Winter Deer Feeding: More Harm than Good?

December 6, 2017 | by Thomas Ham

Save the Deer

It will soon be that time of year. The metaphorical warmth of the holiday season gives way to the literal freeze of winter; commutes in the dark, rock salt and extra layers become commonplace for northern residents. 

As we adapt to face the grips of winter, so too must wildlife. Deer, our nation’s most sought-after big game species, put on a clinic of winter survival.

An animal of prestige, deer are largely responsible for our continued tradition of hunting, yet are increasingly viewed by the non-hunting public as ornamental and not as a natural resource. And so, winter feeding becomes inevitable.

Backyard feeders surrender to unnecessary pity for wild animals, motivated to feed them in an attempt to save them. In the case of deer, they maintain their blinders to the well documented health risks winter feeding poses, specifically rumen acidosis (a rapid introduction of high carb, low fiber foods which conflict with micro-organisms in deer stomachs, disrupting digestion and causing dehydration, which can lead to death).

A Google search reveals cases of deer and elk succumbing to acidosis are not uncommon. Wildlife authorities often plead with the public to let the animals deal with winter on their own, that instincts and adaptations are far more effective than supplemental feeding, which alters behavior and may have fatal results.

But alas, the heart speaks louder than science.

It’s Everybody

Hunters aren’t exactly blameless either.

Many hunters resort to feeding to keep deer interested in their property, which if done legally, is not the worst thing imaginable. The issue is, many do not start feeding until after hunting seasons end, typically in winter months, when deer have already adapted to harsher conditions.

You either keep the feeder full all year round, or never put it out in the first place.

In addition to acidosis, a handful of major risks come with food piles. Congregational feeding sites increase the likelihood of ingesting infectious fecal matter and other bacteria, accelerating the spread of disease. Feed sites alter natural grazing behavior leading to competition and ostracizing younger or subordinate deer. Food piles invite other species to the party, and some dinner guests can transmit diseases, such as rabies.

Despite all of that, there are those who still participate in winter feeding.

The cheapest and most accessible winter deer feed is corn. It’s all too easy to walk into a local feed, big box, or sporting goods store and find large bags of “Deer Corn” for little more than you’d pay for an Arby’s value meal. One cannot help contemplating how ridiculously obtainable these products are, somehow defusing the conscientious whisper to avoid using them.

Those with ambition to retain deer on their hunting grounds often fail to realize the potency of, and dangers to, the existing habitat. Enticing deer to food piles risks over grazing of surrounding natural browse. Not only does this reduce food sources that attract deer all year, but it leaves the area susceptible to invasive or inferior flora, which might actually deter deer.

When it’s Necessary

With the many downfalls of winter feeding, can there be an upside?

In 2014 the Minnesota Deer Hunters Association (MDHA) worked in conjunction with the Department of Natural Resources (DNR) to execute an emergency winter deer feeding program. An assessment of the Winter Severity Index (WSI) by MDHA indicated a high risk of herd fatality without supplemental feeding. WSI was developed in the 1970’s and calculates the number of days with 18 inches or more of snow pack combined with the number of days at sub-zero temperatures.  The WSI for northern Minnesota in 2014 was projected to reach 100 (very severe) by mid-February, so the DNR approved the project, and funded it through an earmarked purse built by a 50-cent per deer license fee established in 1996.

MDHA assembled a volunteer force and feed contract to place over 500 tons of food throughout the northern tier of the state. MDHA staff and volunteers combined for 2,613 man hours of labor over a six week period, starting their project on a $170,000 budget, which received a much needed boost of $90,000 in week five. 

“Our volunteer force was great,” says MDHA Grant Coordinator Jenny Foley, “they did anything and everything to help, even coming out in snowmobiles and snowshoes!”

Foley, who was the MDHA point person for the project, recalls convincing the DNR to approve the project, which took weeks amidst concerns over winter deer feeding. In retrospect MDHA feels an earlier start would have been better.

According to Foley, the DNR required that their food formula be used, even though it contained cracked corn.

“Our director was familiar with acidosis risks and pushed for a different formula, but the DNR stuck with their pelletized feed.”

Volunteers witnessed deer yarded up by the hundreds, begging the question, if the spread of disease was a risk, wouldn’t it be imminent? That many deer confined by snow pack could be susceptible to pestilence, as well as predation.

The project fed an average of 17% of the deer population in selected feeding areas containing an estimated 97,000 deer.

