Category
📺
TVTranscript
00:00Transcribed by —
00:30Transcribed by —
01:00Transcribed by —
01:29There can be great rewards.
01:36This is a land of opportunity.
01:45Over a hundred times the size of Great Britain,
01:48North America stretches from just above the equator
01:51almost to the North Pole.
01:54Temperatures can range from 50 degrees Celsius to minus 40.
02:13The coldest wilderness of all lies in the Arctic North.
02:25Here, in Canada's Yukon Territory, winter is brutal.
02:40Many animals have traveled south to avoid the worst of the cold.
02:45For those which stay behind, life becomes very hard indeed.
03:00A Canadian lynx.
03:02No other kind of cat anywhere lives farther north than this one.
03:21The search for food could take him hundreds of miles.
03:25A snowshoe hare.
03:26This could be a chance.
03:27This could be a chance.
03:45A snowshoe hare.
03:51This could be a chance.
03:53A snowshoe hare.
03:54This could be a chance.
04:08He's lost the element of surprise.
04:10And now there's a tangle of branches between him and his prey.
04:15And now there's a tangle of branches between him and his prey.
04:40Missed again.
04:41More of his energy wasted.
04:42Missed again.
04:43More of his energy wasted.
04:56Missed again.
04:57Missed again.
04:58Missed again.
04:59Missed again.
05:00Missed again.
05:01Missed again.
05:02Missed again.
05:03Missed again.
05:04Missed again.
05:05Missed again.
05:06Missed again.
05:07Missed again.
05:08Missed again.
05:09Missed again.
05:10Missed again.
05:11Missed again.
05:12Missed again.
05:13Missed again.
05:14Missed again.
05:15Missed again.
05:16Missed again.
05:17Missed again.
05:18Missed again.
05:19Missed again.
05:20Missed again.
05:21Missed again.
05:22Missed again.
05:23Missed again.
05:24Missed again.
05:25Missed again.
05:26and another failure.
05:45If he doesn't kill soon, he may not survive these winter months.
06:14But in North America, change is never far away.
06:28April and billions of tons of snow and ice are starting to melt, bringing new opportunities.
06:39Much of the water drains southwards.
06:4410,000 creeks join, forming North America's biggest river system.
06:53The meltwaters travel 2,000 miles down the Mississippi, right through the heart of North America.
07:05In the streams of Tennessee, River Chub are getting ready to breed.
07:14This male is busy building a mound of stones in which, if he's lucky, a female will lay
07:27her eggs.
07:36As the river flows faster, the work gets harder.
07:45It's a good start, but rivals are doing the same thing and want some of his pebbles.
07:54It's a good start.
08:03The intruder's seen off, and it's back to business.
08:12The intruder's seen off, and it's back to business.
08:24The intruder's seen off, and it's back to business.
08:41And then, with the last of some 7,000 stones, his nest is complete.
08:50And then, with the last of some 7,000 stones, his nest is complete.
09:11And right on time, here is a female.
09:17But the mound now needs one last feature.
09:27A trench where she can lay her eggs.
09:33And with a gentle shimmy of his body, he nudges her into position.
10:03And she deposits her eggs where they will be safe from both currents and predators.
10:22His work is done.
10:24The eggs will hatch, and then his mound will be slowly dismantled by the current.
10:30So, next year, you'll have to start all over again.
10:40Spring is now well on its way.
10:49North America is wonderfully rich in wildflowers.
10:53There are over 10,000 species of them.
11:00Hummingbirds fly up from the south to feast on the nectar.
11:24Long the North American coast, the tides are the largest in the world.
11:39The fragmented shoreline forces seawater to rush up narrow innets.
11:45And each time the tide retreats, it opens a freshly stocked larder.
12:057,000 square miles of extra coastline is uncovered in the space of just two hours.
12:12A mother black bear is looking for something suitable for her cubs.
12:38This is their first ever trip to the seaside.
12:42In a few hours, the tide will return.
12:59So, they must keep up with mum.
13:09Here's something tasty, crabs.
