WEBVTT 00:00:12.929 --> 00:00:15.015 Welcome to North America. 00:00:21.312 --> 00:00:23.815 The most diverse continent on Earth. 00:00:27.610 --> 00:00:31.823 The only place where you can find every landscape from polar ice cap, 00:00:33.950 --> 00:00:37.704 to baking desert, and everything in between. 00:00:40.040 --> 00:00:44.627 Whatever the neighborhood, there is a hero who can make it a home. 00:00:51.426 --> 00:00:56.723 Smart, tough, brave, you name it. 00:00:57.390 --> 00:00:59.350 They all have what it takes to thrive 00:01:00.935 --> 00:01:04.522 in the wildest, most beautiful continent on Earth. 00:01:41.267 --> 00:01:43.728 At the very center of North America, 00:01:44.687 --> 00:01:46.272 lies the Heartland. 00:01:48.108 --> 00:01:51.121 A million square miles of prairies, 00:01:51.145 --> 00:01:54.072 rolling hills, and woodland 00:01:54.781 --> 00:01:56.908 from Texas to Canada. 00:01:59.160 --> 00:02:02.831 It's a beautiful land, but you've got to be prepared 00:02:03.832 --> 00:02:06.126 for all seasons in a day. 00:02:12.257 --> 00:02:17.762 This is the most changeable and extreme place on Earth. 00:02:31.734 --> 00:02:33.736 Deep in the forests of the Heartland, 00:02:35.488 --> 00:02:38.658 one of America's top predators is stirring. 00:02:43.621 --> 00:02:46.666 A hunter of near legendary status. 00:02:50.587 --> 00:02:51.588 A wolf pup. 00:02:54.507 --> 00:02:58.344 Okay, not a legend yet, but he's working on it. 00:03:02.640 --> 00:03:03.975 Mom's gone off hunting, 00:03:05.852 --> 00:03:07.812 and at every entrance of the den, 00:03:09.564 --> 00:03:11.065 there's a pup calling for her. 00:03:28.750 --> 00:03:30.376 They're definitely missing mom. 00:03:38.134 --> 00:03:40.261 But her absence is an opportunity 00:03:41.596 --> 00:03:43.014 to go exploring. 00:04:13.753 --> 00:04:15.880 The world outside is fun. 00:04:16.923 --> 00:04:17.924 Mostly. 00:04:22.303 --> 00:04:24.597 This play builds their strength and agility. 00:04:25.139 --> 00:04:27.267 And establishes their rank in the pack. 00:04:29.394 --> 00:04:32.313 A bite to the tail shows who's boss. 00:04:36.276 --> 00:04:38.027 In just five months' time, 00:04:38.403 --> 00:04:42.115 these guys will be old enough to join the adults on the hunt, 00:04:44.284 --> 00:04:46.577 where they'll have to face much bigger dangers... 00:04:50.081 --> 00:04:51.332 ...than a gust of wind. 00:04:59.882 --> 00:05:03.845 The ever-changing Heartland is a hard place to raise a family. 00:05:06.514 --> 00:05:11.519 Adult wolves must catch up to 50 percent more prey when they've got pups to feed. 00:05:15.481 --> 00:05:18.776 Bison, the symbol of the Heartland, 00:05:19.694 --> 00:05:20.987 are their biggest prize. 00:05:32.498 --> 00:05:33.583 A newborn. 00:05:41.716 --> 00:05:46.262 A potential target for a female wolf with hungry pups back in the den. 00:05:52.268 --> 00:05:53.811 She could take down the calf 00:05:55.271 --> 00:05:57.357 if she can get past the bodyguard. 00:06:13.706 --> 00:06:15.958 Two mothers, eye-to-eye. 00:06:24.300 --> 00:06:25.385 No contest. 00:06:32.266 --> 00:06:35.770 She doesn't have the weapons to tackle a healthy adult bison alone. 00:06:38.106 --> 00:06:40.149 She heads off to rejoin her pack. 00:06:48.074 --> 00:06:51.661 Working together, they track down a group of elk. 00:06:53.287 --> 00:06:56.541 Smaller than bison, but faster. 00:07:03.464 --> 00:07:05.383 The pack has a plan. 00:07:07.343 --> 00:07:09.387 Two wolves get the elk running... 