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| WHITETAIL DEER - THE SPECIES
Whitetails (Odocoileus virginiansis ) have been around a long time. The species is 3½ million years old, and they are such awesomely successful survivors that they have not changed over these millions of years. They did not change because they are so well designed they did not need to. While whitetail ancesters are not as ancient as the ancestors of other deer ( Muntjac ancestors arose in the middle of the Miocene Epoch [22--42 million years ago], while the whitetail ancestors came along in the late Pleiocene [3.4--5.2 million years ago] .) But whitetails are the oldest living deer species. The strength of the whitetail is its flexibility; they are ecological generalists, or opportunists. This means that, as a group, they can get by in all sorts of environments, different climates and temperatures; they can eat a huge variety of foods...they have been documented eating fish, dead birds and insects! Their flexibility allows them to coexist with human development; they are frequenters of farm crops and back yards, and can also be serious pests, not only agriculturally, but on the road causing car accidents and human deaths as well. There are 37 subspecies of whitetail in North and South America (This does not include the mule deer and blacktailed deer which belong to a separate species), but DNA testing is showing that many of the deer now listed as subspecies are actually just locally adapted versions of the near-perfect original. WHITETAIL HABITAT Whitetail like to live in the woods, dry or swampy, and the borders of woods. And whitetail love water. They are excellent swimmers, and will swim safely out to sea to a distance of five miles! The typical whitetail, restricted to open grass plains, would not survive. Although, to everything there are exceptions, and whitetails for example who are facing deep, obstructing snow that slows their escape, or even traps them in place, will then yard on flat, windblown prairies. They are choosing the less dangerous of two very dangerous options. Their normal way of escaping predators cannot be used in open country. When yarded up in winter the herd is preyed upon by predators, and it is mostly the young, the old and the sick on the outer edges that are the ones attacked. Hoofed animals that live out in the open, such as elk, are usually distance runners, and if they can run faster than their predators and outlast their predators, who for the most part are also good runners, they get to live another day. A whitetail in the open though is a sitting duck for a pack of wolves, coyotes or dogs who are committed to the chase. As a group, whitetails are hiders, dodgers and sprinters, not distance runners, who like to out run and put obstacles between themselves and the predator. The whitetail deer's first concern is safety, so their environment must have what they need to allow them to maximize their best protection strategies. The doe with fawns is more intensely safety conscious than the buck, and a buck in rut can actually get quite stupid and forgo safety for the chance to breed. But, if the food is great, but safety is not, deer generally will shun that location in favor of a more secure place. Individual whitetails are extremely loyal to their own territory, although they will leave it for up to several days if they are being hunted there, and they will leave it permanently if it becomes unsafe. In these cases their loyalty to their deeply ingrained anti-predator instincts win out over their attachment to the home territory. However, there are stories of whitetails that have starved rather than leave a barren home territory, in this case their attachment to their home keeps them on a doomed path to starvation. If their habitat is invaded by competitors, like exotic deer, the whitetails compete poorly. Whitetail deer in Maryland were being pushed out by the oriental sika deer until conservation management helped them out. Overall, a specialist will out compete a generalist in an established area, but while the specialist may win the battle, the flexibility of the generalist, over the long run, lets them win the war. WHITETAIL DIET The whitetail dietary flexibility stops at grass. They did not develop into grazers like some of the other deer species. They did not develop the special teeth or stomachs that can efficiently grind up and digest the tough fibers in grasses (like the horses and bovines did for example). The types of deer that do graze (like the axis deer) prefer to follow behind the coarse grass grazers so they can eat the new-sprouting, more tender shoots that spring up after the first "mowing". Whitetail, like all deer, have incisor teeth (the cutting teeth in front) on only the bottom jaw, and a cartilage pad on the front of the upper jaw (They have molars on both upper and lower jaws.) This tooth pattern causes them to pull out the grass rather than to cut it like the specialized grazers do. The tender base of the grass is low in fiber, more nutritious and more digestible. So while whitetail can digest some of the grasses' most tender shoots, overall they would not thrive on grass alone. What they eat is a huge variety of low fiber foods, they are "concentrate selectors". They eat tender shoots and leaves from all sorts of trees, vines, plants and bushes; fruits, vegetables, nuts (acorns are a real favorite), grains, mushrooms (a gourmet treat to deer) and mosses. Here in the South they eat Spanish moss (which is actually a bromeliad) and up in the cold climates in winter they eat frozen vegetation that has turned into a nutritious natural silage. Many of the foods, even the good ones, that deer eat have poison in them, for example, tannin in acorns and oaks. But