Authorities are looking for whoever is responsible for shooting blow darts at wildlife in Pelham Bay Park in the Bronx.
Nine animals, including a Canadian goose, a squirrel and two ring-billed gulls, have been shot over the past several years.
Two of the birds were found dead and two had to be euthanized.
"It's a terrible thing and animals should not be harassed like that," said Geoffrey Croft, of the watchdog group NYC Park Advocates.
The group says the blowguns apparently can be purchased at local grocers.
The darts are the size of a pen.
Park rangers are on the lookout for the possible attacker. Authorities have no leads on who might be terrorizing the animals.