A whooping crane chick died from bird flu in September in Wisconsin. It's the first known death of a whooping crane to the disease.
A whooping crane chick died from highly pathogenic avian influenza, or bird flu, in September in Wisconsin, the first known mortality of the endangered species from the disease, according to the International Crane Foundation.
The 3½-month-old female chick was among eight young whooping cranes being reared at Horicon National Wildlife Refuge near Mayville, Wisconsin, as part of ICF's breeding and reintroduction program for the species.
It was slated to be released to the wild later this year along with the others in the 2025 cohort of captive-reared whoopers.
The chick died Sept. 18, according to ICF. Its cause of death was confirmed by testing at the Wisconsin Veterinary Diagnostic Laboratory in Madison.
"We are deeply saddened by the loss," Kim Boardman, curator of birds at ICF, said in a statement. "Each (whooping crane) is invaluable, not only to our organization, but to the survival of the entire species."
The H5N1 HPAI virus has circulated in wild and domestic birds in North America since December 2021. The disease, caused by influenza type A virus, is highly contagious and often fatal to birds, according to the Wisconsin Department of Agriculture, Trade and Consumer Protection.
It can be spread through contact among infected birds or their droppings as well as by equipment, clothing or footwear contaminated with the virus.
Waterfowl, including ducks, geese and swans, are known to carry and transmit the virus. The whooping crane chick likely contracted HPAI from a wild bird or through the environment, according to ICF.
The other seven whooping crane chicks being held at Horicon National Wildlife Refuge for fall release may have been exposed to the virus; however, none has shown symptoms and will remain under observation.
Since late 2021 HPAI has killed or caused the culling of tens of millions of domestic birds in the U.S. as well as killed an unknown number of wild birds.
In recent news, a commercial poultry farm in Jefferson County was forced to cull its flock of 3 million birds after tests confirmed the presence of HPAI, according to a Sept. 25 announcement from the Wisconsin Department of Agriculture, Trade and Consumer Protection.
The agency is working with the U.S. Department of Agriculture to contain the virus. The commercial egg-laying operation in the village of Palmyra has been quarantined to limit movement of the birds and spread of the disease.
The Jefferson County case was the state’s first detection of bird flu at a commercial facility since April. However, it's part of recent increase in cases of HPAI in the U.S., according to Darlene Konkle, DATCP state veterinarian. Twenty-three domestic flocks have been found with the disease in the last 30 days, according to the USDA.
Detections in wild birds are harder to track, but HPAI cases in September in Wisconsin include the deaths of American white pelicans in La Crosse County, a Canada goose in Dane County and a peregrine falcon in Pierce County, according to the USDA.
Other wild bird cases in September in other states include findings in a Canada goose in North Dakota, a black vulture in Pennsylvania and wood ducks in Iowa.
The uptick in HPAI cases is a source of concern for conservationists, including at ICF. In spring 2024 the disease killed more than 1,000 sandhill cranes in Indiana.
Whooping cranes are an endangered species with two migratory flocks, one of about 630 birds that breeds in Alberta, Canada, and winters in Texas and the Eastern Population that mostly breeds in Wisconsin and winters in several states to the south.
The Eastern Population is estimated to have 64 birds as of September 2025, including 36 females, 25 males and three of unknown sex, according to the ICF. Sixteen of the birds in the Eastern Population are wild-hatched and the balance are captive-reared.
As of Sept. 1 at least 54 of the whooping cranes in the Eastern Population were in Wisconsin, according to ICF. The locations of the other birds were not confirmed in the last month.
In recent years the Eastern Population of whooping cranes has suffered from very poor natural recruitment, or survival of wild-hatched chicks, as well as mortality of adult birds.
Only one chick that hatched in the wild in 2025 is still known to be alive and with its parents. As of September, the three birds were in Portage County, according to ICF.
Four other mortalities – all in August – were documented to adult whooping cranes in Wisconsin this year.
The birds included adult female 15-11 (the code is the number assigned to the bird followed by the two-digit year of its birth) found dead in Juneau County, suspected cause of death was predation; adult male 37-07 found dead in Juneau County, cause of death unknown; adult male 16-04 was found dead in Juneau County, suspected cause was predation; and adult male 4-17 found dead in Sauk County, likely due to a leg injury.
Boardmen of the ICF said the challenges being faced by whoopers, including the loss of the chick this month, has strengthened "our resolve to safeguard these cranes and the landscapes they depend upon."
The seven remaining whooper chicks are scheduled to be released in October, the time when wild whooping cranes in Wisconsin typically begin their southern migrations.
This article originally appeared on Milwaukee Journal Sentinel: Whooping crane chick died from bird flu in September in Wisconsin
Category: General Sports
