This information is taken from the Rocky Mountain Elk Foundation. Hope it helps.
All in the Family
Elk and other members of the deer family belong to a group of animals called ungulates, the Latin word for "hoof." All ungulates have hooves. This large group used to be considered one order, but now "ungulates" refers to two distinct orders, Artiodactyla and Perissodactyla. The number of toes is the most obvious difference between the orders. Artiodactyls (elk, deer, bison, pronghorn, peccary) have an even number of toes. Perissodactyls (horses, elephants) have an odd number of toes.
Elk, moose, caribou, white-tailed deer and mule deer all belong to the order Artiodactyla and to the deer family, Cervidae. The males of these species grow and shed antlers each year. (Female caribou also grow and shed antlers.)
Like other ungulates, members of the deer family are herbivores -- they eat only plants. Their diet may include grasses, forbs (low-growing, short-stemmed plants), shrubs and trees (including limbs and bark).
Members of the deer family must eat and watch for predators at the same time. Elk fulfill these double needs by gathering in herds. In a group, at least one animal is looking up while others are eating. Even the animals that are feeding are constantly twitching and turning their ears to listen for unusual or warning sounds.
Some deer family members migrate, following their food sources as the seasons change. Some caribou migrate hundreds of miles twice a year as they follow the seasons. Most elk that live in mountainous country migrate to lower elevations as snow covers the higher elevations, then return as snow retreats in the spring and summer.
Wherever you live in North America, you are likely to be near at least one member of the deer family. White-tailed deer live throughout the lower United States; mule deer browse in the western states and provinces; moose inhabit riparian areas (banks of rivers and other bodies of water) across the north; and caribou can be found in northern Idaho, Alaska and Canada. Elk used to live across North America, but these days you are most likely to find them in the western states and provinces.
Each spring, male deer and elk begin growing antlers from bony bumps on their skulls called pedicles. Increasing daylight elevates the level of the hormone testosterone in the animal's blood, which triggers the growth of antlers. Antlers begin as layer upon layer of cartilage that slowly mineralizes into bone. They are light and easily damaged until they completely mineralize in late summer. A soft covering called velvet helps protect the antlers and carries blood to the growing bone tissue.
If you look closely at a deer or elk antler, you'll see grooves and ridges on it. These mark the paths of veins that carried blood throughout the growing antlers. When blood stops flowing to the antlers in August, they harden, and the velvet falls off or is rubbed off. The hardened antlers are composed of calcium, phosphorous and as much as 50 percent water.
An antler grows faster than any other kind of bone. It can grow up to one inch (2.5 cm) per day during the summer. Biologists are studying antlers in hopes of learning the secrets of rampant cell growth--secrets that may unlock cures to various forms of cancer.
In his second year, a bull elk usually grows slim, unbranched antlers called spikes that are 10-20 inches (25-50 cm) long. By the third year, antlers begin developing tines that branch from the main beam. By the seventh summer, a bull's antlers may have six tines each, weigh as much as 40 pounds (18 kg), and grow to a length and spread of more than four feet (1.2 m). Why would an animal need to carry around a rack of antlers that weighs so much? A large rack identifies a bull that is successful in finding food, lots of food.
A bull must consume huge amounts of nutrients to obtain the energy and minerals needed to grow antlers as well as the energy to carry them around. Large antlers also identify a bull that is able to defend himself against other bulls and against predators. This information is of great interest to female elk (cows) because they will mate with the strongest, most successful males -- usually the bulls with the biggest antlers.
Elk and other members of the deer family eat tough plants such as grass or twigs that most other mammals can't digest. Elk digest these plants in multi-chambered stomachs, a trait of the suborder Ruminantia. (Cattle, sheep and their wild cousins are also ruminants.) The root of the name comes from "rumen," the first of three or four chambers of a ruminant stomach. These chambers create a system for digesting tough plant fibers and extracting the maximum nutritional value from them.