00:07:11.764 --> 00:07:15.017 straight towards a catcher who's waiting in their path. 00:07:31.659 --> 00:07:32.910 No luck today. 00:07:34.370 --> 00:07:36.497 These elk are too strong and healthy. 00:07:37.999 --> 00:07:39.917 The wolves need to bide their time, 00:07:40.084 --> 00:07:42.503 and wait for conditions to change in their favor. 00:07:47.592 --> 00:07:49.802 Those conditions can change in a heartbeat. 00:07:53.764 --> 00:07:55.308 This South Dakota landscape 00:07:57.268 --> 00:08:00.438 is evidence of just how extreme things can get. 00:08:03.107 --> 00:08:07.820 Every year, violent rains and flash floods carve away the ground here. 00:08:10.156 --> 00:08:13.784 The result is a jagged maze so hard to travel through... 00:08:15.411 --> 00:08:19.332 it was named The Badlands by the Lakota people. 00:08:23.878 --> 00:08:26.380 But right alongside the rocky ridges, 00:08:27.048 --> 00:08:29.675 one of America's largest grasslands. 00:08:32.637 --> 00:08:35.097 A perfect home for grass-eaters. 00:08:38.059 --> 00:08:39.185 Prairie dogs. 00:08:42.897 --> 00:08:45.733 These burrow-dwellers live in a peaceful town 00:08:47.235 --> 00:08:48.945 with well-tended lawns. 00:08:53.157 --> 00:08:57.286 But the peace is about to be disturbed. 00:09:07.129 --> 00:09:08.506 This burrowing owl 00:09:09.590 --> 00:09:11.050 and his partner in crime 00:09:12.969 --> 00:09:14.637 have just flown in from Texas. 00:09:17.056 --> 00:09:18.182 They're not coming to hunt... 00:09:21.561 --> 00:09:22.603 but to steal. 00:09:25.648 --> 00:09:29.151 They wanna take over a prairie dog burrow to raise a family in. 00:09:32.989 --> 00:09:35.449 The homeowner's not happy about the invasion. 00:09:39.203 --> 00:09:41.163 But this burrow... 00:09:41.330 --> 00:09:42.832 ...ain't big enough for the both of them. 00:09:48.838 --> 00:09:50.590 The owls are here to stay. 00:10:01.851 --> 00:10:04.687 Their newly-acquired home is ten feet deep, 00:10:05.771 --> 00:10:08.941 solidly built, and it needs to be. 00:10:10.192 --> 00:10:12.486 The owls will need their burrow's protection 00:10:12.653 --> 00:10:16.282 if they're to raise a family through the wild challenges that lie ahead. 00:10:26.917 --> 00:10:30.755 Springtime is migration time across the Heartland. 00:10:38.929 --> 00:10:41.849 Snow geese are flying from the Southern US 00:10:42.099 --> 00:10:44.560 to their summer breeding grounds in the Arctic. 00:10:46.979 --> 00:10:49.649 They follow North America's greatest rivers, 00:10:50.024 --> 00:10:52.652 the Mississippi and Missouri. 00:10:55.446 --> 00:10:58.157 Their journey is 2,000 miles. 00:11:06.499 --> 00:11:09.043 So, sometimes, you gotta take a break. 00:11:20.971 --> 00:11:22.431 Over one million geese 00:11:22.848 --> 00:11:27.144 rest up at this Missouri lake on their migrations every year. 00:11:32.149 --> 00:11:34.193 It's a great American spectacle. 00:11:38.614 --> 00:11:39.990 And it's being watched... 00:11:41.701 --> 00:11:43.202 by an American icon. 00:11:45.871 --> 00:11:47.081 Bald eagles. 00:11:48.082 --> 00:11:50.459 Some on their own annual migration. 00:11:53.754 --> 00:11:55.631 Up to 800 birds... 00:12:00.052 --> 00:12:03.097 adults and juveniles, 00:12:05.099 --> 00:12:06.809 looking for an opening. 00:12:10.688 --> 00:12:12.940 The geese are alert to the danger. 00:12:17.361 --> 00:12:20.489 By taking off together, they blindside the eagles. 