Wisconsin biologists say that the combined snow and cold of this year’s winter makes it the state’s worst in nearly 20 years for deer. Like other states hit hard by the arctic freeze, Wisconsin’s deer population is struggling to find enough food to survive to spring.
“You take a look at them, all their reserves are depleted and it’s quite likely that they succumbed to winter starvation,” Wisconsin Department of Natural Resources (DNR) wildlife supervisor John Huff told Fox 11.
Deer are robustly built animals and usually weather the winter season by surviving on accumulated fat. However, an especially rough winter can tax the animals to their limits. A rough winter will kill weak and old deer, while pregnant does also come under distress and produce less fawns.
“They have a low birth rate, sometimes the does resorb their embryos and they never have fawns,” said Huff.
Wildlife officials measure each winter’s effect on deer using what is known as a Winter Severity Index. Researchers calculate a rough measure of how severe each winter is by snow depth and temperature. DNR biologist Jeremy Holtz told WXPR that an Index score of 50 points or under is considered mild, whereas a score between 50 and 80 is considered moderate and a score above 80 is severe.
“Right now we are past 100 in most WSI measurements,” Holtz said. “Winter is slow in relenting. Our deer population was well below our established over-winter goal before deer season, so you can expect very few, if any, antlerless deer tags to be issued (in north Wisconsin) next fall.”
The biologist added that the deer in the Laurentian Mixed Forest, also known as the North Woods, have been especially hard-hit. The 30-year average for this region hovers around 67.
Some states, such as Minnesota, are responding with emergency deer feedings. However, some biologists say that this method is ineffective and can promote disease. Wisconsin DNR officials have said that the full effect of this year’s severe winter will be more evident as spring nears.