the foods are eaten in small amounts or are eaten when the plants are young so that they have a lower amount of toxins, and in some cases the toxins are balanced and neutralized by other vegetation so that they are not harmful. When tender shoots mature, they become tougher, have more fiber, have less nutrition and are more toxic, this is how the plants protect themselves, and how they discourage animals from eating them. The deer's diet can turn into a starvation diet if food runs out in winter, and deer will then eat the undesirable mature forms of the previously delectable foods, and in fact will eat almost anything. At times a starving deer will have a belly filled with food that it cannot digest and will die with a full stomach. WHITETAIL DIGESTION When deer eat they are feeding themselves, but they are also feeding their gut microorganisms. Deer digestion is 100% dependent on them. They help break down the food, and without them the deer cannot digest. Deer are ruminants, meaning that they bring their food back up to chew it again. If a deer, or any ruminant, starves to the point of also starving off the good microorganisms, in order to survive, the deer will need to get not just food, but needs to get replacement gut flora too. Even with all the food a deer could want, it would starve to death if the gut flora is not replaced. For their special type of digestion deer have stomachs with four sections, all in a row. The first section, the rumen, is where the food goes first after it has been chewed and swallowed. It can hold over two gallons, and this lets the deer bolt down a large amount of food if necessary so that it can quickly leave an area to return to safety. It is in the rumen that food is held to be brought up into its mouth later for rechewing, this is rumination or "chewing its cud". The food is then ready to go to the second section of stomach, the reticulum. The real digestion takes place in the third section, the omasum. The last section of stomach is called the abomasum, and here the food is pelleted and routed for exit. WHITETAIL SURVIVAL Whitetail deer are great escape artists, and that is another key to their successful strategy for survival. Their style of escape is a high speed sprint which puts obstacles between themselves and their pursuer. They can also play cagey tricks: they might hide and remain hidden until the predator is very near, and then make an explosive escape...they're gone down a well known escape route before the confused predator knows it. They will cross their own path, sometimes circling and crossing many times, to make their trail confusing. They will slink away on their bellies. They will walk in water to delete their trail, and will even hide by submerging themselves in the water, using their noses like snorkels. They are also known to run near other deer trying to shuck off the predator onto another unlucky animal. Typically though they escape down a well known trail with twists and turns that the trailing predator has to figure out at every change. The path might have obstacles that the fleeing deer knows it can easily and expertly clear, while the pursuer has to figure them out, then wear itself out climbing, jumping, detouring or tunneling, all the while trying to keep track of its prey. Whitetail in a new, unknown territory are much more likely to be killed by predators. Whitetail fawns start to practice their acrobatic survival skills when they are only days old. They will use their flimsy looking fawn legs to suddenly jump straight up in the air, maybe twisting in the air and landing at an angle, then lowering their heads like they have horns and are challenging an opponent...then it might be over, or the fawn might pop around escaping an imaginary predator for quite a while. Then the time comes, and it doesn't take long, when the young fawn discovers speed...it will sprint, flat-out, close to the ground, suddenly change direction and run some more. If there are no playmates to frolic along it doesn't stop the fawn, it will sharpen its life-saving skills by itself. WHITETAIL RANGE The whitetail's range is limited to North and South America. It extends from Canada, near the Arctic Circle, to Peru and Brazil in South America. The whitetail's range covers more latitude than any other ungulate (hoofed animal) in the world. Our North American whitetail have been successfully transplanted as exotics to Finland (which proves that they really are a cold-adapted deer), but have failed when they were introduced everywhere else. That is because they just cannot successfully compete head to head with specialists who are well adapted and on their own turf. While whitetail deer are premier survivors : shakeup the environment, whether by fire, earthquake, volcano, avalanche, Ice Age extinctions, urban development or whatever other disaster you can imagine, and the whitetail will out-survive their competitors whose special needs are less likely to be met in a state of natural chaos or, if you prefer, natural renewal. The whitetail thrive on the tender new shoots that follow the clearing off of a mature habitat. They moved into the ranges that were left empty by the large North American animals after they had become extinct during the Ice Ages. Some, but not all, scientists believe that all of the living species of deer in South America branched off in the past from the whitetail. WHITETAIL BREEDING In climates with cold seasons, whitetail deer follow a well timed rutting period. The colder the climate, the more rigidly set is the season of abundance, and timing is critical if the animals and their young are going to get the nourishment they need when they need it most. In tropical climates breeding is more laid back, and whitetail can even breed year