September 08, 2017
By Dr. James C. Kroll
Supplemental feeding for whitetails is certainly near the top of the list of "hot button" issues in deer management. Many are asking: Is there a place for supplemental feed in a whitetail management program? To answer that question, let's take a closer look at what constitutes a well-balanced diet for whitetails and how supplemental feeding can help the deer you're managing on your property.
FEEDING VS. BAITING
There is a huge difference between feeding deer as part of a sound management program and trying to bait them into a place to be shot. The purpose of the latter is obvious: The hunter wants to put the odds in his favor. This may not be legal depending on what state you live in, so you need to research your state regulations carefully. But the purpose of feeding deer (where it is legally permitted) should be to balance out the nutritional needs of your deer, in the context of a sound nutrition program.
It is always critical to use natural forage as the basis for your nutritional program, but if it's legal in an area, I add in supplemental feeding to fill in the nutritional limitations caused by such things as climate and soil.
Once you have your herd "clicking" at optimum recruitment, the next step is supplementation. Most of the time, sub-par nutrition is the most limiting factor to better antlers and fawn crop. There are two ways to supplement nutrition -- food plots and supplemental feed. Food plots certainly are the least expensive way to supplement, since a pound of food plot forage costs about 2 cents, while feed averages 35 cents per pound. Yet, there are many areas where it is not possible to grow food plots or where there normally is adequate rainfall, there is always the specter of drought! So, even for properties with the climate for food plots, I usually include supplemental feeding (where legal).
WHAT MAKES A GOOD DEER FEED?
A good deer feed should supply protein, carbohydrates, fats and minerals at proper levels, but based on the inquiries I receive, land managers are most curious about protein levels.
We classify any nutritional need of whitetails into two categories: maintenance and optimum. The maintenance level is what it takes for a deer of a certain age and sex to get by. Conversely, when you are managing your herd to produce the best possible antler growth, you need to know what is optimum.
Whitetails not only are marvelously adapted to making do with little, they also have the ability to "overlook" excess. Most studies have demonstrated time and again, that the optimum protein level for the average deer is around 17 percent crude protein. The older a deer gets, the less protein it needs. Fawns and yearlings often need a higher percentage of protein.
Unlike humans, whitetail deer want to be fat! Deer will utilize what amounts to a reverse Atkins diet, stocking up on carbohydrates in forms like the sugars cellulose and hemicellulose to create fat reserves that can be easily used for energy when needed. So, a feed with adequate protein and carbohydrates will allow deer to do quite well.
So, a feed that is 3- to 4-percent fat is adequate. A good rule-of-thumb is to balance fiber content against protein. For example, if a deer feed offers 17 percent protein, you should have 13 to 15 percent fiber.
THE IMPORTANCE OF MINERALS
Whereas protein tends to get the most attention, minerals are perhaps the most overlooked feed component. The mineral needs of whitetails often are different from those of domestic livestock.
Of the host of macro- and micro-nutrients needed by deer, the two most critical are phosphorus and sodium. Sodium is important for many physiological activities, such as electrolyte balance, muscle and nerve conduction, blood buffering, etc. There have been solid scientific studies indicating body size, antler development and fawn production are tied to dietary phosphorus. Calcium, another critical mineral, affects phosphorus availability, with the ratio of these two minerals in food just as important as the amount of each present. In general, a 2:1 to 1:1 calcium-to-phosphorus ratio is optimal. The actual amount of phosphorus needed depends on sex, age and season, but it's thought to range from 0.2-0.4 percent in the diet. This said, we recommend higher levels of phosphorous and calcium in our feed, since it is a supplement.
Micro-nutrients such as zinc, selenium, copper and cobalt can be limiting. We use the term "micro-nutrients" to emphasize they are needed in small quantities. Selenium is a great example. This mineral is critical to cell division, sperm production, antioxidant enzymes and antler development.
As you can see, providing a quality feed to whitetails is not a simple matter. There are many good deer feeds on the market, and I urge you not to tinker with deer diets by concocting your own "special formula."
Remember: all of the elements that make up an optimal whitetail diet are important, but rather than focus on individual pieces of the dietary puzzle, it is much more valuable to seek out a balanced ration!