>> male narrator: MONSTROUS CREATURES ARE TAKING OVER COASTAL WATERS WORLDWIDE. >> HUNDREDS OF MILLIONS OF THESE ARE ENTERING AT THE SAME TIME. >> AND IT WASN'T TILL I LIFT MY FOOT OUT AND I SAW WHAT IT WAS. IT WAS LIKE A BIG, WIDE CLEAR TENTACLE. >> narrator: THEY'RE SEEKING OUT THEIR PREY... >> THEN IT BECAME OBVIOUS STRAIGHTAWAY THESE ANIMALS KNEW WHERE THEY WANTED TO BE. THEY WEREN'T JUST DRIFTING AROUND. >> narrator: AND STRIKING WITH FORCE. >> THE PAIN WAS CRUSHING, AND I THOUGHT, "YOU KNOW WHAT? THEY'RE GOING TO FIND MY BODY IN THE MORNING, LYING ON THIS BEACH." >> narrator: THEIR INCREASED SIZE AND NUMBERS HAVE SCIENTISTS BAFFLED. >> YEAH, BECAUSE WE DON'T HAVE A HANDLE ON HOW THESE ANIMALS OPERATE. I MEAN, IT'S QUITE SCARY. >> narrator: NOW<i> MONSTER QUEST</i> SEARCHES THE WORLD'S OCEANS FOR ANSWERS TO THE FRIGHTENING SURGE OF ITS DEADLIEST ANIMAL: THE KILLER JELLYFISH. >> OH, WHAT THE [...] IS THAT THING? >> THREE OR FOUR OF THEM ARE AROUND US NOW. COMING IN. COMING IN. COMING IN. RIGHT BELOW YOU. >> narrator: WITNESSES AROUND THE WORLD REPORT SEEING MONSTERS. ARE THEY REAL OR IMAGINARY? SCIENCE SEARCHES FOR ANSWERS ON<i> MONSTER QUEST.</i> MOTHER NATURE HAS LONG CREATED MONSTROUS KILLERS. THE DEADLIEST OF THESE IS NOT THE BIGGEST OR THE FASTEST. IN FACT, IT'S NEARLY INVISIBLE. THIS FLOATING KILLER PREYS ON ANYTHING IN ITS PATH, AND IT IS COMING INTO CONTACT WITH HUMANS MORE AND MORE. >> THE THING WILL OUTSWIM MOST PEOPLE. IT'S GOT 24 EYES. >> AND IN A SHOCK AND A PANIC, I WENT TO FLICK THE TENTACLE OFF WITH MY HAND. >> THE VENOM THAT IT POSSESSES IS ONE OF THE MOST DEADLY VENOMS THAT WE KNOW. >> IT FELT LIKE SOMEONE WAS JUST LIKE POURING ACID OVER THE TOP OF ME. I MEAN, IT WAS SO PAINFUL. >> narrator: EYEWITNESSES REPORT SEEING GELATINOUS MONSTERS OFTEN GROWING TO THE SIZE OF A SMALL CAR AND USUALLY IN LARGE PACKS CALLED "BLOOMS." THEIR TENTACLES GROW TO TEN TIMES THE LENGTH OF THEIR BODY AND CONTAIN MILLIONS OF TINY VENOMOUS CELLS, OR "NEMATOCYSTS," THAT DISPENSE THEIR DEADLY POISON. THOSE WHO'VE ENCOUNTERED THESE FLOATING KILLERS SUGGEST THAT MASSIVE QUANTITIES OF THESE CREATURES COULD BE TAKING OVER THE SEAS. CHRIS JONES LIVES IN QUEENSLAND, AUSTRALIA, AND HAD A FRIGHTENING NOCTURNAL ENCOUNTER WHILE TRYING TO GET A GLIMPSE OF A BEACHED SPERM WHALE. >> THE WORST ENCOUNTER I'VE EVER