NOVA explores the breeding, migration and survival patterns of the Rocky Mountain elk in a unique film, made totally under natural conditions. Telephoto lenses were used so as not to disturb the animals; filmmakers spent 18 months tracking the elk through the breathtaking Wyoming Rockies.
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00:36programming on public television.
00:57The Rocky Mountains of Wyoming.
01:04On these rugged peaks and in the sheltered valleys of the Yellowstone River lives a creature
01:12that embodies the awesomeness, solitary grandeur of wilderness.
01:18This is the story of the elk, monarch of the mountains.
01:37Ten million elk once roamed this continent from Maine to California.
01:48Only 5% of that number remain.
01:58Today large herds of elk exist only in remote regions of the Pacific Northwest and here
02:04in the Rockies.
02:08And although the elk are protected from humans, they still must endure the hardships of nature.
02:18Winter in these Rocky Mountains is pristine and pure with a serene beauty, a deceptive
02:32peace.
02:33Winter here can be bleak and brutal with ceaseless winds and temperatures near 30 degrees below
02:39zero for days on end.
02:42For the entire Rocky Mountain ecosystem, all the plants and animals that inhabit this vast
02:47range, winter is a season of hardship and cruel truth.
02:52Only the strong will live until spring.
02:55Each creature will spend all its energy trying not to freeze or starve to death.
03:00Their survival is all that matters.
03:06This is early winter.
03:07Bands of elk like this one huddle on windswept ridges at 10,000 feet where the snow is blown
03:13clear of the still abundant grass.
03:16Only in winter do bulls, cows and young come together like this for warmth and for protection
03:20from predators like grizzly bears and coyotes.
03:25They are ever watchful, always on the alert.
03:34But the ridgetops won't sustain them for long.
03:37By December, as the snows deepen, the elk migrate down from the high meadows to protected
03:42valleys below.
03:48Here it's warmer and the snow can usually be pawed away to get at the grass.
03:57It's not unusual during a hard winter for many small bands of elk to drift together
04:01into a herd of a thousand or more.
04:07Coyotes are the elk's ever-present winter companions.
04:10They are predators, opportunists, on the lookout for weakened animals.
04:14For them, survival requires that they kill or wait for an animal to die on its own.
04:21Mule deer, like this one, often share the same winter range as the elk.
04:29Except in the harshest winters, they don't compete with the elk for food.
04:34The elk are grazers, ruminants who prefer grass.
04:41The deer are primarily browsers.
04:44They live mainly on shrubs and bushes, leaves and twigs, brambles, bark and dry grass.
04:57But during extremely bad winters when food is scarce, the elk will be forced to browse.
05:03To survive, they must eat.
05:05And if heavy snow and ice make grass inaccessible, they turn to less nutritious but plentiful
05:10chokecherry, willow, juniper and sage.
05:17They burn more energy finding, chewing and digesting this diet than they gain from eating
05:22it.
05:25So in spite of eating their fill, they lose both weight and body heat.
05:29And as the winter goes on, they become increasingly ill-equipped to withstand cold, disease or
05:34predators.
05:37Winter mortality is high throughout the Rockies.
05:40But for the largest creatures, like the elk, highest of all, 15% will die before spring.
05:49The winter snows seem endless and may go on for five months or more.
05:55The young, the old and the disabled suffer most.
05:58Valley deep snows and sub-zero temperatures have made the already difficult task of finding
06:03food and keeping warm almost impossible for this ailing bull.
06:08He is thin and weak and moves slowly to conserve energy.
06:12Much of his heavy winter coat has gone because of disease and parasites.
06:16He cannot maintain normal body temperature and so exposure may eventually kill him.
06:26Coyotes sense the bull's weakening condition.
06:28They will watch and wait as his battle against the elements continues.
06:39A healthy mule deer has little to fear from these coyotes.
06:47They will, like the magpies, feed on the carcass of a careless baby deer or whatever they can
07:02find to survive.
