Original subtitles

\hTHERE IS A LEVIATHAN BELOW THAT FORGES ACROSS THE LAND.

\h\h\h\hITS TWISTS AND TURNS CARVE THROUGH THE LANDSCAPE

\h\hAND WEAVE THROUGH OUR NATION’S HISTORY.

IT IS THE MISSISSIPPI RIVER.

IT CONNECTS EAST TO WEST,

THE COUNTRY TO THE CITY... \h\h\h\h[SHIP HORN BLOWS]

AND AMERICA TO THE WORLD.

[SCREECHING]

♪

\h\h\hTO KNOW IT IS TO KNOW THE PROUD RHYTHM OF OUR LAND

AND THE NATURE OF OUR WILDLIFE.

♪

LIFE ALONG THE UPPER MISSISSIPPI

DANCES TO THE RHYTHMS \h\h\hOF THE RIVER...

A SYMPHONY CONDUCTED \h\h\hIN THE WILD...

[BELLOWING]

...ON A STAGE WITH MANY PLAYERS.

ITS SCORE BEGINS GENTLY,

THEN BUILDS TO A CRESCENDO.

[GROWLING]

[BELLOWING]

THIS IS THE OPENING ACT

OF A GREAT JOURNEY

DOWN AMERICA’S RIVER.

♪

♪

OUR STORY BEGINS AT A LAKE.

\h\hIT SITS IN THE LAND OF TEN THOUSAND LAKES--

MINNESOTA.

JUST A FACE IN THE CROWD, \h\hEXCEPT FOR ONE THING--

\h\h\h\hIT IS THE BIRTHPLACE OF AMERICA’S GREATEST RIVER.

♪

THE CHIPPEWA NAMED IT ELK LAKE,

BUT THE ELK WERE HUNTED OUT \h\h\h\h\h\h\h\h\hLONG AGO.

♪

NOW IT BEARS THE NAME ITASCA,

\h\h\h\h\h\h\hLATIN OF SORTS FOR TRUE HEAD OF THE RIVER.

♪

IN THE FAR NORTHEAST CORNER \h\h\h\h\h\h\h\hOF THE LAKE,

ITS OVERFLOW FORMS A STREAM \h\h\hJUST 25 FEET ACROSS...

BARELY A HINT OF WHAT \h\h\hIT WILL BECOME.

♪

WHATEVER BABBLES OVER THESE ROCKS

IS INSTANTLY BAPTIZED ANEW.

NO LONGER ITASCA,

NOW THE MISSISSIPPI RIVER.

♪

IT FORGES ITS WAY THROUGH \h\h\hTHE HEART OF AMERICA

FOR 2,300 MILES

BEFORE IT SPILLS INTO \hTHE GULF OF MEXICO.

ALONG THE WAY IT DRAWS WATER \h\h\h\h\hFROM 31 STATES...

\h...DRAINING MORE THAN A MILLION SQUARE MILES.

♪

NOWHERE IS MISSISSIPPI COUNTRY \h\h\h\h\h\h\h\h\h\hMORE WILD

THAN HERE IN MINNESOTA \h\h\hWHERE IT BEGINS.

♪

\h\hIT WINDS NORTH THROUGH WILDERNESS

\h\h\hAT A LEISURELY 1.2 MILES AN HOUR--

BARELY HALF THE SPEED \hOF A MORNING STROLL.

THIS WATERSHED IS WHERE NATURE HUMS AND BUZZES.

[BIRDS CHIRPING]

[DUCKS QUACKING]

A MOTHER MOOSE BRINGS HER CALVES TO THE WATER FOR TWO REASONS--

SAFETY AND FOOD.

THE RIVER IS AN ESCAPE ROUTE FROM PREDATORS LIKE WOLVES,

AND IT PROVIDES A FEAST.

\h\hSUBMERGED WATER LILIES HELP THEM PACK ON WEIGHT.

MOM CAN EAT UP TO \h60 POUNDS A DAY.

♪

[BELLOWING]

\h\h\h\h\h\hIT’S FALL, AND SHE’S READY TO MATE AGAIN.

[BELLOWING]

\hHER BELLOWS SUMMON A BULL FROM THE COOLER HIGH GROUND.

[BELLOWING]

HE’S NOT THE ONLY ONE \h\h\hWITHIN EARSHOT.

[SNORTS]

THE RESIDENT CHAMP HAS A CHALLENGER.

