WEBVTT

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Welcome to North America.

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The most diverse continent on Earth.

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The only place where you can find
every landscape, from polar ice cap...

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to baking desert,
and everything in between.

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Whatever the neighborhood,
there's a hero who can make it a home.

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Smart, tough, brave, you name it.

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They all have what it takes to thrive...

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in the wildest, most beautiful
continent on Earth.

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The American Southwest,
from Texas to California,

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is a spectacular world of desert and rock.

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An arid wonderland
where water, when it comes,

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shapes the land and the lives
of all that live here.

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The Grand Canyon.

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Three hundred miles long
and 6,000 feet deep.

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An inaccessible place
that's pretty good at keeping secrets.

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That's why the
animal that rules this

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world has been
shrouded in mystery...

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until now.

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A mountain lion.

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Filmed in the Grand Canyon
for the very first time.

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Two hundred pounds of muscle.

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He's on a quest to keep out rivals...

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and father the next generation of big cats
in his kingdom.

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But his success,
and that of all life here,

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will ultimately depend on events
500 miles away,

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where the Southwest desert
meets the Pacific Ocean.

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It's springtime,
and off the coast of Baja California,

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a new life is just beginning.

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A baby gray whale.

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Birthweight, a healthy 2000 pounds.

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This proud mom travelled
for months without food

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to give birth in this sheltered lagoon...

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a safe haven from predators.

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Now, she's building a bond with her son
and feeding him 50-percent-fat milk.

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One problem, though.
There's no food here for Mom.

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So she's about to lead her calf,
just eight weeks old,

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on the longest mammal migration on Earth.

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But they're not alone.

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Ninety-nine percent
of the world gray whale population

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sets off from here each year,

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to swim 6,000 miles back
to their Arctic feeding grounds.

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The calf has been putting on
200 pounds a day.

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He's raring to go.

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Only Mom knows
the challenges that lie ahead

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as they journey the length
of our continent's West Coast.

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This is truly America's whale.

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All along this coastline,
the Pacific is a life-giver.

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Off California, the sun's heat
draws water from the cold ocean...

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creating a fog bank, which blows inland
on the sea breeze.

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This coastline is bathed in fog
for 60 days a year,

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providing much of the water
for the world's tallest trees.

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Three-hundred-foot coastal redwoods

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drink the droplets through their leaves.

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The fog also supports
less-celebrated trees.

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This oak is the storehouse
for a family of acorn woodpeckers.

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They live to stash acorns.

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All day, every day.

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Almost to the point of... obsession?

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But 50,000 acorns stored in the bark
of one oak?

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That's bound to attract thieves.

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One woodpecker is always on lookout.

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Looks like a win for the squirrels.

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But the lookout's called in backup.

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By working together,
they keep their stash safe.

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But not for long.

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This thief has his own power tools

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to break into the family vault.

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Even the most committed teamwork
is no defense

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against a raider
a thousand times your size.

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All that hard work, undone in minutes.

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These hoarding heroes don't let
a little setback get them down.

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The new collection begins straightaway.

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The woodpeckers' oak
is watered by Pacific fog.

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Travel away from the coast,
and that water supply evaporates.

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A hundred and fifty miles inland,

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the Sierra Nevada Mountains capture
the Pacific clouds.

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These mountains are a wall,
up to 14,000 feet high,

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blocking water from blowing
further inland.

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Beyond is the ultimate desert world.

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The hottest place on Earth.

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Death Valley.

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Here, the summer temperature
can reach 130 degrees.

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Even in spring, it can top a hundred.

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So, how do you survive in this land
hardly ever reached by rain?

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One tiny desert dweller has a solution
straight out of a science fiction movie.

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Ten feet underground,

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where it's an ideal temperature
year-round.

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A bizarre insect society.

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These are honeypot ants.

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Some members of
the species only exist

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to store food for others.

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The worker ants gather flower nectar
in times of plenty

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and feed it to others,

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who never leave the colony.

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Their abdomens swell to the size of
a cherry with sweet nectar.

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It's the colony's insurance policy
against hard times.

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Now, the precious honeypots are full

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and kept clean by their comrades

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to keep 'em healthy.

