Winter-weary Wildlife

by Cat Urbigkit

This could be the year the worst-case scenario comes true.

Conditions are right for a major winter wildlife die-off, according to Wyoming Game and Fish Department officials.

WG&F Regional Wildlife Supervisor Bernie Holz said he suspects that the over-winter kill could be as high as that in the winter of 1992-1993, when 70 percent of mule deer fawns of the year perished.

Holz said snow has been persistent, with winds "packing it into the sagebrush pretty hard and there's not much sticking out above it."

"I think it could be really similar, if not worse, than the winter of '92-'93," Holz said, citing that winter as the last big ungulate die-off for this region.

Holz said while people may have a hard time envisioning it, that winter was similar to this one, with normal precipitation following a period of extended drought. The result was the 70-percent loss of fawns, as well as depressed birthing rates for doe deer that spring.

"The does didn't have live births," Holz explained. "We lost almost two cohorts of reproduction," meaning both the fawns of that year died, in addition to the upcoming fawning that simply didn't occur.

Most antelope have simply left the area, with few antelope remaining north of Highway 351, Holz said.

"They outrun the deer in their migration," he said.

With little or no leader growth on sagebrush last year, mule deer are consuming very old plant matter in an attempt to get adequate nutrition.

"We're starting to see some deer die off now," Holz said, describing deer curled in their beds of snow, with necks out-stretched and ears down. Extremely cold temperatures at night add to the condition in which the animals never again arise from their beds. An aerial flight last week by area research biologist reportedly revealed dead and dying deer in the Mesa area and along the Wind River Front.

Holz cautioned that people need to practice restraint in terms of feeding wildlife. With starving deer, for the most part, "you can't save it by feeding it," he said, because starving deer lack the rumen bacteria to process the feed. That's why deer die with their guts full of concentrates from which they were unable to get needed nutrition. The rumen bacteria changeover takes time to occur, making deer feeding rarely effective at saving animals.

WG&F will take another look at the deer population just before migration begins. Holz said WG&F will conduct an age class survey in which the agency will determine the adult:fawn ratio. The data taken in early April will be compared to December survey information to give the state wildlife agency an indication of the fawn crop loss. In addition, in early May, WG&F personnel and volunteers will conduct a survey for deer carcasses, providing information on over-winter losses.

The winter die off sets the stage for another debate over deer management. WG&F will once again be faced with a contingent of people calling for very conservative hunting seasons to be set in order to quickly rebuild deer populations. That will be countered with the question of whether such action is wise, considering how the wildlife habitat cannot handle such large populations in its present condition.

"Those winter ranges are really drought-stricken," Holz said, "and now they are getting pounded by the ungulates. There has been no sagebrush growth in several years, so whatever they're eating is just sticks.

"Do we wait until we see an improvement before we allow these ungulate herds to bounce back? What do we do?" Holz pondered.

Within the last two weeks, there has been a great deal of wildlife activity being noted by Sublette County residents. Ducks are seen near available open water, as are a few kingfishers, and other open-water avians. Skunks have been seen emerging from winter dens around the county as well. Other den-dwellers out in recent sunshine include prairie dogs.

According to Holz, these critters are two months too early for spring. He fears that the animals went into winter quarters in such a condition that they are now coming out of their dens prematurely seeking food. He noted that a young black bear had to be killed a few weeks ago in the Jackson area for just such action, with the animal in very poor shape.

On the brighter side, elk herds are expected to do well. Most elk in this region are associated with elk feedgrounds, where hay is fed to sustain the herds. Mortality in elk would mostly be elk calves, and having elk on feedgrounds completely offsets the calf mortality, Holz said.

"Elk are doing really well," Holz confirmed.