OCTOBER IS THE RUT.

A FIGHT IS COMING.

♪

IN SPRING THEIR RACKS \h\hWERE NOTHING MORE

THAN SMALL, SOFT NUBS,

BUT ANTLERS GROW FASTER THAN \hANY OTHER MAMMALIAN BONE.

NOW THEY ARE 40-POUND \h\h\hBATTERING RAMS.

♪

♪

[GRUNTING]

\h\h\hTHE BULLS POSTURE AND SIZE EACH OTHER UP.

IT’S A LAST CHANCE TO BACK DOWN.

BUT NEITHER TAKES IT.

♪

♪

A DIRECT HIT CAN BLIND, MAIM, \h\h\h\h\h\h\h\h\h\hEVEN KILL.

♪

♪

[GRUNTING]

THIS KING’S CROWN FITS WELL.

\h\h\h\h\hHE’LL KEEP HIS PATCH OF THE MISSISSIPPI WATERSHED.

THE CHALLENGER MOVES ON TO TRY \hHIS LUCK FARTHER DOWNSTREAM.

[BIRDS CHIRPING]

♪

THE RIVER SOON TURNS EAST.

[CAW]

THEN, JUST 40 MILES FROM ITASCA, A NEW TWIST.

\hNATURE’S ENGINEERS HAVE BEEN VERY BUSY.

♪

TWO BEAVERS PREPARE FOR WINTER.

♪

\h\hTHE COUPLE MUST STORE ENOUGH FOOD IN THEIR LODGE

TO GET THEM THROUGH FOUR MONTHS OF BITTER COLD.

♪

THEY HAVE HUNGRY MOUTHS TO FEED.

THE THREE KITS ARE \hFOUR MONTHS OLD.

THEY WERE WEANED WEEKS AGO.

NOW THEY EAT THE SOFT \hINNER LAYER OF BARK.

[MOANING]

THEIR DAM KEEPS THE WATER HIGH,

WHICH STOPS THEIR ENTRANCE \h\h\hFROM FREEZING OVER.

\h\h\hBUT IT REQUIRES CONSTANT MAINTENANCE.

THE PARENTS WORK 20 HOURS A DAY, ALL THROUGH THE NIGHT.

♪

[SCRAPING]

♪

A BEAVER FAMILY WILL FELL AROUND A HUNDRED TREES EVERY FALL,

AN ANNUAL RACE TO BUILD UP \hTHEIR DAM BEFORE WINTER.

♪

EARLY SETTLERS CAME HERE TO TRAP BEAVERS BY THE THOUSAND,

DRIVEN BY A LUCRATIVE FUR TRADE.

♪

AS RECENTLY AS 1976,

HALF A MILLION BEAVERS WERE \hKILLED IN A SINGLE SEASON.

MOST OF THOSE VALUABLE PELTS \hMADE THEIR WAY TO MARKET,

\h\h\h\h\h\h\hSHIPPED SOUTH DOWN THE MISSISSIPPI RIVER.

♪

BEAVERS ARE SECOND \h\hONLY TO HUMANS

IN THEIR ABILITY TO MANIPULATE AND CHANGE THEIR ENVIRONMENT.

BUT SOON THIS YOUNG RIVER \h\h\hWILL BE A CHALLENGE

TO MAN AND BEAST ALIKE.

\hA POWERFUL FORCE AND FROZEN THICK.

80 MILES FROM LAKE ITASCA,

\h\hTHE MISSISSIPPI RIVER PICKS UP VOLUME AND TEMPO

AS IT CARVES THROUGH MINNESOTA.

♪

AS FALL GROWS OLD, \hTHE WINDS BITE.

[BIRD SCREECHES]

NIGHTS GROW LONGER.

♪

\h\h\h\hTIME IS RUNNING OUT TO STORE FOOD AND FATTEN UP.

♪

A RACCOON FINDS TREASURE \hIN A RIVERSIDE PARK--

\h\h\h\hA FATTENING PICNIC OF PEANUTS AND LEFTOVERS.

BUT HE’S NOT ALONE.

[GRUNTING]

[RACCOON CHATTERING]

[BEARS GRUNTING]

A BLACK BEAR’S SENSE OF SMELL IS TEN TIMES THAT OF A DOG’S,

\h\hAND THEY’LL EAT JUST ABOUT ANYTHING.

NUTS, BUGS, BERRIES, OR MEAT.

