FWP Region 6 Mule Deer & Whitetail Deer Aerial Survey findings released

Montana Fish, Wildlife and Parks Region 6 biologists have completed their 2018 winter and spring aerial surveys of deer populations across northeastern Montana, which are used to help determine management recommendations. The surveys indicate above average numbers for mule deer, and mostly stable populations of whitetail deer across the region.

“Data collected during deer surveys are only one factor in deer management recommendations,” FWP Outlook-area biologist Ryan Williamson (and Region 6 deer specialist) explained. “The prior year’s harvest, weather, and habitat factors, as well as additional input gathered from landowners, hunters, the public and other agencies are all considered by the Fish and Wildlife Commission for season and quota setting decisions.”

Mule deer

For mule deer, 11 trend areas in Region 6 are typically examined each year from the air. The winter “post-season survey” was completed in January, and the “spring survey” was conducted in late April and May. While total deer counts tend to be variable, the 2018 surveys indicate mule deer are doing quite well. “Mule deer trends remain stable and well above average across most of the region,” Williamson said.

The 2018 post-hunting-season surveys showed the region-wide mule deer population at 74 percent above average, but 15 percent below the 2017 survey.

The 2018 spring surveys showed region-wide populations at 46 percent above average and remain the same as the last year’s spring survey. While regional numbers indicate above average mule deer levels overall, differences are seen across the region and in isolated areas as well. According to Williamson, mule deer from the 11 deer trend areas range from slightly below average to well above the average.

This same trend was seen in the deer fawn-to-adult ratios that are also calculated from the spring survey. Region wide, the fawn numbers continue to do quite well and remain above average.

“Fawn to adult ratio is an indicator of over-winter survival as well as new recruitment into the population,” Williamson said. “The 2018 survey showed 57 fawns to 100 adults across the region, which is slightly above the average of 53 fawns to 100 adults. These numbers were also similar to the 2017 survey.”

Winter mortality was variable across the region during the 2017-2018 winter with the highest impacts seen in localized areas around Malta and Havre. “Winter mortality was observed in western areas,” Williamson noted, “with mostly fawns succumbing to the winter weather.”

Although a long, tough winter was observed throughout the region, the eastern portion did not experience near the snow accumulation as seen throughout the western portion of the region in areas where near record snow depths and extreme cold temperatures were observed.

“The region experienced a wide range of abnormal weather in the last year. Much of the region experienced a significant drought in 2017, particularly the eastern portion, which had significant impact on habitat conditions,” says Williamson. “Fawns likely went into the harsh, long winter in poorer condition than normal which likely impacted overall winter survival.”

The mule deer appeared to have overwintered well. FWP Malta-area biologist Brett Dorak in Malta adds, “We understand there will be a variation in survival across the region, but overall things are looking great coming out of a bad winter.”

Another pressing factor in managing deer populations is the threat of chronic wasting disease (CWD) that was discovered last year in wild herds in Montana, both in Region 5 and Region 4. CWD has not yet been found in Region 6, but has been detected just across the Montana border in Alberta and Saskatchewan.

“It is just a matter of when and where CWD will be detected in Region 6,” says Williamson. “Higher deer densities tend to influence the spread of the disease, so we take that into consideration when developing hunting season regulations and the number of antlerless deer B-licenses available.”

For 2018, most of the hunting districts will be managed under the liberal regulations for mule deer, which includes either-sex for a general deer license (A-tag), as well as additional antlerless B-licenses. “The liberal regulation package is expected in hunting districts, specifically along the Canadian border. As normal, hunting district 652 continues to be a limited permit district and will have a limited number of B-licenses available,” Williamson said. “All hunting districts will have a varying number of mule deer B-licenses available this year, with the license application deadline on June 1.”

Whitetail deer

Whitetail deer populations continue to recover across the region as well. Due to more uniform habitat, the whitetail surveys tend to look at deer density, as opposed to total numbers, for trends. The 2018 year’s survey show whitetail deer density is at an average of 9.6 deer per square mile across the trend areas, which is approximately 10 percent below the long-term average of 10.7 deer per square mile. The 2017 surveys showed whitetails at right at long term average.

“Whitetail deer densities continue to recover in the eastern part of the region, but are still four percent below average, while the densities are still 33 percent below average along the Milk River near Glasgow,” Williamson said.

“A decade ago, whitetail densities were as high as 40-50 deer per square mile in some areas. This was an unsustainable level that was causing problems for landowners and degrading habitat conditions,” Williamson said. “EHD outbreaks and other factors in the following years reduced the whitetail population across Region 6 considerably.”

Although no significant EHD outbreaks have been seen since 2014, areas with higher deer densities along the Missouri River experienced small outbreaks of EHD in recent years.

With whitetail numbers increasing across Region 6, and in accordance with Fish and Wildlife Commission season setting, a single-region antlerless whitetail B-licenses will again be available for over the counter purchase starting August 6, 2018. The licenses will be limited to one per hunter. Additionally for 2018, there will be a limited number of region-wide antlerless whitetail B-licenses available for this fall with applications due at the June 1 deadline.