07:05The coyote's niche in the ecosystem is not a particularly appealing one from a human
07:09standpoint, but it's essential to the health of the whole community.
07:17The coyotes and black bears, grizzlies and mountain lions eliminate animals that can't
07:22survive on their own, finishing a natural process begun by disease and injury.
07:33It is only predation on some animals by others that allows a complex wildlife system like
07:38this one to exist.
07:54The elk tries to conserve his failing strength.
07:57Lying down keeps him warmer than standing up and he uses 25% less energy to do it.
08:08Only hunger or serious threat will make him move.
08:38Coyotes could never bring down this bull if he were healthy.
08:45They will wait for weeks if necessary until he's too weak to resist them.
08:50Even in his emaciated condition, he will provide many a winter meal.
09:02The bull no longer has the strength to travel long distances to find food or even to dig
09:07through the snow to the grass beneath it.
09:10Other foods are nearby and he must eat something, so he takes whatever food he can find.
09:25These limber pine needles may sustain him briefly, but they aren't very nutritious.
09:33And because of their chemical composition, they may actually interfere with his ability
09:40to digest other food and so hasten his death.
09:53The bull has made his final bet. Now past recovery, he too will simply wait.
10:02In his dying moments, he is not alone.
11:02These healthy bulls may have grazed alongside him in the summer or done battle against him
11:06in breeding seasons past. It is impossible to know, but perhaps they have come to say
11:11farewell to a fallen comrade, to pay final respects, to offer final challenges.
11:32The death of one may ensure life for the others, as the scarce resources of a bitter winter
11:39will now go to sustain fewer, stronger animals. One is more likely to live to see the spring.
12:10The survivors depart to search for food and to shelter from the thickening blizzard.
12:28The short, dark days of the long, cold winter go on and on.
12:36A few mountain streams flow free, but ice cold all winter long.
12:45The river otters seem unperturbed by the cold. Their thick coats are warm and water repellent.
12:52Otters need only a bit of open water to fish in. Though their diet consists mainly of trout
12:58and smaller fish, they will feast occasionally on a wayward rabbit.
13:04The bighorn sheep pause through the snow to get at the tough alpine grasses and lichens that it lives on.
13:11A distant cousin of the elk, the sheep spends the winter at high elevations on rocky ledges.
13:24By mid-February, the back of winter is broken. More snow will come, but the sun has warmth to it again.
13:32Mating coyotes howl in the distance. This bull elk, blind in one eye,
13:38is lucky to have survived the worst of winter with such a handicap.
13:47The thaw exposes patches of bare ground for the first time in many months.
13:53This mother coyote and her nine-month-old juvenile pups begin reclaiming their territory,
13:58marking it as their own by urinating around its boundaries.
14:02The size of coyote litters varies depending on the overall population and the availability of food.
14:08In bountiful years, litters will be large. In hard years, sometimes only a single pup will be born.
14:14In the welcome first warmth of early spring, the young coyotes can take a little time away
14:19from the business of survival for some playful ruthousing.
14:24But their mother soon breaks up the fun and gets her nearly grown pups back to work.
14:31By early March, many of the mountain streams are flowing free.
14:37The ice is out, the snow is disappearing, and the first shoots of new green grass
14:43will soon appear on the slopes of the mountain.
14:47This is a sign that winter is coming.
14:51By early March, many of the mountain streams are flowing free.
14:55The ice is out, the snow is disappearing, and the first shoots of new green grass
15:00will soon appear on the south-facing slopes and riverbanks.
15:15Although it won't happen overnight, there's no doubt that a new season has begun,
15:20a new life.
15:50As new life begins, old cycles are completed.
15:55The bull elk's skeleton, long since picked clean, decomposes in the warming April sun.
16:01The bones will be completely consumed by small animals.
16:07The new season stimulates changes in the living elk as well.
16:11The length of the bones will increase, and the size of the bones will increase.
16:18The length of the day affects the bull's hormonal balance, which controls antler growth.
