yellowstone in winter. look in any direction, and it takes your breath away. there is a power in this beauty -- a power so compelling that visitors are drawn to its wild splendor. they've come to yellowstone for christmas. right there! there's a bald eagle right in that tree. a bald eagle right there! look at that! good spot! they'll find a wilderness as pure

as the driven snow. to one devoted photographer, it's solace for the soul. [ wolf howling ] man: we can improve on some things, but we cannot improve on this. we can't improve on this at all. it's winter in the wilderness. it's christmas in yellowstone. "nature" is made possible in part by...

leave it untouched inspby your presence.re.. capture its image and preserve it forever. canon -- living and working together to appreciate today and care for tomorrow. the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. [ cheers and applause ] narrator: christmas always begins with this simple gift, with lights in the dark.

they light up the night and the cold, the heart and the soul. in jackson hole, wyoming, they light up a winter that is always white... and a season full of wonder. this is christmas in no ordinary place. december dawns cold and clear in the valley of jackson hole. already, the surrounding mountains are wrapped for the season in glistening sheets of ice and snow.

elk are gathering on their winter range, and not a moment too soon. the cold has come early. all the moisture in the air has frozen into sparkling crystals called diamond dust. up in yellowstone, 100 miles to the north, an icy fog settles in lamar valley. it's december 7th, and the mercury reads 45 below.

but the waters of mammoth hot springs are over 100 degrees. as the warm mist meets the bright cold air, it sugarcoats every twig within reach with layer upon layer of frost. the cold snap has caught these bison off guard. they're still up in the high country and must head down to easier wintering grounds.

all across yellowstone, animals travel the roads to save energy. and as the temperature drops, the crunch of snow rises to a rubbery squeak. a red fox, perfectly dressed for the weather, is already where he needs to be. just beneath the snow, insulated from low temperatures and high winds, is a vast network of tunnels, the winter quarters of mice and voles. the fox cannot see the mice under their white blanket.

but he can hear them. the trick is not to let them hear him.

winter reshapes the landscape by reshaping water. ice, snow, frost, and diamond dust -- it's all water in winter's grip. cold works the line between liquid and solid. molecules of water, captured by the cold, are stopped in their tracks. a river must keep on the move or be claimed by ice.

this precarious edge is the favorite spot of the dipper. it's a songbird that hunts aquatic insects year-round. insulated with special down, it dives in and out, all the while looking dry and comfortable. standing in bare little feet on the ice, it never seems to notice the cold. [ animal calling ] an otter family appears to have found a lost youngster, whose frantic calls carry up and down the river.

somehow, he's been injured and is favoring his left front foot. finally, he gets the attention he's been crying for. the family soon heads off again, but the youngster doesn't follow.

they need to find fish, and maybe he just can't keep up. when he finally enters the river, he heads in the wrong direction, swimming farther and farther from his family. [ calling ] the season is closing in. water slows down into ice. as the ice forms, it expands. and as it expands, it cracks.

when conditions are just right, the percussion of cracking ice ricochets off the mountains. to the challenge of ice and cold, add another -- wind.

winter is a time of limitation, of testing, of hunger. and it's just beginning. elk nibble the last dry twigs, but there is little nourishment. a moose browses in willows that have gone dormant for the season. bison retreat to the warmest spots in yellowstone, close by the thermals. heat rising up through the ground keeps the snow cover thin, but there is little to eat. everyone's task now is simply to endure. yet high in the fiercest peaks,

there's a small retreat that winter will never reach. the den of a grizzly bear. the bear is not asleep. since november, she's been in a state of hibernation. her heart beats a third of its normal rate. she breathes less than twice a minute. she won't eat or drink for up to five months. she won't urinate or defecate. she'll recycle her own waste into protein, losing weight, yet building muscle -- all while barely moving. safe from cold and hunger, she has mastered the winter wilderness. a human can make no such claim,

and yet be drawn to winter in yellowstone all the same. the first account of wintering alone here came from a legendary explorer and trapper named john colter. by 1806, he'd become one of the most able members of the lewis and clark expedition as it crossed an uncharted continent to the pacific. for three years, he'd endured every adventure and hardship -- hunting, starving, meeting new tribes, confronting grizzly bears. yet two months short of the expedition's return

to the comforts of st. louis, colter turned and headed back into the wilderness. on foot, carrying a rifle and a 30-pound pack, he headed up into an unmapped country called the yellowstone. there was no national park back then, no state of wyoming, just fierce, wild country no american had ever seen. what would john colter have witnessed as he reached the rim of lamar valley that winter 200 years ago?

