Supplemental Feeding of White-Tailed Deer During Winter
A Position Statement of the Maine Department of Inland Fisheries & Wildlife
The Practice of Supplemental Feeding
Supplemental feeding of deer is gaining popularity in Maine. Practiced primarily during late autumn, winter, and early spring, deer feeding involves placing grains, apples, hay, and other feeds where deer will find and consume them.
A diverse array of people feed deer. Many are suburbanites who feed a few deer; others provide supplemental food to literally hundreds of deer within deer wintering areas. Deer feeding sites are sometimes maintained by municipalities, which commit a portion of their tax revenues to deer feeding, or by businesses that fund deer feeding operations as a cost of doing business.
People are motivated to feed deer for a variety of reasons. They may believe deer cannot survive winter without supplemental food, or they believe that feeding deer in winter will result in a larger, huntable population the next year. Suburban landowners may believe supplemental foods will divert deer away from expensive shrubbery, hence reducing landscaping costs. Others simply enjoy seeing deer at close range. Some business owners know that attracting deer also attracts customers.
The Department acknowledges that most individuals who feed deer are well-intentioned. As the state agency responsible for the stewardship of Maine's wildlife resources, we are compelled to alert Maine people to the many problems that winter feeding may exert upon deer and their habitat.
Some Disadvantages of Supplemental Feeding
Feeding deer in late fall may disrupt deer migration to natural wintering areas.
In early winter, deer normally migrate to preferred wintering habitat, in some cases more than 20 miles from summer range. Deer "short-stopped" by supplemental feeding operations are often more vulnerable to malnutrition, because they do not have access to the right type and amount of foods found in traditional wintering habitat. Also, without the protection of wintering habitat, deer are particularly vulnerable to severe winter weather and predation.
Supplemental feeding may not reduce deer losses during winter.
Predation, not starvation, is the major cause of winter mortality among deer in Maine. Although predators, such as coyotes and bobcats, will selectively kill winter-weakened deer, they are also able to prey upon healthy, vigorous deer. Winter severity (deep snow, intense cold, glare ice on lakes) and the quality of wintering habitat are the real determinants of deer survival in winter. Supplementally-fed deer are still vulnerable to predation, if wintering conditions are severe, particularly where deer are being fed in marginal habitat.
Supplemental feeding may actually increase predation.
Providing a supplemental food source crowds deer into a smaller area than when deer range widely to find food. Concentrated deer maintain a limited network of escape trails, since they often bed near feeders. Deer require extensive trails to elude predators. It is not unusual to observe predation on deer within sight of supplemental feeders.
Deer feeding sites near homes also place deer at greater risk of death from free-roaming dogs.
Family pets that are allowed to roam pose a serious threat to deer, particularly when snow is deep and crusted. Winter feeding operations that concentrate deer in residential areas increase the likelihood that deer will be run and killed by neighborhood dogs.
Deer feeding sites may increase deer/vehicle collisions.
Most deer feeding is conducted near homes, which places deer in close proximity to well-traveled highways. Collisions with motor vehicles near supplemental feeding sites can result in significant losses to a local deer population. For example, at a large feeding site near a well-traveled highway in Maine, 60 to 70 deer are lost to motor vehicle collisions each winter. This loss may exceed the amount of natural losses one would expect, if supplemental feeding were not being practiced in that wintering area. Locating deer feeding sites 1/2 mile or more from plowed roads can minimize road-kill losses.
Deer May Starve When Fed Supplemental Foods During Winter
Deer require one or two weeks to adjust to new foods.
Waiting until deer are starving before offering supplemental foods actually hastens starvation. Stress (related to diet change) is minimized if deer are introduced to supplemental foods early in the winter, when they are still healthy.
Some foods are not easily digested by deer during winter.
Hay of any kind, kitchen scraps, or cabbage and lettuce trimmings do not provide adequate nutrition for deer. Feeding these foods to deer can lead to starvation. Deer usually do well when apples, oats, or acorns are given as diet supplements. However, the best supplemental food is a complete horse, dairy, or deer formulation in pellet form. It contains about 14% protein and provides sufficient energy and fiber to promote normal digestive function in most deer.
Deer compete aggressively for scarce, high-quality foods.
When crowded together, only the strongest, most dominant individuals in the deer population gain access to the food. Frequently, those deer most vulnerable to starvation in winter (usually fawns) are denied access to supplemental feed by more aggressive deer. Distributing supplemental feed in many locations reduces competition among deer.