16:24As the days grow longer, antlers suddenly let go,
16:27and the bulls shed the majestic racks they carried all winter.
16:31The process is clearly uncomfortable and quite awkward,
16:34since usually only one antler is lost at a time.
16:37But a membrane quickly covers the raw spot,
16:40and within a week, a new set of antlers begins to grow.
16:45Once their antlers have been shed, bulls become quite solitary
16:49and begin to move up to the high mountain pastures for the summer.
16:56Spring brings thousands of migrating birds to Wyoming along the mountain flyway.
17:01Among them are 43 species of ducks.
17:04These barrow's golden eyes will mate here and fly on further north to raise their brood.
17:15The Canada geese, too, use the wetlands of the Rockies.
17:19They breed here in late March.
17:21Generation after generation will return to the same breeding grounds,
17:25taking advantage of the bounty of burgeoning spring.
17:32Strutting and honking with characteristic aggression,
17:35the Canada geese loudly proclaim that this is their territory.
17:40Then, like the golden eye, they'll fly on into Canada
17:44to hatch their eggs and raise their goslings.
17:57Spring comes very late to the high mountains,
18:00but in the sheltered lower meadows where the elk have wintered,
18:03green bursts forth by late April.
18:09The Canada geese, too, fly on into Canada
18:12to hatch their eggs and raise their goslings.
18:15The Canada geese, too, fly on into Canada
18:18to hatch their eggs and raise their goslings.
18:21The Canada geese, too, fly on into Canada
18:24to hatch their eggs and raise their goslings.
18:27The Canada geese, too, fly on into Canada
18:30to hatch their eggs and raise their goslings.
18:33The Canada geese, too, fly on into Canada
18:36to hatch their eggs and raise their goslings.
18:42Tender leaves of grass and frothy aspen catkins
18:45soften the harsh contours of the lowlands
18:48that only a few weeks ago were three feet deep in snow.
18:52Cows will have one calf a year
18:55throughout their lifetimes of ten to fifteen years.
18:58The mother-calf relationship is the only durable bond among elk.
19:01The mother-calf relationship is the only durable bond among elk.
19:04The mother-calf relationship is the only durable bond among elk.
19:22Calves of both sexes generally stay with their mothers
19:25until they're a year old.
19:28As soon as the calves' wobbly legs have steadied,
19:31they begin the migration up to the lush summer range.
19:38The cow can leave her baby to go a short distance away to graze,
19:41but she chooses an open spot
19:44that gives her a good view of any approaching danger.
19:52The calf's mortality rate is staggeringly high.
19:55Fifty to seventy percent of them will die in their first year.
20:00The elk calf's only defense is to hide,
20:03to lie perfectly still in the best cover it can find.
20:08The calf has almost no scent for its first few weeks of life,
20:11so discovery by a predator, like a grizzly bear or a coyote,
20:14will most likely be accidental.
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21:19Fierce, drenching thunderstorms begin in June
21:22and last throughout the summer.
21:24Such an abundance of water ensures lush growth
21:27of nourishing plant life for the whole ecosystem.
21:31But the precipitous terrain simply can't hold
21:34these millions of gallons of water.
21:37Mountain streams, already swollen from melting snow,
21:40become roaring, pounding, boiling torrents.
21:43For some members of the wilderness community,
21:46these swift and turbulent streams pose no problems.
21:50The oozle, or rocky mountain dipper, thrives in these waters.
21:54It actually dives to the bottom,
21:56opens its wings about halfway for balance,
21:59and walks along underwater,
22:01feeding on insects and the larvae of stoneflies.
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23:07The runoff swollen streams lie between the elk
23:10and their high summer meadows.
23:12They must cross during the migration,
23:14and crossing can be disastrous.
23:16The current is swift, deep, and icy cold.
23:19It is difficult for the birth-weakened cows,
23:22still thin from the hard winter,
23:24to make it safely to the far shore.
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23:41Calves are virtually abandoned
23:44as their mothers try to find the best place to cross.
