There’s little chance that would happen anyway, as a wild whitetail burns enormous amounts of calories evading predators, breeding, fighting, raising fawns and simply trying to survive. Therefore, deer seek food sources that supply nutrients they need for survival. Throughout a deer’s yearly cycle, those nutritional demands change based on biological functions and environmental conditions. For example, the nutritional needs of a buck or doe are different in summer than they are in the winter, so to maximize nutritional supply, you should manage your deer nutritional program to meet each demand.
Late Winter, Early Spring I like to begin the discussion of a deer’s yearly nutritional cycle with the relatively brief but extremely important time when winter is waning but still holds an icy grip on the whitetail’s world. The exact timing varies based on geographic location and annual fluctuation of temperatures, but it involves the final few weeks leading to spring green-up. In the Midwest during a typical year, that encompasses the latter part of February through early April. That’s a small window, but it can be one of the most stressful in a deer’s annual cycle. Quality food supplies are typically in short supply — in fact, lower than at any other time. The nutrient-rich vegetation that accompanies spring green-up has not yet sprouted, and in most cases, winter food sources have all but disappeared. Does are entering their last trimester of gestation, which is when the most fetal growth occurs. Early in gestation, poor nutrition can lead to fetal reabsorption or abortion, but during the final weeks of pregnancy, nutrients consumed and from body reserves are routed to the unborn fawn — even to the detriment of the doe. If good nutrition is not available, a doe’s health and body condition will suffer and can cause low birth weights and decreased post-natal milk production. Those conditions dramatically decrease fawn survivability. Also during this time, newly formed antler buds are just starting to appear on a buck’s pedicles. Although protein requirements are not as high as they will be during the peak antler growing season in late spring and summer, protein needs increase from winter requirements to support the new antler growth. A shortage of protein during this stage can stunt early antler growth and negatively affect eventual antler size. Like does, bucks are often in poor body condition coming out of winter and in need of high-energy food sources. Increased nutritional needs combined with the lack of those nutrients present a serious threat to the health and quality of a deer herd. However, you can take steps to help manage the problem. One option is to use a free-choice supplement (where they are legal) that contains highly digestible protein and energy sources. Typically, these supplements also contain minerals and vitamins, which are nutritionally important, although not to the extent as they will become in late spring through early fall. It’s important to use a supplement that has been scientifically developed and formulated specifically for deer and for this time frame. Whitetail Institute’s 30-06 Thrive is a great example. You can also plant enough winter forage to supply a food source until spring green-up. To do so, you must have a good estimate of the herd size, the amount of tonnage the forage will produce and how long you need it to last. Plug those factors into your equation and you will arrive at the acreage required. For example, let’s say your estimated deer herd size is 50, and you think each animal will eat 2 to 3 pounds
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Late winter and early spring can be very nutritionally stressful for deer. Protein needs rise as bucks begin antler growth and does enter the third trimester of gestation. Having a food plot that greens up quickly, like Imperial Whitetail Clover is very important. Photo by Matt Harper per day. If you average 4,000 pounds of forage per acre and want to supply food from Oct. 15 through April 1, you will need to plant about 5-1/2 acres (50 head times 2.5 pounds per day times 170 days/4,000 pounds per acre). Of course, that’s not an exact science and can be affected by forage production, year-specific temperature and climate, attracting more deer from adjacent properties and other factors; but it provides a good rule of thumb. I will go into more detail on what to plant when we discuss fall and winter nutrition. Finally, the sooner spring green-up occurs, the better. You can do nothing about the timing of natural food green-up, but you can consider that factor when planting food plots. For example, Imperial Whitetail Clover and Imperial Whitetail Fusion are extremely cold tolerant, which means they will stay green longer in winter and also green up sooner in spring.
Spring and Summer Spring and summer are a time of plenty in the whitetail’s world. Natural vegetation is at its highest nutrient level, as most plants are vegetative and growing. It’s nature’s design to have the most abundant food supplies coincide with the birth of offspring. This is also when nutritional needs are at their peak. In most parts of the country, does give birth in late spring, and milk production drives the need for the highest quality and quantity of food sources. Protein requirements for a lactating doe are about 18 percent, and the energy needs are at the highest in her yearly cycle. Mineral and vitamin needs are also at their highest levels. Doe’s milk is extremely nutrient dense in that it has a higher fat and protein content than cow’s milk. If a doe’s diet is lacking in quality or quantity of nutrition, it will not change the composition of the milk but rather the quantity she produces. Optimal milk supply is critical for fawn survivability, especially for the first few days and weeks after birth. A healthy, strong, growing fawn has a far greater chance of making it through those first few days when mortality rates are at www.whitetailinstitute.com