Heavy Snow Reduces Annual Deer Mortality Survey Efforts

Send by email Printer-friendly version Share this

Heavy snowfall, poor visibility, and bad roads reduced the number of volunteers participating in the Game and Fish Department’s 12th annual deer mortality surveys May 7-8 in southwest Wyoming.

Cokeville Game Warden Neil Hymas said this was the first year that weather essentially stopped the survey, with the exception of a few hard core participants that insisted on getting wet.

“We had eight people that rode horses or walked to locate dead deer for us even though blizzard-like conditions persisted all morning,” said Hymas. “Another five people showed up but decided against participating in the survey due to poor weather conditions, and we don’t blame them a bit.”

Thayne Wildlife Biologist Gary Fralick has coordinated the mortality surveys for several years and says fortunately, most of the deer had migrated off the core winter ranges by the first week in May.

“We were due for this one,” says Fralick. “This is the first year in the 12 years of these annual mule deer mortality surveys that the effects of a severe storm forced the cancellation of the entire survey effort. We believed conducting the surveys under such adverse weather conditions and with a just a few volunteers would not have been comparable to previous surveys when 45-75 people volunteered.”

Hymas and Fralick believe they have a pretty good handle on what to expect with mule deer mortality in the Wyoming Range.

“I think it would be safe from observations from field contacts with the public, and our spring classification efforts to determine change-in-ratios of fawn to adult deer, to note that there was a difference of mortality within the winter range complex,” said Hymas. “A portion of the winter range that is located from roughly Cokeville south to the Crawford Mountain range experienced considerably above normal fawn mortality. This includes winter ranges locally called the Rock Creek and Bridger Basin winter ranges. However, winter conditions were much more moderate on the LaBarge and Daniel winter ranges, and as a result over-winter deer survival was much higher in these areas.”

Heavy snows that accumulated over a short period in January blanketed the Rock Creek and Bridger Basin winter ranges. Cold temperatures and windless days allowed the snow to remain deep later than normal in this area, and caused significant stress on wintering deer, especially fawns.

Kemmerer Wildlife Biologist Ron Lockwood said deer managers are concerned with both winter impacts and impacts from spring weather.

“Mortality in my region ranged from heavy mortality in the Cokeville area to average near Le Roy and Evanston,” said Lockwood. “What you have to consider are those late spring storms with snow and or rain that really add to the mortality.”

Other winter ranges around the Wyoming Range Deer herd unit experienced mortality in ranges from average to slightly higher than normal.

Baggs Wildlife Biologist Tim Woolley says mule deer experienced a relatively mild winter in the Baggs area.

“I estimate that we lost approximately 10 percent of the deer fawns,” said Woolley. “When I did the spring deer classifications I looked for carcasses and I found very few.”

Green River Wildlife Biologist Grant Frost found little to no change in deer ratios.

“Elk Mountain, between Farson and the Wind River Mountains is surveyed every spring with help from students of Green River High School for deer winter mortalities,” Frost said. “A spring survey in April, before the current wet cycle started, indicated little change in the ratio of fawns to does counted in post-season classifications in late fall, 2004. Wet conditions increased travel time to Elk Mountain, so there was less time available to survey.

“Very few deer mortalities were seen (11 total, 7 fawns, 4 adults) supporting the observations from April. Overall, it appears that deer within the Green River biologist district (South Rock Springs, Uinta, Steamboat and the extreme south end of the Wind River Mountains) fared well this winter, and the spring moisture we have received should do wonders for range conditions and deer herd health.”

Fralick says it will be important to mark next year's calendar for May 6-7 to ensure the survey is continued. “It’s real easy to remember that we do these surveys the first week of May each year,” Fralick said. “We have a large following and a group of dedicated people from Wyoming and Utah that help out each year. We thank all the volunteers who help, and especially the tough ones that showed up in 2005.”