Feeding deer in winter may be more harmful than good

When hard-crusted snow covers the ground, wildlife have a tough time finding food. Deer in particular have trouble finding suitable forage. As such, many well-meaning folks put out bagged corn or grain. While commendable as it appears, their graciousness is only harming the species.  

According to the Pennsylvania Game Commission, artificially feeding deer in the winter is the best way to kill a large number of deer in a small area in a short time. The problem, says the PGC, is that a deer’s diet cannot be rapidly changed in winter without damage to its digestive system. 

Deer, they say, have a four compartment stomach that relies on microbes for digestion. The types of microbes change gradually in early winter to digest woody browse and again in spring to digest green vegetation. 

Illnesses such as acidosis and enterotoxemia often result when the winter diet is suddenly switched to simpler, more digestible carbs like corn or grain. Enterotoxaemia occurs when these carbs cause bacteria to bloom in the deer’s digestive system. This bacteria is beneficial during normal feeding events, but too much releases a neurotoxin that is absorbed into the blood which results in death, as explained in a PGC booklet. 

A prime example of this was explained to friends, who at one time resided outside Pennsville in Northampton County. What appeared to be a dying button buck that hung close to their house, necessitated a call to the local WCO for Northampton County. After addressing the visibly infected yearling that was apparently wounded during the hunting season, the WCO recalled being summoned to a home to pick up a young dead deer that was lying atop a corn pile. 

This goes to explain that it takes a deer time and energy to convert to new microorganisms, like that found in bag corn and grain. During that time, it uses precious fat reserves that could have been spared if the deer had fed continually on natural winter browse, says the agency.  

The PGC points to studies that have shown that deer can die from feeding on highly digestible, high energy, low fiber feed such as corn in winter. This rapid exposure to a concentrated grain diet can cause a fatal disruption of the animal’s acid base balance. Deer that survive the immediate effects of “grain overload,” often die in the days or weeks that follow, due to secondary complications of the disease. 

Evidently this is what happened to the deer found atop the corn pile. And young deer are more susceptible since they are the last ones to feed after the larger, older, stronger deer eat first. 

Another point the PGC makes is that supplemental feeding sometimes congregates deer in unnatural densities. Luring large numbers of deer in a small area could create a risk for spreading CWD, tuberculosis and in wild turkeys that feed on “deer corn.” 

The PGC concludes that supplemental deer feeding during hard winter months increases the winter death rate by 25-42 percent. They recommend planting certain trees, bushes and maintaining autumn food plots instead. That, and felling firewood trees in late winter puts deciduous tree-tops where deer can reach them. 

To read more on the subject check “Winter Feeding of Deer and Turkey,” a 26-page document available on the PGC’s website www.pgc.state.pa.us.  Click on “Wildlife” on the left, then scroll down to the “Wildlife Reference Guides” section to view the digital booklet. 
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