Deer Nutrition & Food Habits | Deer Hunting & Management

Poor Nutrition: Doe Eats a Fawn?

Whitetail Doe Eats Fawn?!?

White-tailed deer have specific nutritional requirements that can be met through habitat management and by maintaining deer numbers at the carrying capacity for the area. Under these described conditions, deer can get all of the required components of their diet, including energy, protein, fat, vitamins, and minerals, that allow them to function properly. Many deer managers will even provide supplemental forage in the form of protein pellets or food plots that allow for optimal deer performance and health.

But what happens when a deer’s diet does not meet their dietary requirements? The answer is simple: Deer suffer. This suffering comes in the form of lower body weights, poor body function, lowered immune systems, and sub-optimal antler growth. As far as deer are concerned, the latter is the least of their worries.

Malnourished bucks will “steal” necessary vitamins and minerals from antler growth to supply critical processes. Does will do the same sort of thing, but malnourished does will abort their fetuses during pregnancy or abandon their fawns during nursing. In short, deer that have poor diets will do things you may not expect. Such is the case in these photos of a white-tailed doe eating a road-killed fawn.

These photos are from an suburban area with a high population of white-tailed deer located near Austin, Texas. And by high, I suspect that the deer density in this area is approaching about 1 deer for every 1 to 2 acres. I don’t care where you go, that’s a very high deer density! To make matters worse, this part of Texas has been under severe drought conditions for the past year. Although high numbers of deer exist in suburban areas throughout the United States, poor environmental conditions can exacerbate the problems associated with deer overpopulation.

One deer for every one acre: I hope that no ranch ever attempts to have this many deer on a property. In most parts of the country, a good rule of thumb is 1 white-tailed deer for every 6 to 12 acres of deer habitat, depending on soil and precipitation. In central Texas, a deer would require a minimum of 8 acres of good habitat to meet its dietary requirements and achieve optimal growth. Because the doe above is found in a suburban area where deer numbers are difficult to maintain (because hunting is not allowed), the the animal can not possibly have a proper diet. The “habitat” is inadequate and, as a result, so are the food sources.

READ: Can Deer Get Mastitis?

Over the years, researchers and observers have reported that white-tailed deer are not strictly vegetarian. In areas where their normal diet is low in essential minerals (particularly calcium) deer have been reported to eat meat, in addition to bird eggs and young birds (whole) found in nests. These unusual additions to the diet are believed to be consumed when minerals are lacking, although actual vitamin requirements in whitetail are unknown, as well.

Obviously, the whitetail doe featured in these photos is not in horrible shape, but she is far from great condition. This doe was reportedly observed eating meat directly from the road-killed fawn. Although meat does not normally comprise the food habits of whitetail, this doe sensed that something she was lacking could be garnered from the flesh of this dead fawn.

Fire Creates Better White-tailed Deer Habitat

White-tailed deer, like many wildlife species, prefer habitat that is at lower successional stages. Simply stated, deer like plant communities that are dominated by plants that are considered first responders after disturbance. Any disturbance helps set back plant succession, whether it be disking established areas, clear-cutting portions of forests, or natural or prescribed fire. And although hunters understand that deer management practices are designed to improve habitat, many habitat management practices are really only designed to mimic processes that occur naturally.

Of course, when it happens naturally land managers have very little control. Such was the case last year in Texas when the almost 15,000 acre Chaparral Wildlife Management Area (WMA) unexpectedly caught fire. It was March of 2008, but because of extremely dry spring conditions, a fire that started adjacent the area burned 95% of the state-owned WMA! Anyone that knows anything about the Chaparral WMA knows that the area is representative of South Texas brushland, but active habitat and deer management practices maintain a healthy deer herd that boast some big ole whitetail bucks.

Prescribed fire is an effective management tool for deer throughout the white-tailed deer’s range because most native brush species respond well by root-sprouting, regrowing, and providing high-protein browse. You see, most plant species are well-adapted to fire, but all deer managers that use fire as a management tool prefer prescribed or controlled burning. The fire that swept across the Chaparral WMA, on the other hand, was a wildfire. And although wildfires and prescribed fires ultimately have the same impact on native plants, prescribed fires are planned and allow burners the most preparation. Prescribed fires allow landowners the ability to pre-select the areas to be burned and the conditions under which they are burned.

For those interested in using fire as a management tool, it’s recommended that no more than 20% of a property be burned annually. This keeps different successional stages of plants located throughout the property and provides deer with optimal forage. I mentioned earlier that the wildfire that crossed the Chaparral burned 95% of the research WMA. Keep in mind that the perimeter of the area is game-fenced and very few deer were found dead post-fire, so that left all the deer found on the 15,000 acre property about 700 non-burned acres to forage. But white-tailed deer are resilient animals.

Chaparral WMA staff and researchers from Texas A&M University-Kingsville used the effects of the wildfire to monitor how deer living on the area would respond. What would deer eat in the short-term? Would there be enough food to maintain body condition and support fawning? That was just a few of the questions managers needed to answer to determine if the deer herd could respond the the widespread setback in habitat.

It’s important to note that the month of March is smack-dab in the middle of a white-tailed does’ pregnancy. And pregnancy requires a high amount of dietary input. Researchers collected does at two week intervals from mid-April to mid-June and recorded live weight, body condition, rumen contents, and the number and size of fetuses. A total of 28 does were collected and 23 pregnant does carried 6 single fawns, 16 twins, and 1 set of triplets. Shortly after the fire, rumen contents consisted primarily (90%) of cactus and grasses. However, deer shifted to forbs and mast (fruits) as these foods became available after the fire.

