Original subtitles

Wade: I'M JEREMY WADE,

EXTREME ANGLER AND FRESHWATER DETECTIVE.

I'VE BEEN HEARING STORIES OF A SHADOWY PREDATOR

HIDING IN AN AUSTRALIAN RIVER

THAT'S THICK WITH DEADLY FLESH EATERS.

IT WAS ONLY NAMED A FEW YEARS AGO,

IT'S NEVER BEEN FILMED,

AND NEXT TO NOTHING IS KNOWN ABOUT IT.

AND I'M SETTING OUT TO ATTEMPT THE NEAR IMPOSSIBLE --

TO CATCH ONE.

AGAINST MILLION-TO-ONE ODDS, THIS JOURNEY WILL EXPAND

OUR KNOWLEDGE OF THE FRESHWATER WORLD

AND TURN WHAT I THOUGHT I KNEW ABOUT RIVER KILLERS

UPSIDE DOWN.

LOOK AT THAT. LOOK AT THAT. LOOK AT THAT.

[ INSECTS, BIRDS CHIRPING ]

LAST YEAR, I TRAVELED TO AUSTRALIA'S FITZROY RIVER,

ONE OF THE MOST EXTREME AND LEAST-EXPLORED WATERWAYS

ON THE PLANET

AND ONE RENOWNED FOR ITS MAN-EATERS.

I DISCOVERED THAT TWO OF ITS MOST IMPRESSIVE PREDATORS

WERE INTERLOPERS SWIMMING IN FROM THE SEA.

GOT SOMETHING ON THERE.

ONE LOOKED MURDEROUS, BUT IT'S A GENTLE GIANT.

OH, IT'S A SAWFISH. IT'S A SAWFISH.

THE OTHER IS A KNOWN KILLER -- THE BULL SHARK.

BUT I ALSO HEARD RUMORS

OF ANOTHER PREDATOR SWIMMING IN FROM THE OPEN OCEAN,

ONE SO ELUSIVE, IT WAS ONLY DISCOVERED 10 YEARS AGO,

SO MYSTERIOUS, NEXT TO NOTHING IS KNOWN ABOUT IT,

AND SO RARE THAT ONLY A HANDFUL HAVE EVER BEEN CAUGHT --

THE GLYPHIS SHARK.

MORE PEOPLE HAVE WALKED ON THE MOON

THAN HAVE CAUGHT THIS FISH ON ROD AND LINE,

BUT I'VE NOT BEEN ABLE TO FORGET ABOUT IT,

SO I'VE COME BACK TO WESTERN AUSTRALIA

TO SEE IF I CAN CATCH THIS VERY RARE FISH

AND FIND OUT IF IT'S A POTENTIAL KILLER.

I START BY MEETING UP WITH AN OLD CONTACT.

AMERICAN FISH SCIENTIST JEFF WHITTY WORKS ON THE FITZROY.

HOW'S IT GOING?

I'VE FISHED WITH HIM BEFORE,

AND HE'S ONE OF THE FEW PEOPLE TO HAVE EVER SEEN A GLYPHIS.

WHAT CAN JEFF TELL ME ABOUT THE FISH I'M HERE TO CATCH?

THEY'RE A PRETTY RARE SHARK.

THEY WERE ONLY DISCOVERED HERE IN WESTERN AUSTRALIA

IN LIKE 2002.

AND SINCE THEN WE'VE CAUGHT VERY FEW,

KNOW VERY LITTLE ABOUT THIS FISH.

FEWER THAN 20 GLYPHIS RIVER SHARKS HAVE EVER BEEN CAUGHT,

FROM JUST A HANDFUL OF RIVERS IN AUSTRALIA AND NEW GUINEA.

NO FULL-GROWN ADULTS HAVE EVER BEEN RECORDED,

BUT THEY ARE THOUGHT TO GROW OVER 9 FEET LONG.

BEYOND THAT, THEIR RANGE, POPULATION SIZE, AND BEHAVIOR

ARE SHROUDED IN MYSTERY.

AND NO ONE KNOWS JUST HOW DANGEROUS THESE FISH ARE.

THAT'S WHERE I COME IN.

ANY CHANCE OF ONE THESE THINGS PICKING OUR BOAT UP?

LIKELIHOOD -- VERY RARE SPECIES,

EVEN SO MUCH THAT THEY'RE LISTED AS CRITICALLY ENDANGERED.

THERE'S ALWAYS A CHANCE.

THAT'S WHAT'S FUN ABOUT FISHING. THERE'S ALWAYS A CHANCE.

BUT IT'S A RARE CHANCE.

IF I DO MANAGE TO GET ONE IN THE NEXT FEW DAYS,

PRESUMABLY, THAT'S GONNA BE QUITE A SIGNIFICANT ADDITION

TO, YOU KNOW, THE DATA.

VERY FEW HAVE BEEN CAUGHT IN WESTERN AUSTRALIA -- PERIOD.

SO INCREASING THAT SAMPLE SIZE BY EVEN ONE

WOULD BE A MASSIVE CONTRIBUTION.

I'M TRYING TO CATCH A FISH THAT FEW PEOPLE HAVE EVER SEEN

IN A RIVER THAT RUNS FOR NEARLY 300 MILES.

AND I HAVE JUST TWO WEEKS TO DO IT.

I MUST BE CRAZY.

ON MY LAST TRIP, I LEARNED THAT THE FITZROY

DRAWS SOME FISH IN FROM THE SEA.