like winter itself, wolves test a herd of bull elk.

the elk show themselves to be fit, but it's early in the season yet. the wolves of lamar will have to wait. photographer tom murphy is a modern-day adventurer who, like john colter, finds it hard to come in from the cold. for 26 years, he's spent part of each winter camping in the back country.

his book, "silence and solitude," is a profound account of yellowstone in winter. man: the reason i do this -- it's an opportunity to see this country in its wildest, most beautiful time. the cold and the snow drives most people away. the rewards are, you see country that nobody else sees. the best photographs -- there's been times that i've felt i could smell the air, i could smell the trees. if i can bring people these kind of images and they can feel that they're there, then they'll say, "i need to make sure that stays that way."

[ shutter clicks ] right here, in this early morning light, with this fog drifting around from the thermals, what's happening is, all this stuff reveals things that aren't normally this prominent. of course, the sun is coming up fairly quickly, and it's going to change the shadows. i need to sort of maximize my time, so i end up kind of frantic here,

shooting like this. things all of a sudden pop into sight. right now, all of a sudden, this tree just softened up... [ shutter clicks ] and came out of the fog. now, it's gone again. [ shutter clicks ] now the steam has moved in, obscured a bunch of other stuff, and made this one tree stand out even better with this wonderful bank of clouds behind it. narrator: in some ways, steam is what yellowstone is all about. its extraordinary geology is what inspired the creation of the park. the rarest of all thermal features are geysers, and yellowstone holds more of them than any place on earth. they require a perfect alchemy

of water, rock, and volcanic heat. much of yellowstone sits inside a giant caldera, the remains of an ancient and colossal volcano. more than three hundred geysers erupt here still as the enormous forces so close to the surface blow off a little steam. deep in december, the only way to drive into the park is by snowmobile,

or in antique contraptions called snow-coaches. these vehicles have been in service in yellowstone since the 1950s. by nightfall, the snow lodge at old faithful beckons with lights and warmth, a safe haven with a good meal and a comfortable bed. it takes something special to enter yellowstone completely -- in the cold and on your own.

the days are short in december, and tom murphy must make camp before dark. in the pack on his back, he's carrying all the comforts he thinks he needs. murphy: traveling in the back country of yellowstone in the wintertime takes a lot of stuff. this pack runs generally 70 -- for me, runs between 70 and 80 pounds. that's about as light as i can make it if i'm carrying camera gear, so this is what i got. first of all, this is a bag of food, which i always have way too much of. i have a stove. i always travel with a very large, very warm down jacket. these are the warmest mittens i've ever seen. even soaking wet, they're still really nice. a small emergency kit, and a head lamp.

i always have two water bottles. you can never drink too much water here. so this is my mshelr, an 8-foot-square nylon tarp with rubberized coating. you need to tie a knot that's easy to untie, because your fingers are going to be cold in the morning. a figure 8 is a wonderful knot. tie this one up here. wish i'd got a longer stick. i'll improvise by using the grommet on that knot, actually. this is the roof, here, flexible. okay, so there's my back wall, my roof -- that's pretty nice, actually. okay, there's a 3-pound down sleeping bag here, which is theoretically rated to 20 below zero. i'm going to fluff it up here, put it in here as soon as i can

so that down fluffs up and... is warm as soon as possible. and that's pretty much it. narrator: "pretty much it" doesn't look like nearly enough. a storm is moving across the mountains. tom is in for a bumpy night. by first light, a ground blizzard is sweeping down specimen ridge.

winds blowing 50 miles per hour whip the snow into a frenzy. interviewer: how was the night, tom?

