CITY HALL -- There's nothing stopping the city from snipping Staten Island bucks now.

Last week the state approved Mayor Bill de Blasio's $2 million plan to perform vasectomies on male deer to control the borough's herd.

On Friday the state Department of Environmental Conservation issued the city's contractor a license for surgical sterilization, tagging and radio collaring of Staten Island deer.

"We thank the DEC for approving this plan, so we can get straight to work on addressing the deer population in Staten Island in a safe, effective and humane way," de Blasio spokeswoman Freddi Goldstein said.

The DEC regulates wildlife and had to OK the city's plan. Spokesman Sean Mahar said that the DEC issued the permit so the city could "study their theory that the deer population on Staten Island can be controlled through the neutering of male deer."

The DEC doesn't recommend fertility control programs to mange deer populations because of their "limited effectiveness" and "inability to quickly reduce deer-human conflicts." Mahar said that such programs are also expensive.

"Where programs like this have been undertaken in other parts of the country, typically female deer undergo sterilization, as the sterilization of only male deer is likely to have little to no impact on the deer population overall since all male deer would have to be sterilized to get the population growth to zero," Mahar said. "In issuing this research permit for New York City to conduct this program on Staten Island, the state is not endorsing the effectiveness of the plan, merely allowing for another option to be explored to address the growing problem of overabundant deer is this community."

Fertility control is only permitted by the state as part of a research study, which is what the city proposed.

The Parks Department plans to sterilize hundreds of male deer over the next three years. Anthony DeNicola of White Buffalo is expected to start performing the vasectomies in September, in time for this fall's rutting season.

After walking the entire Island this summer, DeNicola identified 104 properties where he can reach the greatest number of male deer. Most are parks or city property, but a few are private developments.

The license allows White Buffalo to capture deer in both public and private lands on Staten Island, so long as the property owner or manager has given permission.

White Buffalo can bait deer with whole kernel corn or apples. The deer can be captured with drop nets, clover traps and tranquilizer darts.

Bucks would be driven, unconscious, to one of several parks facilities that would be prepped for the 15-minute surgery. Long-acting post-op pain medication must be given to them during the procedure.

The veterinarian performing the surgery must euthanize any deer that are injured and found unable to survive in the wild.

Bucks would be released back into parks following vasectomies, less than an hour after first being captured.

The effort is expected to eventually reduce the borough herd 10 to 30 percent annually.

All sterilized bucks will be ear-tagged and the city will also track some male and female deer with radio collars over the three-year research study. The Parks Department will use this to assess population dynamics, including deer mortality and birth rates.

Only 527 deer were found on Staten Island during the city's latest aerial survey of the herd -- 236 less than the last count two years ago and well below what officials expected.

The city said there's nothing to indicate the population has declined. Fewer deer may have been counted this year because the survey was conducted in warmer, less cloudy weather.

Bucks usually make up about 40 percent of any deer population.

An unrestrained and expanding herd can harm parks and private property, spread tick-borne illness and wander into roads more often, increasing the risk for deadly vehicle collisions.

Sterilization was chosen because the city believes Staten Island's herd is mostly growing through reproduction, not migration. Sterilizing males instead of females would be faster, cheaper and more humane.

Still, some wildlife experts have argued that the plan won't work because the city is ignoring basic deer biology and conventional herd management practices.

The above article was updated with a statement from the state Department of Environmental Protection. This article was also later corrected to clarify that the vasectomy effort is expected to eventually reduce Staten Island's deer herd 10 to 30 percent annually, not 10 to 30 percent overall.