BOTH BULL SHARKS AND SAWFISH USE ITS WATERS

AS A PLACE TO GIVE BIRTH TO THEIR LIVE YOUNG.

THIS IS PROBABLY ABOUT A YEAR OLD.

THERE HAVE TO BE BREEDING-SIZE ADULTS AROUND.

IT'S POSSIBLE THE GLYPHIS DOES THE SAME.

THAT GIVE ME SOMETHING TO GO ON.

THE FITZROY RUNS THROUGH

ONE OF THE WORLD'S LAST GREAT WILD PLACES --

ISOLATED, UNDISTURBED, AND HOSTILE.

IT'S SAID THERE ARE SO MANY FLESH EATERS IN THE WATER

THAT WHEN PEOPLE GO MISSING, THEIR BODIES ARE NEVER FOUND.

AND I'VE HEARD OF ONE UNSOLVED ATTACK

THAT MIGHT JUST ADD THE GLYPHIS

TO THIS LIST OF HOSTILE RIVER MONSTERS.

IT WAS A SUMMER EVENING, AT THE HEIGHT OF A HEAT WAVE.

A YOUNG MAN CAME DOWN TO THE RIVER TO COOL OFF.

JUST A FEW YARDS OUT,

HE FELT SOMETHING TEAR INTO HIS FLESH.

HE DRAGGED HIMSELF BACK TO SHORE,

WHERE HE SAW A SAVAGE GASH IN HIS THIGH.

[ MAN GROANING ]

I'M TOLD THE VICTIM SURVIVED,

BUT HIS ATTACKER HAS NEVER BEEN IDENTIFIED.

IT SOUNDS LIKE THE WORK OF A FRESHWATER SHARK,

AND THE GLYPHIS I'VE COME TO CATCH MIGHT JUST BE A SUSPECT.

FROM THE CHOPPER,

I MAP OUT THE BEST-LOOKING FISHING HOLES,

THE DANGER ZONES, AND THE ESCAPE ROUTES.

BECAUSE AS SOON AS I HIT THE GROUND,

I'M FISHING MANY MILES FROM THE NEAREST HOSPITAL.

I NEED TO STAY OUT OF RANGE OF THE KILLERS I CAN SEE

AND THE HIDDEN PREDATORS I CAN'T.

I'M USING DEAD FISH BAIT,

A LARGE HOOK, AND A WIRE TRACE --

PERFECT FOR TOOTHY HUNTERS IN MUDDY WATER.

THAT'S A FISH, I THINK.

WHAT IS IT? OH, THAT IS A CRAB. THAT IS A CRAB.

THE BOTTOM RUNG ON THE FLESH-EATING LADDER,

THESE RIVER CRABS CLEAN UP ANYTHING

THE LARGER PREDATORS MISS.

SO, THAT'S WHAT THEY DO.

I MEAN, YOU'RE LEFT FISHING WITH NO BAIT.

BUT THEY'RE NOT THE ONLY TECHNICAL CHALLENGE.

THIS FISHING IS ACTUALLY VERY PROBLEMATICAL.

THERE'S ALL THIS STUFF ON THE TOP OF THE WATER

CATCHING MY LINE.

THERE'S RUBBISH ON THE BOTTOM AS WELL.

I'M JUST GETTING SNAGGED UP, LOSING SO MUCH STUFF.

ANYWHERE ELSE IN THE WORLD, I'D GET IN TO RETRIEVE MY GEAR.

BUT HERE, IT'S TOO RISKY.

JUST GETTING A BAIT IN POSITION

WHERE IT'S LIKELY TO INTERCEPT SOMETHING MORE INTERESTING

IS REALLY QUITE A CHALLENGE.

ANY FISH LIVING IN THIS PREDATOR SOUP

NEEDS TO BE CONSTANTLY ALERT.

WELL, THE BAIT IS GONE.

AND WHEN THEY'RE ALL WATCHING THEIR BACKS,

THEY'RE HARDER TO CATCH.

THIS IS GOING OUT.

BUT THE NEXT MORNING,

SOMETHING AT LAST LETS ITS GUARD DOWN.

I'LL LET IT PLAY WITH IT A BIT MORE.

IT SEEMS TO BE QUITE HESITANT.

OKAY. I'M GONNA HIT THIS.

YEP. THERE WE GO.

OKAY. I'M GONNA HIT THIS.

ON AUSTRALIA'S FITZROY RIVER, I'VE HOOKED INTO A FISH.

YEP. THERE WE GO.

BUT IS IT A GLYPHIS?

OH, IT'S A SHARK.

IT'S A BULL SHARK.

IT'S A BULL SHARK.

ALL RIGHT.

NEARLY 50 MILES FROM THE SEA,

I'VE CAUGHT A YOUNG VERSION OF THE ULTIMATE MARINE PREDATOR.

SO, THIS IS A BULL SHARK,

UPRIVER, WANDERING IN FROM THE SEA,

SPENDING PART OF ITS LIFE HERE.

THIS BULL SHARK, TAGGED BY SCIENTISTS,

HAS THE AMAZING ABILITY TO SWIM IN BOTH SALT- AND FRESHWATER.

PHYSIOLOGICALLY, IT'S COMPARABLE

TO A PERSON BREATHING ON THE MOON.

I'VE TRACKED THEM DOWN

IN RIVERS AND LAKES ACROSS THE GLOBE,

AND I'VE SEEN JUST HOW DEADLY THEY CAN BE.