To understand how this "super stomach" works, imagine a cow elk as she nips off twigs, clips leaves and crops grasses. This constant biting, pulling and clipping sends as much as 15 pounds (7 kg) of tough plant fiber into the elk's stomach each day. The unchewed material slides into the rumen, the first chamber. There bacteria and protozoa begin breaking down the plant material. Then the elk regurgitates her food (the cud) and ruminates (chews cud thoroughly).
When the cud is completely chewed, the elk swallows it again. The food particles pass through the rumen and into the reticulum, the second chamber, for even more digestion. Then the food passes into the omasum, the third chamber, where water is squeezed out and absorbed into the elk's body. Finally, the food passes into the abomasum, the fourth and "true" stomach, where it is broken down to the molecular level so that it can be absorbed by the intestine.
Secrets of Teeth
Like other deer, adult elk have sharp incisors for biting off plants, and broad, flat molars for mashing plants. Molars line both the upper and lower jaw, but incisors occur only on the lower jaw. Elk also grow two canines (also called tusks, ivories, whistlers or buglers) in the upper jaw.
When biologists want to determine an elk's age, they look at the teeth, not the antlers. Teeth are a better gauge because antler size can vary depending on the health of the bull, and cows don't grow antlers. To "age" the teeth, biologists place a cross section of an elk's tooth under a microscope and count the annual growth rings.
The type of teeth in an elk's mouth and the amount of wear they show can also indicate the animal's approximate age. To figure the age of a young elk, a biologist observes how many adult teeth have replaced the "baby" incisors and premolars. This transition is completed by the end of the third year. Older elk can be identified by the amount of wear on their molars because chewing tough plant fiber will wear down even the sturdiest of teeth.
In the Open
Although we primarily see elk in mountainous and forested terrain today, they are also well suited to open spaces. Some scientists believe that an elk's body and senses reflect adaptations for the lifestyle of a herd animal that once roamed the plains for its food.
An elk's long legs are packed with powerful muscles designed for speed and endurance. A strong heart and lungs pump blood and air to those muscles to keep them moving, and move is what elk do to find enough food to eat throughout the year. They also need to escape predators such as wolves, mountain lions and grizzly bears.
Elk have keen senses that enable them to identify each other over long distances and to detect approaching predators. Unlike human eyes that can see precise images, an elk's eyes are designed to detect movement, even the slightest shifting of grass as a predator approaches. To an elk, knowing that something is moving closer is more important than identifying the kind of animal approaching. And because their big eyes are on the sides of the skull, elk can see what is happening ahead of them and beside them, as well as most of what is going on behind them.
Likewise, their big ears can twist forward and back to capture faint rustlings and other sounds of movement. Elk also seem to have a superb sense of smell. Combine the sharp senses of a group of five, 10, or even 50 elk and it's easy to understand how they avoid predators.
In the next two sections, "Where Are The Elk" and "Elk Through The Seasons," you'll discover how their habitat and behavior also help them to stay safe.
Just what is habitat, anyway? It's food, water, shelter and space. These are the four basics for all animals -- whether it's elk, elephants or elf owls -- and people, too.
The need for food is obvious. Picture a 900-pound bull elk grazing in a meadow of bunchgrass. The bull's hoof thumps down beside the nest of a field mouse. When the mouse panics and flushes, it's pounced on by a shrew that weighs no more than a quarter. Both the elk and the shrew rely on the same habitat -- and are driven by the same hunger.
Well actually, the shrew may be a little hungrier. Elk need 10 to 15 pounds of vegetation per day, but shrews have to eat their own weight in insects, earthworms or mice every day or starve. Elk can go a bit longer between meals. But like all animals, they cannot survive for very long without food.
Water is just as critical. Your body, an elk's body, a weasel's body... is all wet. If all the water in your body were removed, you would weigh about as much as a dictionary.
Naturally, elk and other animals are drawn to water holes -- springs, seeps, lakes, creeks -- but there's more than one way to come by water. A sharp-tailed grouse that shares grasslands and wild rose thickets with elk can get all the water it needs by sipping dew and eating juicy plants. Elk use these same techniques, and they also eat snow to quench their thirst.