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But in this corner of Death Valley,
the driest place in North America,

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it hasn't rained all winter.

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If this drought goes on much longer,

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these desert survivalists
will need a plan B.

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Two hundred and fifty miles
further inland,

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the Colorado River carves through
the high desert of Arizona

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to form the Grand Canyon.

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This spring morning brings
a first-ever glimpse

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into the private life
of the Canyon's most elusive resident.

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Our mountain lion
is on a mission to breed.

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Like all male mountain lions,
he's a loner.

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His scarred face shows he'll fight
to keep rival males out of his kingdom.

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But his biggest battle
is finding a female.

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There's only a handful
in a hundred square miles of this canyon,

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so he can't rely on a chance encounter.

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He needs to advertise.

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His scent mark will last for weeks...

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a message to any passing females

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that this eligible bachelor
is looking for love.

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For others in the West, finding a mate
is the least of their worries.

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Over 20 million free-tailed bats,

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one of the largest gatherings of mammals
on Earth,

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flock to this sheltered Texas cave
each spring to mate and have pups.

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These baby bats have to grow up fast.

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Tonight, at just a month old,

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this little guy will fly up to
a hundred miles in search of food...

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on his very first flight.

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As evening falls, the bats start to leave.

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They'll get more time to feed
by heading out early...

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but leaving their sanctuary in daylight
is a gamble.

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There's danger from above.

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A Swainson's hawk.

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And even greater danger from below.

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Cactus spines snag
the inexperienced pups...

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making them an easy target.

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Coachwhip snakes.

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Their large eyes mark them out
as visual hunters.

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Non-venomous, they rely
on dagger-sharp teeth to catch their prey.

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And if a bat makes a run for it,

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it stands no chance against
the fastest snake in North America.

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Despite the danger,
every bat has to head out sometime...

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or starve.

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What a time to take
your first-ever flight.

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His only chance is to climb quickly

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to somewhere he can re-launch.

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Sometimes, you just need a bit of luck.

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This young bat's cleared
the most dangerous hurdle

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on his path to adulthood.

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Tonight, he and the rest of his colony
will devour 250 tons of insects

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in the Southwest skies.

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Back in the Pacific, the clock is ticking
for the gray whale mom and calf.

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They're averaging three miles an hour
on their journey up the West Coast

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to the summer feeding grounds.

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If he can memorize landmarks like this,

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it will help him navigate

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when he's old enough
to make this migration on his own.

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No time to hang out, though.

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Mom knows it's still a long way,

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4,000 miles to
the Alaskan Arctic.

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Next stop, a wonder of the American West.

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A forest of giant kelp,
growing up to 18 inches a day,

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fueled by the California sun.

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This is the ocean equivalent
of a tropical rainforest...

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full of life at every level.

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Sea otters take it easy in the kelp beds.

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Moms can even get daycare here,
from the kelp.

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Wrapped up in weed,
this youngster won't drift away.

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And Mom can go free diving.

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She can hold her breath
for up to eight minutes

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while she hunts on the seabed.

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Her favorite spot is the surf zone,
near the shore,

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where the waves churn up nutrients,
feeding beds of shellfish.

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The otters thrive
on this protein-rich superfood.

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There's plenty for everyone,

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if you can hold
on to your catch.

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The ocean supplies
all the otters' needs...

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even rocks from the seafloor
to smash open mussels.

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Many sea otters spend
their entire lives at sea,

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where the year-round riches
are in stark contrast to the land.

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In the desert,
the scorching summer is just weeks away.

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And somebody's in a hurry
to raise a family.

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A Costa's hummingbird,

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the hardest-working
mom in America.

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She's on a mission,
at 2,000 wingbeats a minute,

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collecting dried grass and spiderwebs
to build a nest.

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She has just five
weeks to raise a brood,

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and she needs just
one more ingredient...

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that only a male can provide.

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The mom's short on time,
but she's still really picky.

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He sticks out his throat feathers.

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He's throwing some great shapes.

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But she's still not sure
this thumb-sized heartthrob is the one.

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He'll have to pull out his very best move.

