Bird flu has killed at least four bald eagles in Colorado and threatens hundreds of other rare raptors and wild birds, as Colorado agriculture and wildlife officials struggle with an outbreak they call the worst in national or state history. 

Colorado’s current bout with avian influenza has already forced farmers to mass slaughter more than 4 million chickens from egg operations, and now wildlife officials worry the highly infectious disease may have contributed to a 15% to 20% drop in successful eagle nesting this year. 

Bird experts fear for dozens of year-round bald eagles in the northeastern Colorado corridor of reservoirs and wetlands along the South Platte River, after a mass snow goose die-off killed more than 2,000 birds near Julesburg/Jumbo Reservoir. Waterfowl pick up the disease from saliva, mucous and feces of other birds. Raptors and other carrion birds also spread the disease feeding on carcasses undiscovered by wildlife officials or neighbors. 

Raptor centers like Rocky Mountain Raptor Program in Fort Collins are taking in a steady stream of great horned owls and red-tailed hawks dying from the fast-acting virus. Staff are donning Tyvek protective suits and other PPE in an effort that is more hospice than rescue. 

State wildlife officials assume there are more dead bald eagles than the four confirmed so far in 2022 by tests of carcasses. With fewer than 300 nesting pairs of bald eagles making their homes along Colorado’s waterways, losses from any new threat to the more rare raptors quickly raise warning levels. 

Read more on ColoradoSun.com.