\h\hTHEIR DIVERSE DIET IS ONE OF THE KEYS TO THEIR SUCCESS.

THE RACCOON’S WINDFALL \h\hWILL DO JUST FINE.

EASY COME...

[GROWLING]

EASY GO.

[RACCOON CHATTERING]

[BEAR GROWLING]

\h\h\hTHE STOLEN STASH HELPS ADD INCHES TO THEIR BELLIES.

\h\h\h\h\hEVERY BITE COUNTS AS THEY PREPARE FOR A DEEP SLEEP

AND AN ANNUAL FAST THAT MAY LAST AS LONG AS SEVEN MONTHS.

♪

200 MILES FROM ITASCA,

\hTHE RIVER STILL FLOWS EAST TOWARD THE WISCONSIN BORDER.

[MOOSE BELLOWS]

MOST NIGHTS THROUGH NOVEMBER,

THE TEMPERATURE SINKS \h\h\hBELOW FREEZING.

\hBY THE END OF THE MONTH, EVEN THE DAYS GROW FRIGID.

♪

AND THEN IT COMES.

♪

[WIND HOWLING]

DECEMBER HITS HARD.

[QUACKING]

♪

NATIVE AMERICANS HUNKERED DOWN \h\h\h\h\h\h\h\h\hIN MINNESOTA

IN WINTER HUNTING CAMPS.

THEY FACED TEMPERATURES \h50 DEGREES BELOW ZERO

WITH NOTHING MORE THAN \h\hDEERSKIN CLOTHING

AND WIGWAMS MADE FROM \h\hIRONWOOD SAPLINGS.

ANIMALS MUST ALSO ADAPT.

[HONKING]

\h\hTHOSE WITH WINGS CAN SIMPLY ESCAPE THE COLD.

AND THEY DO SO EN MASSE.

MORE THAN 325 BIRD SPECIES \h\h\h\hPASS THROUGH HERE

ON THEIR WINTER MIGRATION \h\h\h\h\h\h\h\h\hSOUTH--

60% OF ALL NORTH AMERICAN BIRDS.

\h\h\h\h\h\hIT’S CALLED THE MISSISSIPPI FLYWAY.

BUT THE FREEZE COMES FAST \h\h\h\h\h\hIN MINNESOTA.

SOME WATERBIRDS MUST SUDDENLY \h\h\h\h\h\hCONTEND WITH ICE.

[QUACKING]

♪

\h\h\h\hABOVE THEM, AMERICA’S NATIONAL BIRD, THE BALD EAGLE,

RULES THE SKY.

[CHIRPING]

[QUACKING]

[CHIRPING]

WHEN THE ICE SURROUNDS \h\h\hTHE STRAGGLERS,

DEADLY TALONS SWOOP DOWN.

♪

ALL A DUCK CAN DO IS... \h\h\h\h\h\hWELL, DUCK.

♪

♪

[QUACKING]

♪

JUVENILE EAGLES LEARN \h\h\h\hTO HUNT HERE.

\h\h\h\h\hTHEY GO FOR THE SEASONAL SPECIAL.

CANVASBACK DUCKS, SLIGHTLY CHILLED.

[QUACKING]

♪

[QUACKING]

♪

♪

[SCREECHING]

[CHIRPING]

[QUACKING]

[CHIRPING AND QUACKING]

♪

IT’S WINNER TAKES ALL.

♪

\hAND THERE’S NO ESCAPE FROM THE MISSISSIPPI’S NUMBER ONE RAPTOR.

♪

[CHIRPING]

FROM WHERE IT BEGAN,

THE MISSISSIPPI HAS \h\hTRAVELED NORTH,

THEN EAST FOR ABOUT 160 MILES.

\h\h\h\h\h\h\h\hNOW NEAR GRAND RAPIDS, MINNESOTA,

THE RIVER FINALLY TURNS SOUTH.

\hTHE MISSISSIPPI IS 100 FEET WIDE HERE.

YET BY JANUARY, IT CAN BE \hENTIRELY ENCASED IN ICE.

♪

SOME MAY VENTURE ACROSS.

♪

ALONG ITS BANKS,

THE BRUTAL COLD AND FRIGID WINDS WEED OUT THE WEAK.

[CAWING]

A HARSH WINTER CAN FELL \h\h\h\hONE IN TEN DEER.

IT’S AN OPPORTUNITY \hFOR SCAVENGERS...