Deer reject grains or pelleted foods that have become spoiled or moldy.
It is difficult to keep grains dry outdoors. Special feeders, which protect feed from rain and snow, may help, but none are foolproof. Hence, much feed is typically wasted. There are some molds deer may not detect; consequently, they may ingest toxins that can be fatal.
Supplementally-fed deer may die from eating too much feed at one time.
Losses of this nature have been observed at winter deer feeding sites in Maine. Mature bucks seem to be most prone to overeating high-energy supplemental foods.
Supplemental feeding is expensive.
Grains and pelleted foods are sold at a premium price in winter. A deer will consume 2 to 3 lbs of grain each day. Deer seem to be able to communicate the location of "free food" among themselves. Consequently, people who feed a few deer in December often find they are buying food for considerably more deer by February. Some large-scale feeding operators spend $300 or more per week on grain for wild deer.
Once a feeding program is begun, it should not be terminated until spring greenery emerges. Ending a feeding operation prematurely, or providing inadequate amounts of feed, will lead to nutritional problems for deer that have become dependent on supplemental feed. Attracting deer to feeding sites, while failing to provide adequate amounts of supplemental foods can actually cause malnutrition in normally healthy deer populations.
The Maine Department of Inland Fisheries and Wildlife (MDIFW), is sometimes requested to fund, support, or implement supplemental feeding programs for deer during winter. While emotionally appealing to those concerned for the welfare of deer, emergency feeding programs seldom succeed in reducing deer losses during severe winters, and the cost of procuring and distributing feed to several thousand deer wintering areas across Maine would be prohibitive.
Deer concentrations at feeding sites may increase the vulnerability of deer to diseases.
MDIFW has documented deer concentrations equivalent to 350 deer per square mile at some feeding sites. This level of crowding produces ideal conditions for outbreaks of infectious diseases. One such outbreak occurred in 1994 among supplementally-fed deer in Michigan. The highly infectious disease, "Bovine tuberculosis," is currently infecting deer and cattle within 4 counties in Michigan. This disease outbreak poses a serious threat to deer populations and livestock in the affected area.
In Maine, we have documented an outbreak of demodectic mange among deer using a winter feeding site. Demodectic mange is specific to white-tailed deer and is caused by tiny mites living on the hair. Severely infested deer lose their protective winter pelage and are covered with skin lesions. Mange mites are transmitted among deer by close contact, as at crowded feeding sites.
Supplemental feeding may have long-term impacts on the behavior of both deer and the people who feed them.
Deer tend to lose their wariness after prolonged contact with people at feeders.
This loss of wildness in deer diminishes their appeal to many people. Moreover, lack of fear of humans may result in intensified conflicts with people, whether from browsing damage or risk of collisions with motor vehicles.
People's attitudes toward deer change after initiation of supplemental feeding projects.
Those who feed deer often become protective of "their" deer. They tend to lose sight of the fact that deer are wild animals managed in trust for all of Maine's citizens. Concentrating deer at winter feeding sites treats deer more like livestock than wildlife. It is not unusual for overly-protective landowners to quit hunting deer and to actively discourage others from hunting. The desire to protect deer from perceived harm occurs even when hunting seasons precede the time deer are being supplementally fed. As such, the practice of supplementally feeding deer during winter can lead to increased land posting, which in turn, can thwart MDIFW's efforts to maintain deer populations at desirable levels.
Supplemental feeding may increase browsing of landscape plants and gardens.
Even when provided with optimal supplemental foods, deer will continue to browse on shrubbery, tree buds, garden plantings, and seedlings in the adjacent forest. At many feeding sites, deer may occur at densities that are 3 to 5 times higher than "normal" wintering density. When highly concentrated, deer can literally kill all vegetation within their reach in the vicinity (one to several hundred acres) of deer feeding sites. Attracting deer to supplemental feeders in residential neighborhoods may result in deer damage to neighbors' property, because deer usually feed while en route to and from feeding sites.
Supplemental feeding within a deer wintering area can reduce the forest's ability to shelter deer.
Heavy browsing caused by deer concentrated near feeding stations can affect forest regeneration and growth.
Over-browsing of cedar, hemlock, spruce, and balsam fir can destroy or significantly retard the development of critical future winter shelter. Hungry deer can eliminate young hardwood trees, removing important natural winter food. Deer crowded into the areas near feeding sites can eliminate fifteen years of young forest growth in one winter. Few landowners can afford such losses in the productivity of their forest.