After getting enough food and water, elk look for shelter. Shelter works two ways. It protects animals from cold, rain and snow. And it gives them a place to hide from predators.
On a bitter, cold, snowy day, a band of elk may "hole up" in a big stand of spruce trees. These trees form a great green blanket, holding warmer air near the ground. The spruce also take the bite out of the wind. And their tightly woven branches catch much of the snow before it hits the ground. This same patch of timber also offers shelter (and food) to a variety of songbirds, chickadees, nuthatches, grosbeaks -- and maybe even a red fox.
When people and mountain lions are hunting elk in October, the elk head for the north slopes of mountains and burrow into thick stands of dark timber. Lurking among the deadfalls where pine martens live, the wary elk position themselves so they can smell, hear and see any intruder long before they themselves are seen.
Every animal needs room to roam. For a mature male mountain lion, that means a lot of room. A big tom can have a home range of more than 100 square miles. That's as big as an entire county in some states. Elk like to ramble, too. They have been documented trekking more than 50 miles in a single day.
But a ground squirrel may spend a whole year on a chunk of range no bigger than a football field. And a beetle may live out its life on a slice of elk country the size of a wading pool. The beetle needs its space -- the area in which it finds the critical triangle of food, water and shelter -- just as much as elk do.
Elk country is home to all sorts of wildlife -- from tiger salamanders to zebra swallowtails to cutthroat trout. These creatures don't have antlers or horns or big brown eyes. But they're all vital strands in the web of life.
When an old bull dies in February, coyotes, ravens vultures and magpies quickly clean up the meat. Next spring, gophers gnaw on the bones for calcium and other minerals. When one of the gophers dies, beetles eat its decomposing carcass. And what's left over decays into the earth and is reborn as more nutritious grass.
All of the creatures in elk country have evolved over thousands--perhaps millions--of years to live in a specific habitat. When the rug is yanked out from under them -- when their food, water, shelter or space is suddenly altered or destroyed -- many of them cannot adapt quickly enough to survive.
Given a chance, the land can allow these animals to live naturally. All they need is habitat.
Populations and Habitats
From an ecological point of view, individuals of an animal species are less important than populations. Only populations can survive and adapt over the long term.
"Habitat" is the foundation on which wildlife populations are built. Habitat is a particular combination of (1) food, (2) water, (3) cover and (4) space needed by individuals and populations to live and thrive. The quantity and quality of these habitat components generally dictate the type and number of animals that can live and persist in a particular area.
Habitats are always changing -- seasonally, annually and over longer periods. Such changes can be the result of seasons (spring, fall, etc.), natural catastrophe (flood, drought, tornado, wildfire, etc.), plant succession (a field growing up to forest, for example) or human action (agriculture, dams, logging, pollution, etc). Thus, while the number of animals that any habitat can support always is limited, the actual population can sometimes vary drastically over time.
Section 3 - Elk Though the Seasons
When food is abundant and elk are healthy, they do what many animals do -- they play. They dash about leaping and kicking, squealing and calling to each other. They race in circles, taking turns to splash through ponds and puddles. Then, as suddenly as they started frolicking, they quiet down and return to feeding.
Instinct drives elk to behave in ways that promote the survival of their species by protecting and promoting their ability to reproduce. Their seasonal movements, their choices of calving grounds, feeding and resting places, even their social groups promote their reproductive fitness. How does play behavior fit into this? Biologists say that play is fun for animals, and also helps young animals develop the coordination and strength they need to evade predators. Play also helps keep adults fit.
Elk behave in similar ways wherever they live, but the details vary with specific habitat. For this discussion about behavior, we will follow a generic group of elk living in the mountains of the western United States.
On the Move
Lengthening days, warming temperatures, and melting snow all signal the start of spring movement for many elk in the Rocky Mountain region. They follow the melting snow to find newly exposed fresh vegetation at increasingly higher elevations. This migration may take only a few days or it may go on for two months.
