Tracking movement of Princeton’s deer no small task

Rutgers student taking part in pioneering contraceptive field research.

By: David Campbell
   While the controversy surrounding Princeton Township’s deer cull has quieted down for now, ongoing research is well under way in the township’s southeast woods.
   Two or three times every week, B.J. Hubert, an animal-science major with Cook College at Rutgers University, drives out to Princeton to look for deer.
   According to Dr. Larry Katz of Rutgers’ Department of Animal Sciences, "We’re trying to get a picture of how large the area these animals inhabit is.
   "If you’re going to control populations, you need to have a sense of what is a population," Dr. Katz continued. "For this locale, we’re trying to get a sense of what their movement patterns are."
   Mr. Hubert is gathering data for the township’s pilot birth-control study. In late February and March, 20 does were tagged, fitted with radio-tracking collars and immunized with the one-shot vaccine SpayVac, which has proven in trials on captive white-tail deer at Penn State University to last up to three years.
   Princeton’s study will test the efficacy of the vaccine in the wild. If it works, it could provide a means to control the municipality’s deer population with less reliance on other, more controversial methods like sharpshooting and captive bolting.
   According to Tony DeNicola of White Buffalo, the Connecticut wildlife-management firm Mr. Hubert works for at a research stipend of about $1,200 a month, the animal-science student is monitoring home-range patterns and reproductive status.
   Mr. Hubert is tracking the animals’ grazing patterns to determine how far afield they roam. A couple of times every week, he goes out with telemetry equipment and a log book to find the tagged animals and plot their locations.
   The data will be entered into a computer to create a picture of the animals’ movements and distribution, and systematically project what parts of the neighborhood each deer is occupying, Mr. DeNicola said.
   If they don’t roam far, it will confirm Mr. DeNicola’s hypothesis that a population in a targeted area can be managed through an immunocontraceptive program. If the deer prove to wander too far, Mr. DeNicola said, it could undermine the program.
   Two of the 20 vaccinated deer recently died, one being struck earlier this month by a motor vehicle in Princeton Borough around Harrison Street and Prospect Avenue.
   While the animal technically was outside the study area boundary when she was struck, she died within a quarter mile of where she was tagged, which is in keeping with projections, Mr. DeNicola said.
   "She didn’t wander far," he said.
   The second deer was found dead from unknown causes April 30 on Philip Drive, possibly because of accidental poisoning.
   Contrary to speculation over the deaths’ impacts on the program, Mr. DeNicola continued, the two deer in fact provide valuable population data.
   "We want to know trends in mortality," he said. "It’s actually a gain in terms of data collection and insight. Tagged animals die — that’s OK. These are the data we want."
   In the next couple of weeks, Mr. DeNicola will be coming back to the township to conduct nighttime spotlight surveys of the study-area population with Mr. Hubert to get a more accurate count of the population there. Mr. DeNicola said the population may be larger than the 50 or so earlier estimated, closer to around to 80 to 100 deer.
   That along with setbacks caused by illegal feeding by a neighbor, he continued, means that between 40 to 60 deer will need to be vaccinated next year.
   "By March, nearly every female in the study area, about 80 percent, will be radio collared," Mr. DeNicola said. "The more animals marked, the more accurate our projections will be."
   When Mr. Hubert is in the field, he’s also gathering reproductive data. According to Mr. DeNicola, the study team doesn’t expect to see results from the SpayVac vaccinations until 2006. That’s because the does vaccinated this year were already pregnant, as will be the case with deer treated next year.
   Offspring will have to be treated, and only then will measurable results be possible. But Mr. DeNicola said next year blood tests should show whether the vaccine has prevented pregnancy in the first round of treatments.
   In the field, Mr. Hubert observes which fawns are lactating, and which does have successfully reproduced.
   "It’s likely that in the next few weeks, we’ll begin to see fawns grazing next to the mothers," said Dr. Katz.
   But the Rutgers student’s biggest contribution in terms of time will be his help in capture and vaccination of deer next winter, said Mr. DeNicola.
   As part of Mr. Hubert’s education, Mr. DeNicola continued, he wants to give the student full exposure to field work of this kind, even when it comes to dealing with the media and the public, which he said has been a large part of the job in Princeton.
   "That’s part of it," Mr. DeNicola said. "I want to give him a full world experience, not just of academia."
   Mr. Hubert already seems to be learning. He declined to return calls for this story.