Deer research project is in final year of field work
DODGEVILLE – A woolen cloud deck hung low over the coulees of Iowa County, snuffing out any chance of seeing the morning sun on this late January day.
A recent snowfall, too, added to the thick blanket of white on the landscape.
Under the dim cloak of winter, it was even a challenge to detect the horizon over a nearby farm field. Where did the Earth end and the sky begin?
How many other secrets were hidden in the these scenic ridges and draws?
Two crews of Department of Natural Resources wildlife technicians were hard at work to answer questions related to Wisconsin's most important game species, the white-tailed deer.
Fifteen netted structures called clover traps had been set on a rolling, wooded private property west of Dodgeville.
The goal was to capture deer, take biological samples, attach GPS collars, release the animals and follow their movements for the rest of their lives. Hopefully, too, determine what caused their deaths.
The work is part of a landmark fiveyear project called the Southwest Wis
consin CWD, Deer and Predator Study.
"We've got a buck!" said Wes Ellarson as he jumped off an ATV and sprinted over to a trap in a secluded hollow.
A nine-point whitetail writhed under the black netting and metal frame. Ellarson's colleagues Matt Hunsaker and Dana Jarosinski were already at the scene.
Although the technicians have many years of experience at trapping and handling deer, capturing a mature buck is rare.
An added charge of excitement was evident as the crew began a well-orchestrated and practiced sequence of actions to subdue the big whitetail: Ellarson and Hunsaker applied their muscle and weight on top of the deer while Jarosinski injected a sedative into its left hindquarter.
Jarosinski also slipped a neck gaiter over the animal's eyes.
The buck bleated several times but soon stopped struggling. After 10 minutes, the drug had taken full effect; the technicians dragged the deer out of the trap to begin the next phase of their work.
They grabbed backpacks and tackle boxes and spread gear on the snow. Instantly the remote site was converted to a field laboratory.
Over the next 10 minutes, blood, rectal, nasal mucous and ear tissue samples were taken, a GPS collar was attached and activated, the animal's temperature and respiration were recorded, its general condition was assessed and it was weighed.
Elsewhere on the property another DNR crew – wildlife technicians Tanner Klein, Nadine Pershyn and Robin Schmitt – were also checking traps and working up deer.
The DNR calls the project the largest and most comprehensive deer research project undertaken in Wisconsin.
Its goal is to examine factors that could impact deer survival and deer population growth in southern Wisconsin, including chronic wasting disease, predation, habitat suitability and hunter harvest.
As such, it's the first research in a whitetail-rich habitat to examine the effects
of CWD on the deer herd.
Studies in western states have estimated CWD-linked declines in some deer and elk herds. But no such work has been conducted in an area of whitetail abundance in the East or Midwest.
Similar to studies conducted in northern and eastern Wisconsin from 2011-14, deer in the southwest are being tracked and evaluated for causes of mortality.
Unlike the earlier projects, the new initiative is testing deer for CWD, collaring and tracking predators, estimating predator density, assessing habitat more extensively and coordinating animal movements with the Snapshot Wisconsin trail camera project.
In addition, the genetic profiles of the deer will be analyzed and cataloged. Further, tissue samples will be provided to Joel Pedersen at UW-Madison to assist with research on new CWD testing procedures.
The five-year budget for the project is $5.07 million, according to Dan Storm, DNR deer research scientist.
Most of the funding started with a special allocation in 2016 from formerGov. Scott Walker's CWD initiative; all of
the money is derived from the federal Pittman-Robertson Fund, an excise tax on firearms, ammunition and certain hunting products.
The five-year study started late in 2016 when some predators were collared. But it kicked into high gear in January 2017 with the trapping and collaring of juvenile and adult deer. In May 2017 newly born fawns also were collared.The activity has continued seasonally.
This year marks the final year of capturing and collaring deer in the study. To date, 319 fawns, 796 deer ages 6 months through adult, 41 bobcats and 69 coyotes have been collared.
The work is being conducted almost entirely on private land; 351 landowners have allowed DNR crews and volunteers access to their properties.
Among preliminary results, CWDpositive deer in the study have died at significantly higher rates (three times greater in 2017 and two times greater in 2018) than animals without the disease.
However, the cause of death of CWDpositive deer in the study is not always CWD. Compromised by the disease, the animals also are killed at higher rates by cars, hunters and predators than CWDnegative deer.
Storm said the agency did not plan to release additional preliminary information from the study.
A "full court press" will be put on analyzing all the data in 2021, he said.
Arguably the $64 million question in the project is: Is CWD causing a population-level decline in the deer herd in the Wisconsin study area?
That answer will come later.
For now, the field crews continue to collar as many animals as possible. Volunteers will also be sought to assist with fawn searches in May and June.
The late January day turned out to be a milestone for the two DNR crews west of Dodgeville: Nine deer were captured and collared on the property, a singleday clover trap record for the project.
The crews also use large drop nets, which have accounted for about 75% of deer captured in the study, Ellarson said.
On this day, the 9-pointer was the only adult buck captured. It was notable for more than its age and sex.
It had been trapped and collared twice before.
At about 8 months of age on Feb. 26, 2017, the deer weighed 79 pounds. The next year on March 7, 2018, the buck weighed 139 pounds.
And on Jan. 28, 2020, as a 31⁄2-year-old, the animal was 188 pounds.
Its CWD status in 2018 was negative; it remains to be seen what this year's testing shows.
After a 20-minute workup, the buck was injected with a reversal drug. Minutes later it raised its heavy-antlered head, stood up and wandered up the adjacent knoll and out of sight.
Will the buck get taken by a hunter this fall? Will it succumb to CWD? Will it get hit by a vehicle?
Whatever befalls the deer, like all the animals in the study, it has a certain immortality.
Even after it dies, data from its tissues and movements and life history are likely to help inform wildlife management for many years to come.
The project is seeking volunteers to assist with fawn capture in May and June. To learn more or sign-up, visit dnr.wi.gov or call the deer research team at (608) 935-1940.