BUT WITH THE RARE GLYPHIS ALSO PROWLING THESE WATERS,

THE BULL SHARK MAY NOT BE THE ONLY KILLER FISH IN THIS RIVER.

WELL, THERE'S THE PROOF

THAT THERE ARE BULL SHARKS IN THESE RIVERS,

AND I HAVE TO SAY, UNTIL I'M CONVINCED OTHERWISE,

THAT REMAINS MY NUMBER-ONE SUSPECT

FOR ANY SHARK ATTACK IN A RIVER.

TO THE UNTRAINED EYE,

THE BULL SHARK AND THE GLYPHIS ARE VERY EASY TO CONFUSE.

IT'S JUST POSSIBLE THAT THE BULL SHARK

MAY HAVE BEEN TAKING THE RAP FOR GLYPHIS ATTACKS.

I KNOW FROM EXPERIENCE

THAT THE BEST WAY TO GATHER INFORMATION

IS TO SEEK THE ADVICE OF THE LOCALS.

SO I TRAVEL FURTHER UPRIVER INTO A SERIES OF GORGES

THAT HAVE BEEN HOME TO ABORIGINAL AUSTRALIANS

FOR TENS OF THOUSANDS OF YEARS.

THEY HAVE AN INTIMATE KNOWLEDGE

OF LOCAL PLANTS AND ANIMALS.

AND ON MY LAST VISIT,

MARY AIKEN, AN EXPERT FISHERWOMAN,

WAS INSTRUMENTAL IN MY QUEST FOR THE SAWFISH.

LOCAL LEGENDS ARE FULL OF REFERENCES TO THIS MONSTER.

BUT CAN THIS ANCIENT CULTURE

TELL ME ANYTHING ABOUT THE GLYPHIS?

THERE ARE SHARKS HERE,

BUT MARY TELLS ME THEY'RE ALL BULL SHARKS.

SO, HAVE YOU CAUGHT ANY BIG ONES HERE?

YEAH. YEAH.

OUT HERE, THE TERM "BULL SHARK"

COULD MEAN ANY SHARK SWIMMING IN A RIVER.

AND GIVEN THAT GLYPHIS AND BULL SHARKS LOOK VERY SIMILAR,

I NEED TO TAKE A CLOSER LOOK

AT EXACTLY WHAT'S SWIMMING IN THESE WATERS.

STILL THERE. STILL THERE. STILL THERE. STILL THERE.

OKAY, IT'S COMING IN. IT'S COMING IN.

IT'S NOT A BULL SHARK OR A GLYPHIS.

THIS PREDATOR IS A BARRAMUNDI.

THERE YOU GO. THIS IS A BARRAMUNDI.

IT'S QUITE STRANGE FOR ME

BECAUSE THIS IS ACTUALLY JUST LIKE A NILE PERCH.

THEY DON'T GROW QUITE AS BIG AS A NILE PERCH,

BUT VERY UNCANNY, THE RESEMBLANCE.

IT'S THE SAME FAMILY.

IT'S PICKED UP A BIG DEAD MULLET OFF THE BOTTOM,

IN THE MIDDLE OF THE NIGHT.

BARRAMUNDI HAVE SANDPAPER TEETH,

WHICH MAKES THEM UNLIKELY TO INJURE PEOPLE.

YEAH, THAT WAS NOT THE ONE THAT I'M ACTUALLY AFTER.

BUT I DON'T WANT TO PUSH MY LUCK IN THIS SPOT

BECAUSE A PREDATOR EVEN DEADLIER THAN A SHARK

IS ON PATROL...

...A SALTWATER CROCODILE.

I'M CAREFUL TO SET UP CAMP

WELL BACK FROM THE WATER'S EDGE.

THE NEXT MORNING,

I GET A VISIT FROM A LOCAL GUIDE.

HE'S BEEN TOLD I'M HERE

AND HAS A STORY THAT SUGGESTS I'M NOT BEING CAREFUL ENOUGH.

DAN DUNCAN AND HIS GIRLFRIEND, SONIA,

WERE ON A FISHING TRIP IN THE OUTBACK.

AWARE OF THE DANGER FROM CROCODILES,

THEY, TOO, PITCHED THEIR TENT WELL AWAY FROM THE WATER.

BUT ON THIS NIGHT, DISTANCE WAS NO PROTECTION.

[ CROCODILE RASPING ]

THE ANSWER AFTER THIS.

I ASKED, WHAT IS THE ESTIMATED GLOBAL POPULATION

OF THE GLYPHIS GARRICKI SHARK I'M TRYING TO CATCH?

BEST ESTIMATES ARE AS FEW AS 250 ADULTS

ANYWHERE ON THE PLANET.

I'M TRYING TO TRACK DOWN THE RARE GLYPHIS SHARK

ON AUSTRALIA'S DEADLY FITZROY RIVER.

AND I'M LEARNING THE DANGERS AREN'T JUST IN THE WATER.

[ WOMAN SCREAMING ]

SOMEHOW DAN'S GIRLFRIEND

MANAGED TO AVOID THE CROCODILE'S JAWS AND ESCAPE...

Dan: GO!

...LEAVING DAN TANGLED IN THE TENT

AND FIGHTING FOR HIS LIFE.

[ SCREAMING ]

TO STAY SAFE OUT HERE,

I'M GOING TO NEED EYES IN THE BACK OF MY HEAD.

BUT THE CROC STORY HAS GOT ME THINKING

ABOUT TEETH AND BITE MARKS.

WHATEVER ATTACKED THAT MAN IN THE RIVER

MAY HAVE LEFT AN IDENTIFIABLE MARK.