13:39Meat crabs can give a nasty nip, so it's best to start off with smaller ones.
13:52During spring, three-quarters of the bear's food comes from the beach.
14:00It's a big one.
14:07I'm not sure what it's like.
14:13I'm not sure what it's like.
14:19I'm not sure what it's like.
14:23But now, this family is not alone.
14:41An adult male. He's double her size, and they're in his territory.
14:47The cubs know that call. It's time to head for safety.
15:02Bears have poor eyesight, but their sense of smell is acute,
15:07and the male has detected intruders.
15:17He knows exactly which tree they are in.
15:25If the cubs stay up there, they'll be safe,
15:27but they're losing precious feeding time.
15:36For now, he's content to leave his scent mark.
15:40A warning note for trespassers.
15:50The family moves on.
15:55For the cubs, lunch today will have to be a takeaway.
15:59The tide comes in.
16:15And within minutes, feeding time is over for another day.
16:19As the continent warms, on a few special nights,
16:32when the temperature is just right,
16:36the forests of North America put on a show.
16:39Male fireflies are taking to the air.
16:59These insects are not, in fact, flies.
17:01They're a kind of beetle.
17:03The light produced by the males is the most energy efficient on Earth.
17:17Some species synchronize their flashes
17:20to increase the visibility of the message.
17:33If a female sees something she likes,
17:36she returns the signal.
17:48It looks as if the message is working.
18:03But the forest is booby-trapped
18:07by orb-weaver spiders.
18:10The firefly continues to glow, even in death.
18:32The firefly continues to glow, even in death.
18:41Other males see the flashes, but not the dangers.
19:06The spider's larder is filling up.
19:10But for every firefly that gets caught, thousands avoid the traps.
19:13But for every firefly that gets caught, thousands avoid the traps.
19:40And this male is lucky.
19:45He's found a mate.
19:55And over the course of the night, millions will pair up.
20:00There are over 150 different species of fireflies in North America,
20:21and each has its own flash code.
20:23Flash code.
20:39Once they're mated, the females deposit their eggs in the ground.
20:44And for those that didn't find a mate,
20:46their one chance has come and gone.
20:50Little rain reaches the heart of the continent.
20:56Little rain reaches the heart of the continent.
21:06For over a million square miles, there's not a tree in sight.
21:11Little rain has come and become and their nest.
21:12Little rain comes and teaches the most of them.
21:14But just the rain of the ocean keeps moving.
21:15Little rain reaches the heart of the continent.
21:18For over a million square miles, there's not a tree in sight.
21:23Many of those living here, spend much of their time underground.
21:41The presence of the city is a place where the city is located.
21:45The city is a place where the city is located.
21:48The city is a place where the city is located.
21:52A prairie dog, a kind of large burrowing squirrel.
22:00Sentinels keep watch, ready to warn others of any danger.
22:07And at this time of year is a new generation to protect.
22:13This mother has six pups.
22:22The youngsters constantly beg for food.
22:27After all, the pups aren't great at sharing.
22:30But the prairie dogs don't have the prairies to themselves.
22:43An American badger.
22:46The pups have never seen one before.
22:48And badgers eat pups.
22:58A burrowing owl.
23:02It also knows that badgers are dangerous.
23:04It too has young and does not want the badger anywhere near them.
23:17Eventually, the badger gives up.
23:30Eventually, the badger gives up.
23:31He sets off to look elsewhere.
23:48If he can find a place where the grass is higher than he is,
23:52he will have a better chance.
23:54Or i'll have a better chance.
23:55Let's get started.
23:56The mother sounds the alarm.
24:26Adults know the danger all too well.
24:44Four pups make it to safety below, but their mother dare not wait above ground any longer.
24:54The mother sounds the same way.
25:04The mother sounds the same way.
25:10Half of all prairie dog pups don't survive to adulthood.
25:28Predators are not the only problem faced by animals living on these great plains.
25:40Warm air sweeps up from the Gulf of Mexico and across the open prairies.
