Iconic Sandhill cranes face mass die-off in bird flu outbreak
More than 1,500 iconic sandhill cranes have been killed by bird flu in Indiana, officials say, the latest development in the spread of the highly infectious respiratory illness.
Volunteers in masks and gloves have been collecting the 15-pound birds from shorelines, marshes and ponds, hoping to reduce the risk to pets and children. Data analyzed by Paste BN indicates this may be the single largest bird die-off caused by avian flu in at least three years.
"I've never seen anything like this. One or two dead birds, yes, but not hundreds. I literally saw 45 of them die in front of my house, out of the window," said Sean Leone, 48, who lives on Upper Fish Lake in Laporte County, Indiana, about 20 miles west of South Bend. "It's sad to watch."
Sandhill cranes are the most numerous of the crane species in the United States, drawing tens of thousands of tourists annually to festivals and bird-watching excursions across the Midwest. The outbreak also raises fears about the potential threat to the nation's endangered whooping cranes.
Though not every dead crane is being tested for bird flu, Indiana state officials confirmed that was the cause, Leone said. He said dozens of other geese and ducks have also been killed.
Migratory sandhill cranes spend winters in warm places like Mexico and Texas and then make their way as far north as Alaska, stopping off along the way to bulk up at grain and cornfields. Sandhill cranes are found year-round in Louisiana, Florida and Georgia.
Scientists say migratory flocks, especially of wetland birds, have been responsible for helping to spread the virus. U.S. and Canadian officials tracked the arrival of this outbreak to gulls in Newfoundland in November 2021. Outbreak maps in 2022 showed the flu moving along the migratory flyway over the Missouri River basin.
Avian flu has killed millions of birds
Present in the environment for decades, avian flu routinely kills wildlife, including waterfowl, and is responsible for helping drive up the cost of eggs because once the virus enters a flock, they must all be put to death.
Since the beginning of the outbreak, roughly 144 million commercially grown chickens have been affected and 18.6 million turkeys, based on U.S. Department of Agriculture data. By far the largest percentage of infected chickens have been the table egg layers, at more than 124 million. But millions of commercially grown ducks and gamebirds, as well as backyard poultry, also have died or been put to death, affecting more than 166.1 million domestic birds total.
The virus has been detected in all 50 states and Puerto Rico. It has been detected in 40 wild mammal species in 36 states, killing bears, harbor seals, foxes, squirrels and skunks, among other creatures.
Last March, the virus was detected in dairy cows for the first time, according to federal officials, prompting new testing to reduce the risk that contaminated milk might make people sick. Since then, testing has shown the virus present in dairy herds in 17 states, though pasteurized milk, which is what most Americans consume, is considered safe.
The virus is responsible for at least one human death in the United States, and experts have long worried it may mutate to become more dangerous to people.
Leone said he and other volunteers have been using a rowboat to collect dead birds, hauling them aboard to be double-bagged in trash bags and disposed of in a rented Dumpster. State Department of Natural Resources officials checked out the deaths but said they don't typically pick up dead birds, prompting Leone to organize a community cleanup.
"The DNR said they weren't worried about infecting a fish or anything in the water … but to me the biggest concern was leaving them there knowing they have a virus," he said. "Knowing how many kids and pets there are out here, I just didn't want them getting exposed to it."
Concern for whooping cranes
Dr. Diana Boon, the director of conservation medicine for the Wisconsin-based International Crane Foundation, said the Sandhill crane deaths also highlight a greater concern: the risk to endangered whooping cranes. Though there are an estimated 827,000 sandhill cranes in the United States, there are as few as 834 whooping cranes globally, including those in captivity, the foundation said.
The sandhill and whooping cranes often share habitat, living alongside ducks and geese that are also getting infected and dying, Boon said. The species share portions of their migratory pathways in the eastern U.S.
"They are sharing habitat and wetlands with lots of other waterfowl," she said. "If it gets into a small number of (whooping cranes), that's a large percentage of the population."
Other countries have seen mass crane die-offs caused by bird flu, from Israel to Japan to Hungary, where an at least 10,000 and possibly 20,000 Eurasian cranes died in winter 2023.