HAD WITH BOX JELLYFISH WAS ACTUALLY SEVERAL BOX JELLYFISH. WENT OUT WITH A TORCH, A FLASHLIGHT, AND I WAS WADING THROUGH THE WATER, TRYING TO SPOT THE OUTLINE OF THIS WHALE IN THE SHALLOW WATER. >> narrator: JONES BEGAN WADING IN TO GET A CLOSER LOOK KNOWING THAT JELLYFISH MIGHT BE IN THE WATER. >> AND KNOWING THAT BOX JELLYFISH AT NIGHTTIME BASICALLY SIT ON THE BOTTOM-- THEY "SLEEP," AS SUCH, ON THE BOTTOM-- I WAS DOING THE OLD FROG WALK, WHICH IS TO TAKE VERY LARGE, LONG STEPS INTO THE WATER HOPING TO AVOID OR MINIMIZE THE CHANCES OF ENCOUNTERING ANY BOX JELLYFISH IN THE WATER. >> narrator: JONES WAS ATTACKED SEVERAL TIMES ON THE LEGS BY THE SWARMS OF DEADLY STINGERS. >> I WADED THROUGH THE TENTACLES. THEY HIT THE LOWER PARTS OF MY LEGS. IT WAS A VERY LARGE ANIMAL, AS WERE THE NEXT TWO OR THREE. I ACTUALLY LOST COUNT BECAUSE I WAS IN SO MUCH PAIN. I DON'T KNOW HOW MANY I HIT IN THE END. >> narrator: THE BOX JELLYFISH IS SO LETHAL THAT VICTIMS CAN DIE WITHIN THREE MINUTES OF CONTACT. >> I THOUGHT, "THIS IS IT. THIS IS--I'VE JUST HAD TOO MUCH VENOM. THESE ARE BIG ANIMALS. I'VE HIT MORE THAN ONCE." AND THE PAIN I WAS FEELING IN MY CHEST, I'VE NEVER FELT THAT BEFORE. IT WAS ALMOST LIKE I WAS HAVING A HEART ATTACK. >> narrator: JONES WAS RUSHED TO THE HOSPITAL BY A FRIEND WHO WAS THERE WITH HIM. >> THE PAIN WAS CRUSHING, AND I THOUGHT, "YOU KNOW WHAT? THEY'RE GOING TO FIND MY BODY IN THE MORNING, LYING ON THIS BEACH, DEAD FROM A BOX JELLYFISH." >> narrator: HE SURVIVED, BUT FEARS REMAIN THAT THIS SPECIES POPULATION IS GROWING NOT ONLY IN NUMBER BUT IN SIZE. >> AND I COULD FEEL THAT IT WAS A SERIOUS ENOUGH WEIGHT THAT IT WASN'T A SMALL ANIMAL. IT WAS QUITE A LARGE ANIMAL. >> JELLYFISH BLOOMS ARE REALLY A PROBLEM WORLDWIDE. >> narrator: PROFESSOR JOHN FINNERTY, A PROFESSOR AT THE BOSTON UNIVERSITY MARINE BIOLOGY PROGRAM, HAS STUDIED THE JELLYFISH POPULATION EXPANSION, OR BLOOM. >> A JELLYFISH "BLOOM" IS ESSENTIALLY A RAPID POPULATION INCREASE IN LARGE JELLYFISH, AND THEY CAN BECOME SO ABUNDANT AND SO DENSE THAT THEY COULD ESSENTIALLY CREATE, YOU KNOW, SLICKS ON THE WATER. IT'S ALMOST, YOU KNOW, CONTINUOUS JELLYFISH. >> narrator: JELLYFISH INHABIT EVERY OCEAN OF THE WORLD, AND THE PROBLEM IS EXPLODING AS SWARMS OF THESE MONSTERS ARE GETTING CLOSER AND CLOSER. IN SPAIN, AN INVASION OF 60 MILLION JELLYFISH