Original subtitles

ANNOUCNER: WHEN YOU SEE THIS SYMBOL YOU KNOW YOU'RE

WATCHING TELEVISION THAT'S EDUCATIONAL AND INFORMATIONAL

THE MORE YOU KNOW ON NBC.

DYLAN: I'M DYLAN DREYER, JOIN ME FOR A FRONT ROW

SEAT TO THE MOST SPECTACULAR ANIMAL

MIGRATIONS ON EARTH.

WE'LL WITNESS THE EPIC FLIGHT OF THE MONARCH

BUTTERFLY.

SOAR HIGH WITH GEESE HEADING SOUTH FOR WINTER.

RIDE WITH GRAY WHALES ALONG THE NORTH AMERICAN

COASTLINE.

AND FIND OUT WHAT LIFE IS LIKE FOR VILLAGERS WHO

LIVE ALONGSIDE ONE MILLION RED CRABS.

♪ MUSIC ♪

DYLAN: EVERY SUMMER MILLIONS OF TINY EATING

MACHINES ARE HATCHED ACROSS NORTH AMERICA.

THEY EAT VORACIOUSLY UNTIL THEY GROW LARGE ENOUGH TO

BEGIN THE MOST AMAZING TRANSFORMATION IN THE

ANIMAL KINGDOM.

OUR JOURNEY BEGINS IN THE REMOTE FORESTS OF CENTRAL

MEXICO.

DYLAN: LARVA IS THE NAME GIVEN TO ANIMALS THAT

WILL UNDERGO A MAJOR METAMORPHOSIS BEFORE

BECOMING AN ADULT.

DYLAN: THIS LITTLE LARVA IS A CATERPILLAR.

WHEN IT'S BIG AND FAT ENOUGH THIS CREATURE WILL

SPIN A SILK COCOON AND TRANSFORM INTO ONE OF

NATURE'S MOST SUBLIME CREATIONS.

IT HAS BECOME A MONARCH BUTTERFLY.

GENERATION BY GENERATION WAVES OF MONARCH

BUTTERFLIES WILL MIGRATE NORTH THROUGH MEXICO

ACROSS THE UNITED STATES, AS FAR AS SOUTHERN CANADA.

DYLAN: IT TAKES AS MANY AS FOUR GENERATIONS

OF BUTTERFLY TO COMPLETE THE TRIP

ACROSS NORTH AMERICA.

THE FINAL FOURTH GENERATION MAY NOT LOOK

ANY DIFFERENT FROM THE ONES THAT CAME BEFORE, BUT

IT IS.

DYLAN: INSTINCT TELLS THIS FOURTH GENERATION NOT

TO MATE, BUT INSTEAD TO PREPARE FOR THE IMPOSSIBLE

JOURNEY BACK HOME TO MEXICO.

THEY URGENTLY GATHER FOOD, LOADING NECTAR THROUGH A

STRAW-LIKE PROBOSCIS.

MEMBERS OF THIS LAST GENERATION WILL LIVE AT

LEAST EIGHT TIMES LONGER THAN THEIR PREDECESSORS,

ENABLING THEM TO COMPLETE THE LONGEST INSECT

MIGRATION ON EARTH.

USING PREVALING WINDS WHEN POSSIBLE, THEY COVER 100

MILES A DAY.

ESCAPING THE NORTHERN WINTER, THEY NAVIGATE

SOUTH TOWARDS THE BIRTHPLACE OF THEIR

GREAT-GREAT-GRANDPARENTS.

CONVERGING FROM ACROSS THE CONTINENT, AS MANY AS HALF

A BILLION SWEEP SOUTH TOWARDS CENTRAL MEXICO ON

A JOURNEY OF 2,500 MILES.

ONLY 1 IN 5 WILL SURVIVE, BUT THEIR NUMBERS ARE SO

VAST 100 MILLION OF THEM WILL COMPLETE THE JOURNEY,

FINALLY ARRIVING BACK TO THE SMALL PATCHES OF

MOUNTAIN FORESTS FROM WHERE THEY CAME.

HOW SOMETHING THE SIZE OF A LEAF CAN NAVIGATE ACROSS

AN ENTIRE CONTINENT TO A PLACE IT HAS NEVER BEEN

REMAINS ONE OF THE GREATEST MYSTERIES OF

NATURE.

[CHURCH BELLS]

DYLAN: THE RETURN OF THE MONARCHS HOLD MYSTICAL

SIGNIFICANCE FOR THE PEOPLE OF MEXICO.

