Avian Flu: Take Down Feeders?

The following information is from Cornell Lab of Ornithology and is current as of January 3, 2025:

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six snow geese with white bodies and black wingtips fly against a blue sky
Migratory waterfowl, like these Snow Geese, are the most common carriers of avian influenza. Image by Linda Chittum/Macaulay Library.

Originally published April 2022. Updated through January 2025 to reflect further developments in the outbreak.

Many people are concerned about the outbreak of avian influenza, or bird flu, that began in 2022 and has affected domestic poultry, waterfowl, raptors, shorebirds, other species of birds, and some mammals in many parts of the world. Because the current strain (H5N1) causes heavy losses to poultry, it is referred to as highly pathogenic avian influenza, or HPAI.

Transmission of avian influenza from birds to humans is rare, according to Centers for Disease Control. To date, 66 people in the U.S. have tested positive for avian influenza. The Centers for Disease Control has a summary of current avian influenza testing and infection statistics, including guidelines and protective actions for members of the public.

Reports of Avian Flu in Birds

This particular strain of avian influenza virus affects a wide variety of wild birds, including hawks, eagles, falcons, owls, crows, vultures, shorebirds, game birds, seabirds, and especially waterfowl such as Canada Geese and Mallards (see list of species with HPAI detections, below). The virus is shed in the saliva, mucus, and feces of infected birds and is transmitted to other birds via ingestion or inhalation.

Because of the duration of this outbreak, its recent spread to mammal species, and widespread mortalities in some types of wild birds, there has been concern about whether it’s safe for people to feed wild birds. In April 2022 and March 2023, we checked in with Dr. Julianna Lenoch, who directs the USDA APHIS National Wildlife Disease Program, and we’ve compiled the following summaries of key points regarding HPAI, especially among songbirds and other feeder visitors. As of January 2025, there is no official recommendation for people to take down bird feeders because of the risk of avian influenza (see next section). The Centers for Disease Control has updates and recommendations about H5N1 in humans.

Low Risk of Avian Flu to Songbirds

There has been widespread transmission of avian flu to wild bird species including waterfowl and raptors. The virus has also been found in mammals that prey on dead birds. However, transmission to songbirds and other typical feeder visitors has been low (about 3% of all cases reported in wild birds), although this may change with increased testing or changes to the virus. That means there is currently a low risk of an outbreak among wild songbirds, and no official recommendation to take down feeders unless you also keep domestic poultry, according to the National Wildlife Disease Program. We do always recommend that you clean bird feeders and birdbaths regularly as a way to keep many kinds of diseases at bay. 

We also always recommend that you follow any recommendations put out by your state government, even in cases where that advice conflicts with ours. The CDC’s page on avian influenza in birds compiles additional helpful information and resources. 

How do we know songbirds are at low risk?

  • USDA APHIS has a strong, multiyear surveillance program that routinely samples wild birds, including flocks of songbirds (and other species such as Rock Pigeons and Mourning Doves that are often around humans), for the presence of avian influenza. Since January 2022 they’ve detected the HPAI strain in 9,877 wild birds (plus 1,040 captive birds), with 304 detections in wild songbirds (see below for a list of species). Latest info about the outbreak.
  • Avian influenza does not affect all types of birds equally. The “highly pathogenic” part of the term HPAI refers specifically to the severity of the disease in poultry, not necessarily in other bird species. For example, waterfowl often carry and transmit bird flu, and with the current strain they sometimes get sick or die. Raptors are much more sensitive to the disease. Domestic poultry are extremely susceptible to HPAI and spread the disease easily, leading to up to 100% mortality of affected flocks.
  • Songbirds are much less likely than waterfowl to contract avian influenza and less likely to shed large amounts of virus, meaning they do not transmit the disease easily. (See Shriner and Root 2020 for a detailed review in the journal Viruses.)
  • According to a separate study in the Journal of Wildlife Diseases, “…although passerines and terrestrial wild birds may have a limited role in the epidemiology of IAV [avian influenza A viruses] when associated with infected domestic poultry or other aberrant hosts, there is no evidence supporting their involvement as natural reservoirs for IAV.” (Slusher et al. 2014)
  • For these reasons, it is unlikely that bird feeders will contribute to an outbreak among songbirds.

If songbirds are at low risk, why are people who keep poultry advised to take down their bird feeders?

  • The main concern with songbirds is the chance that a rare individual might transmit an infection to poultry. This is a concern because poultry are so much more vulnerable than songbirds to HPAI.
  • The key intervention is to keep songbirds away from poultry; it’s less important to keep songbirds away from each other.
  • If you have a backyard poultry flock, these are the most important steps to take:
    (click for full info on these biosecurity measures from USDA APHIS)
  • As a secondary measure, USDA APHIS recommends for poultry owners to take down wild bird feeders or keep them well away from their captive flock
  • If you keep chickens or ducks, please see also latest information from the USDA Animal Plant and Health Inspection Service.  

If you keep nest boxes:

Avian influenza is only rarely transmitted to humans, according to the USDA. The Centers for Disease Control and Prevention considers the general public health risk from avian flu to be low. Nevertheless, our NestWatch project always advises good hygiene and highly recommends that people wear disposable gloves and/or wash their hands thoroughly after checking nest boxes. Most birds that use nest boxes are songbirds, which are at low risk for contracting or transmitting avian influenza. If you monitor waterfowl or raptor nests (e.g., Wood Duck, Common Merganser, Canada Goose, American Kestrel, Barred Owl), we suggest you wear gloves, change or wash gloves and disinfect equipment between nest boxes, wear a mask when cleaning out nest boxes, and change clothes and footwear before visiting any domestic poultry.

If you are a wildlife rehabilitator:

Wildlife rehabilitators should take precautions when accepting sick birds so that they don’t inadvertently introduce HPAI to the rest of their patients. Here’s further guidance for rehabbers, from USDA APHIS. Rehabbers in New York State are also encouraged to contact the Cornell Wildlife Health Lab for more information.

What to do if you find a sick or dead bird:

Avoid handling sick or dead birds. Instead, call your state wildlife health agency; they can determine cause of death and send the bird to the appropriate lab for testing. Additionally, keep pets (including pet birds) away from sick or dead wild birds.

  • Avoid contact with birds that appear sick or have died
  • Avoid contact with surfaces that have bird feces
  • If you must touch sick or dead birds:
    • Wear gloves and a face mask  
    • Place dead birds in a double-bagged garbage bag 
    • Throw away your gloves and facemask after use  
    • Wash your hands well with soap and warm water 

Bird flu is not a risk to food safety. Poultry and eggs that are safely handled and cooked to an internal temperature of 165°F are safe to eat. 

If you feel sick after having contact with sick or dead birds, contact your health care provider. 

Has Avian Flu Been Reported in Mammals?

There have also been reports of mammals such as red foxes, skunks, bobcats, fishers, and bears infected with avian influenza, likely from eating infected birds. Outside the U.S. avian flu has infected farmed mink and has caused losses at marine mammal colonies in South America. In March 2024 the USDA reported that avian flu has been found in cattle in several U.S. states. The CDC has additional information on avian flu in cattle and associated risks to humans.

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