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24:17This unusually large band of cows and calves
24:20has been gathering on the near side of the river
24:22for several days,
24:24unable to cross and unable to turn back.
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24:45Finally, in spite of the treacherous waters,
24:48they plunge ahead.
24:50The adults go first.
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25:04For the calves, now only a few weeks old,
25:07crossing seems almost impossible.
25:09If their mothers weren't already on the opposite side,
25:12most would probably never attempt it.
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25:45Some calves try to cross with their mothers
25:47but are swept away downstream.
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26:07The calves are at the mercy of the rushing water.
26:10Their legs are too short to reach the bottom,
26:12so they can't push themselves off and jump to shore,
26:15and their bodies are too light to resist the racing river.
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26:27They must grab the bank where they can,
26:29and still battling the current,
26:31try to pull themselves to safety.
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26:40Nervous mothers smell each calf as it emerges
26:43and continue searching for their own young ones,
26:45unable to do anything for them but wait.
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27:07The calves are instinctively unable to give up.
27:11They will fight to cross the river until they have succeeded
27:14or are swept away by the icy waters.
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28:23With the last of the calves safely ashore,
28:26the large band disperses.
28:28Small groups of cows and calves continue on their way.
28:32Grooming and cleaning help both relax after their long ordeal.
28:36Calves imitate their mothers and learn the rituals of an elk's life.
28:40The elk's migration will take them up 5,000 feet or more above their winter range
28:45over a distance of 10 miles.
28:47They'll need to feed constantly as they travel.
28:54Elk calves will rely on mother's milk as long as they can,
28:57two and a half months or more.
29:02But sometimes their mothers make it a little difficult.
29:11And some calves get a little carried away.
29:19This mother and baby both seem to be getting what they need,
29:23a good meal and a well-deserved rest.
29:32A stretch and a high-spirited frolic.
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30:42Even the cows kick up their heels a bit.
30:50But this one clearly isn't interested in sharing her private waiting pool with anybody.
30:56Certainly not this yearling male.
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31:12As the elk make their way up to the summer range,
31:15the cinnamon teal engage in a showy mating dance.
31:18Flaunting their glorious colors as they skitter across the pond,
31:22the males court the females with all their hearts
31:25in the lengthening early summer light.
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31:39By late June, the loosely organized cow-calf bands of 20 or 30
31:43are well established in the lush mountain meadows of summer.
31:47Scavengers like the cowbirds profit too from summer's abundance,
31:51keeping the elk free of ticks and lice while they feed themselves.
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32:06Midsummer is a time of plenty.
32:09Grass, the elk's favorite food, is nearly unlimited and it is rich in protein.
32:14The summer diet has an immediate effect on the elk's appearance.
32:18They put on muscle and weight.
32:20They shed their bulky winter coats and grow short, sleek summer ones.
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32:27The new calves weigh only 25 pounds at birth.
32:30By summer's end, they'll have grown to ten times that size.
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32:36Cows, their calves and yearlings will roam throughout the alpine forests
32:40and meadows all summer long.
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32:45Dangers are few and food plentiful.
32:48The elk grow strong and fat in the bounty of July.
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33:03Nearly 30,000 elk will share the summer range of the Yellowstone Valley.
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33:14The bulls spend the spring and summer near the cow-calf groups
33:18but are segregated from them.
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33:24Their priority is to prepare for the fall breeding season, the rut,
33:28by building up size, strength and antlers.
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33:37The antlers begin as deposits of cartilage tissue
33:40produced by special cells in their tips.
33:43As they grow, the cartilage is mineralized and changes to bone.
33:47They can grow as much as one inch a day.
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33:58The bulls may be completely solitary until the fall
34:02or may live in loose bachelor bands of 40 or 50 other bulls.
34:06They are not at all concerned with the cows and the calves
34:09though they are within one mile or so of them.
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34:32Wilderness predators too enjoy the abundance of summer.
34:36The great grey owl is skilled at silent and effective aerial attack.
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34:46Her keen eye and deadly talons make short work of an unlucky rodent.