25:56And here, with no mountains to block it, it meets the frigid air from the Arctic.
26:08The results are spectacular.
26:22As the air currents mix and swirl, they build into one of nature's most fearsome forces.
26:30Tornadoes.
26:40These twisters spin at speeds of up to 300 miles an hour.
26:44The world's fastest wind.
26:56There's a thousand tornadoes touched down here every year.
27:00The searous atmosphere that we can use.
27:08First of all, is that fight is intense.
27:14The enemy is además of the enemy's most imperfection.
27:18It has a day to be impossible with the enemy's most飾lands.
27:24These drenching summer storms are prevented from spreading westwards by the Rocky Mountains.
27:42Some peaks are over four kilometers high, so beyond them to the west, much of the land remains parched.
27:54The great American deserts cover over a million square miles.
28:09Here, roasted by the sun and blasted by the wind, the rocks disintegrate and mountains, particle by particle, are reduced to sand.
28:24These pillars are all that remain of a plateau where dinosaurs once roamed.
28:44Few animals can now survive here.
28:47In summer, as in all deserts, the enemy is heat, and it returns every day.
29:03At seven in the morning, the temperature is already 25 degrees Celsius.
29:14The clock is ticking for one unusual descendant of the dinosaurs.
29:20A roadrunner, found only in the deserts of North America, built for a life on the ground.
29:27A roadrunner found only in the deserts of North America, built for a life on the ground.
29:35A roadrunner found only in the deserts of North America, built for a life on the ground.
29:49A roadrunner found only in the deserts of North America, built for a life on the ground.
29:53He can run at over 20 miles an hour.
29:58But the prey he seeks are one step ahead.
30:23The roadrunner's challenge is picking the right target.
30:26The roadrunner's challenge is picking the right target.
30:42A killer monster.
30:44Too big.
30:46By mid-morning, it will be 40 degrees Celsius.
31:00Even the smallest lizards will soon head for cover.
31:16A centipede.
31:21Slim pickings for the morning's work.
31:33Hunting should get easier, and prey will stay out longer once the summer's peak begins to fade.
31:46.
31:56On the east coast, summer is coming to an end.
32:01Cold currents are sweeping along the coast of Florida.
32:05And with them come grey mullet, on their migration to their spawning grounds in the south.
32:26Millions of them, unpacked so tightly, they stain the water like an oil slick.
32:33Few people on the beach are even aware of them.
32:38The mullet keep as close to the shore as possible, for in deeper water there are predators.
32:56Close to the beach, they have to keep clear of human swimmers.
33:01But now hunters from the open ocean have detected them.
33:18Tarpawn, over two meters long, and weighing over a hundred kilograms.
33:23To get close to the mullet in the shallows, the tarpawn turn on their sides.
33:40Now the mullet can't see their shining silver flanks until it's too late.
33:44It's too late.
33:53And feasting begins.
33:54Black tipped shark arrive.
33:55Pelicans join in.
33:56Black tipped shark arrive.
33:57Pelicans join in.
33:59Black tipped shark.
34:01oss欸
34:24But these attacks have little effect on the immense shoals.
34:48The mullet outnumber their enemies by 10,000 to 1.
34:54So the great procession travels on into the northern Atlantic Ocean where at last they
35:01will be able to spawn in safety.
35:08Autumn arrives in North America.
35:14No mountain range spans the continent from east to west, so there is nothing to stop cold
35:19air from the Arctic sweeping down unhindered as far south as Louisiana.
35:38Autumn brings color to the southern swamps.
35:45Here it has been hot and humid for most of the year, and now these subzero temperatures
36:02are something of a trial for the local inhabitants.
36:19An American alligator.
36:39The alligator reacts to the chill by slowing its heart rate to barely one beat per minute.
36:47It's a kind of energy-saving winter sleep.
36:55But other creatures don't have this ability.
36:59The largest inhabitants of the swamp.
37:04A relative of the elephant.
37:10A manatee.
37:14A female provides milk for her calf from a teat behind her flipper.
