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Life & Times of the Whitetail

Bubba Was Here

By J.T. Fleegle
Wildlife Biologist

He's of prime age and is available. He hangs with the bucks in the Yoak gang, but he is not the biggest or the baddest. He passed by on Tues. at 3 o'clock.

This is a lot to communicate, but deer can get this information from a quick whiff at any signpost. Bucks place signposts— licking branches, rubs and scrapes—yearround throughout their territory. Because bucks and does travel in different social circles, signposts facilitate communications for both sexes.

In the spring and summer, when tender new antlers are developing under a cushion of velvet, bucks communicate through the communal licking of branches. These branches usually are located over a trail or along the edge of a field, just above normal deer height. By mouthing the branch and sometimes rubbing it with their forehead or preorbital glands, bucks smell and taste "notes" left by other deer. Identities, status and social bonding can all be gathered through the nose. During summer, the licking branches are used by all bucks in the area, dominant or not; a one-stop gossip rag for all the deer in the neighborhood.

After their headgear has hardened and the velvet begins to shed, bucks begin tearing and rubbing the bark off bushes and trees with their antlers. Rubbing during and shortly after velvet loss is violent, as bucks thrash bushes to get a feel for what has been growing on their heads all summer. As the rut progresses, rubbing evolves into the more typical, highly visual buck rub. Once the rub is complete, bucks anoint it with their forehead gland. Some rubs are used year after year. Age plays a factor in rub making. Yearlings typically rub saplings no more than two to three inches in diameter, while a mature buck may rub trees six inches or larger. This work doesn't go unnoticed, as bucks and does visit rubs.

The most complex signpost bucks use is a scrape. It is used most intensely just before the peak of the rut. A full scrape involves branch marking, pawing and urination. A scrape starts with an overhanging limb on which a buck will rub his forehead or preorbital gland. If the mood strikes him, he'll even rattle the branch with his antlers. He takes the twig in his mouth and moistens it, thereby leaving his mark and detecting the mark of others using the scrape. Then he clears a 3- to 6-foot circle by pawing the ground, steps into the circle and urinates onto his tarsal glands while rubbing them together. Usually, only mature dominant bucks produce a significant number of scrapes. So while the whitetail spends its days in relative silence, plenty is being said. You just have to look, lick or smell.

Is there a doctor in the house?

By J.T. Fleegle
Wildlife Biologist

Viruses, bacteria, and parasite— each can cause illness or even death to a white-tailed deer. Entire books are written on the topic. But there are no doctors in the forest. Luckily, 99 percent of the time, deer are healthy. Usually, only when deer are stressed and their immune systems are compromised do they become susceptible to an endless list of unpronounceable pathogens.

Hemorrhagic disease is caused by the epizootic hemorrhagic disease and bluetongue viruses. The first documented outbreak was in 1955 in New Jersey. In its acute form, it causes sudden loss of appetite, disorientation, weakness, respiratory distress and rapid death. Die-offs occur suddenly and almost exclusively in late summer and early fall and coincide with peak populations of insects called midges or "nosee- ums," which transmit the disease. It is common in southeastern states though outbreaks have been documented outside of this range including in Pennsylvania. Many infected deer live and show only mild signs of disease or no signs at all. Even if a forest emergency room existed, this deer disease is untreatable.

Another virus causes cutaneous fibromas— hairless tumors found on the skin. They can be found on any part of the deer's skin and vary in size from ¼-inch to more than 8 inches in diameter. Most fibromas are black or gray in color, and they can be smooth or warty. Deer with cutaneous fibromas won't win any beauty contests, but the growths are often temporary and usually harmless.

Bacteria don't get as many headlines as viruses. Anthrax is an often-fatal disease caused by the anthrax bacterium, which can remain in the soil for years. While this is a frightening thought, only a few outbreaks have been reported. Brain abscesses are also the result of bacteria. A number of bacteria can be responsible for infections that cause neurological problems like circling, lack of coordination and other abnormal behaviors. Sparring and rubbing puts bucks at a higher risk of developing brain abscesses than does.

As for hitchhiking parasites, liver flukes, nasal bots, louse flies, a variety of worms, and more than 20 species of ticks can call a deer home. Deer tolerate them all without much fuss.

Habitat, Sweet Habitat

By J.T. Fleegle
Wildlife Biologist

If there's one thing everybody needs, it's a place to call home —a place to find shelter, a good meal, a drink of water and a warm bed. For deer and other wildlife, that home is called habitat. Any place that provides food, water, bedding areas, fawning areas and escape cover can be deer habitat. Deer are very adaptable. There are few places that a deer cannot find the things it needs to survive, which means they can be found from the big woods to Lancaster farms to Pittsburgh suburbs. Though deer can live almost anywhere, all habitats are not created equal.

