Fawn research continues to address survival concerns, with help of volunteers
Published: May 7, 2013 by the Central Office
MADISON - This past winter, hundreds of volunteers helped state wildlife researchers in capturing and placing radio collars on yearling and adult deer. Now researchers would like help locating and radio collaring newborn fawns during May and June.
"Most fawns are born during the last week of May and first week of June, which is a short time frame to meet our goal of getting radio collars on 80 fawns," said Jared Duquette, Department of Natural Resources ungulate research ecologist.
"Mother deer do not make our job easy," explains Duquette. "They typically hide their fawns in thick vegetation or in expansive grassy fields where the fawns are naturally camouflaged and remain motionless. We have to do a lot of walking to find them and rely on strength in numbers with our volunteers. It's a lot of fun to find these little guys, and helps us get key information on fawn survival."
Volunteers will be assigned to search teams working in the vicinity of Shiocton in Shawano County and Winter in Sawyer County. Each day, teams will comb targeted fawning areas - on foot - for a few hours to find the hidden newborns. Once found, fawns are fitted with expandable radio collars to monitor their movements and survival during their first year of life to assess causes of death, which can include malnutrition, environmental influences, vehicles, hunters or predators. If a fawn dies, the collar will emit a unique signal that researchers use to locate the animal to evaluate cause of death. The collars are designed to expand as the deer grows and eventually drop off as the animal reaches its first birthday.
Duquette said during 2011 and 2012 "thanks to the help of volunteers across the state, researchers had wonderful success capturing fawns." A total of 212 fawns, including 144 (94 radio collared, 50 ear-tagged) in the Shiocton area and 68 (60 radio collared, eight ear-tagged) in the Winter area, were captured.
Even those who don't join the fawn search can get involved in the predation and fawn recruitment study. "Fawns are often harder to find in the northern study area, due to lower deer density and greater expanses of woods. We'd appreciate if citizens could notify us if they see a fawn in the study area so we can meet our research goal," said Duquette. Anyone observing a fawn within a 10 mile radius of the town of Winter during May and June should contact researchers at (608) 219-0771.
For more information and to sign up as a volunteer search Deer Research on the DNR website.
Impact of predators on deer populations of special interest to hunters
Some hunters have questioned the fawn recruitment rates that wildlife biologists use to estimate deer populations. Recruitment is the proportion of fawns that survive to reproduce and it is a primary influence in deer population growth. At the end of this three year effort to monitor fawns, researchers hope to fine tune their population estimates based on the real-world data collected.
"Estimating fawn survival rate is vital to the accuracy of our deer population estimates," said Duquette. "This study can also tell us about the impact predators are having, whether it's black bears, bobcats, coyotes, or gray wolves."
Preliminary results from the study in 2011 and 2012 showed that most fawn mortalities had occurred by the end of August, mostly from predation. Fawn survival (up to 9-10 months old) was 62percent in the Shiocton area compared to 35 percent in the Winter area, though fawns in both areas had better survival in 2012 than in 2011. Fawn predation rates have been less in the east-central (41 percent) than in the northern (62 percent) study area, which Duquette said may be due to the greater diversity of predators found in the north. Other sources of mortality included vehicle collisions, starvation, and hunters.
"Predators have had the biggest impact on survival so far, but we know predation rates can change with underlying environmental influences, like a harsh winter, that make it harder for fawns to survive. So we're trying to look at how all these factors interact," says Duquette.
This research is possible only with the collaborative efforts of hundreds of Wisconsin citizens and groups such as the Wisconsin Conservation Congress, Safari Club International and Whitetails Unlimited, the University of Wisconsin- Madison and UW-Stevens Point, the AFL-CIO Union Sportsmans Alliance.
FOR MORE INFORMATION CONTACT: Jared Duquette - (608) 225-2951 or Bob Manwell - (608) 264-9248