Fencerows
By John Luthens’
“High-tech Tracking”
“Dave, you’ve got a remote-controlled buck!” Those were my first words after I saw the trail camera picture.
“Otherwise, it’s a space alien deer.” That was my next wise observation.
Maybe I’d been spending too much time watching bad science-fiction movies and not enough time in the fields and forests that encompass Wisconsin’s vast white tail habitat, where honest wildlife science is actually unfolding.
Dave didn’t actually accuse me of that, but I bet it crossed his mind.
Overactive imagination not withstanding, the facts before us were these: According to his trail-cam statistics, at exactly 3:11 a.m. on Sept. 4, 2013, in southern Outagamie County, Dave Panzenhagen, a deer hunter from Greenville, captured a picture of a fork-horn buck wearing a radio collar.
Pictured: Trail camera photo of a collared buck.
And by the way, according to the camera, the exact temperature at the time was 45 degrees Fahrenheit, which probably isn’t all that relevant, say, like playing Angry Birds on your smart phone – but I guess since the technology is there, you might as well use it.
Dave and I took turns hypothesizing what it meant, where the deer came from, and what exactly it was doing in his willow swamp. After we had exhausted the possibilities (including all of my far-fetched ones), we decided to do some real fact-finding. Hunting season was upon us. We set out to track the buck down.
We started on the DNR website: http://dnr.wi.gov/topic/wildlifehabitat/research/whiteTailedDeer.html
We assumed (correctly, as it turned out) that it would be far easier to go high-tech tracking than to actually trek into Dave’s hunting property. Neither of us was in top hunting form yet. We weren’t certain how much weight a radio collar might add to a drag out of the willows or how tangled up it might get.
As an afterthought, we weren’t entirely certain it would be legal.
Browsing the DNR web pages, we came across several studies currently being conducted on Wisconsin’s white-tail population; Studies ranging from deer-vehicle collisions to the impact of predators and winter weather on fawn survival. But the one that caught our eye, like a broken branch or a trace of blood on a leaf, was the Buck Mortality Study. The wind was turning in our favor as we moved through the forest of the internet.
According to the DNR, the Buck Mortality Study hinges around the concept of the buck recovery rate (BRR), which is the portion of bucks killed by legal hunters every year. Used as a population gauge, the BRR assumes that the relative age of bucks registered in a management unit is representative of the age structure of the entire population in that unit.
Given quality deer management practices and hunter selection for more mature bucks, along with increased vulnerability of yearling bucks to harvest, BRR statistics are open to some degree of error.
The trail of our buck warmed when we learned that the study involved maintaining 30 radio-collared bucks in two areas of Wisconsin, with expectations of giving DNR researchers a more accurate understanding of BRR in a variety of deer habitats.
One area stretches through the forested northwest reaches of Sawyer County, and the other fence-hops the farmlands and woods of east central Wisconsin. The two studies are diverse in habitat, types of predators, as well as hunting pressure and vehicle traffic.
An integral part of the study objective is to measure deer mortality caused by hunting, and a marked or collared deer is legal to harvest. One of our lingering questions was answered.
And unless our collared buck was adapted to freeway driving, we figured it didn’t come from the Sawyer County study area. Outagamie County, however, was right in the east-central wheelhouse. We were closing in, but we needed a guide to help us over the final terrain.
One name in particular came up in connection with Wisconsin’s white-tail studies, Dan Storm, who recently joined the DNR as a deer and elk research ecologist. I contacted him not knowing what to expect, if anything, but it turned out his research technicians were able to pin down the specifics of our animal quicker than it takes me to run to my stand on opening morning.
Dan related that bucks captured during the winter months are fitted with elastic collars and monitored for location at least once a week. The collars send out a mortality signal if no movement is detected for a period of time, in which case the technicians go into the field to investigate, or possibly wait for a harvested collared deer to come into a registration station.
Given the general location of the trail camera and the nearest road intersection, the monitoring equipment triangulated the signal of our animal. Going back to their research notes, Dan’s crew was able to pinpoint where and when it was captured, and how far the buck had traveled since it was collared and released.
“This buck was captured on Jan. 26, 2013,” Dan related to me. “The really interesting part is that this buck traveled 15 miles southeast, from it’s time of capture to when crossed your camera this fall.”
Looking at a map, I asked Dan if the approximate location of capture was the Navarino State Wildlife Area. He told me that was likely quite accurate, but it may have been captured on private land.
“Without the help and cooperation of the landowners, volunteers, and hunters in the state, allowing access to the land, helping with the capturing, and reporting what they see, these studies wouldn’t be possible,” he said.
Dan seemed especially interested in how far our buck had come since capture, as another benefit of the tracking study is to monitor the condition of the animals when they are collared and correlate that with data on how far they travel.
“The specific notes on your buck say that it was a large bodied button buck, and was captured solitary,” he said, adding “We are in the process of putting together data to see if the smaller animals move the furthest because they are forced out by dominant bucks, or if the bigger animals move further because they are physically more capable.”
According to Dan Storm, final capturing and collaring efforts in the Buck Mortality Study will occur in 2014, with monitoring to continue as long as remaining collars give off signals.
Dave and I shook hands at the end of the hunt. It was a fascinating stalk into the world of high-tech tracking. Now, with the mystery of the collared deer solved and safely in the files, only one question remains: Come opening morning, why don’t they put collars on all the big bucks and give me some of that fancy tracking equipment?