Your Bird Flu Questions Answered

28 February, 2025 – CAPE COD, MA – The avian flu is still widespread in Massachusetts and Cape Cod, but how does it spread? What does it mean for the wild bird populations? Should you take down your bird feeders? We asked Andrew Vitz, State Ornithologist, these questions and more.

What Is The Avian Flu?

The Highly Pathogenic Avian Influenza, HPAI or the avian flu, is a highly transmittable virus naturally carried by migratory birds, primarily water fowl. The new strain, H5N1, entered the U.S. in late 2021 and in 2022 the first infected wild birds in Massachusetts were detected on Cape Cod. It has spilled over onto domestic birds and dairy cattle, from which humans have caught the disease. There have been no known human cases in Massachusetts to date. Dairy cattle have been routinely tested in Massachusetts once a month since August last year. Only one poultry farm in the state – with 30 birds in Plymouth – had to be euthanized in late January 2025.

Where is the avian flu?

The virus is still widespread in Massachusetts and on Cape Cod, though the numbers of reported wild birds have declined. This can be expected when the weather starts

to warm up since viruses thrive in cold and wet climates, nevertheless, this current outbreak of H5N1 has been the biggest one to date. "We've had a colder winter than we've had in the last couple. We've had more ice, fewer areas of open water," says Andrew Vitz, State Ornithologist at Massachusetts Division of Fisheries and Wildlife. "So a lot of birds have been congregating in smaller areas, and that just facilitates the spread of the virus. We think that's why we're seeing this larger scale outbreak this year."

What Should The Public Do About The Avian Flu?

Despite declining numbers of cases among wild birds, the public guidelines remain the same. "People shouldn't be panicking," says Vitz but emphasizes the the public should keep a few things in mind. 

"Taking the precaution seriously when you are in an area where there have been sick and dead birds, one reporting to MassWildlife those reports so we can respond accordingly. (...) Keeping your dog on a leash, if you have a a domestic cat keeping it indoors." Vitz adds that cats are especially susceptible to the virus.

Should I Take My Birdfeeders Down?

One of the most common questions MassWildlife gets regarding the avian is: Should people take their birdfeeders down? Though Vitz says birdfeeders are currently not a big player in spreading the avian flu, that could change. MassWildlife's standing recommendation is always to stray away from feeders, especially seeds, since they attract other less welcome wildlife such as rodents.

"If you feed birds at a bird feeder, it just increases the chance for disease spread, and that includes high path influenza. The risk goes up if there are any domestic birds in the vicinity," Vitz says.

"We don't know how it's gonna play out going forward. Our recommendation is always to bring in your birdfeeders. There are other ways to attract birds."

In the wild the avian flu has mostly spread among Canada Geese, swans and other waterfowl.

Songbirds have been mostly spared, but Andrew says they are not immune.

"It does not seem to be moving much through the songbird community, but we know that they can get it. And mostly it's been in birds that have a tendency to pick on carcasses. So, crows have gotten it. Blue jays. (...) Things like chickadees will do the same thing."

How Are Vulnerable Bird Species Affected?

For vulnerable species like bald eagles the virus could pose a reason for concern. "That's what we're trying to figure out, how much of an impact it's having. The eagles will be easiest for us to determine that, we monitoring them closely. (...) So we'll be putting an extra emphasis on monitoring those eagle nests to get a better handle of is this affecting eagles at a population level," Vitz says. "The other thing is are they developing a resistance to it?"

The answers could indicate how other species are handling the virus as well. Some birds like mallards seem to be fighting the virus off much better than swans and geese. A sick bird can be spotted by unusual behavior. "It is a neurological virus. It affects the brain. What you see with sick birds is that they often are disoriented, they're stumbling around, they lose their ability to balance very well. Some of them are twisting their necks,  swimming in circles. And mortality seems to occur pretty quickly," Vitz says.

Are Backyard Flocks Safe?

According to Massachusetts Department of Agricultural Resources 138 million domestic birds have been impacted since 2022, leading to a rise in egg prices. Any flocks of under 3,000 birds count as non-commercial, there are several hundred backyard flocks in Massachusetts. According to MDAR, the state’s policy is to cover the costs of depopulations of commercial flocks.

All domestic poultry flocks on Cape Cod are backyard flocks. Owners are urged to keep their animals in an enclosure to limit contact with wild birds, and report any signs of illness to MDAR.

Can I still eat meat, eggs and dairy?

According to the Center For Disease Control and Prevention cooking beef, poultry and eggs all the way through kills the virus. For eggs and poultry meat that means an inner temperature of 165°F. Ground beef should be heated to 160°F and whole cuts of beef should reach 145°F then rest for 3 minutes. Pasteurized milk is safe.

Do not feed your pets raw poultry or raw pet food.