00:12:27.079 --> 00:12:29.331 The predators can't pick out a single target 00:12:31.333 --> 00:12:33.586 in this confusing swirl of wings. 00:12:42.219 --> 00:12:46.056 A juvenile eagle spots an isolated goose. 00:12:47.558 --> 00:12:48.851 But the goose escapes. 00:13:01.155 --> 00:13:04.825 By diving underwater, he dodges the deadly talons. 00:13:06.327 --> 00:13:07.828 Round one to the geese. 00:13:17.630 --> 00:13:21.675 But the adult eagles know that it pays to be patient. 00:13:25.471 --> 00:13:26.555 In the Heartland, 00:13:26.680 --> 00:13:29.266 change is always just around the corner. 00:13:35.314 --> 00:13:36.774 The winds shift. 00:13:38.359 --> 00:13:41.987 Cold air is now blowing all the way from the Arctic. 00:13:43.364 --> 00:13:47.785 From Texas to Canada, there are no mountains to block the wind. 00:13:49.745 --> 00:13:53.624 The temperature can plummet by over 50 degrees in a day. 00:13:57.753 --> 00:14:00.923 The fastest rate of change on the planet. 00:14:04.969 --> 00:14:06.929 As the waterways freeze... 00:14:09.849 --> 00:14:11.100 ...the odds change. 00:14:14.645 --> 00:14:15.688 The geese 00:14:16.856 --> 00:14:18.274 lose their escape route. 00:14:21.360 --> 00:14:23.195 And some of the exhausted travelers 00:14:24.697 --> 00:14:26.532 fall prey to the bitter cold. 00:14:32.621 --> 00:14:37.418 The sudden extreme freeze-up does the eagles' hunting for them. 00:14:40.254 --> 00:14:42.965 Their challenge now isn't making the catch... 00:14:45.551 --> 00:14:46.677 it's keeping it. 00:14:52.933 --> 00:14:56.270 Adults usually get the better of the brown-headed juveniles... 00:14:59.648 --> 00:15:02.318 though the youngsters still try their luck. 00:15:24.089 --> 00:15:26.091 The geese that survive the cold 00:15:26.300 --> 00:15:28.928 continue their journey towards their Arctic breeding grounds. 00:15:32.932 --> 00:15:34.683 The party's over for the eagles. 00:15:40.356 --> 00:15:42.441 But they took their chance when it came, 00:15:43.525 --> 00:15:44.652 as you have to 00:15:45.319 --> 00:15:47.071 in the ever-changing Heartland. 00:15:51.575 --> 00:15:54.885 Out on the plains, the cold snap brings 00:15:54.909 --> 00:15:57.665 three feet of snow in 24 hours. 00:16:11.345 --> 00:16:13.806 Bison bulldoze through the drifts. 00:16:21.397 --> 00:16:23.649 Others barely break the surface. 00:16:32.032 --> 00:16:33.075 A red fox. 00:16:39.248 --> 00:16:41.166 She's hunting for buried treasure. 00:16:45.212 --> 00:16:49.216 Voles, hiding in tunnels beneath the snow. 00:16:51.010 --> 00:16:52.845 It won't be easy today, though. 00:16:54.638 --> 00:16:58.726 The howling wind and swirling snow are scrambling her senses. 00:17:06.233 --> 00:17:11.780 Her massive satellite ears can normally hear a vole from 100 feet away. 00:17:14.742 --> 00:17:19.329 Tilting her head from side to side, she tries to pinpoint the target 00:17:19.580 --> 00:17:21.206 using sound alone. 00:17:39.933 --> 00:17:40.934 Nope. 00:18:00.871 --> 00:18:01.914 No luck. 00:18:02.873 --> 00:18:05.084 But she won't let the weather defeat her. 00:18:06.376 --> 00:18:07.920 Time for Plan B. 00:18:10.047 --> 00:18:11.381 That's B for "bison". 00:18:18.138 --> 00:18:22.935 As they dig for grass, they destroy the voles' tunnels. 00:18:28.440 --> 00:18:30.192 The rebuilding work is noisy... 00:18:32.694 --> 00:18:34.530 if you've got ears like a fox. 00:18:44.206 --> 00:18:47.459 Now, she can get a proper fix on her target. 00:19:06.436 --> 00:19:07.688 Dinner at last. 00:19:27.166 --> 00:19:28.500 A little guile... 