AND PREDATORS.

WHEN THE WIND BLOWS RIGHT,

WOLVES CAN SMELL DEATH FROM OVER A MILE AWAY,

AND THEY CAN EASILY COVER THAT \hDISTANCE WITHIN TEN MINUTES.

\hTODAY, THERE ARE MORE THAN 400 WOLF PACKS IN MINNESOTA.

\h\h\h\hCOMPETITION AROUND THE MISSISSIPPI IS FIERCE.

THIS PACK HAS BEEN HUNTING \h\h\hIN THE AREA FOR DAYS

WITHOUT A KILL.

THE CARCASS COULD FEED THEM FOR A WEEK--IF THEY CAN REACH IT.

♪

[WHIMPERING]

♪

\h\h\h\h\h\hTHEY MAY BE THE TOP PREDATORS HERE,

BUT ONE MISSTEP THROUGH THE ICE

COULD BE THEIR OWN \hDEATH SENTENCE.

[CAWING]

[GROWLS]

[WHIMPERING]

[GRUNTS]

CAUTION IS A VIRTUE.

♪

[BIRD SQUAWKING]

♪

SO IS VALOR.

♪

[GROWLS]

SUCCESS.

♪

RETRIEVING THE PRIZE \h\h\hIS ONE THING;

KEEPING IT IS ANOTHER.

♪

[SNARLING]

\h\h\hEVERYONE GETS A SHARE, BUT ALPHAS ALWAYS EAT FIRST.

[GROWLING]

[SNARLING]

[CROW CAWING]

THE INCH-LONG CANINES TEAR FLESH AND SORT OUT THE HIERARCHY.

♪

THERE’S A STRICT PROTOCOL \h\h\h\h\h\h\hFOR DINING.

♪

\h\h\h\hWOLF POPULATIONS IN THE UPPER MISSISSIPPI

WERE NEARLY WIPED OUT \h\h\h\hA CENTURY AGO.

NOW THEIR NUMBERS GROW AND THEY MOVE FURTHER SOUTH EACH YEAR.

♪

\h\h\h\h\h\h\hBY MID-WINTER, ICE CLOSE TO TWO FEET THICK

WEIGHS HEAVY ON THE RIVER.

♪

WHEN SPRING COMES,

IT’LL TAKE A FULL MONTH OF WARM WEATHER TO THAW.

♪

AN EARLY GLIMPSE OF SUN

ENTICES A YOUNG BLACK BEAR \h\h\h\h\hOUT OF HIS DEN.

♪

THE TIME FOR HIS DEEP WINTER \h\h\hSLEEP ISN’T OVER YET,

BUT THE EAGER TWO-YEAR-OLD \h\h\hCAN’T HELP HIMSELF.

♪

HE VENTURES OUT, HOPING FOR \h\h\h\hA LATE-WINTER SNACK.

♪

♪

IT’S TOO SOON.

THE SNOW IS STILL TOO DEEP,

NOT WORTH THE TROUBLE.

[GROWLS]

MOM STIRS TO CALL HIM \h\h\h\h\hBACK TO BED.

[GRUNTING]

[GRUNTING]

♪

♪

WINTER’S SONG IS NOT YET THROUGH.

♪

♪

AND SOME ARE READY FOR THAT.

♪

[SNIFFING]

A LONG-TAILED WEASEL STILL \h\hWEARS HIS WINTER COAT.

♪

HE CATCHES THE SCENT \h\hOF FRESH MEAT--

A DEER MOUSE.

HE’S AN AMBUSH HUNTER AND RELIES ON THE ELEMENT OF SURPRISE.

♪

♪

♪

TOO LATE.

\h\hBLOW THE SURPRISE, AND YOU BLOW THE MEAL.

BUT NOT TO WORRY,

HE KEEPS A FOOD STASH FOR WHEN \hFRESH MEAT IS HARD TO FIND.

MOST WEASELS WON’T EAT ANIMALS \h\h\h\h\h\hKILLED BY OTHERS,

SO THEY STORE THEIR OWN.

WITH SMALL PREY LIKE THIS RAT,

HE’LL EVENTUALLY EAT IT ALL--

FLESH, FUR, BONE, AND TAIL.

♪

\hTHE MELODY OF WINTER HAS PLAYED OUT ALONG THE RIVER

FOR 300 MILES.

