Avian flu and you: How you can help protect local bird populations

News | Feb 21, 2023

Rick Spitzer

Does it seem like there are fewer birds in your neighborhood? Though your observations may be personal accounts rather than facts or research, they are common. The amount of birdseed consumed at my feeders is considerably less than in previous years. Is it pollution? Is it climate change? Is avian influenza responsible? Should you not put out bird feeders?

Avian influenza is caused by a virus that infects birds. It is most common in waterfowl and shorebirds. These birds can carry the virus without showing any signs of disease. Infected birds shed the bird flu virus through their saliva, mucous and feces.

**Finding one dead bird, like this yellow rumped warbler, is not an issue. Multiple dead birds is a cause for concern.**
*Rick Spitzer/For the Vail Daily*

A new strain of avian influenza appeared in the spring of 2021 and winter of 2022 in the United States and Canada. It is considered a highly pathogenic strain that causes more severe disease and higher mortality in some bird species, particularly waterfowl and domestic poultry.

It is causing higher mortality in wild birds, particularly in snow geese, raptors, and vultures. Typical symptoms include swimming in circles, moving slowly, incoordination (may appear drunk), and head tilt or the inability to lift the head. Most affected birds are seen on the ground, but occasionally sick birds may be seen flying low and alone.

The current strain does cause disease in many species including swans, gulls, geese, grebes, pelicans, raptors, vultures, cranes, some species of ducks, and other game bird species. This strain has also caused mortality in several mammal species, especially in skunks and foxes that prey on birds.

**Song birds do not seem to be as likely to contract avian flu as poultry and waterfowl.**
*Rick Spitzer/For the Vail Daily*

Colorado Parks and Wildlife recently identified cases of highly pathogenic avian influenza in Colorado wildlife. A black bear from Huerfano County, a skunk from Weld County, and a mountain lion that died in Gunnison County were recently confirmed to have avian influenza. Tests by Colorado State University in Fort Collins and the National Veterinary Services Laboratory in Ames, Iowa, found the disease in these animals.

The virus has a near 100% mortality rate in poultry and the only way to deal with infected poultry is to euthanize entire flocks. This is true even if the virus is detected in only one bird in the flock. The Colorado Department of Agriculture’s state veterinarian stated that across the United States, more than 52 million birds have been lost in the largest avian flu outbreak in U.S. history.

**Water fowl are migratory and can be more easily exposed to avian flu in the flocks they fly with.**
*Rick Spitzer/For the Vail Daily*

In Colorado, 4.7 million domestic poultry birds, 85% of our total table egg-laying population in the state, have died in the outbreak this year. Egg shortages and an increase in prices of broiler chickens, and turkeys will continue to increase until the avian flu stops spreading.

Around 350 species of North American birds migrate from breeding grounds in the United States and Canada to their wintering grounds as far south as Central and South America. During migration, they tend to travel in large groups for their trip and then congregate in their wintering grounds. A gathering of birds can spread disease easily.

**Birds, like this secretary bird, in the Denver Zoo are kept indoors so that they are less likely to contract avian flu from wild species.**
*Rick Spitzer/For the Vail Daily*

Zoos have experienced problems with avian flu when infected wild birds enter the zoo enclosures. At the Denver Zoo, a Brazilian teal and a Barrow’s goldeneye that died tested positive for the bird flu. Because of the threat this poses to birds in zoos across the country, many birds have been moved into safe indoor areas and will not be in outdoor habitats during this infectious period. Animal care staff have implemented many other protocols to protect birds until the risk to animals subsides.

What about the birds in your neighborhood? Is it still safe to feed birds at your feeders?

Wild Birds Unlimited has been monitoring the Avian flu outbreak in the United States and Canada. They do not believe that there is a need to stop watching, feeding, or attracting feeder birds to your yard because of avian flu. However, they do not recommend feeding or attracting waterfowl. It appears that the backyard birds that are at our feeders are less susceptible to avian flu and much less likely to become a source for the virus. Clean and sanitize your bird feeders, bird baths, and hardware, if you see or suspect a sick bird.

**Wild Turkeys do not migrate so, unlike other poultry, are less susceptible to contracting avian flu.**
*Rick Spitzer/For the Vail Daily*

Waterfowl hunters should take steps to minimize the risk of spreading the virus. Human infections with bird flu viruses can happen when the virus gets into a person’s eyes, nose or mouth, or is inhaled. There is a minimal risk of human infection. Human infections are most likely to happen in people directly exposed to infected birds or contaminated environments.

Hunters should not handle or eat sick game and are advised to monitor their health for any signs of flu-like symptoms within a week of handling birds. The Colorado Parks and Wildlife and the Colorado Department of Agriculture have documents that contain recommendations for individuals who handle wild birds. Poultry, like turkeys, are susceptible to bird flu, but wild turkeys do not migrate and are therefore less likely to contract the virus.

**Trumpeter Swans migrate hundreds of miles and may spread avian flu because of contact with birds in many areas.**
*Rick Spitzer/For the Vail Daily*

What should you do if you find sick or dead birds? If you find three or more dead wild birds in a specific area within a two-week period or if you see live birds showing clinical signs of disease, you are asked to contact your local Colorado Parks and Wildlife office. CPW will not be able to respond to all calls and is focusing responses based on surveillance and management priorities.

The problem of avian flu may become even worse. According to the Montana State Department of Fish, Wildlife & Parks, three grizzly bears tested positive for the highly pathogenic avian influenza virus and were euthanized after they became ill. Montana also documented cases of HPAI in a skunk and a fox last year, and the virus has been seen in raccoons, black bears and a coyote in other states.

Bird watching and bird photography are great activities many people enjoy. Birds are essential for the environment. They are pollinators and help disperse the seeds of many plants, especially native plants. Birds keep populations of insects, rodents, and other small animals in check. That ensures a healthy ecosystem.

**Birds at bird feeders, and bird baths, like these brown headed cow birds, are more likely to come into contact with the saliva, mucous, and feces of other birds.**
*Rick Spitzer/For the Vail Daily*

Like the canary in the coal mine, birds are indicators of what may be happening in our environment. Avian flu, pollutants, and climate change are impacting birds and now some other populations. We need to do all we can to support this group of wildlife.