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35:01The coyote prowls the summer ranges well
35:04in search of field mice and other small animals.
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35:15Coyotes depend primarily on vision to guide their hunting.
35:19Sound and smell are also important.
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35:26Patience and persistence too are among his best tools.
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35:33Coyotes aren't fussy eaters.
35:36A chipmunk,
35:39a flicker,
35:42a marmot.
35:45Any of them would make a good meal for the coyote's hungry pups.
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35:56They're too small to hunt on their own
35:59and so are totally dependent on the adults for food.
36:03Both parents as well as year-old juveniles will hunt
36:06and bring back food to the constantly hungry mouths at the den.
36:12Coyotes usually live in pairs
36:14but have been known to live in packs of 10 to 20 animals.
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36:35This mother, lying in wait at the entrance to a gopher hole
36:38can't move a whisker or she'll give herself away.
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36:53The coyote must keep trying until she succeeds.
36:56To give up because prey is too hard to capture
36:59would mean that soon the animal wouldn't have the strength to hunt
37:02and the pups would soon starve.
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37:10The overwhelming beauty of summer in this mountain wilderness
37:13is nowhere so evident as in the abundance of wildflowers that carpet the valleys.
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37:34This dainty mule deer crowned with his velvet antlers
37:37luxuriates in the glory of summer.
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37:56A red-tailed hawk sails on the wind
37:58as he oversees this mountain kingdom, domain of the elk.
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38:06From no other vantage point is the precious wildness of these mountains
38:10so visible, so clear.
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38:34Far below, a herd of elk graces the highest meadows
38:38unaware of the watchful eye of the hawk above.
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38:52By mid-August, the elk are all in prime physical condition.
38:57For the bulls, the change over the summer has been spectacular.
39:01They have grown fat with heavy, showy winter coats.
39:05Their antlers are massive and nearly full-grown.
39:08Still encased in the sensitive, blood-filled velvet,
39:11each pair of antlers will weigh up to 40 pounds when fully mature.
39:15Antler size and shape are good indications of a bull's status and age.
39:20Each year until he's five or six, a bull adds one new tine to his rack.
39:24Dominant bulls have large, elaborate, heavy antlers with many tines.
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39:35By the last days of summer, the whole animal community is humming with life,
39:39each part at physical peak, awaiting the challenges of fall.
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39:51This richly complex ecosystem, unspoiled by humans,
39:55is a pure microcosm of life in the wild.
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40:02The elk have been in the Valley of the Yellowstone for over 10,000 years.
40:07Today they thrive here, but tomorrow?
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40:13In 1854, the American Indian chief Seattle pleaded for all wild things.
40:18He said, what is man without the beast?
40:22If all beasts were gone, man would die from a great loneliness of spirit.
40:27For whatever happens to the beast soon happens to man.
40:31All things are connected.
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40:54Late summer again brings snow to the highest peaks of the Rockies.
40:59This season's shorter days trigger spectacular changes
41:02in the aspen and cottonwoods, skunk brush, and chokecherry.
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41:13Among the first signs that the elk's fall breeding season is near are these.
41:18Shreds of velvet, torn and bloody,
41:20draped upon the trees and bushes where the bulls have been grazing.
41:24Their antlers are fully grown by late August.
41:27The blood flow to them stops,
41:29and the velvet covering which has nourished them dries and peels.
41:34As the bulls begin to shed velvet,
41:36they move in among the cows for the first time since winter.
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41:47Once a living part of the animal,
41:49the velvet hangs like tattered rags from their majestic racks.
41:54The velvet itself is like skin growing over the antlers.
41:57Quite naturally, it bleeds as it separates from the antler.
42:01And when it dries up, the bulls apparently feel something.
42:07For they will try rather hard to rid their antlers of the now useless covering.
42:14They rub vigorously against trees and shrubs,
42:17and scrape and thrash in the undergrowth.
42:22For eight to ten hours, a bull will rub insistently against any handy object
42:26to scrape off the old velvet.
