Whitetail Deer: How To Minimize Winter Kill

marrow

Left: Evidence of malnutrition in the bone marrow of a whitetail fawn.

A couple of weeks ago, we reported that despite the severe conditions this past winter in the Northeast, deer biologists were remaining somewhat optimistic about winter deer mortality. That said, we should remember that state biologists typically look at their deer herds from a macro level and conditions may be entirely different on your little piece of deer hunting paradise. The axiom, about how all deer management is local (if not site specific) is especially true in cases of winter deer kill and disease. What happens on and around the 100 or 200 or 2,000 acres you actually hunt is more important to you as a hunter than what may be happening across the state.

A close friend called last week to report finding four dead fawns while he was shed hunting. They appeared to be winter-kill casualties: they were found close together in classic winter cover, and their bone marrows had the tell-tale signs of starvation (dark jelly-like liquid). My friend was pretty bummed. He had gone out for sheds and came back with dead fawns. The area he hunts had recently turned into a deer paradise. Big deer sightings were commonplace and he and his wife had the mounts to prove it. What he failed to think about in his management plan was what would happen to his deer once the corn and beans were in the silo. Each winter, the burgeoning herds consumed more and more of the winter food and cover. This year, with limited deer movement, it caught up with them. Too many deer, not enough to eat in winter: a classic example that shows deer management is site specific.

While you can’t control weather, you can manage what winter delivers to your deer herd. For starters, get out in the woods as soon as the weather permits to get a handle on deer mortality. If you find an inordinate number of carcasses (remember, some deer always die in winter), check the bone marrow and report the situation to your state deer biologists. They will need to factor this information into their doe harvest goals for next year.

Statewide regulations aside, factor what you find into your own management philosophy. You may not need to quit shooting does entirely, for example, but you may need to be on the lookout for a lower than normal number of deer in the woods next fall.

Next, do some survey work with a spotlight (where legal), or by staking out food sources in August and September to check your fawn recruitment rate. If you see one fawn for every 2 to 4 or more does, your recruitment rate is quite low. One to 1 1/2 fawns for every adult doe is about normal for most areas. If you seem to have had a relatively decent recruitment year, go ahead with your normal doe-harvest guidelines.

Perhaps more importantly, if you suffered excessive winter kill, you need to be thinking about preventive measures. Two or three tough winters can devastate a deer herd. What we are talking about here is habitat, the ultimate deer-hunting intervention strategy. If your deer had a killer of a winter, get out there with a chainsaw and open up some dark timber to let in some life-sustaining sunlight. Use some foresight when planting food plots and put in crops that can sustain deer through the tough winter and early spring. Standing corn and beans will help through winter while clover provides early protein in the spring.

I followed up with my buddy on the dead fawn report a few days later and he had gone back and looked over the winter habitat they were found in. He reported that every inch of browse that could sustain a deer in winter had been eaten. The small fawns couldn’t reach what little was available and, of course, there was nothing to be found under 2 to 3 feet of snow. He resolved to get busy and create more and better natural winter browse in the areas that border the crop fields.

Nobody likes winterkill, except maybe the coyotes. But it is real and takes its toll somewhere every year. State agencies adjust harvest goals after a severe winter, but that only goes so far. Landowners and hunters can do plenty. If you suspect a higher than normal winter kill in your hunting area, then your deer management journey is just beginning.

To read about winter kills and feeding deer, click here.