Bulls begin to migrate first. They move more quickly and to higher elevations than cows and young elk. Cows often begin migrating before they give birth to their calves. They may return to the same range every year, using similar routes and river crossings. They stop to give birth and allow their young to grow for several weeks. By late June or July, they've resumed moving into higher country where they will find rich summer food.
Not all elk migrate. If they have enough food, water, shelter and space, they may stay in the same area year round. For example, some elk in Yellowstone National Park stay near thermal areas during all seasons because the warmth from under the ground keeps snow melted and plants growing even in the coldest of winters.
New Elk Arrive
Most cows have been pregnant since early October, but the most rapid fetal development occurs in the last six weeks. (Gestation is 8-1/2 months.) The young are born from mid-May through early July, depending on where the elk live. Calving time generally coincides with the period when the most nutritious food is available.
When a cow is ready to give birth, she often leaves the group to find a site that other elk seldom visit. This strategy helps her avoid predators that may have learned to hunt in places that elk frequent. She may select a site in an open, brushy area or perhaps in an area of thick trees.
A newborn calf is slow to get up on its feet and can't run fast or long. Instead, camouflaging coloration (its spotted coat) and an apparent lack of odor enable it to escape detection by most predators. The cow also helps hide the calf by eliminating any signs of her calf that a predator might detect. After giving birth, she devours the placenta and any soil or vegetation soaked by the birth fluids. She continues to clean the site by eating the young's feces. To avoid leading predators to her young, she grazes away from the hidden calf and returns to nurse it only a few times a day. If a predator approaches, though, she will attack or try to lead the animal away from the calf.
Even with all these strategies, a cow often loses her calf to bears, coyotes or other predators in the first three weeks. If a calf survives its first few weeks and joins the group with its mother, it is usually out of danger for a while. By that time, the calf can run fast enough to escape most predators, and it benefits from the safety of the group.
By July, cows and calves begin forming nursery groups. The size depends on where they live -- smaller groups might gather in a densely forested area, larger groups might gather in open valleys and prairies.
Within the larger herd, calves form smaller groups that center around one cow at a time. This cow seems to act as a "baby-sitter" for the calves while their mothers graze and rest. The calves respond as a group to the signals of the baby-sitter, a strategy that eliminates confusion when danger threatens and so helps protect the calves. It also allows the cows to spend most of their time eating, and to react quickly and better protect themselves.
By now, calves are safe from most predators. But if grizzly bears are part of the ecosystem, these powerful predators can catch any elk -- young, sick or merely unlucky -- that cannot flee fast enough.
Bulls usually spend the summer alone or in small groups at high elevations. In such places, they find rich forage, cool breezes and resting areas with fewer annoying insects.
Eating All the Time
Elk eat almost constantly during the summer. They keep feeding morning, afternoon, evening and even in the middle of the night, although they feed more often at dawn and dusk. They are building up fat in preparation for the mating season and then the long winter. If people had to eat and chew their food as much as elk do in the summer, we would have less than 10 free minutes every hour for other activities.
One elk feeding alone is vulnerable to predators, but elk feeding in herds are much safer. At least one animal will have its head up, listening and watching for trouble while the others eat. Elk are even safer when they are resting and ruminating.
Elk tolerate heat much better than the mule deer that often share the same summer habitat. Deer seek shelter and may stop feeding during a hot spell, but elk can sweat more to cool off. Still, during a hot spell, they may retreat to north and east slopes to take shelter among the trees. They may also stay near water, and sometimes they stand in a stream or pond. Elk will sometimes wallow and cover themselves in mud, which absorbs body heat as it dries and also protects them from biting insects. Elk might also head to cooler, breezier high country.
Bull elk also carry around "air conditioners" that cows don't have -- antlers. Air cools the blood flowing through the velvet, which then helps to cool the bull's body.
The Rut Begins
Shortening days, cooling temperatures, and snow in the high country all signal the start of the rut (elk mating season). Elk begin moving to lower elevations. Mature bulls move in among a group of cows and calves. These groups, called harems, are the scene of constant action from September through October, and sometimes through November.