The food required by a project of that magnitude would be a nice hit for any one feed mill, but Foley asserts “the 528 tons we placed was a drop in the bucket compared to recreational feeding.”

The feed supplier and local business distribution centers reported a positive impact to their bottom line, and the MDHA reports a positive local economic effect overall.

Obviously the Minnesota winter of 2014 was an extreme case and the project was recognized as being a short-term solution to an atypical problem. Feeding was thought to be beneficial only in the absence of communicable diseases. However, with Minnesota now officially on the board with CWD, recreational feeding, or any feeding, may be banned in certain areas.

Even so, QDMA Director of Conservation Kip Adams maintains there may be better options.

“It’s hard to say if the benefits outweighed the risk,” says Adams, “It is popular with the public (winter feeding), but it’s probably better to spend the money on habitat.”

Adams recalled his experiences in New Hampshire, which also encounters devastating winters and deer losses are usually minimal.

Overall Adams feels any congregational sites could hurt as much as help the deer population, and habitat improvement gives you more bang for your buck. He suggests a creative one-two punch by felling trees the deer feed on.

“Species like the red maple are great for deer, they can feed on the buds and the downed tree provides cover,” says Adams, “and now more sunlight will come through encouraging new spring growth also providing nutrients.”

Mineral Supplements

Most hunters pass on the task of dragging 40 pound bags of corn to the stand or trail camera locations, but won’t think twice to place smaller quantities of mineral supplement there. The ultimate question becomes, is it any better or worse than food piles?

AniLogics brand mineral supplements touts a product line offering a proprietary, all-year feeding strategy, giving deer what they need when they need it.

The winter phase of their supplement strategy is advertised to boost deer immune systems. For AniLogics, the concern for wintering deer is whether they’re getting a balanced diet with access to energy and protein.

“Vitamins and micro-minerals are deficient in nearly all non-supplemented deer,” says Reed Leiting, DVM, and AniLogics Director of Nutrition, “There is a big difference between surviving and thriving. Without all aspects of nutrition the immune system cannot work at its best.”

A point that is true for many organisms, even mild deficiencies alter immune responses; micronutrients and vitamins all have sway over the body’s ability to stave off illness.

Leiting does see a benefit to minerals use over food piles since most food sold is grain based, which may have an effect on energy, but is low in protein and doesn’t address a cervid’s need for vitamins and minerals.

Leiting and AniLogics believe supplementing deer diets is an important part of deer management, and their studies of non-supplemented deer livers have never shown adequate levels of micro minerals.

It seems however a large driver of AniLogics, and likewise other supplement brands, is to assist the deer in reaching their genetic potential. One needs to distinguish the importance of that. Since the dawn of the species, deer have survived winter severity, famine and predation without our help.  But man-made supplements arguably offer the herd a chance to flourish.

Should we? Some say no.

“Mineral licks pose the same risk as feeding with regard to disease transmission,” says Jeannine Fleegle a Pennsylvania Game Commission Biologist, “It congregates deer and they are all licking the same source.”

Nevertheless, promising bigger racks and more frequent visits, mineral supplements captivate hunters.

Ultimately mineral products aren’t bad for deer. In many cases they contain well thought out ingredients, and most reputable brands study product results. It is important for hunters to understand the differences between minerals and attractants, the latter often equates to simply luring deer in with unhealthy candy.

A Bigger Picture

An important question to ask this winter is ‘What is my goal in supplementing deer diets?’ Be honest.

Keeping a deer on your property? Growing antlers? Encouraging them to make routine stops in close proximity to your stand?

It’s likely that winter supplementation boils down to an egocentric desire of a hunter, not the betterment of the local deer population.

Entirely possible is an altruistic motivation for supplementing deer diets - even then it isn’t necessary.

“The short answer is deer do not need us to supplement their nutrition,” Says Fleegle, “A balanced deer herd in a healthy habitat provides everything a deer needs.”

That thought, embraced by many deer experts, doesn’t mix well with the marketing aspect of hunting. But the hunting industry’s desire to grow deer and recruit hunters is a subject best left for another article.

When it pertains to deer this winter, savvy hunters will focus more on habitat, woodsmanship and scouting. Backyard feeders and hunters alike might consider researching plant species which offer cover and winter browse.

The 40 pound bag of “Deer Corn” might be cheap and easy, but deserves a second thought.

Stay warm.


About the Author: 

Thomas Ham is an outdoor writer from Wyomissing, Pennsylvania who regularly contributes to his local paper and has been featured in other PA outdoor periodicals. He can be reached at [email protected]