THE MONARCHS' RETURN COINCIDES WITH AN ANCIENT

CELEBRATION CALLED THE DAY OF THE DEAD.

VILLAGERS GATHER IN CEMETERIES WITH INCENSE

AND CANDLES TO WELCOME BACK THE SOULS OF DEPARTED

LOVED ONES.

MANY OF THESE VILLAGERS BELIEVE THEIR LOVED ONES

RETURN ON THE WINGS OF BUTTERFLIES.

DYLAN: IN THE FORESTS ABOVE THE VILLAGE THE LAST OF

THE MONARCHS HAVE ARRIVED FROM THEIR EPIC MIGRATION.

THROUGH THE WINTER THEY HANG TOGETHER ALMOST

MOTIONLESS IN A KIND OF DORMANT-LIKE STATE.

A SINGLE TREE COULD HOLD TENS OF THOUSANDS, SO MANY

FEATHER-WEIGHT CREATURES THEIR COMBINED MASS CAN

BREAK BRANCHES.

THE MONARCHS' WINTER HOMES ARE PROTECTED RESERVES.

BUT TO THE SCHOOL CHILDREN THAT VISIT THEY ARE MAGIC

FORESTS.

♪ MUSIC ♪

DYLAN: THE BUTTERFLIES WILL ONLY MOVE WHEN WARM

ENOUGH.

AND A GENTLE BREATH IS ALL IT TAKES TO TRIGGER A

CASCADE.

[SOUND OF BUTTERFLY WINGS]

DYLAN: AS SPRING APPROACHES ANOTHER GREAT

NORTHERN MIGRATION CAN BEGIN AND IT'S FINALLY

TIME FOR THIS GENERATION TO MATE.

THE FEMALES BEGIN THE NEXT GREAT EXODUS BACK TO

SOUTHERN CANADA, CARRYING THEIR FERTILIZED EGGS

TOWARD THE AMERICAN HEARTLAND.

♪ MUSIC ♪

DYLAN: ALONG WITH THOSE EGGS THEY ALSO CARRY THE

INCREDIBLE SECRETS OF HOW THEIR

GREAT-GREAT-GRANDCHILDREN WILL ONE DAY FIND THEIR

WAY BACK HOME.

A LITTLE 2-INCH LONG INSECT COMPLETING A

MIGRATION AS MYSTERIOUS AND WONDROUS AS ANY ON

EARTH, NOW THAT'S WHAT I CALL AN EPIC JOURNEY.

COMING UP NEXT, AUTUMN HAS ARRIVED IN CANADA AND

THESE MAGNIFICENT FEATHERED FLIERS ARE

GETTING READY TO TAKE TO THE SKY.

AND LATER, SOME OF THE LARGEST MAMMALS ON EARTH

COMPLETE ONE OF THE LONGEST MIGRATIONS ON THE

PLANET.

THE JOURNEY CONTINUES AFTER THIS.

ANNOUNCER: WE'LL BE RIGHT BACK TO THE MORE YOU KNOW ON NBC.

ANNOUNCER: WE NOW RETURN TO THE MORE YOU KNOW ON NBC.

DYLAN: ALL OF US HAVE DREAMED OF SPREADING OUR

WINGS AND FLYING THROUGH THE CLOUDS JUST LIKE A

BIRD.

FOR MOST OF OUR FEATHERED FRIENDS THE GIFT OF FLIGHT

ALSO COMES WITH A POWERFUL GIFT OF NAVIGATION, THE

ABILITY TO READ THE INVISIBLE FORCES OF OUR

PLANET LIKE A MAP THROUGH THE SKY.

[SOUNDS OF GEESE]

DYLAN: OF ALL NATURE'S MIGRATORS NONE TRAVEL

FARTHER OR IN GREATER NUMBERS THAN BIRDS.

THEIR PREPARATION FOR TRAVEL IS INTENSE.

CHICKS BORN IN SPRING MUST GROW LARGE ENOUGH TO

MIGRATE WITH THE ADULTS BY AUTUMN.

THEIR AVIATION FUEL COMES IN THE FORM OF FAT THAT

THEY PACK ON THEIR BODIES TO POWER THE LONG FLIGHT

SOUTH FOR THE WINTER.

SOME GROW SO HEAVY THEY CAN BARELY TAKE OFF.

BUT WHEN THE TIME IS RIGHT THEY GROW RESTLESS AND

EAGER.

THE COOL BREEZE OF AUTUMN WARNS THAT WINTER IS

COMING.

THEY CAN TELL WHEN THE WEATHER AND WINDS ARE MOST

FAVORABLE TO FLIGHT.