In "good" habitat, food and cover sources are plentiful and of high quality, resulting in less time and travel to find them. The body condition of deer in good habitat is better because they expend little energy for the essentials of life, and they are more productive. Deer in poor quality habitats spend more time and energy finding food and or cover.

What does good and poor habitat look like? Take a walk outside, what do you see? Would a deer have a place to hide or something to eat? What is growing within a deer's reach— below a height of five feet? Just because it's green and grows, doesn't mean it's deer food. Hay-scented fern, for example, covers vast expanses of the forest floor but deer avoid browsing it because it contains an enzyme that inhibits a deer's ability to absorb nutrition.

Deer need to consume four to eight pounds of forage (thousands of calories) a day for body maintenance, growth and activity. The bigger the deer, the more food it needs. During winter, the maintenance energy for a 120-pound deer is more than 3,100 calories per day. Add the energy needed for travel, feeding, and, for females, fetus growth, and that number jumps to more than 18,000 calories per day.

Nutritional quality varies among food sources. Consider some of a deer's winter forage: hemlock has about 2,300 calories per pound; hobblebush twigs, 2,100; maple twigs, 2,100; cedar, 1,050; pine and twigs, 1,100; and aspen, 1,150. If it's a good year for acorns, the supply can last well into winter and they have about 2,300 calories per pound. Not all forage below five feet is our equivalent of filet mignon

Bobcats & Coyotes & Bears, Oh My!

By J.T. Fleegle
Wildlife Biologist

Dorothy isn't the only one afraid of getting eaten by a bear. For a prey species, danger could be lurking around every corner. Deer have been meals for mountain lions, wolves, coyotes, bears, lynx, bobcats, eagles and even alligators. Through it all, deer have persevered in this evolutionary cat-and-mouse game. In Pennsylvania today, the deer's list of enemies is shorter than it once was, but still includes bobcats, coyotes, black bears, and, of course, humans!

Historically, mountain lions, wolves and people were the main predators of whitetailed deer. Mountain lions are solitary predators that stalk their prey. In western states, 60 to 80 percent of their diet is deer. Wolves chase their prey in packs and travel extensively to find their quarry. The staple of their diet throughout their North American range is white-tailed deer. An adult wolf can consume 20 or more deer annually, half of which may be fawns. A recent Pennsylvania study investigating fawn survival showed 46 percent of mortalities were the result of a predator — 1/3 from coyotes, 1/3 from black bears, and 1/3 unknown. Bob cats killed only a few fawns. Pennsylvania research has documented only three coyote kills, one black bear kill, and one bobcat kill out of hundreds of adult deer collared.

Deer are not completely defenseless against attacks. Evolving with mountain lions and wolves has given them some pointers. Deer are most vulnerable at birth. In a strategy called predator swamping most fawns are born in a 2-week period, swamping the market with more fawns than predators can eat. And when fawns remain motionless (another survival strategy), their speckled coat and lack of odor help them escape detection. As fawns age, they get stronger. In three days, a fawn can outrun a human; in three weeks, a coyote; and in six weeks, a bobcat. When they reach adulthood, alertness and speed are a deer's greatest defenses. Hearing, sight, and smell have become fine-tuned instruments, multiplied by 5, 10 or 20 herd members, a predator's meal becomes a tall order.

While bobcats, coyotes and bears are a fact of life for every deer, they have played the game before and victory is experienced with every escape.

Congratulations, it's a deer!

By J.T. Fleegle
Wildlife Biologist

May greets us with the return of many joyful visions: scarlet tanagers that set the treetops ablaze, daffodils swaying in the breeze, does lumbering along with bellies as big as barrels. Well, that last one may be a joyful sight to us, but the doe might have a different opinion. After a long winter and 200 days, she is about to grace the world with a new life, or two, or maybe three —it's fawning season

But these miracles will enter the world without baby showers, cigars or fanfare. In fact, it is just the opposite. Discretion and secrecy are top priority to any doe about to give birth. In preparation for the big event, a doe begins to avoid contact with members of her social group. If this is the first time she is giving birth, she will seek out a secluded birth site, usually outside of her core area. If she is an experienced mom, she will return to the same area every year to give birth. Labor lasts 12 or more hours. However, if disturbed, a deer may be able to stop the labor process —a definite plus for a prey species. After the little bundle(s) of joy arrive, mom licks them dry, nurses them and remains close-by for the first 24 hours. A doe and her fawns share a bond that helps her to distinguish them from all the other ungulate bundles of joy being born.