NOW SPRING BRINGS A DIFFERENT TUNE,

\hAS NEW MEMBERS OF NATURE’S ORCHESTRA COME OUT TO PLAY.

♪

[BEAR GRUNTING]

♪

EACH NEW DAY IN MARCH

\h\h\hBRINGS AN ADDITIONAL THREE MINUTES OF DAYLIGHT.

THE GREAT MISSISSIPPI MELT \h\h\h\h\h\h\h\h\hBEGINS.

♪

♪

\h\h\hTHE THAW REVEALS A WELCOME SURPRISE...

FROZEN FOOD.

♪

A FEW GIZZARD SHAD GET TRAPPED \h\h\h\hIN THE ICE EVERY YEAR,

BUT THIS TIME IS SPECIAL.

AN UNUSUALLY FAST FREEZE BACK IN DECEMBER CAUGHT THOUSANDS.

[SQUAWKING]

GULLS FLY IN FROM \hTHE GREAT LAKES

TO ENJOY THE FEAST.

[SQUAWKING]

IT DOESN’T GET ANY BETTER \h\h\h\h\hFOR A SCAVENGER.

[SQUAWKING]

EXCEPT THE GULLS HAVE ENTERED \h\h\h\hSOMEONE ELSE’S DOMAIN.

[SQUAWKING]

AMERICA’S RIVER BELONGS \h\h\hTO THE BALD EAGLE.

TRESPASSERS BEWARE.

[CHIRPING]

♪

[CHIRPING AND SQUAWKING]

♪

BALD EAGLES STAKE THEIR CLAIM \h\h\hTO THE MISSISSIPPI RIVER

AND ITS FEAST OF DEFROSTED FISH.

♪

[SQUAWKING]

\h\h\hGULLS MUST YIELD TO THE MORE POWERFUL RAPTORS.

♪

[CHIRPING]

♪

♪

♪

♪

THE GORGING CONTINUES \h\h\hTHROUGHOUT MARCH

WHILE THE ICE SLOWLY \hRELEASES ITS HOLD.

[GULLS SQUAWKING]

[CRACKLING]

\h\h\hA MISSISSIPPI LONG GRIPPED BY ICE

\h\h\h\h\h\hSHAKES LOOSE THE SHACKLES OF WINTER.

\hIT GUZZLES THE SNOWMELT AND ONCE AGAIN RUNS FREE AND FAST.

♪

HUNDREDS OF MILLIONS OF GALLONS OF MELTED ICE AND SNOW

SURGE THROUGH MINNESOTA \h\h\h\h\h\h\hIN SPRING.

♪

\hTHE BEAVER’S DAM WASHES DOWNSTREAM WITH THE FLOOD.

THEY MUST BUILD AGAIN.

EVEN THE KITS PITCH IN.

THE BEAVERS ARE VULNERABLE \h\h\h\h\hWITHOUT SHELTER,

AND AT ANY SIGN OF TROUBLE

THEY SPLASH AN ALARM TO WARN THE FAMILY.

♪

♪

\h\h\h\hOTHERS ARE UNFAZED BY THE RISING MISSISSIPPI

AND RELISH THE SPRING SURGE.

♪

SPRING MEANS NEW GROWTH...

NEW BABIES...

AND FOR ONE CREATURE,

A SPECTACULAR CHANGE \h\h\h\hIN WARDROBE.

[BIRDS CHIRPING]

♪

THE LONG-TAILED WEASEL SPROUTS A NEW FUR COAT

TO MATCH THE SEASON.

THE NEW COLOR MAKES IT EASIER FOR HIM TO HIDE FROM PREDATORS

AND SNEAK UP ON PREY.

♪

THE MEADOW VOLE WOULD BE SAFE IN HIS BURROW FROM MOST PREDATORS--

BUT NOT THIS ONE.

♪

♪

[SNIFFING]

♪

[SQUEAKING]

HE KILLS WITH PRECISION.

\h\h\h\hA CRUSHING BITE TO THE BACK OF THE NECK,

SEVERING THE SPINAL CORD.

THIS APPETITE FOR RODENTS

\h\h\h\hMAKES WEASELS A FRIEND TO THE MISSISSIPPI’S FARMERS.

THEY’RE CRUCIAL IN CONTROLLING \hTHE NUMBER OF MICE AND RATS

THAT INFEST CROPS.

♪

450 MILES FROM WHERE IT BEGAN,

FARMS LINE THE BANKS \h\h\hOF THE RIVER.