A harem is usually smaller than the large cow/calf herds of summer and lacks the male yearlings. These adolescent males are usually driven off by the mature bulls or by cows intolerant of their presence. Sometimes, however, these young males remain near the harem, and often seem confused and unsure of their role.
By September, a bull's antlers are fully grown and almost ready for the displays and battles to come. The bull removes the tattered velvet and polishes his antlers by rubbing them on trees, shrubs and even the ground. Vigorous rubbing also releases his pent-up energy and leaves behind his scent to let other elk know that he is around.
If mud is available, bulls also wallow during mating season. A thorough mud covering cools off an over-heated bull, spreads his scent evenly over his body, and makes him look even more imposing.
The biggest bulls are animals in prime physical condition and may be six to eight years old. Younger bulls may try to butt in -- they are physically able to breed by their second summer -- but they seldom get a chance to mate.
When the rut begins, bulls begin to bugle. The sounds they make are among the more haunting and beautiful in nature, as memorable as the howls of wolves and the calls of loons.
A cow listens to the bugle for clues about the bull's size. A bugle, like a human voice, varies with the individual, but the older, larger bulls usually bugle more loudly than their young rivals. Their bugles advertise their presence and fitness to both females and other males. They also bugle to announce or accept a challenge from another male.
A cow can also tell the quality of a bull by the size of his antlers and body. During the rut, she has plenty of opportunity to observe the bulls as they "show off" to each other.
When bulls display their antlers and body, they are gauging each other's fitness and ability to defend the right to mate with the cows. A young male will probably retreat rather than engage in a fruitless battle with a mature bull. But bulls more equal in size typically confront each other.
Before a fight begins, the two bulls display their dominance by bugling and thrashing the ground with their antlers. They might march side by side, then suddenly turn, walk farther, or begin their fight. Then the bulls lock antlers and shove each other with all their might.
Fighting is a show of strength, not a battle to the death, but bulls do get hurt. If they stumble while their antlers are locked, one animal may be stabbed by the other's antlers. Mature bulls often sustain injuries every year.
When the cows come into estrus ("heat"), the mating begins. A bull elk must be ready -- a cow is receptive for mating less than 24 hours. She won't be willing to mate again until her second estrus cycle arrives in 20 days. Cows can have up to four estrus cycles each season, but most cows become pregnant during the first or second cycle.
On the Move Again
Harems disband when the rut ends. Cows regroup, and bulls of all ages may gather in bachelor groups. Both sexes eat as much as they can in preparation for the coming winter, a time of sparse food.
Elk will stay on their summer range as long as possible because the food is much more nutritious than what they will find on their winter range. But as snow begins to pile up in the high country, the elk are on the move again. They travel until they find slopes with less snow or no snow at all.
Cows and bulls often occupy different areas of their winter range. Bulls may retreat to high, snowy meadows where the food is adequate but not especially nutritious. A group of cows and calves may inhabit a south-facing slope that is free of snow and covered with nutritious grass. This behavior ensures better survival for the cows and calves.
In the winter, elk eat less and rest more. Some biologists believe this is a logical strategy for conserving energy and fat reserves. Other biologists suggest that elk may need to rest more because they have to ruminate, or digest, their food more. Their winter food -- dried grasses and twigs -- is harder to digest than their summer food. And if they live in snow country, they actually expend more energy if they must paw through snow to obtain that food.
When the snow gets too deep -- usually more than one foot (30 cm) -- elk may look for shrubs to eat or move to forested areas where they can eat twigs and bark. Thick stands of trees also shelter the elk from wind and cold.
Winters with heavy snow aren't necessarily a problem for elk. But if the winter is extremely cold, has exceptionally deep snow, and lasts a long time, many elk may die. Those that survive a severe winter are still in danger because their fat reserves are depleted, and the remaining vegetation is at its yearly nutritional low point. An adult elk may starve in that lean time before the new growth of spring begins.
Interesting Questions and answers
What do Battling Bulls Endure During the Rut?