Whether a doe has one fawn or more depends on age and nutrition. Most yearling does, if they conceive at all, give birth to a single fawn. Twins are common among adult does. Deer herds in balance with the area's forage have the highest reproductive rates. Overstocked ranges produce few fawns. In Pennsylvania, 80 percent of yearling does that become pregnant produce single fawns, while 74 percent of does three years old or older produce twins, and only 3 percent of adult does produce triplets.

Like any mother, a doe gets better at parenting over time. Research has shown that fawns of experienced does (four years old or older) have lower mortality rates than those of younger does.

Older does are more dominant and can stake out better areas for fawn rearing. Single parenting is a full-time job for does. Between nursing, grooming and hiding her fawns, the summer flies by and her whitespotted baby is soon all grown up. But she has little time to reminisce, May will be here soon enough and another baby will be on the way

Gee, your hair looks terrific!

By J.T. Fleegle
Wildlife Biologist

What's so special about hair? When we look at a deer, hair is not the first thing we notice. All deer have hair, so, unless there is something unusual about it (like being white where it is normally brown), no one cares about deer hair. This unappreciated covering of the whitetail is, in fact, key to their survival. From the day a deer is born, its coat keeps it hidden from danger, warm through the winter, and cool during the summer. With a flash of the white hair on its tail, a deer can signal an entire herd that something is amiss.

Fawns are born with little strength and coordination. Their reddish-brown coat dappled with white spots disappears on the forest floor as just another pattern of sunlight and shadow, providing safety in plain sight. Before long the white spots of youth fade and gray shades of winter cloak every deer in the forest.

As the days grow shorter and the temperature begins to dip, this ghost of the forest continues its vanishing act. The hair of a deer's winter coat is mostly gray with reddish-brown tips, snow-white hair on the belly counteracts the shadow cast by the body and helps prevent a predator's eye from seeing a three-dimensional meal. As are most winter coats, a deer's is toasty warm. Underneath the guard hairs, a soft, wooly underfur is packed more densely than sheep's wool. Air is trapped in the underfur, warmed by the body, and held close to the skin. Bedded during a snow storm, a deer will quickly become a "snowdeer" as flakes pile up on its body instead of melting. Even deer that live in warmer climates need these insulating properties, because wet weather can be as bone chilling as cold weather. Luckily, their winter coats also are water-repellant, because of oils secreted by glands in the skin.

Just as we tuck our winter coats away as the weather warms, deer toss theirs to the ground. Large patches of gray guard hairs and soft underfur are replaced by reddishcolored guard hairs. During this transformation, deer have a "bad hair day" that may last several weeks. Without underfur, warm air is able to move away from the skin by convection, like built-in air conditioning.

So the next time you see a deer, be sure to notice what coat they're sporting and how very fashionable they truly are.

Did someone say FREE food?

By J.T. Fleegle
Wildlife Biologist

If you want to draw a crowd, offer free food. This works at church gatherings, open houses and booster meetings. It also works in backyards. In the case of deer, it can be harmful or, in fact, deadly. Decades of research show that supplemental feeding leads to increased disease risk, longterm habitat destruction, increased vehicle collisions, habituation to humans and alterations in deer behavior.

People often offer food to attract wildlife for viewing. Supplemental feeding congregates deer in unnatural densities. And, just like cramming 200 people on an airplane increases the odds of other passengers catching a case of the sniffles from seat 14B, gathering large numbers of deer in small areas increases the risk of spreading communicable diseases such as chronic wasting disease, tuberculosis and mange.

Deer can get sick merely by eating supplemental food. Rapid exposure to a concentrated grain diet, like corn, can cause a fatal disruption of the animal's rumen. By the time the microorganisms of the rumen adapt to a highly digestible, high energy, low fiber feed, the deer could be dead from a build up of lactic acid.

Deer behaving normally in winter eat less, move less, and rest in places protected from the weather in order to conserve energy and safeguard fat reserves. But, once a deer is a free-food junkie, it behaves unnaturally. Deer traveling to feeding locations leave protected areas and move farther than they otherwise would, only to reach feeding areas that are often open and exposed to harsh weather. Deer can burn more calories in travel and heat loss than they consume in feed. Traversing roads to reach feeding sites endangers motorists as well as deer, and deer using the sites lose their fear of humans, increasing the potential for aggressive behavior towards people.