00:19:30.169 --> 00:19:31.211 goes a long way... 00:19:32.504 --> 00:19:35.090 in this land of extremes. 00:19:41.054 --> 00:19:43.974 And few places are more extreme than here, 00:19:44.183 --> 00:19:47.019 where the Heartland meets the Rocky Mountains. 00:19:50.606 --> 00:19:53.317 America's oldest national park, 00:19:54.568 --> 00:19:55.569 Yellowstone. 00:19:56.737 --> 00:20:00.699 Up to 400 inches of snow fall here every year. 00:20:05.287 --> 00:20:09.041 For these two-year-old grizzly bears just out of hibernation, 00:20:09.791 --> 00:20:13.712 this late spring snowfall is a chance for some fun. 00:20:35.025 --> 00:20:37.569 But for anyone who's had enough wintry conditions, 00:20:38.737 --> 00:20:42.991 there's one place here where you can always find warmth. 00:20:50.415 --> 00:20:52.626 Yellowstone's geyser basin. 00:20:59.007 --> 00:21:03.428 A supervolcano beneath heats underground water to boiling point. 00:21:07.349 --> 00:21:09.977 The scalding water erupts in geysers... 00:21:11.645 --> 00:21:13.647 up to 300 feet high, 00:21:14.273 --> 00:21:15.524 the highest on Earth. 00:21:23.991 --> 00:21:25.784 Bison gather here for warmth... 00:21:30.038 --> 00:21:31.748 ...but they can't get too relaxed. 00:21:33.583 --> 00:21:36.420 Yellowstone is the only place in the USA 00:21:37.546 --> 00:21:39.673 where they still come face-to-face... 00:21:41.425 --> 00:21:42.801 ...with their ancient enemy. 00:21:49.266 --> 00:21:52.144 Our wolf pack, at 30-strong, 00:21:52.394 --> 00:21:55.689 is one of the biggest ever seen in North America. 00:22:07.617 --> 00:22:12.080 Wolves were reintroduced to Yellowstone in 1995. 00:22:13.749 --> 00:22:18.628 They soon learned that bison gather near the hot springs during cold weather. 00:22:33.769 --> 00:22:36.438 The alpha wolf gets their prey moving. 00:22:38.815 --> 00:22:42.444 He chases them away from the hot springs into deeper snow. 00:22:47.199 --> 00:22:49.618 The wolves are playing to their strength. 00:22:50.118 --> 00:22:53.080 They can cover up to 100 miles a day. 00:22:56.666 --> 00:22:59.294 Every step saps the bison's energy. 00:23:06.885 --> 00:23:09.137 The wolves are constantly on their shoulder. 00:23:19.856 --> 00:23:24.569 A massive 2,000-pound bull is guarding the rear of the herd. 00:23:35.914 --> 00:23:40.669 But some wolves get past, chasing the smaller cows. 00:23:51.638 --> 00:23:52.931 The pack's strategy, 00:23:53.598 --> 00:23:55.392 divide and conquer. 00:24:09.698 --> 00:24:11.408 In the frenzied chase, 00:24:12.701 --> 00:24:15.745 one old cow gets left behind. 00:24:21.710 --> 00:24:23.545 And just one wolf. 00:24:29.217 --> 00:24:31.511 The cow is too exhausted to run. 00:24:33.680 --> 00:24:36.057 But she's still ten times the wolf's weight, 00:24:36.266 --> 00:24:39.478 and one strike of her horns could kill him. 00:24:46.443 --> 00:24:49.196 It typically takes at least nine wolves 00:24:49.279 --> 00:24:51.072 to bring down a single bison. 00:25:03.335 --> 00:25:05.295 The rest of the pack is coming to help. 00:25:16.264 --> 00:25:19.100 This old female's race is run. 00:25:25.065 --> 00:25:28.860 By taking out animals that are too weak to cope with the extremes, 00:25:29.027 --> 00:25:33.031 the Yellowstone wolves help to keep the bison herds strong. 00:25:36.493 --> 00:25:40.080 It's a story as old as the Heartland itself. 00:25:46.753 --> 00:25:48.588 A shift to winds from the south... 