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He climbs to a hundred feet...

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then dives at 60 miles per hour.

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Whistling tail feathers
are the soundtrack to his show.

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That dive...

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That face...

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Now she's sure.

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After the briefest of encounters,

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the mom soon has eggs to lay.

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And now, the real hard work begins.

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In the sweltering heat,
she's soon visiting

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up to 2,000 flowers a day
to feed her brood.

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Twins. Twice the work.

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Each chick started out
just half the weight of a dollar bill.

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She feeds them up on a protein shake
of insects and nectar.

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In just 21 days, they're ten times heavier
than when they hatched...

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and ready to take their very first flight.

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Supermom has done it...

00:28:42.413 --> 00:28:44.582
and just before the summer heat hits.

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Soon, they'll have to leave
for the coast, where it's cooler.

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Our gray whales have traveled
another 300 miles since leaving L.A.

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The mom now hasn't eaten for six months.

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She's lost a fourth of her body weight

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while feeding her calf
six gallons of milk a day.

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She needs to reach the feeding grounds
ASAP.

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And now, she faces a choice.

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Does she save energy and take a shortcut
across Monterey Bay,

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a dangerous 25-mile stretch
of open water,

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or keep on hugging the shoreline?

00:29:56.278 --> 00:29:59.073
She puts the safety of her calf
above her hunger

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and stays inshore,
hidden in the kelp forest.

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Another less experienced mom

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chooses to take her calf
straight across the bay.

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The wrong call. Orcas.

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This pod comes here
at this time every year

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to hunt gray whale calves.

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The older orcas teach the young ones
how to hunt.

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First, they ram the calf
at 30 miles per hour.

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When the gray whale mom tries to
lead her wounded youngster to safety

00:31:13.981 --> 00:31:15.065
in the kelp forest,

00:31:15.274 --> 00:31:17.401
other orcas block their path.

00:31:21.322 --> 00:31:25.409
Working together, they drive their prey
back to deep water,

00:31:26.660 --> 00:31:29.497
and separate the calf from its mother.

00:31:49.266 --> 00:31:54.605
Their plan has worked.
Now they drown the calf.

00:32:13.415 --> 00:32:14.917
It's a cruel lesson,

00:32:16.418 --> 00:32:20.297
but this young mother will have
other calves in years to come.

00:32:26.428 --> 00:32:30.474
For our more experienced mom,
sticking to the American coast

00:32:30.599 --> 00:32:32.393
has saved her calf's life.

00:32:35.020 --> 00:32:36.939
They've passed
the most dangerous test

00:32:37.022 --> 00:32:38.566
on their journey to Alaska...

00:32:43.487 --> 00:32:48.242
and they're getting out of the West
just as the toughest time of year begins.

00:32:55.249 --> 00:32:56.375
Summer.

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Sun beating on the bare rock
turns the Grand Canyon into an oven.

00:33:20.649 --> 00:33:22.943
Our mountain lion seeks out the shade.

00:33:30.242 --> 00:33:32.536
Still no sign of a female...

00:33:35.998 --> 00:33:39.168
so he posts a new message
on the big cat dating site.

00:33:45.007 --> 00:33:46.634
Then he waits for evening...

00:33:51.722 --> 00:33:53.891
when the Canyon animals get active.

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Deer are his favorite food...

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...though he's not fussy.

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He knows every inch
of his 150-square-mile kingdom.

00:34:26.340 --> 00:34:28.801
The Canyon rim is
a favorite hunting ground

00:34:28.884 --> 00:34:30.511
for this stealth hunter.

00:34:35.224 --> 00:34:38.644
With night vision
nearly ten times better than a human's.

00:34:44.149 --> 00:34:47.069
He's returning to a kill he's made
a few nights back.

00:34:52.533 --> 00:34:55.202
He can eat 40 pounds of meat in a day,

00:34:55.744 --> 00:34:59.081
but it could still take him a week
to chow down a whole elk.

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His belly's full.
He goes to sleep off his meal.

00:35:18.851 --> 00:35:24.732
And while the cat's away...
thieves move in.

