America’s national bird is facing a potential crisis in one state.
Bald eagles are dying in Utah, stricken by an illness as yet unidentified by veterinarians. In December, at least 16 bald eagles are known to have died in the state. An official at the Utah Division of Wildlife Resources called the situation “very unusual,” the Washington Post notes.
Bald eagles that have died all appear to suffered from tremors, seizures, wing paralysis and weakness. While up to 40 bald eagles can die during any given year, experts say that injuries account for almost all of those deaths.
Symptoms exhibited by the bald eagles who have died resemble those shown by animals infected by West Nile Virus, but that disease is typically spread by mosquitos that are uncommon during winter months.
Utah provides a winter-time home to as many as 1,200 bald eagles, but very few actually nest there year round.
Wildlife experts are studying bald eagle bodies that have been collected and are consulting with the U.S. Geological Survey’s National Wildlife Center. They do not suspect lead poisoning in the bald eagle deaths.