42:32Birds and small animals use the discarded velvet to build nests and dens.
42:38Occasionally they, as well as the bulls themselves, will eat it.
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43:04All the bulls tend to lose their velvet in the same week or two,
43:08which is hard on the individual trees and on their inhabitants.
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43:20Despite shedding velvet, the bulls are still quite tolerant of one another.
43:25But they may have benign shoving matches, early tests of relative strength.
43:31Their freshly exposed antlers are gleaming white and harder than bone.
43:36After shedding the velvet, bulls will rub them in the grass and the earth, darkening them.
43:42The rack of a prime herd bull may be five feet high and six feet across.
43:51As the equinox approaches, and with it the cow's brief period of fertility,
43:56the bulls become increasingly intolerant of each other.
43:59Earlier jousting escalates into serious sparring like this,
44:03as the bulls compete for dominance in the male hierarchy.
44:06Though grimly serious, these matches are not yet full-fledged battles,
44:10but tests of stamina and overall condition,
44:13and good ways to attract the attention of nearby cows.
44:18Successful bulls are big and well-muscled, with strong necks and shoulders.
44:23Their antlers are large, heavy, and elaborate in shape, impressive to look at.
44:28Superior antler growth indicates that the bull is in his prime,
44:32is dominant, and has had ample food all summer long.
44:36A huge rack like this one is a great advertisement for his overall condition and strength.
44:43September
44:47The September breeding season, called the rut, is not far off.
44:51The bulls are in a state of constant agitation and excitement,
44:55tearing trees and earth with a great outpouring of energy
44:59that makes them seem as large and impressive as possible,
45:02threatening to other bulls, but attractive to the cows.
45:06Displays and exuberant self-promotion will continue for weeks
45:10as the bulls wait for the cows to come into heat.
45:13This kind of behavior is common to other animals preparing for their breeding season.
45:19High on the rocky cliffs, the bighorns are getting ready.
45:23Bighorn rams are aggressive animals, especially during their breeding season later in the fall.
45:29They vent that aggression on other rams or on whatever is available, including a hapless sagebrush.
45:36The competition among them is intense.
45:38The standoffs, butting, threatening, kicking and shoving are all part of an elaborate ritual.
45:44They use these displays to help solidify the hierarchy
45:48that determines who will and who won't be doing the breeding.
45:58The dominant rams deliberately charge from the uphill side of perilously steep rocky ledges
46:04and use gravity to their advantage.
46:09A prime ram will weigh up to 325 pounds.
46:14Sparring like this is common, but serious injuries are rare.
46:23Their buttress-like horns are effective weapons.
46:28Unlike the elk's antlers, rams' horns are permanent fixtures which grow continuously.
46:38As with most species, the tendency among bighorns is to avoid dangerous fighting
46:43and settle differences with threats, visual displays and submission.
46:47But sometimes there is no alternative to a head-to-head clash between rival males.
47:27Breeding season has begun.
47:29It is for this that the bull elk prepare all year.
47:32They are in superb physical condition and in a frenzy of emotional intensity.
47:38Prime bulls between five to eight years old do most of the breeding, or try to.
47:43Their loud calling echoes through the mountains, luring mates and threatening rivals.
47:58In any elk herd, cows outnumber the bulls about three to one
48:02due to high natural male mortality and human hunting.
48:08Dominant bulls, like this one, will spend most of the next three weeks
48:12trying frantically to gather a harem of 20 to 30 cows
48:16and hold them together until each one has come into heat and been bred.
48:21A harem bull is always surrounded by rivals.
48:25He must keep constant watch on all his cows, driving them like a sheepdog,
48:29circling around them as they drift away.
48:33Only a few dominant bulls actively breed with the cows.
48:37The rest, the non-breeding males, seem to act as sexual stimulants
48:41to both prime bulls and cows.
48:45Harem bulls seldom rest or eat during the rut, so intense is their level of activity.