TEETH MARKS ARE OFTEN THE CALLING CARD

LARGE PREDATORS LEAVE BEHIND.

I NEED TO DIG UP REPORTS ON THE ATTACK

TO LOOK FOR SOME KIND OF DENTAL SIGNATURE.

EVEN IN THE OUTBACK,

SATELLITE TECHNOLOGY PROVIDES EXACTLY WHAT I'M LOOKING FOR --

PICTURES OF THE INJURIES.

NOW, THESE ARE CLOSELY SPACED, SHARP CUTS.

DISTINCTIVE WOUNDS

THAT INSTANTLY ELIMINATE ONE POSSIBLE SUSPECT.

CROCODILES HAVE TEETH THAT ARE MUCH LARGER AND BLUNTER,

AND THEY RELY ON BITING FORCE RATHER THAN SHARP EDGES.

THEY LEAVE HEAVIER, WIDER-SPACED HOLES

THAT LOOK NOTHING LIKE THE WOUNDS IN QUESTION.

SO WHAT ABOUT THE BULL SHARK?

I'VE SEEN THEIR BITES BEFORE.

IN ONE CASE, A PRIZE RACEHORSE

WAS BEING EXERCISED IN AUSTRALIA'S BRISBANE RIVER

WHEN IT WAS ATTACKED BY A BULL SHARK.

EXPERTS INSTANTLY RECOGNIZED ITS UNIQUE SIGNATURE.

ITS TRIANGULAR UPPER TEETH LEAVE AN ARC OF CLEAN CUTS

UNLIKE ANY OTHER BITE.

ONE GLANCE AT THE MORE MESSY TEARS OF THIS NEW ATTACK

SHOWS THESE BITES ARE NOTHING LIKE THOSE OF THE BULL SHARK.

AND AS THE OBVIOUS SUSPECTS ARE ELIMINATED,

I COULD BE LOOKING AT THE FIRST KNOWN VICTIM

OF THE GLYPHIS SHARK.

I HEAD BACK DOWNSTREAM TO ANOTHER SHARK HOT SPOT,

WHERE JEFF WHITTY'S TEAM OF FISH SCIENTISTS

ARE WORKING ON THEIR SURVEY.

RECENTLY, WE'VE BEEN GOING UP TO FITZROY CROSSING,

GEIKIE GORGE, AND WE HAVEN'T DONE MUCH SAMPLING IN THIS AREA.

FOR MAXIMUM COVERAGE, THEY'RE SETTING GILL NETS

ACROSS THE WIDTH OF THE CHANNEL.

I WANT TO KEEP AN EYE ON WHAT THEY'RE CATCHING

AND ALSO TRY MY CHANCES ON A ROD AND LINE.

MY BAIT HAS BEEN STOLEN,

BUT THE SCIENTISTS ARE HAVING BETTER LUCK.

SO YOU'RE BRINGING THE NET IN? SO THERE'S NOTHING IN IT?

THEY WANT ME TO HELP FROM THE SHORE.

THERE COULD BE ANYTHING IN THERE --

A SHARK, A STINGRAY, OR SOMETHING BIGGER.

ON THE FITZROY RIVER,

I'M TRYING TO TRACK DOWN A GLYPHIS SHARK,

AND I'M HELPING TO LAND A POTENTIALLY LETHAL CATCH.

Man: WE'RE GONNA TRY AND FLIP HIM OVER.

IT'S ONE OF THE STRANGEST

AND DEADLIEST-LOOKING FISH IN THE WORLD...

THE SAWFISH.

ALL RIGHT.

WE JUST TURNED IT ON ITS BACK.

SOME FISH, YOU TURN THEM ON THEIR BACK --

IT CALMS THEM DOWN A LITTLE BIT.

THIS IS AN IMPRESSIVE-SIZE ANIMAL.

AND, I MEAN, LOOK AT THE BUSINESS END ON THAT.

IT'S NOT A GLYPHIS.

AND ALTHOUGH IT'S WELL ARMED,

THIS CAN'T BE THE ATTACKER I'M LOOKING FOR.

ALTHOUGH THE BODY LOOKS A BIT SHARKLIKE,

IF YOU GO BACK FROM THE ROSTRUM,

IT HAS GOT TEETH, BUT THEY'RE SMALL

AND THEY'RE FLAT AND THEY'RE BLUNT.

AND I CAN QUITE EASILY PUT MY HAND IN THERE --

NO DANGER AT ALL. IT'S COMPLETELY UNMARKED.

THRASHING AROUND IN A NET,

THE SAWFISH MIGHT LOOK LIKE A DEADLY WEAPON,

BUT THERE ARE NO RECORDS

OF THIS FISH DELIBERATELY ATTACKING A PERSON.

YOU REALLY SEE WHY POPULATIONS OF SAWFISH

AROUND THE WORLD HAVE PLUMMETED.

I MEAN, THESE THINGS ARE JUST SO VULNERABLE TO NETS.

IF YOU'RE A COMMERCIAL FISHERMAN, TIME IS MONEY.

YOU'RE NOT GONNA SPEND TIME DISENTANGLING IT,

THEN PUT IT BACK IN THE WATER, WHEN IT'S PROBABLY GONNA SWIM

STRAIGHT BACK INTO YOUR NET AGAIN.

YOU KNOW, A LUMP OF WOOD MAKES SENSE FOR THE FISHERMAN.

