Village considers allowing dart guns to control deer population

Head of the Harbor Village officials are considering allowing researchers to use dart guns to treat deer in an experimental contraception program intended to shrink the population there.

Residents have complained the roughly 600 deer living in and around the densely wooded North Shore village feast on gardens and treat expensive landscaping like “an open salad bar,” as one person wrote in response to a village survey on residents’ experiences with the animals. Residents also worried about deer colliding with vehicles on the village’s winding, unlit roads, and the animals’ role as hosts for the ticks that carry Lyme disease.

New York State’s preferred method of deer population control is hunting, which many village residents reject as inhumane. So trustees decided last year to pursue nonlethal means of population control and contacted researchers from the Humane Society of the United States and Tufts University exploring use of porcine zona pellucid, or PZP, a substance derived from pig ovaries that uses an animal’s own immune system to prevent pregnancy in wildlife populations.

Head of the Harbor would become the second community on Long Island, after Fire Island, to host the work, which researchers estimate will cost $242,215 and take place over six years. The money would come from the village, foundations and private donors.

Eric Stubbs, a member of the village’s Deer Management Advisory Committee and an economist who commutes by train to New York City, said he sees deer on his morning drive to the station about once a week. “They’re a significant presence,” he said.

Most of his neighbors are eager for the project to start, he said. “It has implications not just for us, but for towns all over Long Island . . . It’s one of the few things where you can get majority support,” he said.

Researchers use dart guns to dose female deer with PZP or sedatives so they can be injected by hand with the substance.

“What we’re hoping to do long-term is offer a solution for wildlife managers to use for areas where hunting or lethal means are not feasible or kosher with the community,” said Kali Pereira, HSUS senior wildlife manager.

HSUS dart guns — Pereira called them dart projectors — are similar to paintball guns and powered by carbon dioxide, she said. Only trained researchers use them, she said.

But the same law that effectively outlaws hunting in Head of the Harbor could keep the researchers from their work. It bans discharge of most projectile weapons including those, like the researchers use, that are gas- or air-powered.

“The activity they’re seeking to import into the village does not comply with their own local law,” said Assemb. Tom McKevitt (R-East Meadow), a lawyer who specializes in municipal law.

No-discharge laws are common across Long Island, he said. Although Head of the Harbor’s code makes exceptions for police and for non-officers who discharge a weapon “provided it is reasonably necessary for the protection of life or property,” McKevitt said it would be “a stretch” to apply that clause to the defense of perennials from hungry deer. Violators face fines of up to $250 and jail time.

In June, Mayor Doug Dahlgard asked Village Attorney Anthony Tohill to research the matter. Dahlgard said he wants any needed amendments to be in place this summer, so researchers can start their work as soon as possible. “I’d like to get it done fairly rapidly,” said Dahlgard. “There’s a lot of permitting and setup and organizing.” Tohill did not respond to requests for comment.

U.S. Department of Agriculture researchers call PZP “highly effective,” but warn that it can increase deer-vehicle collisions and other deer-human conflicts because it causes multiple reproductive cycles in female deer, which can increase deer movements. Pereira said that published data show no change in the rate of deer strikes when PZP is used.

The substance is registered with the federal government for use on wild horses and burros, but use on deer — and a host of more exotic species including sea lions and zebras — still is in the testing phase. In New York, PZP can only be used by approval of the state Department of Environmental Conservation. Researchers have not yet submitted a proposal for to use the substance in Head of the Harbor, according to the DEC.

The Fire Island study, conducted in the 1990s, found that fawning rates for treated does decreased 78.9 percent from pre-treated rates over four years.

But the deer population in that study was isolated by the Atlantic Ocean. Head of the Harbor has few natural barriers. A study in Hastings-on-Hudson, in Westchester County, might have better predictive value for the village, but it isn’t expected to finish until 2021.

DEC officials said they are skeptical that PZP can work, at least on its own. In response to written questions, DEC spokesman Benning DeLaMater wrote that PZP has not yet been proved to be a “viable, stand-alone option for managing free-ranging deer populations.”

Officials were not, at least, worried that PZP research could result in human casualties.

Darting in Hastings-on-Hudson typically takes place at a range of 10 to 15 yards. “There is little chance of any non-target being hit by a dart,” DeLaMater wrote.

And there’s no cause for worry should someone — a bow hunter, perhaps, in neighboring Nissequogue, which permits the activity — eat a PZP-treated deer.

The meat “would be harmlessly digested,” he wrote, adding that nevertheless, the agency requires researchers to mark all treated deer with tags warning against consumption.