A widespread outbreak of salmonellosis among songbirds, especially Pine Siskins and goldfinches, has claimed the lives of untold numbers of the birds in the last few months. To slow the spread of the disease, which is caused by salmonella bacteria, some state wildlife agencies and wildlife rehabilitation groups have encouraged people to take down their bird feeders and baths.
Birds in the Pacific Northwest and in southwestern Canada were hit hard earlier this winter, according to Dan Grear, a wildlife disease ecologist at the U.S. Geological Survey National Wildlife Health Center. More recently, outbreaks have been reported in the Carolinas, Georgia, West Virginia, Alabama, Texas, and several areas of California.
In February, the California Department of Fish and Wildlife said it had been “inundated with calls from residents who are finding sick or dead finches at bird feeders. Most reports have come from locations on California’s Central Coast, the San Francisco Bay Area, and Sierra Nevada communities.”
The agency’s statement identified salmonellosis as the cause and encouraged residents to remove feeders and baths. “Salmonellosis occurs periodically in Pine Siskins in some winters throughout their range,” said Krysta Rogers, an avian disease specialist with the California DFW. “When large numbers of Pine Siskins congregate, the disease can spread rapidly, causing high mortality. Most birds die within 24 hours of infection.”
In early March, on the other side of the country, the South Carolina Department of Natural Resources issued a similar statement, asking residents to take down feeders until early April, when Pine Siskins start to head north.
Jennifer Gordon of the wildlife rehab nonprofit Carolina Waterfowl Rescue said her organization has treated dozens of sick siskins, as well as House and Purple Finches and American Goldfinches. Most birds don’t respond to treatment and are euthanized.
Dan Grear of the USGS National Wildlife Health Center says salmonellosis infections in feeder birds are common in winter and early spring as the birds congregate to feed. “The number of cases during winter months in songbirds and in pigeons and doves that frequent garden bird feeders probably is significantly underreported,” so it is impossible to say how widespread the problem is right now. “The wildlife health community ends up looking at the really big obvious events, like in the Northwest this winter, but we don’t have the capacity to track down all the others.”
What you should do
If you have a bird feeder or bath and live in one of the affected areas, take them down for at least a few weeks or until local wildlife agencies say it’s okay to put them back.
Meanwhile, clean your feeders and baths to kill any potential bacteria. Grear and other experts recommend cleaning with a 10% household bleach solution (9 parts water:1 part bleach) and removing any spilled and potentially contaminated feed from under the feeder. Clean the feeders, bird baths, and any items contaminated with bird droppings in an outdoor space or in another area of your home that is not used for food preparation or bathing.
Salmonellosis can also affect people, pets, and livestock, making it even more important to remove potentially contaminated seed. Gordon says dogs have become sick after finding and eating lethargic or dead birds.
If you find dead birds in your yard, Gordon says you shouldn’t touch them with your hands. Use gloves and either bury them or double bag them and place them in the trash. Some state wildlife agencies have online forms for reporting dead birds or other wildlife.
If you live in an area where no cases have been reported this winter or spring, don’t assume the disease isn’t present. It may be worth contacting a local wildlife agency or rehabber to ask if it’s safe to keep feeders up. And keep a close eye on any siskins or other finches. When the birds are sick, they’re often hunched over, stand on the ground, or have discharge around the eyes.