48:50A bull may lose up to 25% of his body weight during the rut
48:54and enter the winter season exhausted and underfed.
49:00The ability to avoid fighting is a valuable asset,
49:04so bulls roar and bellow at one another to assess their opponent's strength from a distance.
49:11In fact, the term rut, used to describe their breeding season,
49:14comes from the Latin word to roar.
49:21At the same time that he roars, the bull sprays urine,
49:24saturating himself with scent which, presumably, cows find irresistible.
49:30A deep, resonant bellow suggests to any listener that this bull is in superior condition.
49:37In addition to roaring and spraying,
49:40other aggressive displays become common as the intensity of the rut escalates.
49:47Bulls gouge the earth and tear at the ground with antlers and feet,
49:51not in anger, but in triumph.
49:54They horn at vegetation and drape their antlers and feet
49:57as if they were on the edge of a cliff.
50:00Not in anger, but in triumph.
50:03They horn at vegetation and drape their antlers with earth and grasses
50:07to make them seem larger.
50:14They rub violently against nearby trees.
50:19They dig in swamps and low-lying spots and wallow in the holes that result.
50:25Such aggressive displays attract attention to the bull's presence
50:28and emphasize his size and power.
50:31They advertise his evident superiority as a prospective mate and a deadly challenger.
50:38All during the rut, bulls roar challenges to one another
50:41as harem bulls struggle to keep control and lesser bulls try to take it away.
50:47They size each other up, prepared to do battle if necessary,
50:50but first trying to intimidate a would-be opponent into backing down
50:54before damage is done.
50:59The cows, meanwhile, are agitated as they come into heat
51:03and await their almost certain impregnation.
51:08At the height of the rutting season, back and forth,
51:11bugling and challenging and aggressive displays
51:14will not always resolve conflicts between two bulls.
51:22If a dominant harem bull is repeatedly challenged by a serious rut,
51:26who is not convinced to submit to the harem bull's superior position and power,
51:30a rare full-scale dominance fight may erupt.
51:40The dominant bull will use every ploy to avoid combat,
51:44but sometimes a challenger cannot be intimidated into retreat.
51:49A serious fight is preceded by a lengthy series of displays
51:53during which bulls do not take advantage of each opportunity to escalate the confrontation.
51:59Opponents will exchange loud calls until they come into sight of one another.
52:05There is spraying, horning of vegetation, and wallowing.
52:09The bulls will exchange loud calls until they come into sight of one another.
52:21There is spraying, horning of vegetation, and wallowing.
52:40There is spraying, horning of vegetation, and wallowing.
52:46Opponents will circle, but avoid looking at one another,
52:50digging and threatening as a cow looks on.
53:09It's a long and subtle process that can go on for hours.
53:39The head-on clash develops suddenly.
53:43Matched antlers lock and the elk wrestle with their powerful neck muscles.
54:09In this battle, neither bull is injured.
54:12Dominance is re-established and the herd bull returns to his harem.
54:40Controlling his cows with a special herding posture,
54:44the bull will also grind his teeth, bark, and hiss at them.
54:48Occasionally he'll gore a cow that gets out of line,
54:52so the herding behavior is serious and effective.
54:55Each cow will be receptive to being bred for only about 18 hours,
54:59so the bull must be constantly vigilant.
55:03Threats from challengers continue until every cow has come into heat.
55:11The harem may stay loosely together into early November.
55:15Then the cows will separate from the bull
55:18and form small bands with other pregnant cows and their six-month-old calves.
55:27The exhausted bulls will wander away
55:31and hover on the fringes of the cow-calf bands all winter.
55:44By December, the snows are deep on the high meadows
55:47and the elk are forced to migrate down to the lower winter range.
55:54The year has come full cycle
55:56and the cruelest season is upon them once again.
56:01The noble beast, the elk, monarch of these mountains,
56:05will struggle to survive the brutal winter to live to see another spring.
56:10In this Wyoming wilderness, the elk have found a balanced world,
56:14a natural home, now and for generations to come.
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