Like a heavyweight fighter entering the 15th round, bulls nearing the end of the rut are haggard and beaten to exhaustion. Sleeping little, eating even less, and hopped up on rivers of testosterone, the biggest bulls can lose up to 20 percent of their body weight protecting their harems by the end of the rut. Fighting bulls receive on average 30 to 50 wounds each season. Antlers break, eyes get gouged. Sometimes bulls actually gore their opponents to death. Far more bulls succumb to infections from their wounds.
After aspen leaves fall and snow blankets the high country, the bugles fade and the rut comes to a close. Most bulls go solo or pair up through November and some of December to lick their wounds and hide from hunters. By January, bulls set aside their grudges and group together until deep snow drives them to lower elevations.
What do elk like to hear?
Like hard-bitten bluegrass fans, elk like the high, lonesome sound. Evidence suggests that sounds toward the upper end of the register are most pleasing to their ears. High-pitched squeals and chirps spoken by a herd are a socially positive sound, much like the sound of children playing or a mother singing a lullaby. Conversely, low-pitched growls and barks serve as a warning, such as the bark of a spooked cow.
A bull’s bugle has a combination of both—the high-pitched whistle carries over great distances and the low, guttural barks and grunts resound in dense timber, while also declaring a bull’s size. Often times after a bull runs off an intruding bull, he’ll slap the ground with his hoof and give a series of concussive woofs.
Scientific data on how high, low and far elk can hear is fuzzy, but biologists speculate an elk’s hearing is comparable to a white-tailed deer’s. In other words, formidable—especially since they can rotate their ears a full 180 degrees, allowing them to pinpoint possible threats, such as a hunter who didn’t see the pinecone underfoot until it was too late.
Why Do Elk Bite Trees?
First off, elk won’t gnaw just any tree. Strong resins course from roots to needle tips in the conifers prevalent throughout western elk country. These resins make both needles and trunks unsavory to elk in all but the direst circumstances. Smooth, soft white aspen trunks are a whole different story.
The skin of aspens is able to convert sunshine to chlorophyll the same way green leaves do on most plants. Even in the heart of winter. So the inner bark—the cambium—stays green year-round. Better still, it has a nutritional value approaching that of grass hay for elk. Small wonder that they eat this cambium with relish, especially during the lean times of winter and early spring.
The shallow flesh wounds inflicted by elk teeth seldom cause a tree real harm. Only desperation will drive elk to girdle aspen, stripping bark all the way around a trunk, dooming the tree to slow starvation. Most of the time the only lasting effect is a stippling of black welts—the elk “graffiti” so familiar to those who chase elk in the quakies.
Why do elk eat bones? (never knew this!!)
Elk will indeed indulge in a bone meal from time to time. Elk have been known to chew on bones as well as swallow them whole. According to Valerius Geist, wildlife biologist and cervid expert, elk may even eat carrion and sage grouse chicks in addition to bones and shed antlers.
During antler production, bulls require roughly 100 grams of protein each day, increasing their need for crude protein by 50 percent compared to the rest of the year. Cows, during gestation and lactation, also seek out supplemental sources of protein and minerals. Antlers contain high levels of calcium and phosphorous, but are mostly made up of protein.
Biologists don’t think elk have any particular affinity for the bones of their kin. Since elk live in herds on well-established ranges, they eat the bones of other elk simply because they are the most available source of protein and minerals.
Why Do Cows Separate from their Calves Soon After Giving Birth?
The first few weeks of an elk’s life are some of its most perilous, but calves have a few tricks to escape the teeth of predators. Cows leave their calves soon after birth to avoid drawing unwanted attention to them, returning only a few minutes a day for short suckling bouts. The rest of the time calves lay motionless in the grass doing their best impersonation of a rock. Their spotted backs provide camouflage and they are nearly scentless to elude keen noses. If a calf feels danger is close, it may bleat for its mother. Depending on the size and number of predators, a cow may either attack with sharp hooves or do her best to distract and lure them away. Calves are typically born around the first of June, and with luck, they will be up and running with the herd before July.
Last edited by Colorado Rick; 08-17-2008 at 08:53 PM.