Mild winter conditions and lack of snow made for challenging survey conditions this spring for wildlife staff in southwestern Montana. But the warm winter weather likely helped mule deer winter survival and fawn recruitment in many areas.
These were key takeaways from post-hunting season and spring mule deer surveys conducted by wildlife staff with Montana Fish, Wildlife & Parks. The annual surveys provide trend data on overall mule deer population estimates, herd makeup and fawn recruitment, and they inform management decisions in accordance with Montana's Adaptive Harvest Management Plan for mule deer.
Biologists conduct mule deer surveys in trend areas that allow for repeatable surveys of a sample of herds within a larger surrounding area. Results are comparable from year to year and form a long-term average, which is based on all years for which data is available. These aerial surveys happen away from roads, in the early morning or late evening hours when deer are most active, and in areas where deer usually concentrate seasonally—factors that allow biologists to count and classify deer most efficiently.
This past winter was exceptionally mild with very little snow at middle and lower elevations. In southwestern Montana, that led to an early and widespread spring green-up and mule deer herds that were widely dispersed at times when they're usually congregated in smaller areas. This made spring trend surveys challenging for FWP staff. However, biologists gathered valuable fawn recruitment data, which is less dependent on ideal survey conditions.
Sheridan area
Surveys in the Sheridan area, which include the Snowcrest, Sweetwater Hills, Tobacco Root, Ruby, Red Rock, and West Greenhorn mountains, observed above-average fawn recruitment everywhere deer were classified. Recruitment ranged from 17 to 60 percent above the long-term average. Both fawns and adult mule deer appeared to be in good body condition, and high recruitment is expected following two consecutive mild winters and good forage.
Dillon area
Surveys in the Dillon area include the Lima Peaks, East Pioneer and Tendoy mountains. Recruitment here remains strong, with more than 50 fawns per 100 adult deer observed. Minimum counts—the actual number of deer observed—were 25 percent greater than the long-term average in the Lima Peaks and similar to the long-term average in the East Pioneers.
Bozeman area
Mule deer numbers in the Bridger Range remain within the 20-year average but below the long-term average. Fawn recruitment here is robust with 53 fawns per 100 adults, about 66 percent above the long-term average. Minimum counts were within the long-term average in the Madison Range, where mule deer numbers have been stable over the past 30 years.
Livingston area
A survey in the Brackett Creek trend area found a total count that was 3 percent less than the 10-year average but 40 percent lower than the long-term average since 1979. Fawn recruitment was also lower this year, down 33 percent from 2025 and 3 percent lower than the long-term average.
Butte area
A trend area near Fleecer Wildlife Management Area continued to show stable fawn recruitment at 36 fawns per 100 does, just above the long-term average. The total count was 510, the highest since 2018 but still below the long-term average of 591. Buck harvest in HD 319 remains low.
Mule deer populations in the south Boulder area have been on a declining trend since 2019. This year, biologists counted 34 fawns per 100 does, compared with a long-term average of 41 fawns per 100 does.