This Town Wants to Put Its Deer on Birth Control

In Westchester County, hunting with firearms is prohibited and deer have no predators

In some places in the United States, deer are a serious problem. Perhaps nowhere in the country do people have such issues with deer as in New York, a state where since the 1980s the deer population has outrun and outbred human hunters.

One New York Times piece from 1988 estimates that in 1978 the state had 450,000 deer, a number that jumped to 800,000 in 1988. They explain that deer flourish in the suburbs, where there is plenty of grass and not that many hunters. They were even dubbed “yuppie deer” in that 1988 article. Decades later, the paper is telling a similar story—of deer roaming freely and dangerously around Westchester County, where hunting with firearms is prohibited and deer have no predators.

Without an efficient way to kill the deer, scientists and local activists have come up with a different plan. They’re hoping to inject female deer with contraceptives to keep them from having babies. The New York Times spoke with Dr. Allen T. Rutburg, the director of Tufts University’s Center for Animals and Public Policy, who has looked at wildlife contraceptives before:

Dr. Rutberg, whose center is part of Tufts’ Cummings School of Veterinary Medicine, has researched deer contraception for years. To date, his work has focused on self-contained areas, like Fire Island in New York and the fenced-in campus of the National Institute of Standards and Technology in Maryland. He has achieved reductions in population of 50 percent over five years. While Hastings is hemmed in by the Hudson River and the Saw Mill River Parkway, deer can easily head south from Dobbs Ferry or north from Yonkers, communities that are likewise overrun.

This isn’t the first time that wildlife managers have thought to use birth control on a booming population. In Africa, the push to inject elephants with immunocontraceptives has been controversial but effective. Here’s Scientific American:

Rather than simply setting a quota and culling the extras, immunocontraception could be a tool to allow land managers to control elephant populations in response to conditions on the ground such as food availability. “The approach now has to be much more dynamic and look at the influence the animals are having on the land,” says Robert Slotow, a biologist at the Amarula Elephant Research Program in Durban, South Africa. His team recently published a paper in PLoS ONE describing how scientists might be able to use immunocontraception—a vaccine that gets the body to make antibodies that target sperm receptors on the surface of the egg cell. Slotow and his team outlined an immunocontraception schedule that would halt the growth of herds in a South African park and even out their population structure.

The deer contraceptive would work the same way. Deer in the Hudson valley would be caught, tagged and injected with porcine zona pellucida, a protein made in the ovaries of pigs that protects eggs from being fertilized. The program will cost about $30,000 over the first two years, about half of which has been raised from animal rights groups already. Locals have even volunteered to help with the tracking and a catching of deer.

The locals in Westchester County seem pleased with the decision to non-violently deal with their unwanted deer neighbors. Dr. Rutburg told the New York Times: “We are bound by suburban rules in dealing with them, and violence is not how we deal with neighbors we don’t like.”

H/T Outside Magazine

More from

Deer May Be Peeing Themselves Out of Their Favorite Winter Habitats

Get the latest stories in your inbox every weekday.