SIGNALS THAT ONLY THEY CAN PERCEIVE PULL THEM

FORWARD, SOUTH TOWARD WARMTH, UP OFF THE GROUND.

♪ MUSIC ♪

♪ MUSIC ♪

DYLAN: THE SECRETS OF MIGRATORY BIRDS HAVE

ELUDED OUR UNDERSTANDING SINCE EARLY HISTORY.

BUT TODAY MODERN RADAR THAT WAS ORIGINALLY

DESIGNED TO TRACK AIRCRAFT AND WEATHER PATTERNS HAS

BEGUN TO PEER INTO THE WORLD OF BIRDS.

RESEARCHERS HAVE CONFIRMED THAT MOST SMALL BIRDS

MIGRATE AT NIGHT AND CONSERVE ENERGY BY RIDING

STORM WINDS AND PREVAILING AIR CURRENTS.

RADAR STUDIES HAVE ALSO DISCLOSED FLIGHT SPEEDS,

TRAVEL ROUTES AND FLOCK SIZES, AND EVEN REVEAL

THAT BIRDS MIGRATE IN GREATER NUMBERS THAN

PREVIOUSLY THOUGHT, OVER DISTANCES ONCE UNIMAGINED.

SOME 5 BILLION BIRDS MIGRATE EACH YEAR FROM

EUROPE DEEP INTO AFRICA, AND SIMILAR NUMBERS ACROSS

ASIA AND THE AMERICAS.

TO FIND THEIR WAY AROUND THE GLOBE BIRDS EMPLOY A

REMARKABLE ARRAY OF TECHNIQUES.

INITIALLY BASIC INSTINCT POINTS THEM IN THE RIGHT

DIRECTION.

WHEN POSSIBLE THEY FOLLOW LANDMARKS.

AND WHERE NO LANDMARKS ARE FOUND THEY TURN TO

COMPASSES PROVIDED BY NATURE.

DAY FLIERS TAKE THEIR BEARINGS FROM THE SUN'S

POSITION WHILE BILLIONS OF NIGHT FLIERS SEEM TO

ORIENT THEMSELVES WITH THE SETTING SUN BEFORE THEY

SET OUT.

NIGHT FLYING OFFERS ADVANTAGES; PROTECTION

FROM PREDATORS AND SMOOTHER, COOLER AIR FOR

EASIER FLIGHT.

BUT NAVIGATION THROUGH THE DARK IS DIFFICULT.

LIKE EARLY SHIP CAPTAINS AND PILOTS, SOME BIRDS USE

THE STARS AS A COMPASS AND FLY TOWARD FAMILIAR

CONSTELLATIONS.

WHEN CLOUDS OBSCURE THE STARS AN INTERNAL MAGNETIC

COMPASS THAT CAN PERCEIVE THE EARTH'S MAGNETIC FIELD

MAY GUIDE THEM.

OCCASIONALLY THAT FIELD IS VISIBLE TO US HUMANS IN

THE FORM OF THE AURORAS.

DETECTING THE EARTH'S MAGNETIC FIELD IS A MARVEL

OF NATURE.

IT TOOK HUMANS THOUSANDS OF YEARS TO LEARN THIS

SKILL.

BUT SOME BIRDS ARE BORN TO READ THE PLANET LIKE A MAP

ETCHED INTO THEIR VERY DNA.

EQUIPPED BY NATURE WITH A REMARKABLE ARRAY OF

NAVIGATIONAL SKILLS, USING WHICHEVER GUIDE BEST SUITS

THEM FROM MOMENT TO MOMENT, BIRDS ARE THE

MASTER NAVIGATORS OF THE ANIMAL KINGDOM.

DYLAN: COMING UP NEXT, GRAY WHALES ARE HEADING SOUTH

TO WARMER WATERS TO GIVE BIRTH.

[WHALE CALL]

DYLAN: BUT ONE INFANT WAS BORN TOO SOON.

THE RACE IS ON TO SAVE AN ORPHANED WHALE WHEN OUR

JOURNEY CONTINUES.

ANNOUNCER: WE'LL BE RIGHT BACK TO THE MORE YOU KNOW ON NBC.

ANNOUCNER: WE NOW RETURN TO THE MORE YOU KNOW ON NBC.

DYLAN: THE ARCTIC OCEAN LOCATED AROUND THE NORTH

POLE IS ONE OF THE MOST EXTREME ENVIRONMENTS ON

THE PLANET.

