Thirteen bald eagles were found dead on the Eastern Shore of Maryland on Saturday, the biggest mass death of bald eagles in the state in 30 years, the Washington Post reported.
The eagles had no obvious signs of trauma, but authorities said they suspected poisoning. The birds of prey often scavenge on the carcasses of other animals, who themselves may have been poisoned, authorities told National Geographic.
Three of the birds found Saturday were considered “mature” eagles, with yellow beaks and brown bodies.
“Three mature eagles, the ones we all love that look like the national bird, are gone,” Candy Thomson, a spokeswoman for the Maryland Natural Resources Police, tells the Washington Post. “It’s sad that we have three eagles of mating ability that have been eliminated from our population.”
The carcasses of the birds will be sent to a forensic lab in Oregon, where authorities hope to determine the exact cause of death. They are also asking for help from the public, and offering a reward of $10,000 for information. (As readers of Atlas Obscura will remember, the U.S. has some very specific things that they ask of their citizens when someone happens to find a dead eagle even outside of this incident, namely you are legally obligated to send it to the Oregon center so they can catalog it.)
Other eagles have been found dead in Maryland in recent years after residents put out poisons intended for rodents, foxes, or other animals, and eagles scavenged. Eight were found dead in Maryland in the 1980s after suspected poisoning.
Bald eagles have not been an endangered species since 2007, but remain a protected species under the law, according to the U.S. Fish and Wildlife Service, making eagles illegal to be hunted or killed.