37:25She might be able to survive the chill, but her calf cannot.
37:33So, every autumn, they need to find warmer waters.
37:50They have a long journey ahead.
37:52It could be hundreds of miles.
37:54And she is not alone.
38:13And she is not alone.
38:18The warm waters they need to survive come from an unusual source.
38:38An immense underground river flows through subterranean channels in Florida's rocks.
38:46In places, it comes to the surface, creating over a thousand springs.
38:57Now in winter, these springs are 10 degrees warmer than the surrounding waters.
39:06So manatees come here every year from far and wide.
39:14And here they can relax.
39:29They can get their backs scrubbed.
39:36And they socialize.
39:41No one is in much of a hurry.
39:52And young manatees have a chance to meet some surprising neighbors.
40:01In summer, playing with an alligator might be a dangerous game.
40:08But now, at any rate, the giant reptiles are still too chilled to react with any bigger.
40:26Without these warm pools, fewer Florida's manatees would be able to survive the winter.
40:46But the water waves here are now very popular with people, too.
40:51And many manatees carry scars inflicted by the propellers of boats.
40:58Her calf has already had its first scrape.
41:03Every year, more than 100 manatees die from human causes.
41:17As the human population of Florida grows, so wildlife is coming under increasing pressure.
41:26Across North America, a million acres of wilderness are lost every decade.
41:48But it is in the far north of the continent that human beings are affecting wildlife most critically.
41:57Canada is warming faster than any other country on Earth.
42:03Canada is warming faster than any other country on Earth.
42:16Polar bears have always relied on sea ice for their hunting.
42:22But summers are now getting longer and hotter.
42:32For most polar bears, this is a time of starvation.
42:48On the shores of Hudson Bay, some bears are finding a new source of food.
43:03They're all looking for the same thing, and they have their own ways of catching it.
43:09First, they must find the right rock.
43:31Now, they must wait.
43:36The tide comes in, bringing with it other northern giants.
43:48The tide comes in, bringing with it other northern giants.
43:53Beluga whales.
44:10Close to the shore, their calves should be safe for the ocean-going predators such as orca.
44:21Over 3,000 whales have gathered here.
44:26A young male makes his move.
44:44Polar bears are skilled marine hunters.
44:47And beluga are slow swimmers.
44:49Polar bears are skilled marine hunters.
44:54And beluga are slow swimmers.
44:59And beluga are slow swimmers.
45:02And beluga are slow swimmers.
45:06Polar bears are slow swimmers.
45:11The game is at the same time.
45:14Polar bears are slow swimmers.
45:16And the tide begins to get out of all the waves.
45:18The tide begins to burst.
45:20And the tide begins to sting.
45:21The tide begins to pop up to the shore.
45:23As long as a whale can keep an eye on a hunting bear, it should be safe.
45:53This young bear is still learning.
46:12More experienced bears know to be patient.
46:23Success will depend on split-second timing.
46:33To be continued...
47:01A bite at the back of the head, and the kill is swift.
47:22This extraordinary behaviour has only been reported here, in this remote corner of North
47:37America, and only the last few years.
47:51This one small group of bears has found an ingenious way of surviving the lean summer months.
48:10But for others, it is not so easy.
48:19We continue to transform our planet, and the seasons are becoming less predictable.
48:29Will the wildlife of North America be able to adapt?
48:34Not only on this continent known for its change, but in a rapidly changing world.
48:41The North America crew heard reports of a rarely seen polar bear hunting behaviour.
49:02To film it, they set out on a small boat to navigate the far corners of Canada's Hudson Bay.
49:19But the weather here on the Arctic Circle can be unpredictable.
49:29We're out in the middle of Hudson Bay, and we have a thunderstorm approaching.
49:34The thing you don't want with a thunderstorm is a metal boat and a big metal crane.
49:41Hundreds of miles from help, there's no chance of rescue here.
49:45So the crew head for safety.
49:47The 30k and I'm gusting up to 50 or 60, so it's going to get a little nasty.
