, where we didn’t really see it at all,” Carstensen noted. “Probably because it’s so prevalent in waterfowl.”
So far, the disease has also spared upland birds, such as wild turkeys and pheasants.
“Upland birds like the wild turkey have behaviors and prefer habitats that make them less likely to encounter avian influenza viruses in the wild,” the Wisconsin Department of Natural Resources noted when announcing the disease was arrival in the state.
Carstensen said the disease hasn’t yet been discovered in Minnesota wild turkeys either, but it might be possible. She asks spring wild turkey hunters to report any dead turkeys, eagles or other birds they find, especially if they show no obvious signs of trauma.
The most recent strain was confirmed in Europe last year, then in Newfoundland, Canada, then quickly reached the southeast coast of the United States, where many species of migratory birds spend the winter .
LOW HUMAN RISK
The United States Centers for Disease Control and Prevention say the risk for humans of contracting the disease is very low.
“Based on available epidemiological and virological information on these viruses, the CDC believes that the health risk to the general public from current H5N1 avian influenza viruses is low. However, some people may have occupational or recreational exposures to birds that put them at higher risk of infection,” the CDC notes on its website. “Infected birds shed bird flu viruses in their saliva, mucus and feces. Bird flu infections in humans are rare; however, human infections can occur when enough virus enters a person’s eyes, nose, or mouth, or is inhaled.
Cooking wild game meat to an appropriate temperature, at least 165 degrees, would kill the virus in any poultry, experts note. The United States Department of Agriculture suggests that hunters and anyone else handling wild birds wear rubber gloves when handling wild game, for added safety.
REPORT DEAD BIRDS
The Minnesota DNR asks that you report the discovery of any group of dead birds at a location with no obvious cause of death—or any diseased or dead waterfowl or raptors, such as eagles—to your local DNR wildlife office or by calling the DNR Information Center at 888-646-6367.
In Wisconsin, you can report dead or sick birds to the DNR Wildlife Hotline by emailing email@example.com or leaving a voicemail for a return phone call at 608-267-0866.