00:25:53.385 --> 00:25:56.888 and temperatures rise just as quickly as they fell. 00:25:59.849 --> 00:26:02.686 The cold releases its grip. 00:26:07.857 --> 00:26:10.777 And the great rivers that drain half our continent 00:26:11.319 --> 00:26:12.362 thaw out. 00:26:14.281 --> 00:26:16.449 On the US-Canadian border, 00:26:16.741 --> 00:26:21.079 meltwater feeds one of the greatest wonders of the natural world. 00:26:29.379 --> 00:26:31.464 This is the Niagara River. 00:26:40.557 --> 00:26:43.351 And these are the Niagara Falls. 00:27:04.664 --> 00:27:07.000 Over 3,000 tons of water 00:27:07.876 --> 00:27:11.463 plummet over the edge every second. 00:27:16.509 --> 00:27:18.762 Over 100,000 gulls, 00:27:19.179 --> 00:27:21.222 one of the biggest gatherings in the world, 00:27:21.598 --> 00:27:26.436 come here to catch fish stunned by the 200-foot drop. 00:27:51.419 --> 00:27:54.964 The most daredevil birds head above the Falls... 00:27:57.258 --> 00:27:58.426 catching their fish 00:27:59.302 --> 00:28:01.846 on the very lip of the drop-off. 00:28:20.323 --> 00:28:22.158 Where water doesn't drain away, 00:28:23.576 --> 00:28:25.912 the Heartland becomes wetland. 00:28:30.959 --> 00:28:32.919 The boggy forests of Ontario... 00:28:36.297 --> 00:28:38.341 ...just a little north of Niagara, 00:28:40.093 --> 00:28:43.596 and every bit as challenging for the local heroes. 00:28:50.687 --> 00:28:54.858 This spotted salamander was born in this pond just three months back. 00:28:57.527 --> 00:28:59.362 Now, she needs to leave 00:28:59.863 --> 00:29:04.200 and find a new home before this one dries out or freezes. 00:29:05.577 --> 00:29:08.204 But facing the unknown takes courage, 00:29:08.872 --> 00:29:11.166 especially when you're just two inches long. 00:29:16.546 --> 00:29:18.590 She waits till after sunset. 00:29:21.593 --> 00:29:22.719 By dark, 00:29:23.052 --> 00:29:26.681 this forest is a weird world of glowing mushrooms... 00:29:30.018 --> 00:29:33.146 and other more sinister surprises. 00:29:38.485 --> 00:29:42.071 It's a humid night, good conditions for her journey. 00:29:44.491 --> 00:29:46.576 She breathes partly through her skin, 00:29:47.911 --> 00:29:50.580 but that only works if the skin is wet. 00:30:02.425 --> 00:30:06.930 She needs to find a damp burrow to call home before she dries out. 00:30:08.473 --> 00:30:10.517 And hydration's not her only problem. 00:30:12.852 --> 00:30:14.395 There are night hunters about. 00:30:22.403 --> 00:30:24.280 She finds a promising spot. 00:30:25.990 --> 00:30:29.452 But this hole's already taken by an adult spotted salamander. 00:30:35.208 --> 00:30:37.168 Best to keep on moving. 00:30:40.338 --> 00:30:41.506 The clock is ticking. 00:30:46.886 --> 00:30:49.347 Her quest is becoming desperate. 00:30:53.726 --> 00:30:56.020 Could this be the home that she's been looking for? 00:31:02.068 --> 00:31:04.153 Nope, it's a trap. 00:31:05.780 --> 00:31:06.865 A pitcher plant. 00:31:08.533 --> 00:31:12.537 It will consume any prey trapped in its cup-shaped leaves. 00:31:17.041 --> 00:31:18.543 Usually, they take insects. 00:31:20.712 --> 00:31:21.963 But in this forest, 00:31:22.964 --> 00:31:24.340 they take prey... 00:31:25.842 --> 00:31:26.968 with bones. 00:31:36.394 --> 00:31:39.314 The plant's leaves have backward-facing hairs 00:31:39.772 --> 00:31:42.150 to stop the salamander from getting a grip. 00:31:48.239 --> 00:31:51.534 Soon, the plant's digestive juices will start to dissolve her, 00:31:52.327 --> 00:31:54.704 as they have many others before. 