Hundreds of pigeons are dying in California, officials say. What’s killing them?

Residents are finding hundreds of dead and dying birds in some parts of California, and a waterborne parasite is to blame, state wildlife officials reported.

A parasitic disease called avian trichomonosis is killing band-tailed pigeons, which are native to California, the Department of Fish and Wildlife said in a news release.

Officials estimate 200 to 300 birds have died of the disease this winter.

Band-tailed pigeons are secretive and nomadic, congregating in central and southern California in winter, the release said. They form large flocks and seek acorns for food.

The birds are highly susceptible to avian trichomonosis, which is caused by a parasite found in water in bird baths, fountains and horse or cattle troughs, officials said.

Infected pigeons develop lesions in their mouth or throat, leading to death by suffocation or starvation, the release said.

“Residents can help reduce disease transmission among birds by removing bird feeders and bird baths and emptying fountains while the pigeons are in their area,” the agency said.

Dispose of dead birds by using gloves to put them in a plastic bag, which can then be placed in the trash, officials said. Wash hands thoroughly with soap and water.

This story was originally published February 27, 2023 at 10:05 AM with the headline "Hundreds of pigeons are dying in California, officials say. What’s killing them?."