I know it is only late February, and it is almost impossible to predict what kind of winter this is going to be long term. But from my vantage point living in the woods, I can see that the snow is deep and the weather has been cold. Those are two factors that can really affect the health of our deer herd. I have observed deer over the past week that are belly deep in snow and using a lot of energy to move around.
Winter Severity Index is a measurement used by the Minnesota DNR and other agencies to determine how harsh winters are on animals. The Winter Severity Index (WSI) is determined by accumulating a point for each day with an ambient temperature less than 0 degrees F and an additional point for each day with a snow depth greater than 15 inches. End of season values of less than 100 indicate a mild winter; values more than 180 indicate a severe winter. Going into the last week of January, the snow accumulated in the central part of Minnesota was already over 46 inches where I live. If this wet pattern continues, it will spell trouble for not only deer but turkeys and other animals. The DNR has a website that lists the WSI by county or hunting permit area. It is an excellent way to see how the deer are doing under current conditions.
I remember hunting in the late 60s and early 70s after very harsh winters when it was very difficult to find any deer. I hunted near Effie in 1969 and saw one deer in nine days of hunting. The snow just wiped out large numbers of deer for about three years, forcing the state to close the season in 1971.
It is much too early to predict what the rest of the winter will be like. If it warms up and stops snowing, the deer will do just fine. If it keeps snowing and stays cold, there will be a reduction in the deer herd. Also, the snow fall varies in different parts of the state, so where some deer may be in trouble because of a high WSI, others may be just fine with milder conditions.
The DNR has calculated that 181,000 deer were harvested in the 2019 deer season. This is below the early season estimations, and hunting was really tough in areas where crops were not harvested until late into the fall. Other areas had high water levels causing difficult hunting. The DNR estimates that after the fawns are born each spring, Minnesota has between 900,000 and 1 million deer. A severe winter can greatly reduce those numbers. This one could turn out to be a hard one on deer.