round. In cold climates, however, a doe that produces late fawns is more likely to face winter with her fawns still too young, so that they cannot survive the starvation and stress of winter. At the same time she has been run down by nursing and has not had time to fatten herself up so that she can hold up to the winter. A doe that has a too-early fawn risks the chance that springtime will not be there yet when she desperately needs quality food to nourish herself and produce rich milk for her fawn. Nature strictly culls the cold weather animals that do not follow the calendar. COURTSHIP Does choose the buck they will breed with. Until they are fully in season they run off from the pursuing males. When ready, they will stand for the buck of their choice to be mounted. Does look for a successful potential father because that means that their fawns will carry the genes that will give them the best chances of being healthy and smart, and of surviving and reproducing. A desirable buck is a capable buck. He is healthy to start with, then he shows his intelligence and skill by managing to get maximum nourishment. He will show it in his large body size, his prime condition and strength, and in his large antlers. ANTLERS Antlers are made of true bone that is fed by blood carried by the outer velvet covering. Velvet antlers are hot to the touch, with brushy hair and a waxy-feeling coating. Deer need both protein and minerals to grow them. This is in contrast to horned animals whose horns are made of keratin (like fingernails), who do not shed, and who need only protein to grow their horns optimally. Appreciate too that whitetails must grow a new set of antlers every year, while animals who have horns only need to add gradually to their existing horns. A buck in velvet is sensitive and extremely protective of his antlers. These bucks will not fight or spar with their antlers, and if provoked will rise to strike with their just as deadly hooves instead. Watching a buck in velvet slipping through the woods, you will see him delicately turn to avoid brushing the branches with his antlers. A buck that is in hard horn knows it, and it makes him cocky. If a buck in hard horn sees a more dominant buck who has already shed his antlers, has broken his antlers or who is still in velvet, the "fully armed" buck can take advantage and play the bully. The whitetail's antlers though are not just for defense. The antlers are used for two other important purposes, both related to reproduction. One purpose is to advertise to females their good health, mature age and fitness as a mate. The other purpose is to use them as a grappling tool to engage in a test of breeding fitness against other bucks. Male rank is not usually determined by all out fighting. The bucks mainly spar to see who is the stronger contender, but they can also spar in a friendly way, for practice, even with a smaller buck, or a young one, and if the large buck's rack is too large, he might offer the young buck just one of his antlers to lock onto. In the common sparring match, the bucks lock their antlers, twist their necks and push in circles, with each deer trying to throw the other off balance. This will show both bucks who is the fittest. A head-on death match can sometimes occur between two steamed up, equally matched opponents. Obviously though, if that was the usual way, the damage that they did to each other would not allow for much breeding because the bucks would be dead, dying or severely injured. As it is, bucks suffer many injuries in the normal, "gentler" sparring contests of a breeding season, and that is in addition to the other severe stresses they endure in the breeding season. After rubbing off their velvet, over one day or a few days, bucks start to rub and play fight with trees and brush. A buck can sometimes hang from a tree by his antlers if they get locked in the branches, but the boisterous buck in the end does manage to wriggle loose. You can easily spot the buck rubs...they are usually saplings with the bark rubbed off. If you see a sapling scraped to a height of eight or ten feet, don't assume that it was made by a giant deer...the long scar comes about by the buck bending the tree to the ground as he continues to rub. It is less common to see a deer rub on a thick, unbending tree. It is now that the rutting bucks also begin to make their scrapes. FAWNS Does can give birth to from one to three fawns, uncommonly four, and, this is hearsay, but five are said to have been born to a single doe. Usually the does have two fawns. In keeping with their flexibility as survivors, whitetails have a "strategy" for good years and bad years. In the poorest years a doe might not breed at all; in a bad year she will have a single, and in a normal year she will usually produce twins. If, in a good year she used her energy surplus to just make a bigger fawn, she would probably have trouble giving birth to it. If, in a bad year she tried to grow twins, the twins would be malnourished in the uterus, the pregnant doe would be starved and weakened so she would be more likely to be taken down by predators, or to get sick. If the doe and her fawns somehow made it to a successful birth, the doe would not be able to produce enough milk for the normal growth of her two fawns, and the fawns' odds of survival in those dangerous first days of life would be worse than normal...and normal is very high risk. Sometime before delivering her new fawns, the mother doe will drive off last year's male offspring. Male deer have no inhibitions about trying to breed their own mother. She will however tolerate her female offspring, and whitetail often form maternal family groups. The actual birth can take minutes to hours. It is touching and almost painful to watch new