THIS IS A VERY, VERY RARE PLACE TO ACTUALLY FIND, YOU KNOW,

A SEMI-HEALTHY POPULATION OF THEM.

HE'S PUTTING A TAG IN NOW.

GONNA MAKE A HOLE, A SMALL HOLE IN THE DORSAL FIN.

AND WHAT THAT ALSO DOES,

IT PROVIDES A TISSUE SAMPLE FOR DNA ANALYSIS.

BUT THEN THE TAG GOES IN -- IT'S GOT A NUMBER ON IT.

SO IF THIS FISH IS RECAPTURED,

IT'LL TELL SOMETHING ABOUT THE MOVEMENT OF IT,

BUT ALSO GROWTH RATES.

SO A LOT OF INFORMATION COMES FROM TAGS.

THERE WE GO. I NAMED THIS FISH 1178.

FIRST THE BULL SHARK, AND NOW THE SAWFISH --

I'VE SEEN TWO OF THIS RIVER'S THREE MARINE TRESPASSERS.

THE VERY RARE GLYPHIS STILL ELUDES ME.

BUT ONE OF THE SCIENTISTS ON THIS TEAM

MAY BE ABLE TO GET ME CLOSER TO FINDING ONE.

DR. DAVE MORGAN HOLDS A UNIQUE DISTINCTION.

HE'S THE ONLY PERSON I KNOW

TO HAVE CAUGHT A GLYPHIS ON ROD AND LINE.

A NORMAL ANGLER MIGHT MISTAKE A GLYPHIS FOR A BULL SHARK.

BUT DAVE KNOWS HIS SHARKS.

Wade: ANY IDEA OF WHAT THEY MIGHT GROW TO?

THEY COULD BE POTENTIALLY DANGEROUS?

"IMPULSE STRIKE" --

IT'S THE PERFECT DESCRIPTION

OF THE ATTACK I'M INVESTIGATING.

IN THE MURKY RIVER WATER, WHATEVER BIT THE SWIMMER

COULDN'T SEE WHAT IT WAS BITING.

DAVE CAUGHT HIS GLYPHIS DOWNSTREAM,

AT THE MOUTH OF THE FITZROY, A PLACE CALLED KING SOUND.

ANY SHARK SWIMMING IN FROM THE OCEAN

MUST PASS THROUGH HERE.

AND IT MAY BE MY BEST BET

FOR CATCHING ONE OF THE RAREST SHARKS ON THE PLANET.

BUT KING SOUND HAS ITS OWN EXTREME HAZARDS.

THIS ESTUARY HAS ONE OF THE LARGEST

AND MOST DANGEROUS TIDES ON THE PLANET.

TWICE A DAY, THIS WATER, THICK WITH MUD,

CAN RISE AND FALL BY UP TO 30 FEET.

BOATS GROUND ON THE SHIFTING SANDS

OR GET WASHED OUT TO SEA BY THE VICIOUS CURRENTS.

IT'S SUICIDE TO GET IN THE WATER,

AND IT CAN BE LETHAL EVEN TO SAIL ON IT.

I'M PUTTING MY FAITH IN A STRONG HOOK,

A HEAVY WIRE TRACE, AND FRESH FISH BAIT.

IF THERE IS A GLYPHIS DOWN THERE, I'M READY FOR IT.

THERE GOES SOMETHING.

BLOODY HELL.

[ GRUNTS ]

IT'S THE WAY IT'S HANGING.

MYSTERY FISH. JUST SAW A FLASH OF GRAY.

THAT SORT OF EXPLOSION AND RAPID CHANGE OF DIRECTION --

THAT'S INTERESTING.

UP CLOSE TO THE SURFACE.

YEAH. THAT'S A WHIP RAY. THAT'S A WHIP RAY.

IT'S NOT A GLYPHIS BUT A CLOSE RELATIVE OF SHARKS.

IT'S A WHIP RAY.

BITE-WISE, NOTHING REALLY GOING ON THERE.

THEY DO HAVE TEETH.

THEY'RE NOT CUTTING TEETH.

THEY'RE JUST FLAT AND BLUNT.

WITH RAYS, IT'S NOT THE TEETH YOU HAVE TO WORRY ABOUT.

I CAUGHT A GIANT FRESHWATER STINGRAY IN THAILAND...

THE BARB ON ITS TAIL 10 INCHES LONG,

COVERED IN THICK, TOXIC MUCUS,

AND CAPABLE OF INFLICTING HORRIFIC WOUNDS.

THIS RAY IS SMALLER BUT JUST AS DEADLY.

VERY WICKED SPINE ON THE TAIL THERE,

COVERED IN THIS TOXIC VENOM.

WE DON'T WANT THAT THING IN THE BOAT.

THE THING ABOUT THE TIDE MOVING UP AND DOWN

IS THAT THE CURRENT PATTERNS CHANGE.

THE FISH ARE PROBABLY GONNA BE ON THE MOVE.

WHAT THE WATER'S DOING IS QUITE DYNAMIC,

AND WE NEED TO FOLLOW SUIT.

ALTHOUGH IT LOOKS CALM ON THE SURFACE,

THE CURRENTS ARE RUNNING UP TO 10 KNOTS.

AND WITH THE SANDS CONSTANTLY SHIFTING,

SUDDENLY THE RIVER HAS BECOME A MINEFIELD.

CAN WE GET THROUGH THIS?

IT IS VERY SHALLOW. I'M NOT SURE THAT WE WILL.

IF WE GROUND IN CURRENT THIS QUICK,

IT COULD ROLL THE BOAT.