well, i normally pick a place with less wind. the biggest problem i had was this thing flapping all night, keeping me awake. there's a little more snow in here than i'm used to, mostly because it'd eddy around right here. i see it looks like a ground blizzard out here. i'm sure this looks like i'm committing suicide, but... mostly mental, i'm not, i don't think i'm all that tougher than most people. i've got a mental idea that -- i mean, this snow is flying around here -- just water. but i have to think about, what i'm doing isn't really all that unusual, if you think that two hundred years ago, almost two hundred years ago,

when john colter went across this park -- you think about two hundred years ago, when john colter went across this park, he didn't have a down sleeping bag. he probably had a bison robe, which is pretty warm. it's definitely waterproof. and there's hair on bison about that thick, so it'd be very, very warm, but he would be lying down in something, just like i am, the wind blowing the snow right over him -- it probably buried him at night. and he'd just get up, shake that stuff off, and away you go. narrator: it's out on the land that tom truly becomes part of yellowstone's winter world.

a group of bison are making the steep climb out of hayden valley. after digging for grass under the snow on the valley floor, they're ready to search elsewhere. perhaps the wind has blown the snow off the top of the ridge and exposed something to eat. perhaps not. the lead bison is all but stuck. it looks like she could use a better idea. but no one seems to have one.

the fox, too, is out hunting for something to eat. in a place so vast and empty, he looks too small to be out here all alone. but today, the fox has company. the fox can't seem to believe his eyes, and races down to confirm this strange sighting --

a human... in winter! in the upper geyser basin, old faithful erupts on schedule.

winter has no effect on its deep, internal cycle. but the surface world has been feeling the season, the tilting of the north away from the sun. december 21st, and yellowstone's smoke signals rise to an early sunset. it's the shortest day of the year. the earth has reached a turning point in its orbit, and appears to pause, while high overhead, a great celestial battle has begun. every year, the tug of war is the same -- day versus night,

sun versus moon, light versus dark. tonight, darkness will win one last time. tonight is the winter solstice, the longest night of the year. by dawn, the battle is over. light has won the day.

yellowstone is spinning back toward the sun. though officially, winter has just begun, its days are already numbered. the fox is trying to sleep in, but it's no use. the neighbors are celebrating the dawn. once he's up, he's bound to be hungry.

but there's no breakfast hiding under the snow. he sets off along the bank of the yellowstone river, just upstream of the mighty falls. in the shadow of the falls, a lone otter is finishing a fish.

[ calls ] it's the injured youngster, still nursing his foot. he calls, but no one answers. his family is nowhere in sight. another small figure has been watching. a coyote has a slim chance of actually taking an otter. his best hope is to scare one into dropping a fish. at this time of year, his finest meals come from someone else's table. no otter, no fish. the coyote must move on.

something in the distance catches his attention. wolves. in yellowstone, wolves are a coyote's worst enemy. but he's in luck. the wolves are hunting, and if they succeed, there will be a carcass, and a feast. from half a mile away, the coyote follows every move.

he needs the wolves to win this battle. but the bison mount a strong defense. all the coyote can do is watch and wait. a snowfall muffles the voices of trumpeter swans. [ calls ] this is the first winter for these cygnets. by next christmas, they'll be as white as the falling snow. [ calls ]

a stillness settles over everything. murphy: the reason i keep coming back in the winter -- it's an opportunity to come out and see this, this... country that's quiet. it's sort of like -- it's my church, it's my cathedral, it's what i like here. narrator: high up in her den, the grizzly is alone, but that's about to change.

deep in hibernation, her body is preparing for one more amazing feat. last summer, she mated. she entered her den as a mother-to-be. soon, she will give birth. a quiet darkness winds its way through the forests of yellowstone. and it's in this cold, winter darkness that the lights of christmas burn so bright. ♪ oh tidings of comfort and joy ♪ ♪ comfort and joy ♪ oh tidings of comfort and joy ♪