Data collected on the Chaparral WMA found that deer were able to maintain body condition and pregnancy after a large-scale fire. However, the management area did have a lot of things going for it that may or may not be available in some areas. First, the deer herd was below the carrying capacity of the land prior to the fire. In addition, the area was fortunate to have an abundance of cactus that provided a moisture-rich post-fire food for white-tailed deer. Although deer were able to switch their diets in order to survive, would this be the case in your area after a wildfire?

Fire is one of the most beneficial tools in wildlife management because when used properly it is very economical. In addition, fire releases nutrients that are bound in dead organic material, fire stimulates the germination of certain plant species, and fire controls plants such as blueberry cedar that are not fire adapted. And although we have learned that whitetail can cope with large-scale fire in South Texas, I do not recommend burning more than 20% of your property on an annual basis. Just keep in mind that with burning 90% of the work takes place before you strike the first match.

Deer Not Eating Protein Pellets?

Genetics (genes) are the most important factor in determining antler characteristics in whitetail bucks. However, genes are not the only factors that determines a buck’s antler potential. Both age and nutritioninfluence how a deer’s genes are expressed. For example, even a buck with the genetic composition to grow the largest rack in the world was harvested at a young age or was malnourished, then the genes that the buck carried were never fully observed. Because age and nutrition determine how a buck’s genes are expressed, these factors are critical to the success of a sound deer management program that strives to produce high-quality bucks.

Although proper buck harvest is necessary to promote age and antler characteristics, nutrition can be achieved through a combination of habitat management and supplemental feeding. Habitat management is the single best way to provide year-round, high-quality food for deer, but this is typically only a viable option for land owners. Habitat management is not always feasible for hunters that lease land for deer hunting for a variety of reasons. In this case, hunters are limited to providing supplemental food through either food plots or free-choice protein pellets. Continue reading “Deer Not Eating Protein Pellets?”

Winter Deer Browse Gets More Important as Temps Fall

White-tailed deer are primarily browsers. They typically eat very little grass, with most studies estimating grass comprising no more than 7 to 9% of a deer’s diet in any season. Browse consumption is important to deer, but learning to read browse utilization can be important to your overall deer management program. Browse is defined as the leaves, twigs, and buds of woody plants. Browse is the bread and butter of a white-tailed deer’s diet on almost every landscape, but the importance of browse becomes particularly important during the winter months.

Why? Well, winter is the most nutritionally stressful time of the year for deer. Not only does a deer require massive amounts of energy to regulate its body temperature during the coldest part of the year, but food in many cases is not readily available. This is especially true at northern latitudes where extreme winter conditions prevail. In the southern part of the white-tailed deer’s range, winter temperatures are simply mild inconveniences. However, prolonged periods of cold weather at southern latitudes can take its toll on deer populations in this area simply because deer densities are higher. There may be more browse in southern forests, but there are also more deer! Continue reading “Winter Deer Browse Gets More Important as Temps Fall”

Food Habits of White-tailed Deer in Texas

Landowners, deer hunters, and deer managers and biologists have long recognized the need for a comprehensive study on food habits and the seasonal preference of plants eaten by white-tailed deer in Texas. Knowledge about the food habits of deer is fundamental to deer habitat management and wildlife managers for a better understanding of the food requirements important to whitetail and other wildlife species.

Food habit studies conducted in other parts of the U.S. do not represent the seasonal availability or preference for plants used by white-tailed deer in the north central portion of Texas.

In the mid-1990s, a research study was initiated by the Texas Parks and Wildlife Department to address these deer-related questions. Prior to this work, no definitive research had been conducted in north-central Texas. The purposes of the study were to identify what plants are seasonally important in the diets of white-tailed deer and which plants they prefer with regard to seasonal availability.

In addition, foods represented in deer diets could be grouped into general forage classes (grasses, forbs, browse, mast) by season to provide land managers information for conservation and management of key habitat components for white-tailed deer.

White-tailed Deer Diet in Texas

To accomplish this task, whitetail were collected from private ranches in six counties located throughout the area. This counties included Bosque, Brown, Erath, Jack, Parker, and Wise. Collection sites were grouped specifically to represent the two major soil and geologic regions containing sandstone and limestone based soil groups and associated plant communities and habitat. As you would expect, a wide variety of habitat types and land management operations occurred on these properties.

The properties included high and low fences, different livestock densities and grazing systems, poor to excellent range conditions, the presence of absence of agricultural crops, supplemental feeding programs, and varying densities of white-tailed deer. The study differed from many previous works describing deer foods in that data was collected over a broad geographic area and wide variation of land uses.

Deer diets and available food sources were studied year-round for two consecutive years. Deer diets were described by examining stomach contents from deer collected across each of the ranches where samples were collected. Available food sources of food were described by conducting vegetation surveys. A plant list was developed of all plant species identified on each of the sites. A minimum of 5 white-tailed deer, primarily does, were collected during feeding hours following sundown on each site for two years during the months of May, August, November, and February. Over 230 deer were collected!

What do Deer in Texas Eat?

A sample of rumen contents for each deer was collected and washed to address deer food habits. Plant fragments were studied and identified to genus or species where possible by general leaf shape and other external characteristics. Identification of fragments was based on a plant reference slide collection prepared at the beginning of the study for each site.

Identification of browse — tender growth and leaves of woody plants — and forbs was based on epidermal and morphological characteristics of leaves and stems. Forbs, by the way, are broad-leafed weeds. Monocots, commonly referred to as grasses, were identified by the size, shape, absence or presence of hairs and specialized epidermal cells. Keep reading to find out more about the food preferences of white-tailed deer.