SWEPT UP ON A SPANISH BEACHES AND STUNG MORE THAN 70,000 PEOPLE. OFF NORTHERN IRELAND, A 10-MILE-WIDE AND 42-FOOT-THICK SWARM OF THESE MONSTERS WIPED OUT THE SALMON POPULATION, KILLING SOME 120,000 FISH. AND IN THE SUMMER OF 2008, THE UNITED STATES' EASTERN SEABOARD SAW MASSES OF JELLYFISH ATTACKING SWIMMERS AND WADING CHILDREN. FINNERTY BELIEVES THAT MANKIND MAY BE FEEDING THE GROWTH OF THESE MONSTERS. >> THERE ARE SOME THINGS WE'RE DOING. THE HUMANS ARE IMPACTING THE OCEAN, AND IT COULD BE INCREASING THE FREQUENCY OF THESE REALLY DEVASTATING JELLYFISH BLOOMS. ONE THING THAT WE'RE DOING, FOR EXAMPLE, IS, WE'RE CREATING DEAD ZONES IN THE OCEAN. THESE ARE AREAS WHERE BECAUSE OF POLLUTION, ESPECIALLY FERTILIZER RUNOFF, WE ENCOURAGE THE GROWTH OF LOTS OF PLANKTON IN THESE AREAS OF THE OCEAN. THOSE PLANKTON CONSUME LOTS OF OXYGEN, AND BECAUSE OF THAT, THERE'S NOT MUCH OXYGEN IN THE WATER. >> narrator: THIS LACK OF OXYGEN IN THE WATER MAKES THE OCEAN A PERFECT SPAWNING GROUND FOR JELLYFISH. THIS IS BECAUSE THE OXYGEN DEPLETION WOULD WIPE OUT MANY OTHER SPECIES WHILE THE RESILIENT JELLYFISH WOULD FLOURISH DUE TO THE LACK OF COMPETITION FOR FOOD SOURCES. >> THE OTHER SEA LIFE DO NOT DO AS WELL. JELLYFISHES ARE ACTUALLY FAIRLY--THEY APPEAR TO BE VERY HARDY AND RESILIENT IN THE FACE OF SOME OF THE THINGS WE'RE DOING TO THE OCEANS SO THEY BECOME VERY ABUNDANT IN THESE AREAS. >> narrator: FINNERTY ISN'T ALONE IN HIS VIEWS. >> [speaking Japanese] >> THERE IS A THEORY OF SUCH THAT GLOBAL WARMING HAS CAUSED A RISE IN TEMPERATURES AND SEAWATER AND THAT HAS CONTRIBUTED TO THEIR GROWTH. >> narrator: SCIENTIFIC ESTIMATES SAY THE WORLD'S JELLYFISH POPULATION IS GROWING AT AN ALARMING RATE. HISTORICALLY, MASSIVE BLOOMS OF NOMURA JELLYFISH HAVE BEEN REPORTED ONLY ABOUT ONCE EVERY 40 YEARS: IN 1920, 1958, AND 1995. BUT SINCE 2002, THE NOMURAS HAVE INVADED JAPAN'S WATERS FIVE TIMES. THIS INCREASE COULD HAVE TERRIFYING IMPLICATIONS DUE TO THEIR VENOMOUS MAKEUP. THERE ARE SOME EXPERTS, HOWEVER, WHO REMAIN SKEPTICAL. MIKE KINGSFORD, A BIOLOGIST FROM JAMESTOWN UNIVERSITY, AUSTRALIA, BELIEVES MORE STUDY IS NEEDED. >> WELL, IT'S ACTUALLY QUITE INTERESTING. GIVEN THE HYPE ON JELLYFISH, THERE'S ACTUALLY VERY LITTLE KNOWN ABOUT WHERE THEY ARE. I THINK THERE'S A PARANOIA OUT THERE THAT EVERY TIME YOU GET STUNG, YOU'RE GOING TO