For the endangered Mexican wolf, this is a population explosion. 

Eight rare Mexican wolf pups have been born at a preserve in the New York City suburbs, a development that could aid the federal program that has reintroduced the endangered species to the wild.

The Wolf Conservation Center in South Salem announced Monday that five males and three females were born Sunday to the Mexican wolves known as F749 and M740.

Eight new pups in a world population of around 366 is a 2 percent increase.

- Peter Siminski, coordinator of the Mexican wolf program for the U.S. Fish and Wildlife Service.

A video on the center's website showed a furry gray mass of tiny pups, some of them making small noises. The online announcement said the pups were no bigger than a potato.

"It's always a good day when we learn of the birth of an endangered species," said Peter Siminski, coordinator of the Mexican wolf program for the U.S. Fish and Wildlife Service. "Eight new pups in a world population of around 366 is a 2 percent increase."

Siminski said there are an estimated 42 Mexican wolves in the wild and 324 in captivity.

The wild wolves are kept along the New Mexico-Arizona state line under the federal program that reintroduced them to the wild in 1998.

To maintain genetic diversity, that population is restocked from pups born to the wolves kept in captivity, including those at the Wolf Conservation Center, which is 45 miles from midtown Manhattan.

"This is an important accomplishment for the Wolf Conservation Center because of all the careful planning and preparation that goes into the birth of a litter," Siminski said.

If any of the new pups are selected for introduction to the wild, it won't be soon. Siminski said chosen wolves would likely be sent to a prerelease facility, paired with opposite-sex wolves and allowed to raise pups themselves before being sent out.

The parents were selected as a breeding pair under the federal program's genetic standards designed to limit inbreeding.

"These pups are not only adorable, they're also great contributions to the recovery of their species," Monday's announcement said. It said all eight appeared to be healthy.

Like their parents, the pups won't be named but will receive numbers, plus M for the males and F for the females. Maggie Howell, managing director of the preserve, said last year that resisting the urge to name the wolves is part of the effort to limit human interaction, which can give them a better chance in the wild.

Howell said Monday that the conservation center won't help the parents raise the pups.

"Hopefully one day these animals will get an opportunity to live in the wild so we'll be doing very little with them in order to best equip them for a wild future," she said.

The wolves are not on public exhibit. But various webcams, available on the website, are used to spy on them, and staffers strongly suspected in recent weeks that the wolves were expecting.

Three other pairs at the Wolf Conservation Center — one Mexican wolf pair and two red wolf pairs — were also designated as breeding pairs.

"We'll remain glued to our eight webcams to watch the new parents care for their young and the arrival of more potential pups in the coming weeks," the announcement said.