I'M GONNA HAVE TO GET OUT OF HERE PRETTY QUICK.

IT'S REALLY SHALLOWING FAST.

IF WE TOUCH, WE'RE IN TROUBLE.

ONE MISTAKE,

AND WE'RE IN THE WATER WITH THE CROCS AND THE SHARKS.

SKIPPER ANDREW GETS US OUT OF TROUBLE,

BUT IT'S GAME OVER FOR TODAY.

THESE CONDITIONS ARE STARTING TO WORRY ME.

GETTING OUT ON THE BOAT IS NO PROBLEM,

THE FISHING IS NO PROBLEM,

WHAT'S THE PROBLEM IS GETTING BACK.

TODAY IT WAS REALLY HAIRY, AND IF IT STAYS LIKE THIS,

ACTUALLY, GOING OUT TOMORROW MIGHT NOT BE SAFE.

THE ODDS OF CATCHING THIS VERY RARE FISH

WERE ALREADY STACKED AGAINST ME.

THESE TIDES HAVE PUSHED THE ODDS OFF THE SCALE,

BUT THEY MIGHT HOLD A CLUE TO THE ATTACK I'M INVESTIGATING.

[ BIRD SQUAWKING ]

THE NEXT MORNING, DAWN'S CALM.

WE GET BACK OUT ONTO THE SOUND

AND INTO A GOOD SPOT BEFORE THE TIDE STARTS RUNNING.

THE SCIENTISTS ARE ALSO HERE, AND JEFF IS PREPARING HIS NETS.

GOOD MORNING.

HEY. HOW'S IT GOING?

YOU'RE JUST WAITING FOR THE TIDE, YEAH?

YEAH, YEAH.

IF I CATCH A SHARK,

I WANT TO BE SURE I'M IDENTIFYING IT CORRECTLY.

I DON'T WANT TO MISS A GLYPHIS.

SO, ARE YOU OPTIMISTIC FOR TODAY?

I'M ALWAYS OPTIMISTIC.

NOW, IF I GO AND PUT OUT A LINE

AND I GET SOMETHING WHICH LOOKS A BIT LIKE A BULL SHARK,

HOW WILL I KNOW IF IT IS A GLYPHIS?

A COUPLE KEY FEATURES IS THE EYE.

IT'S REALLY SMALL.

IT'S ACTUALLY SMALLER THAN A BULL SHARK.

IN ADDITION, YOU GOT THE DORSAL FINS.

UNLIKE A BULL SHARK,

THE SECOND DORSAL FIN ON A GLYPHIS IS MUCH LARGER.

SO IT'S A BIT LIKE A BULL SHARK BUT NOT QUITE.

[ Laughing ] YES. EXACTLY.

I MEAN, THE REASON THEY'RE MOSTLY CONFUSED WITH BULL SHARKS

IS BECAUSE THEY BOTH OCCUPY THE SAME HABITAT.

THAT'S REALLY MURKY, MUDDY WATERS.

SO YEAH, WE'RE GONNA HAVE TO HAVE A LITTLE LUCK ON OUR SIDE.

I LEAVE JEFF AND HIS CREW ON THE NETS.

MY CHALLENGE IS TO GET A BAIT

TO HOLD THE BOTTOM IN THE SWIRLING CURRENTS.

WHAT WE'VE DONE IS WE'VE TUCKED INTO A LITTLE EDDY

SO THAT THE MAIN PUSH IS GOING THERE,

SORT OF 15 YARDS OUT.

BUT WE'VE GOT A BACK EDDY AND SOME STILL WATER HERE,

WHICH IS EXACTLY THE KIND OF PLACE

THAT ANYTHING ON THE BOTTOM IS EXPECTING TO FIND FOOD.

ZERO VISIBILITY IN THE MUDDY WATER

MEANS I'M RELYING ON THE SHARK'S ACUTE SENSE OF SMELL

TO HOME IN ON MY FISHY BAIT.

I THINK THERE'S SOMETHING THERE.

YEAH.

I HAVE GOT A FISH.

IT'S SMALL, BUT IT MIGHT BE INTERESTING.

COULD THIS BE A GLYPHIS ON THE END OF MY LINE?

MY SEARCH FOR THE INCREDIBLY RARE GLYPHIS SHARK

HAS BROUGHT ME TO KING SOUND IN SOUND IN WESTERN AUSTRALIA.

I HAVE GOT A FISH.

IT'S SMALL, BUT IT MIGHT BE INTERESTING.

OH, IT'S A SHARK! IT'S A SHARK!

BUT HAVE I BOATED A GLYPHIS?

SPIKY TEETH ON THE LOWER JAW.

I NOW SEE FOR MYSELF

JUST HOW DIFFICULT IT IS TO IDENTIFY THESE JUVENILES.

YOU KNOW, I RECKON IT IS, YOU KNOW?

LET'S CALL JEFF.

BUT STRAIGHTAWAY, JEFF DASHES MY HOPES.

SO YOU CAN SEE HERE ALREADY, IT'S NOT A GLYPHIS.

IT'S RELATIVELY BIG-EYED

COMPARED TO WHAT A GLYPHIS WOULD BE.

OKAY. SO I WAS A BIT EXCITED, THEN.

BUT GETTING IT OUT AND THEN HAVING A GOOD LOOK AT IT,

IT'S DEFINITELY NOT.

OKAY. DO YOU KNOW WHAT IT IS?

THE TWO SUSPECTS THAT I HAVE IN MIND

ARE THE MILK SHARK AND THE CREEK WHALER.