Our human desire to reduce perceived suffering is noble, but nature has been coaching this game very successfully for millennia. Winter mortality will never be eliminated. While observing it is unpleasant, it is a natural part of living as a WILD animal. Rather than feeding, which contributes to habitat degradation by artificially supporting concentrated numbers of deer, we can help deer by improving habitat and natural food sources that benefit all wildlife. After all, there is no such thing as a free meal.

I'll just have a salad

By J.T. Fleegle
Wildlife Biologist

When you look at a menu, what's your favorite section? Pasta, appetizers, seafood, steak, salad? Well, if you were a deer, the salad section would top the list. Deer have adapted to obtain everything they need from vegetation. Deer are not alone in this endeavor. Other ruminants, like cows and sheep, make a living eating green stuff too. All share a very similar digestive system, including a 4-compartment stomach. The first compartment —the rumen—is the key to their vegetarian diet. The rumen is where fermentation (the breakdown of plant matter by enzymes produced by microorganisms) takes place, and it is the main difference between ruminants and people.

The slender, tapered muzzle of a deer allows it to be specific in foraging, selecting the best parts of the best plants. They seem to select foods with low cell-wall content and comparatively high protein-totannin ratio. This is notable because deer do not have or need the diversity of microorganisms in their rumen that grasschewing cows do. Thus, all rumens are not created equal and vegetation that sustains one species will not necessarily sustain another.

It takes two to four weeks for rumen microbes in deer to adjust to a new diet. This is not a problem because seasons change gradually and deer shift from goldenrod and clover in the spring; to mountain ash, cherry and bearberry in the summer; to acorns, apples and woody browse of red maple in the fall; to dead leaves, woody buds and conifers in the winter.

Abrupt changes in diet wreak havoc in the rumen. For example, deer adapted to a winter diet of woody vegetation will die of acidosis (a build up of lactic acid in the rumen) if they consume too much highquality grain such as corn.

For simple-stomached primates like ourselves, a rumen seems like way too much work for a bite to eat. But if you were looking at the menu and saw that YOU were on it, it might change your perspective. Being the preferred food item of other species, deer can't be lollygagging at dinner time. A deer only chews its food enough to swallow it. The rumen of a deer can hold 10 pounds or more, compared to a human stomach, which holds only a pound. This allows the deer to chow down a lot of food quickly, and then steal away to finish the digestive job in safety.

How old is that deer?

By J.T. Fleegle
Wildlife Biologist

This is a popular question around deer season. Often at processors and deer camps alike, you will hear phrases like, "Look at the rack, that buck must be four or five years old" or "That's an old deer, look at how gray she is in the muzzle." These observations, however, do not accurately reflect the age of a deer.

To accurately age a white-tailed deer, the best method is to pull a lower incisor, root attached, and send it to a laboratory for cross-sectioning. Many mammals, including deer, can be aged by staining teeth and counting the rings that appear, just like on a tree. This process of measuring a deer's age takes time and money; therefore, in most cases, estimating a deer's age is enough.

The age of white-tailed deer can be estimated by replacement patterns and tooth wear. Although antler size does increase with age, interactions between genetics and nutrition cause much variability in antler growth.

Up until about 10 months old, a deer has up to five teeth, premolars and molars, on each side of its lower jaw. Premolars are replaced as a deer reaches adulthood. Molars are permanent. Jaws with five or fewer teeth (three premolars and two molars) are those of fawns.

Around the time a deer becomes a year old its third and final molar emerges, creating a row of six teeth per side. At the same time, the premolars are replaced. During this period a deer is considered a yearling.

After it has its full complement of adult teeth, the age of a deer is estimated by tooth wear. As a deer gets older, its teeth wear down from grinding food. Though wear patterns are generally predictable, they are influenced by the type of food eaten, soil types, injury and individual chewing patterns. Thus, a deer's age cannot always be based on wear patterns alone.

For management purposes, the agency places deer into three age categories when collecting harvest data: 6 months (fawns), 18 months (yearlings), and 30-plus months (2½ years or older). Experienced deer agers may venture a guess beyond 2½ years but this is more of an art than a science.

The Birds & the Deer

By J.T. Fleegle
Wildlife Biologist

Where do baby deer come from? Bambi likely never asked his mother that question. Why? Because deer just know. Nature has programmed this species better than any computer technician ever could. The primary purpose of deer is to make sure there are more deer next year and the next year and the next. Individually, they are ensuring the survival of the species just by doing what they do.

Every fall there is a coordinated effort between does and bucks to ensure their genes will be passed on. Not because of the cooling temperatures or the colorful scenery. Because it is in their best interest to give birth during a time of year when weather and food conditions are favorable. Gestation in white-tailed deer is about 200 days. Hence, conception must take place in the fall for a spring birth to occur. This season of conception is more commonly known as the rut.