00:32:03.796 --> 00:32:05.256 All appears lost, 00:32:06.507 --> 00:32:07.675 but in the Heartland... 00:32:09.719 --> 00:32:12.722 a change in fortunes is never far away. 00:32:17.560 --> 00:32:19.646 The storm finally breaks. 00:32:23.775 --> 00:32:27.487 Every drop of rain raises the water levels in the pitcher... 00:32:29.322 --> 00:32:31.074 just a tiny bit. 00:32:38.706 --> 00:32:40.166 As the pitcher fills... 00:32:43.002 --> 00:32:45.046 she's lifted toward the exit. 00:32:56.224 --> 00:32:58.059 Saved by a storm. 00:33:04.107 --> 00:33:06.359 And soon, our brave salamander 00:33:06.859 --> 00:33:09.237 finds the dream burrow she's been searching for 00:33:09.862 --> 00:33:10.863 all along. 00:33:26.504 --> 00:33:27.755 In the Heartland, 00:33:27.964 --> 00:33:31.050 you've got to be prepared for unexpected dangers. 00:33:35.805 --> 00:33:37.473 Out on the South Dakota prairie, 00:33:39.392 --> 00:33:41.144 the bison are on the move. 00:33:46.524 --> 00:33:48.276 And the burrowing owls... 00:33:50.028 --> 00:33:51.738 have some new arrivals. 00:34:01.581 --> 00:34:02.749 Six owlets... 00:34:04.667 --> 00:34:07.920 getting their first look at the outside world. 00:34:10.882 --> 00:34:13.926 Feeding this crew is gonna be a full-time job. 00:34:20.391 --> 00:34:22.810 Mom's brought a juicy grasshopper. 00:34:29.567 --> 00:34:31.277 Now, over to Dad. 00:34:33.571 --> 00:34:36.365 He's brought... bison dung. 00:34:37.575 --> 00:34:39.035 Not what she was hoping for. 00:34:41.871 --> 00:34:43.873 Maybe some food next time. 00:34:44.957 --> 00:34:47.335 Nope, more dung. 00:34:49.128 --> 00:34:52.799 Again and again, dung. 00:34:54.092 --> 00:34:56.886 Mom looks... unimpressed. 00:35:01.474 --> 00:35:04.727 He's making a real smelly mess on the doorstep. 00:35:11.400 --> 00:35:14.570 But maybe Dad's got a plan. 00:35:21.077 --> 00:35:23.121 A prairie dog calls out an alarm... 00:35:25.081 --> 00:35:27.166 ...signaling danger in the town. 00:35:31.462 --> 00:35:32.505 A badger, 00:35:33.047 --> 00:35:36.467 an expert digger who's real hungry after the cold snap. 00:35:39.011 --> 00:35:43.182 The bite-sized owls must hunker down and keep quiet. 00:35:57.780 --> 00:36:00.867 The badger's relying on his nose to sniff out prey. 00:36:11.961 --> 00:36:13.880 And it looks like the smell of the dung 00:36:15.381 --> 00:36:17.508 has masked the smell of the owls. 00:36:26.267 --> 00:36:27.643 The badger moves on. 00:36:30.813 --> 00:36:31.856 A close call. 00:36:34.775 --> 00:36:35.943 Nice work, Dad! 00:36:44.285 --> 00:36:46.495 The drama isn't over for the day, though. 00:36:58.883 --> 00:37:00.176 With the heat rising, 00:37:01.719 --> 00:37:06.182 the bison bulls are preparing to fight for the chance to mate with the females. 00:37:10.436 --> 00:37:12.146 There's a battle brewing... 00:37:16.067 --> 00:37:17.276 ...on land... 00:37:19.987 --> 00:37:21.155 and in the sky. 00:37:43.761 --> 00:37:44.971 As the bulls collide, 00:37:46.347 --> 00:37:50.142 there's an even greater collision happening above their heads. 00:37:54.105 --> 00:37:59.527 Warm, humid air direct from the tropics is slamming into the cold Arctic air. 00:38:03.614 --> 00:38:06.075 Perfect conditions for a megastorm. 00:38:11.289 --> 00:38:15.334 The Heartland sees the most powerful thunderstorms on Earth. 00:38:18.254 --> 00:38:21.966 A single cloud can carry a billion volts of electricity. 