DIE. THAT'S NOT THE CASE. IF YOU INCLUDE BOTH THE STINGERS AND IRUKANDJI JELLYFISH, PROBABLY LESS THAN .5% OF PEOPLE ACTUALLY GET KILLED BY THEM. >> narrator: JELLYFISH ENCOUNTERS APPEAR MOST PREVALENT IN THE PACIFIC OCEAN, AND IT IS HERE THAT <i> MONSTER QUEST</i> WILL LAUNCH ITS EXPEDITION. THE TEAM WILL SEARCH IN JAPAN, WHERE A RECENT INFLUX OF JELLYFISH HAS HAD A DEVASTATING EFFECT; AND OFF THE COAST OF AUSTRALIA, HOME TO THE DEADLY BOX JELLYFISH, THE MOST FEARED PREDATOR OF THE SEA. >> THERE'S A THEORY GOING AROUND THAT JELLYFISH ARE GETTING BIGGER ALL OVER THE WORLD, AND THIS IS THE PLACE WHERE THE JELLYFISH ARE THE MOST LETHAL, AND THAT'S WHAT OUR GOAL IS: TO GO OUT THERE AND SEE IF WE CAN DOCUMENT THAT PHENOMENON. >> narrator: THE PACIFIC IS HOME TO THOUSANDS OF DIFFERENT TYPES OF JELLYFISH, INCLUDING THE DEADLY BOX JELLY AND IRUKANDJI. THESE WATERS ARE ALSO HOME TO A VARIETY OF DEADLY PREDATORS, INCLUDING STINGRAYS AND BULL SHARKS, MAKING THIS ONE OF THE RISKIEST EXPEDITIONS TO DATE. LEADING THE EXPEDITION IS DIVER DALE PEARSON. >> WE'RE GOING TO TRY TO DOCUMENT THE BIGGEST ONE WE CAN FIND. >> narrator: THE TEAM WILL ALSO ATTEMPT TO FIND EVIDENCE OF LARGER THAN NORMAL POPULATIONS WITH A FOCUS ON THE DANGEROUS BOX JELLYFISH. PEARSON HAS DESIGNED EXTRA PRECAUTIONS TO MINIMIZE THE CHANCE OF A POTENTIALLY LETHAL STING. >> WE'RE GOING TO GO THROUGH SOME PRETTY SERIOUS PROTOCOL. WHEN WE GET OUT OF THE WATER, WE'RE GOING TO HAVE A VINEGAR WASH. WE'RE GOING TO WASH OURSELVES DOWN WITH THE VINEGAR, ALLOW 30 SECONDS TO DEACTIVATE ANY CHEMICAL OR ANY OF THE TENTACLES THAT MIGHT BE STUCK TO OUR WETSUIT. THIS IS THE GEAR WE BROUGHT. WE'VE GOT UNDERWATER COMMUNICATION SYSTEMS, FULL FACEMASKS, AND WHAT THAT'S GOING TO DO IS, THAT'S GOING TO PROTECT OUR FACE SO WE DON'T HAVE ANY SKIN EXPOSED RIGHT UP HERE AROUND THE MOUTH IN CASE WE GET A SHOT TO THE FACE. UNDERWATER VIDEOGRAPHY EQUIPMENT TO DOCUMENT WHATEVER WE FIND. OBVIOUSLY FULL WETSUITS, GLOVES, BOOTIES, EVERYTHING. COMPLETELY COVER UP ALL YOUR SKIN. >> narrator: JELLYFISH CAN BE ESPECIALLY DIFFICULT TO DEAL WITH BECAUSE THEIR TENTACLES CAN OFTEN BE VERY HARD TO SEE. >> FIGURE IF IT'S GOT TENTACLES A COUPLE METERS OFF OF IT THAT ARE INVISIBLE, YOU DON'T KNOW WHICH WAY THE TENTACLES ARE GOING, THERE'S A CERTAIN AMOUNT OF RISK THAT'S INVOLVED TO