IN ORDER TO SURVIVE THE ICY TEMPERATURES MANY

SPECIES MUST MIGRATE AWAY FROM THE ARCTIC OCEAN

DURING THE WINTER.

AND THE BIGGER THE ANIMAL THE FARTHER THEY TRAVEL.

DYLAN: THE COLD, NUTRIENT-RICH WATERS OF THE NORTHERN

PACIFIC PROVIDE AN ABUNDANCE OF FOOD FOR

MIGRATING SEA ANIMALS.

DYLAN: BUT WHEN WINTER ARRIVES MANY CREATURES BEGIN THEIR

YEARLY MIGRATION SOUTH TO MATE AND GIVE BIRTH IN

PLACES OF WARMTH AND SAFETY.

DYLAN: OF ALL THE EPIC ANIMAL MIGRATIONS ON EARTH, GRAY

WHALES MAKE THE LONGEST OF ANY WILD MAMMAL; SWIMMING

NONSTOP DAY AND NIGHT WITHOUT FEEDING FOR TWO

MONTHS, OVER A DISTANCE OF 5,000 MILES FROM THE

ARCTIC OCEAN TO THE SHORE OF MEXICO.

DYLAN: THEY OFTEN NAVIGATE THROUGH DARK AND MURKY

SEAWATER USING ECHOLOCATION.

[WHALE SOUNDS]

DYLAN: LIKE SUBMARINES, GRAY WHALES SEND OUT AND

RECEIVE SOUND WAVES THAT SKETCH ACOUSTIC IMAGES OF

THE UNDERSEA TERRAIN.

DYLAN: TRAVELING NEAR SHORE, GRAYS MAY ALSO RELY ON

FAMILIAR COASTAL LANDMARKS TO GUIDE THEM ON THEIR

JOURNEY.

AND THEY MAINTAIN THEIR BEARINGS BY SIMPLY KEEPING

THE SOUND OF THE ROLLING SURF TO THEIR LEFT WHEN

HEADING SOUTH AND TO THEIR RIGHT WHEN RETURNING

NORTH.

PREGNANT FEMALES LEAD THE MIGRATION SOUTH IN ORDER

TO REACH MEXICO BEFORE GIVING BIRTH.

UNFORTUNATELY THEIR TIMING IS NOT ALWAYS PERFECT.

NEWS ANCHOR: L.A.

COUNTY LIFEGUARDS WERE THE FIRST TO REACH THE 13-FOOT

LONG GRAY WHALE.

EXPERTS TELL US IT'S A FEMALE AND THEY THINK

SHE'S LESS THAN A WEEK OLD BECAUSE PART OF THE

UMBILICAL CORD IS STILL ATTACHED.

IT SAID THE MOTHER MAY HAVE STARTED SOUTH LATE,

GIVING BIRTH ALONG THE WAY TO AN ORPHAN NOW BADLY

DEHYDRATED AND MALNOURISHED.

RESCUE EFFORTS ARE UNDERWAY TO BRING THE BABY

WHALE OUT OF THE WATER AND TRANSPORT HER TO AN

EMERGENCY CARE CENTER AT SEAWORLD IN SAN DIEGO TWO

HOURS AWAY.

WOMAN: I NEEDED TO DRIVE THAT TRUCK AS FAST AS I

COULD, AS FAST AS THE TRUCK WOULD GO, AND I KNEW

TIME WAS OF THE ESSENCE.

AND THEN THE CHP WOULD JUST ZOOM RIGHT ON AHEAD,

CLOSE OFF TRAFFIC AND LET THIS WHALE GO ON BY.

MAN: WHEN I FIRST SAW THE WHALE I HONESTLY DIDN'T

THINK THAT SHE WAS ALIVE.

WE SEE ANIMALS LIKE THIS ALL THE TIME AND THE

MAJORITY OF THEM COME IN AND DIE VERY SOON AFTER OR

ARRIVE DEAD.

DYLAN: THEY NAME HER J.J.

AND BEGIN ROUND-THE-CLOCK CARE.

THEY MUST QUICKLY LEARN HOW TO TAKE THE PLACE OF A

MOTHER WHALE.

MAN: IT WAS AMAZING.

AS SOON AS THE WARM MILK REACHED HER STOMACH SHE

CALMED AS IF SHE RECOGNIZED THAT WE WERE

HERE TO HELP HER.

DYLAN: 14 MONTHS AFTER HER RESCUE J.J.

IS THRIVING; EATING 500 POUNDS OF SEAFOOD A DAY.

SOON SHE WILL BE RELEASED INTO THE WILD AND REJOIN

HER OWN KIND.

