JACKSON, Wyo. — In December, Wyoming Game and Fish Department (WGFD) wildlife managers in the Jackson and Pinedale regions took to the sky to conduct annual aerial surveys to assess mule deer populations.
During these surveys, biologists and game wardens flew over winter ranges from a helicopter to tally the number of observed fawns, does, yearling bucks and adult bucks. According to the WGFD, managers have continued to evaluate mule deer recovery in the Wyoming Range and Sublette herds following the severe winter of 2022/2023, which resulted in above-average mortality.
The agency’s long-term research, conducted in partnership with the University of Wyoming, indicated that mule deer entered the 2024/2025 winter in “good body condition.”
The December aerial classification survey count for the Wyoming Range herd was 4,902, in hunt areas 134, 135 and 143-145. This indicated a considerable increase in fawn ratios at 83 fawns for every 100 does, up from 34 fawns for every 100 does surveyed in 2023, per the report.
Additionally, the surveys recorded that the overall buck ratio was up with 28 bucks for every 100 does. While the ratio of adult bucks remained stable, the increase in yearling bucks contributed to a rise in overall buck ratios for the herd.
Last summer, WGFD south Jackson Wildlife Biologist Gary Fralick captured fawns on the ground in the Wyoming Range. The average birth mass of newborn fawns was 7.7 pounds, the largest measurement recorded since 2016, and nearly 1 pound larger than average birth mass across all previous years, per the WGFD study.
In the Sublette herd, which includes winter ranges in hunt areas 130, 131, 138, 139, 140 and 142, biologists recorded 7,645 mule deer during the December flight survey. The classification survey indicated a fawn ratio of 76 fawns for every 100 does — the highest ratio observed since 2006, according to the report. The overall buck-to-doe ratio remained stable at 34 bucks for every 100 does, identical to the findings from 2023.
Fralick wrote in the study that both herds have demonstrated resilience after recovering from periods of high winter mortality.
“We witnessed this recovery in the mid-2000s and again from 2011/2016 and 2017/2022,” Fralick said. “During those times, the mild and open winter conditions led to high over-winter survival rates for mule deer and rapid recovery of the populations.”
As the Wyoming Range and Sublette herds continue to recover, wildlife managers will continue to assess mule deer hunting season recommendations, according to the WGFD.