GETTING THAT CLOSE TO GET THE SHOTS. IF SOMETHING HAPPENS AND I CATCH ENOUGH TENTACLE FROM ONE OF THOSE THINGS, THAT I'LL BE DEAD BEFORE I GET IN THE BOAT. >> narrator: THE BOX SPECIES ARE KNOWN TO REST ON THE OCEAN FLOOR AT NIGHT. AS A RESULT, THE TEAM WILL BEGIN BY SEARCHING DURING NIGHTTIME HOURS. >> LET'S GO, LET'S GO, LET'S GO, LET'S GO. >> PAUL AND I ARE GOING TO GO DIVE IN AND HIT THE BOTTOM AND BASICALLY COMB THE BOTTOM AND SEE IF WE CAN FIND ANYTHING DORMANT ON THE BOTTOM AT NIGHT. >> narrator: WHILE THE DARKNESS PROVIDED BY A NIGHT DIVE INCREASES THE CHANCES OF QUICKLY SPOTTING THE JELLYFISH'S BIOLUMINESCENT BODY, IT ALSO INCREASES THE RISKS INVOLVED. >> THE DIFFERENCE BETWEEN DIVING AT NIGHT AND DIVING IN THE DAY IS OBVIOUSLY EXTREMELY LIMITED VISIBILITY. YOU CAN'T SEE ANYTHING EXCEPT FOR WHAT'S ILLUMINATED BY YOUR LIGHTS. THE THING THAT CONCERNS ME HERE IS THE BULL SHARKS. BULL SHARKS GOT THE HIGHEST TESTOSTERONE OF ANY SHARK IN THE OCEAN, AND THERE'S SOME BIG ONES HERE. I DON'T HAVE ANY DIVE ARMOR WITH ME. SO HOPEFULLY THE EXTRA RISK THAT'S INVOLVED GOING NIGHT DIVING WILL BE FRUITFUL. WE'LL FIND WHAT WE'RE LOOKING FOR THIS WAY. >> narrator: THE TEAM BEGINS ITS SEARCH NEAR THE GREAT BARRIER REEF, 15 MILES OFF THE COAST OF CAIRNS, AUSTRALIA. >> READY TO ROLL. >> narrator: THE DIVERS ENTER THE WATER, KEEPING A KEEN EYE OUT FOR ANY PREDATORS THAT MAY BE NEARBY. >> TOPSIDE, COMM CHECK. JUST CHECKING TO SEE IF YOU GUYS CAN HEAR ME OKAY. >> CAPTAIN, I COPY. BE ADVISED, YOU ARE COMING IN VERY WEAK. OVER. WE CANNOT COPY YOU DOWN HERE. OVER. >> narrator: THE PROBLEMS WITH THE COMMUNICATION SYSTEM MEANS THAT HELP FROM THE SURFACE WILL BE LIMITED. >> TOPSIDE, COPY. CAN YOU GUYS HEAR ME ANY BETTER NOW? >> WE DO NOT READ YOU. YOU ARE VERY SCRAMBLED. OVER. >> narrator: THE DIVERS WILL NEED TO BE MORE ALERT TO COMMUNICATE WITH EACH OTHER IN ORDER TO COMPENSATE. >> THERE'S SOME LITTLE JELLYFISH RIGHT THERE. LOOK AT THAT THING. >> narrator: AS THE DIVERS MAKE THEIR WAY THROUGH THE WATER, SUDDENLY SOMETHING APPEARS OUT OF THE BLACKNESS. >> OH, WHAT THE [...] IS THAT THING? LOOK AT THAT. LOOK AT THAT WHITE THING. LOOK. >> narrator: THE FISH SCATTER. SUDDENLY THERE'S ANOTHER. THE DIVERS FIND THEMSELVES IN THE MIDDLE OF A SHARK FEEDING FRENZY. >> OH, WE GOT EVERYTHING: TUVALU SHARKS, BARRACUDA. WE GOT THREE