IT’S STILL IN MINNESOTA,

WITH ALMOST 200 MILES \h\h\h\h\hLEFT TO GO.

JUST AROUND THE BEND, THE RIVER REACHES ITS FIRST MAJOR CITY,

MINNEAPOLIS.

♪

\hA COMPLEX SYSTEM OF LOCKS AND DAMS

KEEPS THE MELTING MISSISSIPPI \h\h\h\h\h\h\h\h\h\hIN CHECK.

♪

\h\h\hTHIS IS AS CLOSE AS THE MISSISSIPPI EVER GETS

TO HAVING A WATERFALL.

♪

AS THE RIVER LEAVES THE CITY, \h\h\h\h\h\h\hIT GETS A BOOST.

\h\h\hTHE MURKY WATERS OF THE MINNESOTA RIVER

FLOW IN FROM THE WEST.

DAKOTA SIOUX INDIANS NAMED IT \h\h\h\h\h\h\h\h\hMINNI-SOTAH,

MEANING "CLOUDY WATER."

♪

\h\h\hON THE EASTERN BANK LIES THE CITY OF ST. PAUL.

\h\h\h\h\hBUT DON’T LET THIS URBAN DEVELOPMENT FOOL YOU.

THE WILD SIDE OF THE MISSISSIPPI IS NOT OVER YET.

♪

JUST OUT OF THE TWIN CITIES,

THE MISSISSIPPI PICKS UP \hTHE SAINT CROIX RIVER,

AND OTHER TRIBUTARIES \h\hBEGIN POURING IN.

AS IT FLOWS ALONG THE BORDER \h\h\h\h\h\hWITH WISCONSIN,

THE RIVER QUICKLY BECOMES \h\h\h\h\h\hTHE JUGGERNAUT

\hTHAT WILL ULTIMATELY DRAIN 40% OF THE LOWER 48 STATES.

♪

♪

FOR ALL THE LOCKS AND DAMS,

THIS WATERSHED IS STILL \h\h\hA FORCE OF NATURE.

♪

AND NATURE CLINGS TO IT \h\h\h\h\hFOR SURVIVAL.

ENORMOUS STURGEON HAVE INHABITED THE MISSISSIPPI RIVER WATERSHED

FOR TENS OF THOUSANDS OF YEARS.

THESE PREHISTORIC FISH \h\h\h\hARE AS MIGHTY

AS THE RIVER THAT HOLDS THEM.

\h\h\h\hSTURGEON CAN GROW MORE THAN SEVEN FEET LONG,

WEIGH MORE THAN 200 POUNDS,

AND THE FEMALES CAN LIVE \h\h\h\h\hFOR 150 YEARS.

EVERY SPRING THEY SURGE \h\h\hUPRIVER TO SPAWN.

WHEN THEY CAN’T SWIM \h\h\h\hANY FARTHER,

THEY FIND CALM WATER NEARBY.

♪

♪

\h\h\h\h\h\hFEMALES EMIT INFRASONIC MATING CALLS,

\h\h\hWHICH ATTRACT A CROWD OF MALES...

♪

♪

...THEN RELEASE HUNDREDS \hOF SMALL, ROUND EGGS.

♪

THE MALES RELEASE THEIR SPERM

\h\h\h\h\hAND FERTILIZE THE MISSISSIPPI RIVER’S

\h\h\hNEXT GENERATION OF PREHISTORIC GIANTS.

♪

CREATURES OF ALL SHAPES AND SIZES

RELY ON THE MISSISSIPPI RIVER.

SO DO PEOPLE.

AS IT FLOWS AND GROWS,

IT BECOMES AMERICA’S LIFELINE \h\h\h\h\h\h\h\hTO THE WORLD.

THE RIVER CARRIES MORE THAN HALF OF OUR GRAIN EXPORTS TO MARKET.

♪

WE RIDE IT, SHAPE IT,

AND BUILD BRIDGES OVER IT.

IT CONNECTS US TO COMMERCE \h\h\h\h\h\h\hAND NATURE.

THE OLD I-90 BRIDGE IN DRESBACH, SOUTHERN MINNESOTA,

\h\hHAS BEEN HOME TO AS MANY AS 4,000 LITTLE BROWN BATS.

\hTHE BRIDGE’S SMALL, COVERED CREVICES FORM A PERFECT ROOST

\hAND ALLOW QUICK ACCESS TO THE INSECTS SWARMING OVER THE RIVER.