00:35:29.737 --> 00:35:33.031
Most mountain lion kills
get raided by black bears,

00:35:35.784 --> 00:35:38.912
just one of many that benefit
from the lion's leftovers.

00:35:48.130 --> 00:35:51.759
The King of the Canyon
is both predator and provider.

00:36:06.940 --> 00:36:09.818
July in Death Valley.

00:36:12.613 --> 00:36:14.990
There's been no rain now for six months.

00:36:16.074 --> 00:36:19.453
Through the drought,
the honeypot ants have gradually drained

00:36:19.536 --> 00:36:22.164
all the nectar they'd stored
in their nestmates.

00:36:33.634 --> 00:36:35.302
So with nothing left to eat,

00:36:35.886 --> 00:36:38.472
the workers are setting out
on a raiding party.

00:36:41.266 --> 00:36:44.144
They must be quick.
By the middle of the day,

00:36:44.311 --> 00:36:46.939
the surface can hit 200 degrees.

00:36:49.691 --> 00:36:51.944
That's hot enough to cook an ant
in seconds.

00:36:59.159 --> 00:37:01.286
They find a rival
from another colony.

00:37:04.373 --> 00:37:09.753
They size her up and follow her scent
back to her nest.

00:37:21.014 --> 00:37:24.226
Here, they find ants
still full of nectar,

00:37:25.018 --> 00:37:28.939
black from food found on tree roots
deep underground.

00:37:38.323 --> 00:37:40.450
Buried treasure
worth fighting over.

00:37:57.593 --> 00:38:01.179
The starving invaders eat some honeypots
on the spot.

00:38:02.764 --> 00:38:06.852
Others, they capture
and drag back to their home colony.

00:38:24.161 --> 00:38:26.413
The raiders will have to
get home fast,

00:38:27.873 --> 00:38:31.168
because a force of nature
is building nearby.

00:38:39.176 --> 00:38:40.969
The thundercloud collapses

00:38:41.345 --> 00:38:45.557
into a monster dust storm
known as a haboob.

00:38:54.483 --> 00:38:59.321
Most ants make it back just before
the 60-mile-an-hour wall of sand

00:39:00.030 --> 00:39:02.157
takes out any stragglers in its path.

00:39:20.092 --> 00:39:22.135
The entrance
to the nest is buried,

00:39:22.511 --> 00:39:27.724
but the stolen honeypots will ensure
the colony's survival... for now.

00:39:34.398 --> 00:39:37.074
By late summer,
the heat and drought

00:39:37.098 --> 00:39:40.195
across the West are
almost unbearable.

00:39:44.408 --> 00:39:46.827
Even clouds don't signify rain.

00:39:53.375 --> 00:39:57.713
These are pyrocumulus, fire clouds,

00:39:58.714 --> 00:40:03.510
formed by soot particles
rising high into the sky above wildfires.

00:40:06.221 --> 00:40:09.171
They can climb up
to seven miles high,

00:40:09.195 --> 00:40:12.144
the edge of the stratosphere.

00:40:26.033 --> 00:40:29.202
Hotter summer temperatures,
caused by climate change,

00:40:29.870 --> 00:40:33.874
are making wildfire season
increasingly extreme across the West.

00:40:40.047 --> 00:40:44.551
The residents of Los Angeles
are all too familiar with these infernos.

00:40:53.852 --> 00:41:00.400
Homes and wildlife habitat are regularly
destroyed, right up to the city limits.

00:41:09.785 --> 00:41:12.370
But there's an oasis
in Tinseltown.

00:41:16.833 --> 00:41:20.128
Griffith Park,
right in the heart of Hollywood.

00:41:22.089 --> 00:41:24.314
Protected from fires,
these well-watered

00:41:24.338 --> 00:41:26.843
lawns are a haven for wildlife.

00:41:36.770 --> 00:41:40.232
And after dark,
this park really comes alive.

00:41:47.239 --> 00:41:51.326
There's prey... and predators.

00:41:54.162 --> 00:41:57.833
Bobcat... coyote...

00:42:00.293 --> 00:42:04.548
and one A-list star
with an amazing backstory.

