A bird-conservation group filed a federal suit Thursday, claiming New York has violated the Endangered Species Act by allowing feral cats to live at Jones Beach, where they threaten endangered shorebirds.

The suit, filed in U.S. District Court for the Eastern District by the American Bird Conservancy, names Rose Harvey, commissioner of the New York State Office of Parks, Recreation and Historic Preservation, and alleges that the state has allowed local residents to create and maintain structures at Jones Beach State Park to house feral cats, despite the presence of nesting piping plovers — a tiny shorebird that is listed as an endangered species in New York and a threatened species federally.

The presence of cats “likely results in a significant reduction in the feeding of nesting chicks and an increased likelihood of nest failure by an order of magnitude,” the suit reads.

The suit claims that “at least two feral cat colonies” exist at Jones Beach — near the West Bathhouse and at Field 10 — and that the cats have been seen on the beach near the birds’ nesting areas.

While the Washington, D.C.-based nonprofit says the state in a letter last year acknowledged both the presence of the cats and the possibility of their presence harming the piping plovers, “the parks office has taken no effective action to remove the cats.”

“The park has placed ‘no pets’ signs at its parking lots, yet allows cats to be fed in the same areas,” Mike Parr, the group’s chief conservation officer, said in a statement. “It makes no sense to prevent one but allow the other.”

A state parks spokesman on Thursday said the department could not comment on pending litigation.

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There were 30 feral cats living at Jones Beach in 2006, the parks department has said previously.

There are about 800 breeding pairs of piping plovers on the Atlantic Coast, with about 200 of those in New York, according to the New York State Department of Environmental Conservation. Within the state, the birds — which grow to about 5 1/2 inches long, primarily are found on Long Island, according to the DEC.

Nesting piping plovers are protected with fencing, signage and exclosures — netting designed to keep predators away from the nests.

The suit seeks a court injunction that would keep the state from allowing the feral cats to reside at Jones Beach and require the removal of the cats.