fawns, struggling to manage their long, stick like legs, some of them collapsing repeatedly, resting between efforts. At this stage right after birth, the fawn does not know that it is a deer, and might follow, anyone. The mother doe, in these first "getting to know you" days, has to sometimes claim back a fawn that goes to another doe, ready to follow her as its mother. Sometimes a fawn that tries to call another doe "mom" will be bluntly run off. Sometimes a doe will obligingly accept another's fawn that wants to nurse. The mother cleans, inspects, and then leads her fawns from the birthing area to hide them while she returns to eat the placenta. She does this to remove the scent of blood, so they will all remain as invisible to predators as possible. The placenta is most likely a source of quality nourishment as well for the doe that must now go on to produce the rich deer milk. The hiding fawns are helped by their lack of body scent for the first few days. When in a few hours the fawns are more oriented, they will hide with a vengeance. If they sense any movement at all they might drop to their bellies like a trained soldier; sometimes they just collapse like a pile of sticks and will not move from even the most awkward position. If they are old enough to be curled up in the typical "cute fawn" position, they will hold as still as the earth, keeping their heads up and alert or tucked down if that was their posture when they spotted trouble. Some might bolt at a thing's approach, but others, usually those who are only hours to a few days old, will hold tight even as a mowing machine comes down on top of them. An amazing example of the resourcefulness of a fawn was displayed when I had to retrieve twin fawns whose mother had died from mastitis. I found one twin, but couldn't find the other. I walked the pen, which had foot high grass, over and over. I checked the fence closely to see if he could have escaped. Nothing. Finally, in my continued search, I caught something out of the corner of my eye. It was the three day old fawn carefully slipping along the fence. He had been moving from spot to spot to elude me, so that I was always looking where he wasn't! Does and fawns do not instantly bond. The bond gradually builds by suckling and mutual grooming. The doe stimulates and consumes the urine and feces of the fawn, again to eliminate scent, and again probably as a source of nourishment. A doe will sometimes protect her fawn if the predator is small, but more often she will not. Many fawns are lost to predators and does often must stoically move on without the fawns they produced, this breeding season a loss. The mother-fawn bond can also be broken in cases of starvation in which a doe will drive her own fawn away from a food source. That is nature's strict law for the species: the fittest come first. A doe can make more fawns, but she must be fed, alive and healthy to do it. TAME WHITETAIL Whitetails are exquisite in their grace and beauty, and under special conditions, where their nature and needs are understood, they can be tamed and kept as pets. It is definitely not a commitment to be taken lightly though. Whitetail deer live 20 years or more in captivity, and have many special needs...not only to be comfortable, but to simply survive. It is important to realize that deer are prey animals, while dogs and cats for example are predators. Deer are more like birds and horses who make their way in the world by being constantly alert and ready to take flight at the least whiff of danger. A prey animal will only turn to fight a predator as a last and most unwelcome choice. The prey animals that live the longest are the ones with the keenest senses, reflexes, wariness, brains and physical fitness. Its flight response though is what powers the frightened deer that will, in blind terror, hurl itself into a solid object, off a precipice, into fencing or other damaging situation, and kill or injure itself. A pet deer will, bit by bit, relinquish its profoundly wild instincts as it is tamed. An animal that is imprinted (using the word loosely) on humans will allow a person into its most intimate, personal space, and will allow very familiar physical contact. An animal that is merely hand-tame will allow closeness usually only to accept food or limited petting, and it would bolt off in a panic if you, for example, tried to hug it. Many wild animals' personal spaces shrink with familiarity. They might know that a particular dog never behaves in a predatory way, and so pay little attention to it, even allowing it into it's familiar personal space. A tolerant, pen raised deer might accept a distance of, say, 20 feet between itself and its caretaker, but have a stranger come along with the caretaker and the deer will blast off in a panic. Or, if the familiar person tries to close that 20 feet to 15 feet, the deer's flight response will kick in with full force. Finally, a completely wild animal will have its natural, unadulterated "flight distance". Just as humans have their own personal space that, if intruded upon, will make them feel crowded and alarmed, other species as well have their own typical distance that, if trespassed upon, will trigger flight. For the whitetail this distance is 200 feet, while for the pronghorn for example it is 500 feet. Tame bucks though, because they are tame, can be killers. In the wild a buck has an intense need to preserve its own flight distance, and would not think of coming close to a human, and that is exactly what protects us. Once that need for distance is gone, the aggressive, rutting buck (even more so if a person happens to come between the buck and a doe he is courting) has no sense of needing to preserve its space, and that is when he becomes seriously dangerous. I