BUT BOTH OF THESE SHARKS ARE SALTWATER SPECIES,

WHICH MEANS THIS SHOULDN'T REALLY BE HERE.

SO, IF IT'S NOT A BULL SHARK AND IT'S NOT A GLYPHIS,

THEN WHAT'S IT DOING IN THE RIVER?

THESE LARGE TIDES THAT ARE PUSHING UP,

THIS FRESHWATER BECOMES MORE SALTWATER.

SO YOU'VE GOT MARINE CREATURES

THAT ARE ON THE EDGE OF THEIR DOMAIN, PERHAPS,

AND AS THAT BOUNDARY MOVES, THEY MOVE WITH IT.

AND IF THAT MEANS GOING INLAND,

THEY COULD END UP INLAND AS WELL.

YEAH. MOST DEFINITELY.

IT'S STILL NOT MY GLYPHIS.

BUT THIS UNEXPECTED CATCH

BLOWS MY ATTACK INVESTIGATION WIDE OPEN.

IT SHOWS THAT ON WESTERN AUSTRALIA'S EXTREME TIDES,

OCEAN PREDATORS CAN FIND THEIR WAY SOME DISTANCE INLAND,

WITH A WHOLE RANGE OF NEW VICTIMS TO PREY ON.

SO, WAS THE SHARK THAT ATTACKED THE SWIMMER IN THE RIVER

NOT A GLYPHIS

BUT A SHARK YOU'D NORMALLY ONLY FIND AT SEA?

I NEED TO REVISIT THAT BITE MARK,

THE CRIMINAL'S FINGERPRINT.

SO I'VE COME TO A NEARBY ARCHIVE,

HOPING THAT A BIT OF OLD-FASHIONED RESEARCH

MIGHT REVEAL THE LAST PIECE OF THE PUZZLE.

JUST AS BULL SHARK TEETH PRODUCE A UNIQUE SIGNATURE,

SO, TOO, DO OTHER SHARKS.

AND NOW THAT I KNOW THAT OTHER SHARKS

ARE ENTERING RIVERS LIKE THE FITZROY,

I CAN PERHAPS MATCH THESE RAGGED BITE MARKS TO A CULPRIT.

THIS IS A MAKO SHARK.

AND THE TEETH HERE ARE VERY DIFFERENT.

THEY'RE NOT GONNA MAKE A CLEAN CUT.

THEY'RE JUST GONNA MAKE HOLES, MAKE A MESS.

THE MAKO HAS CARRIED OUT OVER 40 REPORTED ATTACKS

IN THE LAST 60 YEARS.

IT'S A KNOWN KILLER.

AND IT LOOKS LIKE A MAKO MADE IT UP RIVER,

BECAUSE THESE MARKS LOOK LIKE THOSE LEFT BY A MAKO'S JAWS.

THE ATTACK MYSTERY MAY BE SOLVED,

BUT MY MISSION IS FAR FROM OVER

BECAUSE I STILL HAVE TO CATCH A GLYPHIS.

AND THE ENORMITY OF THIS CHALLENGE

IS BEGINNING TO SINK IN.

JUST 20 OF THESE ANIMALS

HAVE BEEN CAUGHT HERE IN THE LAST 10 YEARS OR SO,

AND MOST OF THOSE HAVE BEEN TAKEN IN NETS.

SO WHAT I PROPOSE TO DO COULD ACTUALLY BE HARDER

THAN LOOKING FOR A NEEDLE AND A HAYSTACK.

ADD TO THAT THE FACT THAT THIS IMMENSE AREA OF WATER

HAS SOME OF THE BIGGEST, MOST DANGEROUS TIDES

ANYWHERE IN THE WORLD,

AND IT REALLY IS STARTING TO SOUND

LIKE A PRETTY CRAZY UNDERTAKING.

ATTEMPTING TO CATCH WHAT MIGHT BE THE PLANET'S RAREST SHARK

ON POSSIBLY THE WORLD'S MOST DANGEROUS RIVER...

...HAVE I FINALLY BITTEN OFF MORE THAN I CAN CHEW?

TIDE AND SANDS ARE CONSTANTLY SHIFTING

IN THE MINEFIELD OF THE ESTUARY.

BUT WE PUSH THROUGH

TO FIND SHELTER IN A POCKET OF SLACK WATER.

WITH THREE LINES OUT, NOW IT'S JUST A WAITING GAME.

I'M JUST WAITING FOR SOMETHING

MOVING AROUND IN THIS VERY DARK ENVIRONMENT TO SNIFF,

SENSE WHAT'S ON THE END OF THE LINE.

[ REEL CLICKS ] OH.

WHAT HAVE I GOT?

WHOA.

OH. IT'S A SHARK. IT'S A SHARK.

YEAH.

YEAH, IT'S...

THAT MIGHT EVEN BE A GLYPHIS.

IT'S THE RIGHT SHAPE AND THE RIGHT COLOR.

I KNOW NOW, FROM TALKING WITH JEFF,

THIS IS NOT A GLYPHIS,

BECAUSE THIS SECOND DORSAL FIN HERE IS SMALL.

ON THE GLYPHIS, THAT IS MUCH BIGGER.

THAT'S GONNA BE AT LEAST HALF THE SIZE OF THE MAIN DORSAL FIN.

THIS IS A BULL SHARK.

BUT AT FIRST GLIMPSE BREAKING THE SURFACE,

YOU JUST NEVER KNOW.