For bucks, the rut is very stressful. Bucks spend months preparing for the rut, starting in the spring with the growth of their antlers. Antlers are an important status symbol used to impress the does and intimidate other suitors. They are used to create rubs, which communicate with does and other bucks, and to spar with other bucks. As the rut draws near, lots of sparring and posturing occurs as bucks try to secure a higher rung on the dominance ladder.

But as the rut progresses, dominance means less because the majority of does come into estrous at the same time. In Pennsylvania, the first two weeks in November are the peak of the rut. That means hundreds of thousands of females are looking for a mate at the same time. The market is flooded for a short period because does are receptive for only 48 hours. No matter how old, how impressive a rack, or how dominant a buck, he can be in only one place at one time. Mating opportunities walk right by him when he is engaged in the courtship of another doe. That leaves the door open for other, less impressive bucks to sweet talk a receptive doe.

By the end of the rut, after weeks of challenging suitors and chasing does, bucks are exhausted, losing up to 25 percent of their body weight. They discard their rack and replentish their reserves in time to do it all again at same time next year.

Is the moom out tonight?

By J.T. Fleegle
Wildlife Biologist

Type in moon and deer movement on any Internet search engine and watch the hits pile up. The same can be seen on any hunting website or message board. There are countless charts and tables correlating moon phase and position with deer feeding, daytime activity, nighttime activity, estrous cycles, breeding, even fawning. Humans have worshipped the moon. Remnants of a moon-based religion can even be seen in the Christian calendar. There, of course, is the sap moon, the planting moon, the hay moon, the harvest moon, and the hunter's moon that tells people the time of year they should tap maple trees for sugaring, plant crops, cut hay, harvest crops or hunt game. If human behavior is affected by it, then why wouldn't it affect more primal beings, like deer?

Because deer are a popular game species, figuring out where they are going to be and when is important to those pursuing these elusive animals. So what makes a deer tick, or in this case move from point A to point B? Deer are crepuscular, which means they are most active at dawn and dusk. This is well documented by casual observation and scientific research. The amount of movement is what varies. Does the moon play a role in the daily and monthly travels of the average doe? Do bucks turn an eye to the night sky to check the phase of that most prominent heavenly body? By all accounts, the answer is no. Scientific research on this topic is sparse, but data that do exist show that movement and activity are not affected by the moon. GPS-collared bucks in Pennsylvania showed no change in movement between full and new moons. The same goes for bucks studied in Texas. In Maryland, moon phase was not a consistent indicator of buck movement or activity.

There are environmental, biological, and man-made factors that do influence deer activity and movements. Weather, temperature, food availability, time of rut, deer individuality, and hunt pressure all can play a role in where a deer goes and when. And they likely override any effect the moon might have. Someone once said that deer are driven by the need to feed and the need to breed. In other words, survival of the individual leads to the survival of the species— the goal of every creature. Our quest to explain deer movements based on one factor is an oversimplification of a complex process with countless numbers of variables.

To say that theories of the effects of the moon on deer movements are debatable is a gross understatement. However, calendars, charts and tables are produced and sold every year. Unfortunately, deer don't get a copy.

New in town...

By J.T. Fleegle
Wildlife Biologist

It's an exciting time: moving out, new things to experience, new places to see, new deer to meet. That's right, deer! Every year, thousands of young deer leave their mothers to seek their fortunes in the world.

For the first year of their life, deer live on their natal range, and learn from their mothers and other deer how to survive. But by the time they are a year old, things start to change. Right around the time does are about to give birth to new young, they give the cold shoulder to their other offspring.

Young does usually take this in stride. Less than 20 percent of female yearlings disperse from their natal range. Young bucks are another story. Seventy percent or more of yearling males may disperse from their natal range. This exodus is split between the spring, when their mothers drive them off, and the fall, when bigger, more experienced bucks are winning all the scraping, rubbing and sparring contests in the area.

These social pressures drive yearling bucks as far as 100 miles from their "home town." The average is about five miles. But when a yearling buck heads off, he is driven by some calling that only he can hear. Sometimes fate is kind and he finds a nice patch of forest in which to grow old. Other times, the harsh realities of the unknown world strike. Six-lane highways, cliffs, rivers, hunters and predators often interrupt or terminate these trips.

In Pennsylvania, dispersal for one buck ended abruptly when he fell off a cliff to his death.

Where a yearling buck will stop, nobody knows. But how far they go seems to be related to forest cover. Studies,

So, if you see young deer showing up in strange places in May or October, they may be new in town.