Plymouth officials are working with the state to determine whether dozens of dead birds found at Billington Sea were killed by avian flu.
Karen Keane, the town’s director of public health, said about 70 dead geese, swans, and ducks were collected from the 269-acre pond Sunday morning. The operation involved the Massachusetts Department of Environmental Protection, the state Division of Fish and Wildlife, the Cape Wildlife Center, and the Clean Harbors environmental company, as well as Keane.
Other birds, visibly suffering, were euthanized at the scene.
“It’s a sight,” Keane said. “It’s very hard to actually see it.” She said Clean Harbors took birds away. They will be tested for H5N1, otherwise known as avian influenza or bird flu.
“We’ll await the results of the testing to find out if we’re dealing with avian flu,” she said.
Meantime, Keane warned residents to keep their pets away from dead birds. She noted that many people were walking their dogs in the Billington Sea area over the weekend.
Scavengers that pick up dead birds- such as crows – would likely get sick and die, she said. Cats are particularly susceptible to avian flu.
“If you have outdoor cats, make them indoor cats for a little while,” Keane urged.
There is reason to believe that the virus is already present in Plymouth.
State ornithologist Andrew Vitz told town officials Saturday that a dead goose found in Plymouth last week is “highly suspected” of carrying H5N1. Vitz did not immediately return a call seeking comment.
Casey Kennedy, the town’s communications coordinator, said it could take several days for conclusive test results on the goose.
Keane explained that only one lab in the US can make a positive determination that a bird has H5N1. Other labs can only make what is called a non-negative determination or a positive presumption, she said.
“Our goose did have a non-negative result,” she said. “Now it’s going for further testing. That’s why there was concern that we may be having an avian flu situation here in Plymouth.”
In the meantime, state officials have advised the town to assume that the bird died from the virus, Kennedy said.
In addition to preventing pets from coming into contact with dead animals, Plymouth’s Department of Health advises people to stay away from all sick or dead wild birds, poultry, and other animals. They should also avoid contact with any surfaces contaminated with saliva, mucus, or feces from birds or other animals suspected of having avian flu.
Keane urged people with backyard flocks to disinfect equipment that they might lend to neighbors who also have flocks, and to wear gloves when handling birds.
The avian flu virus spreads through direct contact between birds as well as contact with manure, egg flats, crates, clothing, shoes, and hands.
“Warm water and soap is the best defense against so many things and in this particular case it’s also the same for people who do have poultry in their backyard,” Keane said. “After taking care of your poultry – whether it’s feeding them or cleaning out their coop – after you’re done, you use soap and water or a hand disinfectant.”
The town’s Health Department said all backyard poultry should be corralled and not allowed to run free range.
It’s “really important to keep an eye on the flock,” Keane said.

The U.S. Centers for Disease Control and Prevention says that handling birds sickened the virus is unlikely to infect people, but the agency advises anyone experiencing flu-like symptoms within 10 days of handling sick or dead birds to seek medical attention.
Residents should report dead animals to the Plymouth Health Department at 508-322-3339 and to the Animal Control Officer at 508-888-1186. You should not pick up a dead animal yourself, even with gloves.
Large-scale die-offs or unusual behavior among wild birds should be reported to the U.S. Department of Agriculture at 866-487-3297.
The state has been dealing with an ongoing outbreak of H5N1 in birds since 2022, according to the Massachusetts Department of Agricultural Resources.
In March 2024, the department killed an entire backyard flock of poultry in Essex County because birds exhibited signs consistent with avian flu and samples tested positive for the disease.
As the virus is most prevalent among waterfowl, the state advises owners of backyard flocks to eliminate standing water and prevent domestic birds from having access to ponds, streams, and wetland areas that attract wild waterfowl.
Last week, dead birds were collected in Boston, and others have recently been found in other towns on the South Shore, Keane said.
She said officials are not aware of any infected livestock in Massachusetts – other than birds – nor have any human cases of infection with H5N1 been reported in the state.
Outbreaks of H5N1 have been reported among dairy cattle and poultry in other states, and human cases have been reported – primarily but not exclusively among people working with animals. Most people infected in the United States have experienced mild symptoms, but a person in Louisiana who worked with backyard poultry died earlier this month. The victim, who was over 65 years old, had underlying medical problems, officials said.
Fred Thys can be reached at fred@plymouthindependent.org.