IT'S THE WRONG SHARK AGAIN.

BUT BEFORE I GET ANOTHER BAIT OUT,

THE SCIENTISTS CALL ME OVER

TO TAKE A LOOK AT THE SURPRISE THEY'VE PULLED IN.

IT'S A HAMMERHEAD SHARK.

WELL, ACTUALLY, THIS ONE IS CALLED A WINGHEAD.

I MEAN, LOOK AT THE WIDTH OF THAT HEAD.

IT'S LIKE SOME KIND OF UNDERWATER AIRCRAFT, IN A WAY.

I'VE NOT CAUGHT A HAMMERHEAD BEFORE,

SO, I MEAN, THIS IS IMPRESSIVE.

VERY STRANGE-LOOKING BEAST.

BUT I THINK WHAT THIS REALLY BRINGS HOME

IS THAT THE ESTUARY HERE IS JUST FULL OF PREDATORS.

ANOTHER MARINE HUNTER FOLLOWING IN THE SALTY TIDES.

BUT THE MORE PREDATORS THERE ARE DOWN THERE,

THE LOWER MY CHANCES OF HOOKING THE ONE I'M AFTER.

THE TIDE HAS TURNED,

AND THE FISHING IS SLOWING DOWN.

MAYBE I'M KIDDING MYSELF

TO THINK I CAN CATCH THE GLYPHIS

WHEN FEWER THAN 10 HAVE EVER BEEN RECORDED ON ROD AND LINE.

[ REEL CLICKING ]

BUT SOMETHING HAS PICKED UP MY BAIT.

IT'S MOVING.

YEAH, YEAH. THAT IS SOMETHING.

IT'S RUNNING.

[ CLICKING CONTINUES ]

IS THIS AT LAST WHAT I'VE COME TO CATCH?

[ GRUNTS ]

ON AUSTRALIA'S FITZROY RIVER,

SOMETHING IS RUNNING WITH MY BAIT.

YEAH. THAT'S SOMETHING.

VERY LIVELY.

COMING UP. COMING UP.

IT'S A SHARK, BUT IT'S FAR FROM CAUGHT,

BECAUSE IT'S FOUL-HOOKED,

WITH THE HOOK JUST NICKED IN ITS FIN.

WE CAN PROBABLY TAIL THIS.

IT COULD BREAK FREE ANY SECOND.

WE JUST HAVE TO GRAB IT.

LOOK AT THAT. LOOK AT THAT. LOOK AT THAT. LOOK AT THAT.

THAT'S OKAY. IT'S OKAY.

HOLD THERE. THAT'S GOOD.

SUDDENLY, SILENCE, BECAUSE EVERYONE ON THE BOAT

REALIZES THIS IS SOMETHING SPECIAL.

IS THIS A POSITIVE I.D. ON THIS, THEN?

YEAH, DEFINITELY. FANTASTIC.

IT'S THE FIRST TIME THIS SPECIES HAS EVER BEEN FILMED.

I'VE LANDED BIGGER RIVER MONSTERS

BUT NONE MORE RARE.

THIS IS A GLYPHIS RIVER SHARK --

VERY RARE SPECIES.

WE'VE GOT A REAL POSITIVE I.D. ON THIS --

THE SHAPE OF THE NOTCH,

JUST ALONG THE TAIL AND ALSO THE ANAL FIN.

FIRST ONE CAUGHT ON CAMERA.

IMPORTANT TO GET IT BACK NOW.

YOU CAN COUNT THE PEOPLE WHO HAVE LANDED ONE OF THESE

ON THE FINGERS OF ONE HAND.

ONE, TWO, TWO.

BUT WE NEED TO WORK FAST.

THIS SHARK IS SO RARE,

WE'RE ONLY PERMITTED TO HANDLE IT FOR 60 SECONDS.

SO, IS IT A KILLER?

IT'S A POWERFUL PREDATOR

WITH SUPER SENSES AND ALL THE RIGHT WEAPONRY.

BUT WE'VE ONLY JUST LEARNED THIS SHARK EVEN EXISTS.

AND AS YET, WE DON'T KNOW ENOUGH ABOUT ITS BEHAVIOR

OR HOW LARGE IT GROWS TO MAKE THAT CALL.

YOU ALWAYS GET THAT FEELING OF DISBELIEF

WHEN YOU PUT THE FISH BACK.

BUT I THINK WITH THIS PARTICULAR ONE,

MORE SO THAN NORMAL.

AND THE TROUBLE IS,

BECAUSE IT'S A FISH THAT THERE HAVE BEEN SO FEW CAUGHT,

WE JUST HAD TO GET IT BACK IN THE WATER QUICKLY.

THIS JOURNEY HAS SHAKEN MY ASSUMPTIONS

ABOUT WHERE THE MARINE WORLD ENDS

AND MY FRESHWATER WORLD BEGINS.

I'VE ADDED THE GLYPHIS TO THE VERY SHORT LIST

OF FISH THAT SWIM IN BOTH.

BUT CAN I ALSO ADD IT TO MY LIST

OF DANGEROUS RIVER MONSTERS?

THE JURY IS STILL OUT.

AND THIS FISH HERE,

WE DIDN'T KNOW IT WAS HERE, YOU KNOW, 10 YEARS AGO.

SO IT JUST UNDERLINES FOR ME

THE FACT THAT WHAT'S UNDER THE WATER,

YOU KNOW, IT IS STILL, EVEN IN THE 21st CENTURY,

JUST FULL OF MYSTERY.