finally had to bully the poor buck with the tractor bucket...for quite a while...before he would concede the match and back off. If a fawn is picked up the wrong way, it will use it's pointed hooves, and twiggy little legs to connect with a power that would shock you...it will shred your clothing and cover you with welts, lacerations and bruises. Compare that to the large, thickly muscled hindquarters of an adult buck that he uses to drive forward his multiply pointed weapon. Keep in mind that a buck in rut, or to be safe ANY buck in hard horn is a crazed, hormone driven breeding machine. A large number of people are killed by their trusted tame deer each year because they do not understand the extremes in the nature of the normal breeding buck. WHITETAIL, MULE DEER AND BLACKTAIL...WHAT'S THE DIFFERENCE? Whitetail are the oldest living species of deer at 3.5 million years old. The blacktail deer split off from the whitetail at some time in the past, thought to be a million years ago or more. The blacktail are a different species from the whitetail. The blacktail deer then split off a subspecies, the mule deer ( Odocoileus hemionus hemionus ), which is the youngest living deer species, arising 10,000 years ago. So the blacktail and mule deer are the same species, but the mulie is a subspecies of the blacktail, and they are both close cousins to the whitetail. Of course nothing is ever simple, and there is a three way relationship, complicated by DNA evidence that the making of the mule deer involved some crossing back of the whitetail to the blacktail deer. The two species do not normally interbreed in a natural setting, but will if kept confined together. The hybrids do well in captivity, but in the wild they rarely survive because they do not know how to follow the successful survival strategies of either parent, and so are vulnerable to predators. Blacktails range from Alaska and British Columbia in the north with the sitka deer and Colombian blacktail deer, down through the California mule deer, the inyo deer in the Sierras, the Rocky Mountain mule deer, to the burro (bura) deer of the southwestern deserts and Mexico. The ranges of the subspecies of blacktail overlap latitudes, but the blacktail deer exist no farther east than the Rocky Mountains. There are some other named subspecies of blacktail, but there is debate as to their validity. An essential divide between the whitetail and blacktail species is their different choices of terrain and their different escape strategies. The mule deer lives in rough but open country and uses a special kind of pogo stick jumping as its main escape from predators. It is called "stotting". A single, springing jump can cover more than twenty-five feet! The mule deer will tend to pogo itself uphill when it escapes. This is a very different strategy from the whitetail who sprints, running downhill, using gravity to increase its speed, thus often running to water. The whitetail hides, jumps only over obstacles, and prefers the cover of its well known home range in the woods, and prefers the terrain to be even so it will not slow down its sprint to safety. When a mule deer stotts it is choosing a slower escape than if it galloped away. The jumping works better though for a few reasons: One is that the high jumping mulie can go uphill and it does not cost him much more energy than jumping on level ground. For the earth bound predator though, climbing uphill increases its energy output enormously. Another advantage is that the mule deer's territory is usually rough and uneven and it can match its jumps to the uneven terrain, sailing over obstacles that slow down the predator who has to climb over, under or around, and sailing over gaps that the predator cannot cross at all. A final advantage is the unpredictable direction of the jumps. Some people say that it seems like the deer itself doesn't know which direction it will bounce off to next, and this leaves the predator swirling in confusion, either unable to anticipate where to attack, or wasting huge amounts of energy on attacks into thin air. Why don't you ever hear about mule deer here in the South? There is a disease barrier between the climates that have killing frosts that eliminate certain parasites and disease carrying insects, and the year round milder climate of the South that does not. To put it simply, you do not see mule deer in the South, or for that matter moose, because we cannot keep them alive and healthy due to disease. THE FUTURE OF THE WHITETAIL Whitetail deer are not endangered now, but, like many of our other animals in the Americas, had been in the past. They were reduced to critically low numbers, not however due to habitat loss (the cause that we most often hear relating to endangered species). Because the whitetail is the millions-of-years-old, ubiquitous generalist that can survive in hundreds of different habitats, they were unaffected, and probably even benefited from the expansion of the human population. The whitetail's decimation was due to over hunting. Happily, through conservation efforts, whitetails have been brought back to plentiful, and even excessive numbers. The whitetail populations tend to expand explosively because their historic predators, the large carnivores, are not available to do the culling, and because agriculture provides them with access to unprecedented amounts of high quality feed. Whitetail deer are the focus of ongoing research directed toward informed, effective management of their population size and health, with special concerns for producing mature, healthy trophy bucks, and preventing overpopulation that dooms the animals to illness, starvation and desperate winter deaths. The whitetail's future is secure, but it is up to us to optimize it. |