DYLAN: IN THE PROTECTED LAGOONS OF BAHA, CALIFORNIA,

ARRIVING WHALES ARE TREATED LIKE CELEBRITIES

BY ADORING FANS.

SHARI: MY LITTLE GIRL SIRENITA, THE LITTLE

MERMAID, HAS A VERY SPECIAL CONNECTION TO THE

WHALES.

SIRENA: WHEN I GOT OUT THERE IT WAS JUST LIKE

WHOA.

ONE WAS COMING STRAIGHT FOR US, I'M LIKE WHAT'S

THAT WHALE DOING? I WAS REALLY WISHING I WOULD

TOUCH A WHALE.

I'M LIKE OH, I HOPE I TOUCH HIM, AND ALL THE

SUDDEN MY HAND WAS REALLY DOWN.

SHARI: THEY SEEM TO REALLY STUDY US CAREFULLY.

I OFTEN WONDER WHAT THEY'RE THINKING ABOUT

WHILE THEY'RE GAZING AT US AS I GAZE AT THEM.

DYLAN: THE JOURNEY CONTINUES RIGHT AFTER

THIS.

ANNOUNCER: WE'LL BE RIGHT BACK TO THE MROE YOU KNOW ON NBC.

ANNOUNCER: WE NOW RETURN TO THE MORE YOU KNOW ON NBC.

DYLAN: ONE OF THE MOST BIZARRE MIGRATIONS IN

NATURE OCCURS ON TINY CHRISTMAS ISLAND, 1,000

MILES WEST OF AUSTRALIA IN THE INDIAN OCEAN.

A WORD OF WARNING, THIS NEXT STORY WILL PROBABLY

GIVE YOU GOOSEBUMPS.

DYLAN: CHRISTMAS ISLAND IS ONLY A LITTLE MORE THAN

50 SQUARE MILES, WITH A POPULATION UNDER 3,000

PEOPLE. BUT THERE'S ANOTHER CREATURE LIVING HERE AND

THEY NUMBER IN THE MILLIONS; THE RED CRAB.

EACH YEAR AS THE MONSOONS ARRIVE THE RAIN AND LUNAR

CYCLES COMBINE TO BEGIN THE BREEDING SEASON.

THESE LITTLE MONSTERS MAKE AN ANNUAL MARCH FROM THEIR

WOODLAND HOMES DOWN TO THE SEA TO MATE AND SPAWN.

[CAR HONKING]

DYLAN: UNFORTUNATELY MANY OF THE HUMAN INHABITANTS

OF CHRISTMAS ISLAND BUILD THEIR COMMUNITY SMACK IN

THE MIDDLE OF THE RED CRAB MIGRATION ROUTE.

THE CRABS ARE HARMLESS BUT THE ISLANDERS HAVE

DEVELOPED A STRAINED RELATIONSHIP WITH THEIR

FELLOW RESIDENTS OVER THE YEARS.

[CHILD SCREAMING]

[SCHOOL BELL]

DYLAN: AFTER A JOURNEY OF UP TO THREE WEEKS MALES

REACH THE SHORE FIRST.

WHEN THE FEMALES ARRIVE A FEW DAYS LATER THEY

PROMPTLY TAKE BATHS TO REPLENISH MOISTURE LOST ON

THE JOURNEY AND PERHAPS TO RINSE AWAY THE GRIME OF

TRAVEL AND ENHANCE THEIR FEMININE ALLURE.

AFTER MATING, MALES DEPART BACK TO THE FOREST.

FINALLY DURING HIGH TIDE OF THE LAST QUARTER MOON

FEMALES CARRY THEIR EGGS TO THE WATER'S EDGE AND

FLING THEM INTO THE OUTGOING TIDE.

THE EGGS DEVELOP INTO YOUNG CRABS THAT SPEND

THREE WEEKS OUT AT SEA.

SOON THE NEXT GENERATION WILL RETURN TO THE SHORE

AND WANDER BACK TO THE FOREST TO JOIN THEIR

PARENTS.

♪ MUSIC ♪

DYLAN: FROM BUTTERFLIES TO WHALES AND EVEN

MILLIONS OF CRABS, ANIMAL MIGRATIONS ARE A CRITICAL

COMPONENT OF THEIR SURVIVAL.

MOVEMENT IS LIFE.

I HOPE YOU ENJOYED OUR JOURNEY WITH THESE

MAGNIFICENT CREATURES.

AND UNTIL NEXT TIME, SAFE TRAVELS.

♪ MUSIC ♪