Oh, dear, oh deer

UND wildlife researcher’s surgical sterilization collaboration with Cornell University has caught the attention of urban planning boards across the country

Jay Boulanger

UND Assistant Professor of Wildlife Ecology Jason Boulanger has done extensive research and field work revolving around deer overpopulation and management. Image courtesy of Juan Pedraza of UND Discovery magazine.

On Dec. 9, 2013, the cover of TIME magazine didn’t feature the portrait of a powerful world leader or an illustration of the latest social upheaval. The central image was instead a tranquil woodland scene with a young deer front and center.

The cover story that day: America’s Pest Problem.

“Deer are a keystone species, which means that they can significantly affect not only their own habitat, but they can affect the habitat of others,” UND Assistant Professor of Wildlife Ecology Jason Boulanger explained, pointing to a number of impacts to ecosystems, other wildlife species and humans themselves.

Boulanger has done extensive research and field work revolving around deer overpopulation and management. One of his largest professional endeavors—a six-year collaboration with Cornell University—has been getting some national attention after the study was published a few weeks ago, due to its unanticipated outcome.

As the Deer Research and Management Program Coordinator in 2007, Boulanger and his team were charged with finding a way to trim down deer numbers on and around the Cornell campus. The campus was like a lot of other suburban landscapes suffering from the impacts of deer overpopulation, such as increased deer-vehicle collisions and damage to agriculture and local ornamental plantings.

The trick to this undertaking was that the Cornell community wanted to get rid of the deer problem without using lethal control methods.

“Cornell is a very liberal campus, so we just didn’t feel the political climate at the time would be right to be able to do a controlled hunting program. There had been some research in previous years suggesting that surgical fertility control could be a way to reduce deer populations over time,” Boulanger said.

The large animal hospital at Cornell’s College of Veterinary Medicine offered Boulanger and his team an opportunity to combine efforts. If the deer management crew could bring them deer, the school could train their vet resident surgeons how to sterilize the deer. They had a subsidized price to do so, but it was still very expensive–at about $1,200 a deer.

Problem unsolved

Ultimately, 93 does were captured, surgically sterilized, and rereleased back into the community with radio collars and ear tags. What researchers found after six years of tracking the deer was not what they expected.

“We didn’t reduce the deer population at all based on our population estimates. We were scratching our heads wondering what happened,” Boulanger grinned. “It was a very expensive program to not be effective.”

Boulanger explained that his team did see a big decline in fawns on campus—new deer were certainly not being born. However, the number of bucks on campus increased by an incredible 873 percent. They hypothesized that once the bucks had bred all of the does around the outer edge of campus, the type of surgery used—tubal ligation—allowed many of the does to continue cycling through March.

“If you’re a buck on the outskirts of town, and you smell 50-or-so deer in heat on campus, what are you going to do? It might attract some attention and draw some bucks into the area,” Boulanger said.

Cornell officials understood the findings and allowed a controlled hunt on campus, which reduced the deer population by almost 50 percent. The meat that was collected from the hunt was distributed to families and local food pantries.

Bringing research west

Controlled suburban hunts like those used by Cornell are already happening in the North Dakota communities of Bismarck and Fargo. Boulanger said that although the state has been characterized as having fewer deer on the landscape the past few years, there are still issues in cities.

“Suburban areas are the perfect habitat for deer. They don’t have hunters or predators to worry about and they have a subsidized food source, because people have ornamental plantings they can feed on in the winter months,” he said. Also, some people in North Dakota may intentionally feed deer.

The Greater Grand Forks community has recently raised concern over deer damage in the southern parts of town, where trees support cover during the harsh winter. Boulanger said if population management becomes essential, he wouldn’t recommend surgical sterilization based on his research.

“Controlled hunting or sharp shooting programs are the way to go. Currently, we know that it’s the least expensive option, and it’s the most effective of the options we have.”