♪ we wish you a merry christmas ♪ ♪ we wish you a merry christmas ♪ ♪ we wish you a merry christmas ♪ ♪ and a happy new year ♪ we wish you a merry christmas ♪ ♪ we wish you a merry christmas ♪ ♪ we wish you a merry christmas ♪ ♪ and a happy new year [ cheers and applause ] narrator: inside the snow lodge, visitors share the magic of christmas eve. but this year, they've left their homes and much of the 21st century far behind. ♪ sleep in heavenly ♪ peace ♪ sleep in heavenly peace narrator: outside in the night,

yellowstone remains much as it was that first christmas some 2,000 years ago. christmas day sparkles in the cold. it shines on a once and forever wilderness, a miracle in the modern world.

the fox is up early this morning. a hawk has already been hunting. and freshly printed in the snow is the signature of a trumpeter swan. devoted visitors gather early in lamar valley.

they're hoping to see wolves on christmas day. i'm just really hooked on wolves. i think they're great-looking animals. when you are wolf-watching and you're not seeing any wolves, you're seeing bald eagles, golden eagles, peregrine falcons, coyotes, badgers, everybody else is here -- and you always get to see something. and if you're not even seeing animals, look how gorgeous it is, you know, just the scenery alone. here come the -- look, look, look. we got a dog! hold on, something's coming in. what is it, a coyote? no, it's -- unh-unh, no. it's a wolf! we got a wolf! we have a wolf. oh, my -- all righty! well, see? that's what it's all about! that, that moment. there he is, it's a black -- nice.

narrator: a young black wolf and her parents are attempting to cross soda butte creek, but winter presents challenges even for them. they are wise to be cautious. there'll be no river crossing today.

down along the yellowstone river, the otter family has come together. even the lame youngster is in their midst. it's a christmas reunion, and today, they have an appreciative audience. man: do they normally stay in families? man: quite often, we see three of them together in this stretch of river, and today's actually been

the first time this winter that i've seen four at one time. quite often, we see eagles somewhere around the otters, or coyotes somewhere around the otters. actually, right there! there's a bald eagle right in that tree. there's a bald eagle right there, look at that. [ laughing ] good spot. narrator: this is yellowstone's special gift -- to experience for ourselves the world that used to be, to enter the same fierce, wild place john colter did two hundred years ago, and still find it so alive. [ howling ]

[ wolf barking in distance ] murphy: anybody who's sat out on a hillside in the winter, when it's so still, and heard a wolf -- there's no price tag you can put on it. they'd empty their pockets to hear it again. [ wolf howling in distance ] murphy: yellowstone has given me a lot of gifts. and it's given the entire world a lot of gifts. it's done that for over 130 years. it's an example for what's possible, it's an example for what was.

and we can improve on some things, but we cannot improve on this. we can't improve on this at all. narrator: just outside the park, time picks up its usual pace. man: happy new year! narrator: down in jackson hole, christmas ends as it began, with the magic of lights dancing in the dark.

new year's eve welcomes in the future, a future in yellowstone, full of the promise of the past. two little grizzly bears have been born into the new year. only 4 pounds each, they're tiny next to their 400-pound mother. she is still in hibernation, but the cubs are busy playing. they're preparing for a world their ancestors ruled,

and that still belongs to them. in spring, when they are ready, yellowstone will be waiting. and, white and shining like a beacon, it will be waiting for us as well to celebrate the wilderness next christmas... and all the christmases to come.

the polar bear, built to survive the farthest reaches of the arctic. but pressing north, a fierce rival -- the grizzly. previously, these bears would rarely meet. but that is changing. the arctic is melting. is the grizzly bear poised to claim the arctic, or will the polar bear hang on? now you can watch "nature" online. go to pbs.org to screen complete episodes from this season and seasons past. visit "nature" online for production updates from the field. well, here we are on the alaska coast. go behind the scenes with our filmmakers. we also used a borescope lens, and that allowed us to put the lens right into a flower. and get connected with "nature's" online community. all at pbs.org.

"nature" is made possible in part by... leave it untouched inspby your presence.re.. capture its image and preserve it forever. canon -- living and working together to appreciate today and care for tomorrow. the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. plus $4.95 shipping. to order, call 1-800-336-1917.

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