Good winter survival numbers so far
A cow elk, collared as part of an Idaho Department of Fish and Game study, moves along a hillside in its winter range. Cow elk are less likely to succumb because of winter weather conditions and predation than calves, according to Idaho Fish and Game. So far this winter though, the number of collared calves that have survived to March is higher than last year. Photo by ROGER PHILLIPS/ Idaho Department of Fish and Game
By RALPH BARTHOLDT
Staff Writer
The number of surviving elk calves fitted with telemetry collars is higher so far this year than a year ago, but the Idaho Department of Fish and Game won’t release official figures until June.
That is when elk calves turn a year old and become yearlings, marking the end goal for calf monitoring.
After that, survival rates increase dramatically, said Laura Wolf, IDFG regional wildlife biologist.
In January, biologists fitted collars on a combined 60 elk calves in Unit 4 in the Coeur d’Alene River drainage and in Unit 6 between St. Maries and Avery. Of those calves, 75 percent have survived 2 ½ months until mid-March, Wolf said.
A year ago malnutrition during a hard winter — along with predation by wolves and cougar — played a role in lower calf survival rates.
“Last year there were a lot of malnutrition deaths in calves,” Wolf said.
By this time last year, the number of collared calf elk had been reduced by 50 percent, she said.
By comparison, winter survival rates for cow elk are high regardless of weather.
“They remain at approximately 94 percent whether it’s a hard winter or a mild winter,” Wolf said.
Wolf said this winter has provided nominal conditions that could lead likely to higher calf survival rates.
“We had snow in November and December; then it warmed up again,” she said. The weather pattern has continued into spring with spates of snow followed by warm weather.
Two years ago, in the winter of 2016, warm weather and moderate snowfall resulted in calf survival rates of around 80 percent, she said.
Statewide collared elk calf numbers are also doing well thanks to a relatively normal winter, said Roger Phillips of IDFG, which also monitors collared mule deer fawns.
“More young deer and elk are surviving this winter, which will likely grow herds and produce more game for big game hunters next fall,” Phillips said.
Of the 244 collared mule deer fawns and 246 collared elk calves that biologists are monitoring statewide, 88 percent of the fawns and 97 percent of the calves have made it to March, compared to 55 percent of the fawns and 80 percent of the calves that survived last winter, according to IDFG.
“Less snow at lower elevations, and warmer temperatures means fewer animals are likely to die from malnutrition, predation and other factors that increase mortality during a difficult winter,” Phillips said.
This winter has been pretty normal, he said, and so far no extended periods of cold weather coupled with deep snow have been documented.
“When it turns into a month, and it crusts over and they can’t dig down through it, that’s when we start seeing problems,” Phillips said.
By early March young animals are still vulnerable, though, especially animals weakened by winter. Those animals may have difficulties transitioning from browse to green grassy shoots.
“March and April is when we normally see the highest mortality,” said Daryl Meints, the department’s deer and elk coordinator.
Barring a surge of cold spring weather, survival will likely be much higher than last year. Statewide, just 30 percent of collared fawns and 54 percent of collared calves survived last winter, which was among the lowest survival rates in the last two decades.