00:38:28.097 --> 00:38:30.558 Two-hundred-mile-per-hour tornadoes... 00:38:35.187 --> 00:38:36.522 ...and torrential rain 00:38:37.481 --> 00:38:39.275 sweep across the prairie. 00:38:42.528 --> 00:38:44.989 It's a passion killer for the bison bulls. 00:38:49.160 --> 00:38:52.413 But ultimately, these storms are life-givers. 00:38:58.002 --> 00:39:00.087 They water the great grasslands... 00:39:02.256 --> 00:39:06.135 and help turn this region into the breadbasket of America. 00:39:09.430 --> 00:39:13.142 Nearly half of the US prairie is now farmland. 00:39:17.605 --> 00:39:22.985 In a land of extreme changes, this is the biggest change of all. 00:39:29.367 --> 00:39:33.287 But some Heartland heroes adapt to the modern world. 00:39:36.165 --> 00:39:38.167 Under this deserted ranch house... 00:39:40.628 --> 00:39:42.463 is a very rare sight. 00:39:50.304 --> 00:39:52.264 A family of bobcats. 00:40:00.147 --> 00:40:02.858 The four kittens are just six weeks old... 00:40:06.487 --> 00:40:09.156 and still completely reliant on Mom. 00:40:12.618 --> 00:40:17.790 She's chosen a great den site, out of the sun and hidden from predators. 00:40:19.375 --> 00:40:22.545 Though it can't shelter her from her playful kittens. 00:40:42.690 --> 00:40:44.024 Time to head out. 00:40:47.361 --> 00:40:51.490 Besides a break from the kids, she's gotta put dinner on the table. 00:41:00.291 --> 00:41:03.252 The world beyond the fence is dangerous. 00:41:07.715 --> 00:41:10.468 Bobcats are often hunted by humans. 00:41:13.554 --> 00:41:15.806 The kittens will be safe while she's gone, 00:41:16.348 --> 00:41:18.225 so long as they stay under the house. 00:41:26.233 --> 00:41:27.318 Uh-oh! 00:41:32.114 --> 00:41:35.367 This is the perfect playground for wannabe hunters. 00:41:48.631 --> 00:41:51.509 One day, with a little more practice, 00:41:52.134 --> 00:41:56.931 these little guys will be one of the most adaptable predators in America. 00:42:03.521 --> 00:42:09.235 They'll hunt everything. From rats, to insects, to birds in flight. 00:42:14.823 --> 00:42:16.116 Right now, though... 00:42:18.285 --> 00:42:20.704 ...the birds still have the upper hand. 00:42:31.298 --> 00:42:32.466 A Harris hawk. 00:42:52.820 --> 00:42:54.697 Not feeling so brave now. 00:42:59.410 --> 00:43:01.745 Thank goodness Mom chose a good shelter. 00:43:14.466 --> 00:43:15.634 In no time at all, 00:43:16.051 --> 00:43:18.596 the kittens will be out hunting on their own. 00:43:24.143 --> 00:43:25.227 As adults, 00:43:25.352 --> 00:43:28.355 each will hunt hundreds of rodents every year. 00:43:32.943 --> 00:43:34.862 A free pest control service 00:43:35.946 --> 00:43:38.991 for farmers who let the bobcats be. 00:43:49.168 --> 00:43:52.588 The Heartland rewards those who can adapt to change. 00:43:54.965 --> 00:43:57.259 Whether that's in the new world of farmland... 00:43:59.928 --> 00:44:04.141 ...or in the vast wild places of rolling hills and prairie. 00:44:09.355 --> 00:44:12.066 Youngsters here have to grow up fast. 00:44:20.157 --> 00:44:24.411 At just a month old, our owl chicks are learning to fly. 00:44:31.585 --> 00:44:35.255 Our bobcats are braving the world beyond the fence. 00:44:42.012 --> 00:44:46.642 And our wolf cubs are almost ready to run with the pack. 00:44:49.436 --> 00:44:52.523 As they grow, every one of these youngsters 00:44:52.731 --> 00:44:55.359 is destined to become a hero 00:44:56.151 --> 00:44:58.779 of the great American Heartland.