One of Wisconsin’s great treasures is its abundance and diversity of wildlife. From bears and beavers to ducks and deer, the Dairy State has it all.
Managing such a diverse population requires an understanding of the animals and their habitat and that can only be achieved with thorough research.
That’s where the Wisconsin Department of Natural Resource’s (DNR) Office of Applied Science comes in. They are the research arm of the DNR’s Division of Fish, Wildlife, and Parks and according to Dave McFarland, the office’s wildlife research team leader, their work sets a platform for management policy.
“What we do is provide that base scientific information,” said McFarland, who recently spoke as part of the University of Wisconsin’s Science on Tap speakers series held in Minocqua. “We try to provide the best information we can on what’s happening on the ground. What’s happening with these wildlife populations. What’s happening with the habitats that they use. So that at least that part is as solid as possible and can inform these very complicated decisions.”
Monitoring Wisconsin wildlife, however, is a monumental task, but McFarland offered a glimpse into a number of his team’s studies that are using some ingenious methods to gather information on a number of species.
Until recently, to establish population estimates, beaver colonies were monitored with the help of helicopters flying low over set survey blocks of beaver habitat.
“It’s the most fun I’ve ever had at work,” McFarland admitted.
It was expensive, however, to put a helicopter in the air for beaver counting, around a $1,000 a day, so the research team came up with a much less expensive method: get the information from those already in the field — the trappers.
The DNR began giving diaries to beaver trappers to document where they trapped, the days they trapped, the number of traps set, and the number of beavers captured.
The cost was a couple thousand dollars a year rather than a half a million.
“It’s providing information that we need to make management decisions, and it’s doing it much more efficiently, and so we’re going to continue with that,” McFarland said.
In a different beaver study, the DNR is flipping its methods with regard to studying beaver dams on trout streams.
Based on past research, policy recommended the removal of beaver dams on certain trout streams, as they were thought to be detrimental to the trout.
To take a fresh look at that policy, on a handful of streams where beaver dams had been previously removed, the DNR is now letting them be. But on some streams where beaver dams were previously allowed to stay, they are being removed.
Beaver-trout interaction will be then be monitored to determine how the trout respond to each scenario.
McFarland said the study will perform a check on the current policy of beaver dam removal.
“To see if we can better inform this pretty significant management action that’s being taken on beaver,” he said.
Ring neck ducks
A recent study in Minnesota showed ring neck ducks there were having low nest success and researchers were wondering if that situation was the same across the region.
In response, McFarland said the Wisconsin DNR then started monitoring Wisconsin’s ring neck duck population.
“They’re notoriously difficult birds to study because they are at low densities and they nest right on the edge of these floating bog mats that are all over the place. So they’re really hard to get to,” he said.
To remedy the situation, McFarland said drones with thermal detecting cameras, set to the temperature of a duck, began being used to survey ring neck duck habitat.
“It really improves our efficiency and it’s been a really neat project,” he said.
Through the use of drones the Wisconsin DNR researchers have been able to collect data on nest success, survivorship, and brood sizes of ring neck ducks and compare them to the Minnesota data.
DNR researchers aren’t the only ones getting in on the fun of monitoring Wisconsin’s wildlife. Citizens are in on it, too.
Snapshot Wisconsin is a citizen based project in which 1,700 volunteers operate a network of 2,000 trail cameras, issued by the DNR, covering one-third of Wisconsin.
To date over 35 million pictures have been produced of wildlife that has walked in front of the cameras.
And while entertaining to the thousands who capture and view them, the pictures are also of great scientific value.
“We’re using this information. We’re collecting information with trail cameras in a systematic way to generate data to help us monitor wildlife,” McFarland said.
Snapshot Wisconsin is the largest DNR citizen science project going on in the state right now and it has helped with everything from fawn to doe ratios to turkey brood estimates to bear litter size counts.
He said the data is also proving to be very valuable with monitoring the newly introduced elk herds in the Clam Lake area and Black River State Forest area.
“We’re taking advantage of the Snapshot Wisconsin data,’’ McFarland said. “Taking advantage of the fact that we know almost exactly how many elk there are to develop these new models that will allow us to estimate populations from camera data.”
Research concerning Wisconsin deer is currently focused on Chronic Wasting Disease (CWD), the neurological disease that has reeked havoc on the state’s deer herd.
This year was the fourth year the DNR has been capturing deer, testing them for CWD, and then radio collaring them to track them.
“We’re looking at how those two groups, the (CWD) positive and the (CWD) negative, what their fates are,” McFarland said.
The data collected has shed light on survival rates of deer, the effects of CWD on deer, and the ways the disease is transmitted and spread.
So far 548 adult deer and 323 fawns have been radio collared and tracked in southern Wisconsin in the Dodgeville area, which is in the heart of the state’s CWD infestation; 351 property owners have participated in this study, which is the largest wildlife research project the state has ever undertaken.
Deer predators, including 32 bobcats and 69 coyotes were also collared.
Bobcats have also been monitored right here in the Northwoods.
“We have bobcat research happening right here,” McFarland said. “It’s centered right in the Rhinelander-Minocqua area.”
Over the last couple of years, 75 bobcats have been collared.
That is an enormous sample size for a species very difficult to capture, according to McFarland, and it was achieved with the help of trappers.
The DNR sent out a letter to trappers requesting they call the DNR if they trap a cat that they choose not to keep.
“It’s a great way to involve trappers. It’s a great way to involve citizens in our work, and it’s also really efficient for us,” McFarland said.
The study was designed to look at the survivorship of bobcats and it eventually led to a higher harvest quota.
In response to demand, the harvest quota for bobcats was doubled and the data collected from the radio collars suggested that the survivorship was unaffected.
“By increasing the quota we didn’t have any impact on survivorship at all,” McFarland said. “That told us that that was a sustainable harvest level. We were able to maintain it.”
The DNR not only uses technology like cameras and radios in their research, they also now use genetics.
“It’s become a tool that’s affordable to use at a statewide scale,” McFarland said.
This year for bear population estimates, the DNR set up 844 hair snares in 32 counties across bear country. These were barbed wire corrals surrounding a pit containing buried peanut butter and cooking oil as a scent attractant.
Curious bears would leave hair samples on the barbed wire and those samples could then be genetically attributed to an individual bear, which could therefore be tracked.
Seven thousand hair samples were collected.
Through the study DNR researchers were not only able to gauge an area’s population, but also learn how often individual bears returned to the same site or visited a different one.
“From that we can calculate the number of activity centers and the density of bears around each of these clusters of sites and we can extrapolate that to a statewide population estimate,” McFarland said.
He also noted Wisconsin has the highest black bear harvest of anywhere in the country, as well as a population that can support it.
“Wisconsin has one of the highest density black bear populations on the continent,” McFarland said. “We’ve got a ton of bears.”
Jacob Friede may be reached at [email protected] or [email protected]