50:16On land, they'll be safe from the storm, but they need to be armed.
50:23Polar bears have little fear of humans, and at this time of the year, most are hungry.
50:31With the bears at a safe distance, there's time for a quick moment to celebrate cameraman John's 40th birthday.
50:43We've come to what is probably one of the windiest shoots I've ever done in my life.
50:47This is the first time I've had a birthday on the beach.
50:50Are you kidding? Yeah.
50:52Yeah, and what a beach it is.
50:54At the first sign of calm weather, the crew head back out to look for a key part of the story.
51:02Beluga whales.
51:15With frigid waters and strong currents, a thin rope will be cameraman Bertie's only lifeline.
51:21Bertie can hear the belugas, but he can't see them.
51:40To communicate, the whales sing to each other through the murky water.
51:47So with this underwater microphone, we're going to listen to what these beluga whales are singing for Bertie.
51:55Listening to their calls gives the crew an idea.
52:05Bertie tries enticing the belugas closer with some tunes of his own.
52:12Despite some questionable singing, it seems to be working.
52:34Once reeled in, he shares the secret.
52:37The moment I started singing Adele, they just went crazy.
52:45It's the chorus. It's what gets them. Every time.
52:50With their boat the only feature for miles, it's not just beluga that come to check them out.
52:58He's a young guy, really curious.
53:01That's about as close as you can get to a polar bear.
53:07This bear is pulling our anchor off the bottom and we're drifting because he keeps pulling it up.
53:25Okay, leave that anchor alone. Leave it.
53:28With all eyes on the bear, the crew suddenly realise they have a bigger problem to deal with.
53:38Their boat has hit a rock.
53:43Do you know where exactly the rock is?
53:45Strong currents risk tipping the boat and putting the crew in serious danger.
53:54We're up on top of it, I think.
54:08The team doesn't have long before the falling tide will leave them stranded on the rock.
54:13Is it moving or is it just swinging?
54:15Okay, push your end, push.
54:21Okay, we're off.
54:22We're off.
54:24A narrow escape.
54:27Like all film crews, we kept wanting more and more.
54:30Eventually the boat got high-centered on a rock.
54:33I didn't think about bears until I was back on the boat.
54:37That was a bear in the water.
54:38Yeah, oh yeah, there were a couple right around us.
54:40Yeah.
54:48But with time running out, there's little sign of the bear's unique hunting strategy.
54:53It's a waiting game for both the bears and the crew.
55:08Bear, bear, bear!
55:09Straight off the front.
55:10Finally, a big male in a promising position.
55:18This is just the situation they've been looking for.
55:22With one camera on the boat and one in the air,
55:27the crew is hoping to cover the action from all angles.
55:34It's just waiting for the right one in the right spot.
55:43He's got one.
55:44He's got one.
55:45Let's get the anchor up.
55:46Anchor up.
55:48He's got it.
55:51He's got it on the back of the head.
55:57Right.
55:58He's got him by the tail now.
56:02For the team, witnessing this life and death struggle is hard.
56:06It's kind of shocking when it just happens in front of you like that.
56:14It's amazing how powerful the bear is.
56:15It's just breath.
56:16An animal is designed to be in the water and be powerful and the bear just throws it around.
56:20Yeah.
56:22To see an animal lose its life is upsetting and the crew are left with mixed feelings.
56:30We've really connected with these belugas, so it's sad to see them die, but that was a really spectacular bit of nature right there.
56:39This footage adds to our understanding of these ingenious animals.
56:44In a changing world, one small group of polar bears has come up with a remarkable strategy for survival.
57:00Next time, the continent where wildlife puts on the greatest show on earth.
57:15Africa.
57:16And that will sadly be the final episode.
57:34But you can pre-order the Seven Worlds One Planet DVD now.
57:38And find out about a cracking playlist inspired by this stunning series.
57:42Download BBC Sounds to be inspired yourselves.
57:45Here later, the Martian invasion continues.
57:48Get a cushion ready to hide behind for the final part of the War of the Worlds at 9.