NOW THE BRIDGE HAS TO COME DOWN.

\h\h\h\h\h\hBUT IF THE BATS GO, THE INSECT POPULATION WILL RISE.

[BATS SQUEAKING]

BATS EAT HALF THEIR BODY WEIGHT IN BUGS EVERY NIGHT.

THAT’S 1,200 INSECTS \h\hAN HOUR PER BAT!

♪

THE SOLUTION--BAT CONDOS.

STATE OFFICIALS BUILT THE COLONY A NEW HOME,

WITH A RIVERSIDE VIEW.

♪

[BATS SQUEAKING]

♪

[CHIRPING]

♪

[CHIRP]

BATS AREN’T THE ONLY CREATURES \h\h\h\h\h\hON THE MISSISSIPPI

WHO FEAST AT NIGHT.

\h\h\hAS THE RIVER WINDS THROUGH POPULATED AREAS,

IT FAVORS ANIMALS THAT USE \h\hTHE COVER OF DARKNESS.

A NORTHERN WATER SNAKE VENTURES OUT AFTER A DAY SPENT SLEEPING.

IT’S NON-VENOMOUS, BUT FAST.

♪

WHEN THE SUN GOES DOWN,

IT HEADS INTO THE RIVER TO HUNT FOR ITS FAVORITE FOOD--

FISH.

♪

IT CAN HOLD ITS BREATH FOR UP TO 90 MINUTES.

♪

AND IT’S EXTREMELY PATIENT.

♪

♪

♪

ITS VISE-LIKE JAWS TIGHTEN,

AND THIS NIGHT HUNTER \h\h\h\hHAS ITS FILL.

♪

♪

♪

\h\hTHE RIVER PREPARES TO EXIT MINNESOTA AND THE GREAT NORTH.

\hBUT IT HAS ONE LAST GIFT TO OFFER ON THE BORDER...

♪

A FEAST ON A BIBLICAL SCALE...

THE GRAND FINALE OF SUMMER.

♪

\h\hAFTER TWO YEARS FORMING ON THE BOTTOM OF THE GREAT RIVER,

\h\h\hAN ENORMOUS SWARM WAKES FROM HIBERNATION.

♪

BILLIONS OF ADULT MAYFLIES RISE FROM THE MISSISSIPPI.

\h\h\hTHEY OPEN THEIR WINGS FOR THE FIRST AND LAST TIME.

♪

\hIT IS THE FOURTH OF JULY, AND THIS IS THEIR INDEPENDENCE DAY.

\h\hTHEY WILL LIVE ONLY TILL MORNING.

♪

\h\h\h\h\hTHE BANKS OF THE UPPER MISSISSIPPI

ARE HOME TO THE WORLD’S \hLARGEST MAYFLY HATCH.

♪

♪

BILLIONS OF THESE INCH-LONG INSECTS

SWARM IN A SEXUAL FLURRY.

\h\h\h\hTO A WEATHER SATELLITE IT LOOKS LIKE A THUNDERSTORM.

A ONE-DAY-A-YEAR DELUGE.

♪

BY NIGHTFALL, IT’S ALMOST OVER.

ONCE THEY’VE MATED,

FEMALES DESCEND INTO THE RIVER \h\h\h\hTO DEPOSIT THEIR EGGS,

EACH LAYING UP TO ONE THOUSAND.

THEY HAVE LIVED A LIFETIME \hIN JUST ONE CROWDED DAY.

\h\h\hNOW THE FRENZY FADES AS MALES AND FEMALES ALIKE

UNWITTINGLY COMMIT THEIR BODIES TO THE GREAT BOUNTY OF SUMMER.

♪

[BIRD SQUAWKING]

ALL-YOU-CAN-EAT MAYFLIES,

\h\h\h\h\hCOURTESY OF THE MISSISSIPPI RIVER.

♪

\hTHE RIVER LEAVES MINNESOTA BEHIND,

\h\hAND HEADS INTO IOWA AND ILLINOIS.

♪

THE NORTHERN SYMPHONY ENDS,

AND A NEW TUNE BEGINS, \h\h\hLOUD AND PROUD.

♪

FROM HERE ON DOWN, THE RIVER DANCES TO A DIFFERENT TUNE.

♪

THE MISSISSIPPI IS READY TO ROAR INTO AMERICA’S HEARTLAND.

♪