Some landowners cut northern white-cedar trees to provide food for deer in winter.
Although this provides highly palatable forage in the short run, cutting cedar trees to feed deer may reduce the carrying capacity of that woodlot for future generations of deer. Cedar does not regenerate following cutting, if deer are abundant. Young cedar seedlings cannot withstand heavy browsing by deer. Over time, the practice of cutting cedar to feed deer in wintering areas will gradually eliminate white-cedar from the forest.
Cedars are long-lived, easily attaining 200 years of age if left uncut.
Each winter, cedar trees drop some of their green leaves when dislodged by snow, wind, ice storms, and squirrel and porcupine feeding. Deer rely heavily on this, and other sources of litterfall, for a substantial portion of their daily browse requirements. Cedar trees are too valuable to the long-term viability of deer wintering habitat to be felled solely as a short-term forage boost. A living cedar tree may provide food and shelter for deer for 100 years -- a felled cedar feeds 10 deer for 1 day.
Preferred Alternatives to Supplemental Feeding of Deer
There are better approaches than supplemental feeding to ensure the health and survival of deer during winter.
The key is to maintain sufficient amounts of high-quality wintering habitat. Rather than expending limited Department resources on quick fixes, such as emergency feeding programs, we will achieve better long-term benefits by ensuring that deer have access to high-quality wintering habitat. This, in the long run, will minimize the effects of severe winters, reduce deer losses during normal winters, and provide for a more sustainable population of deer to be enjoyed by all of Maine's people.
Because deer in Maine exist near the northern limit of the species' range, abnormally severe winters will inevitably cause periodic declines in deer abundance.
In nearly all parts of Maine, deer populations are normally kept well below the capacity of the habitat to support deer. This ensures that deer remain productive, that they have access to high quality forages, and that they achieve
near-optimum body size and condition prior to winter. Body fat provides almost 1/3 of a deer's energy needs while yarded in winter. Fat deer can withstand more severe wintering conditions than lean deer. Healthy, naturally-fed deer do not require a handout to thrive in Maine.
The Citizens of Maine can best help Maine's winter deer herds by:
Taking an active role in managing their lands to improve deer habitat naturally.
MDIFW encourages landowners to develop a management plan for their lands to provide optimal winter and summer habitat for deer. Many wood harvesting practices are good for deer, while also providing income from timber production. Some practices, such as weeding, thinning, crop tree selection, and firewood cutting can provide immediate benefits for deer, and simultaneously enhance the value of future timber sales. Timing one's forest management activities to occur during winter also provides deer with a large amount of natural browse, when they can best use it.
Many other practices improve year-round habitat for deer and other wildlife.
Apple trees can be released from competition to encourage better production of fall foods. Small fields can be planted in cool season forages for deer. Hardwood stands can be managed to favor acorn and/or beechnut production. Wetlands can be improved to diversify forages for deer.
There are a number of agencies that assist landowners who are interested in improving wildlife habitat.
Some agencies offer cost-sharing programs, others provide educational materials and technical advice.
Supporting MDIFW programs that protect and enhance deer wintering habitat. This includes:
- MDIFW's efforts to manage land-use and timber harvesting in the zoned deer wintering areas in Maine's unorganized townships;
- MDIFW's initiatives to negotiate cooperative agreements with large landowners for the long-term management of deer wintering areas for sustainable supplies of timber and deer; and
- MDIFW's efforts to ensure that town governments adequately address the protection of special habitats, such as deer wintering areas, via town-level comprehensive planning.
Working cooperatively with MDIFW to control deer populations in residential areas.
Often, suburban deer are overabundant and pose a nuisance. Providing supplemental foods to overabundant deer populations will not reduce conflicts with people. In developed areas, the usual method of keeping deer numbers in check (recreational hunting with firearms) may not be practical, so landowners are urged to support MDIFW's efforts to implement innovative hunting seasons to reduce deer populations safely and discreetly. This requires homeowners, town governments, and MDIFW to work cooperatively to devise safe and effective ways of maintaining deer populations at tolerable levels.
Allowing deer hunters access to their huntable lands.
This is the most effective means of ensuring that deer populations remain in balance with available habitat, and at levels that minimize negative impacts on deer habitat, farmers, forest landowners, rural residents, and motorists.