00:42:09.594 --> 00:42:11.346
When he found himself homeless,

00:42:12.514 --> 00:42:17.102
this intrepid hero made a 50-mile trek
along the Santa Monica Mountains.

00:42:19.354 --> 00:42:22.440
He crossed the busiest freeway
in the U.S...

00:42:30.532 --> 00:42:32.909
right into the heart of the city.

00:42:41.877 --> 00:42:47.215
Meet P-22,
the world's most famous mountain lion.

00:42:49.217 --> 00:42:52.721
As there's so much prey in this park,
he thrives in a territory

00:42:52.888 --> 00:42:56.391
just five percent the size
of his Grand Canyon cousins'.

00:42:58.727 --> 00:43:01.605
His radio collar sends scientists
his location.

00:43:13.491 --> 00:43:17.704
In the small hours, he leaves
the park and prowls the city streets.

00:43:22.834 --> 00:43:25.670
If it's a mate he's after,
he's out of luck.

00:43:27.714 --> 00:43:30.508
There's next to no chance
another mountain lion

00:43:30.592 --> 00:43:33.178
will ever emulate his amazing journey.

00:43:37.849 --> 00:43:42.354
But he can find something in the city
that's in very short supply.

00:43:46.441 --> 00:43:47.442
Water.

00:43:52.239 --> 00:43:55.742
In the heat of the summer,
a broken water pipe can be a lifeline.

00:44:09.172 --> 00:44:13.551
But for those across
the parched West without a water supply,

00:44:14.302 --> 00:44:16.805
hope is finally on the horizon.

00:44:21.476 --> 00:44:25.397
In late summer, the winds shift
over the Pacific Ocean,

00:44:28.358 --> 00:44:30.986
blowing rain clouds
hundreds of miles inland.

00:44:39.244 --> 00:44:44.082
This is the beginnings of one of the most
powerful weather systems in America.

00:44:46.084 --> 00:44:47.961
The American monsoon.

00:44:56.344 --> 00:45:00.390
For three months,
torrential downpours drench the Southwest.

00:45:08.815 --> 00:45:12.277
These storms can drop
two inches of rain in an hour,

00:45:15.071 --> 00:45:17.324
rejuvenating the barren deserts.

00:45:25.081 --> 00:45:28.126
This region can get
up to half its annual rainfall

00:45:28.209 --> 00:45:29.794
in this late-summer monsoon.

00:45:42.682 --> 00:45:44.392
The rain from the distant ocean

00:45:44.851 --> 00:45:48.146
is the secret to life
in America's deserts.

00:45:50.565 --> 00:45:52.650
All the way to the top
of the food chain.

00:45:55.111 --> 00:45:58.031
A new mountain lion
in the Grand Canyon.

00:45:59.783 --> 00:46:01.451
Not the scarred-face male...

00:46:04.329 --> 00:46:05.580
...but a female.

00:46:07.165 --> 00:46:11.169
After the recent rain, she can travel
outside of her usual range,

00:46:13.380 --> 00:46:16.800
safe in the knowledge that
there'll be drinking water to be found.

00:46:35.652 --> 00:46:37.070
This first-ever look

00:46:37.153 --> 00:46:39.739
into the lives of
the Grand Canyon's mountain lions

00:46:40.615 --> 00:46:43.127
shows that big
cats are still thriving

00:46:43.151 --> 00:46:45.662
in this iconic
American wilderness.

00:46:49.290 --> 00:46:51.000
A source of hope for the future.

00:47:00.969 --> 00:47:05.056
This female is on her own, no cubs.

00:47:08.810 --> 00:47:12.230
So, quite likely, she's in season,
looking for a mate.

00:47:14.482 --> 00:47:17.569
She's found the scent marks
of the scarred-faced male...

00:47:23.616 --> 00:47:25.910
her first introduction
to a potential partner.

00:47:35.628 --> 00:47:39.591
And following on,
just an hour later, is the male.

00:47:44.888 --> 00:47:46.473
He'll soon achieve his goal,

00:47:47.098 --> 00:47:50.310
another generation of big cats
in his kingdom...

00:47:54.355 --> 00:47:58.276
true heroes of the great American West.