This research project in northeast Wyoming began in December 2019 when 35 mule deer does in Hunt Area 10 of the Cheyenne River Mule Deer Herd were captured and fitted with GPS collars. The primary objectives of the study are to identify habitat preferences, daily and seasonal movement patterns and causes of mortality.

This hunt area was targeted for research due to its importance in providing public land access for hunting and for recent poor fawn production and overall depressed deer numbers. The 2019 fawn-to-doe ratio in Area 10 was 53 fawns per 100 does. A higher ratio is needed to maintain or build deer numbers.

The collars are tracking each deer’s movements for the next five to six years, depending on the collar’s battery life. The collars transmit deer locations every eight hours. The collars are also recording finer-scale, three-hour movements, which are stored onboard the collar and will be downloaded when the collar is retrieved from a deceased animal or at the end of the study when it is programmed to automatically release.

Eight mortalities of collared deer have occurred with causes identified as predation, vehicle collisions and several unknown. Two animals were tested for chronic wasting disease and one tested positive, though it is unclear if the disease was the primary cause of death. The collars from these mortalities have been retrieved and deployed on other deer.

"We have not seen any significant seasonal dispersal of deer away from their original capture areas," said Gillette Wildlife Biologist Erika Peckham. "Additional data will come later in the study, but so far, the collared deer are showing limited movements, which suggests we might focus attention on habitat in those areas in the future, both measuring current conditions and quality and what potential improvements could be initiated." 

Funding for the collars has been generously provided by Thunder Basin Coal Company, through collaboration with the U.S. Forest Service and by the Wyoming Sportsman’s Group.