OR FOUR OR 'EM AROUND US NOW. COMING IN. COMING IN. COMING IN. RIGHT BELOW YOU. >> THAT SHARK COULD'VE HIT ME. JELLYFISH ARE ONE OF THE OLDEST SPECIES ON THE PLANET, HAVING INHABITED THE EARTH'S OCEANS FOR MILLIONS OF YEARS. A RECENT FOSSIL DISCOVERY IN UTAH DATES THE SPECIES AT OVER 500 MILLION YEARS OLD. AMAZINGLY, VERY LITTLE EVOLUTIONARY CHANGE HAS OCCURRED IN THAT TIME. THE MERE EXISTENCE OF THIS CREATURE HAS HAUNTED SAILORS THROUGHOUT HISTORY. THE SHIP<i> KURANDA</i> WAS AT HIGH SEAS NEAR THE FIJI ISLANDS. THE SHIP WAS FIGHTING TO STAY SEAWORTHY WHEN A GIANT WAVE CRASHED ACROSS ITS DECK AND A MASSIVE JELLYFISH APPEARED. THE CREW ESTIMATED THE CREATURE TO BE IN EXCESS OF 20 TONS. THE SHIP'S CAPTAIN QUICKLY SENT OUT AN S.O.S. CALL BEGGING FOR HELP AND FREEING THE SHIP OF THE BEAST. BEFORE HELP ARRIVED, A CREWMAN WAS HIT BY THE TENTACLES, AND HIS SKIN WAS SEVERELY BURNED. ANOTHER VESSEL FINALLY ARRIVED AND USED A HIGH-POWERED HOSE TO FREE THE KURANDA FROM THE GRASP OF A HUGE JELLYFISH. UNFORTUNATELY, IT WAS TOO LATE FOR THE INJURED SAILOR, WHO DIED FROM HIS WOUNDS. THE EARLY ABORIGINAL PEOPLE OF AUSTRALIA HAVE LONG KNOWN ABOUT THE DEADLY BOX JELLYFISH. AND DEPICTIONS OF THIS FEARED AND MYSTERIOUS CREATURE CONTINUE TO THIS DAY. IT WAS NOT UNTIL AFTER THE DEATH OF A FIVE-YEAR-OLD BOY AT CARDWELL, AUSTRALIA, IN 1955 THAT<i> CHIRONEX FLECKERI,</i> OR THE BOX JELLYFISH, WAS OFFICIALLY NAMED. TODAY, SCIENTISTS REMAIN CURIOUS ABOUT THE JELLYFISH, AND THERE IS LESS KNOWN ABOUT THE DANGEROUS BOX SPECIES THAN ANY OTHER. >> BOX JELLYFISH ARE SQUARE, HENCE THE NAME "BOX JELLYFISH." THEY CAN BE QUITE LARGE. >> narrator: DR. JAMIE SEYMOUR IS DIRECTOR OF THE STINGER RESEARCH UNIT AT JAMES COOK UNIVERSITY IN CAIRNS. HE IS THE WORLD'S LEADING RESEARCHER ON BOX JELLYFISH. >> I'M NOW TALKING ABOUT ARGUABLY THE WORLD'S MOST VENOMOUS ANIMAL, SOMETHING THAT COULD STING YOU AND KILL YOU WITHIN 120, 180 SECONDS OF BEING STUNG, AND WE KNOW DIDDLEY SQUAT ABOUT IT. IT'S QUITE SCARY. I MEAN, WE DON'T KNOW, FOR EXAMPLE, WHERE THE ANIMALS BREED. TO BE HONEST, WE DON'T KNOW HOW THEY BREED. WE DON'T KNOW HOW LONG THEY LIVE FOR. WE DON'T KNOW HOW MANY OFFSPRING THEY PRODUCE. >> narrator: THIS DEADLY CREATURE IS AN APEX PREDATOR AND IS KNOWN TO HUNT AND FEED ON SHRIMP AND SMALL FISH. THEY DO THIS EXTREMELY EFFICIENTLY USING THEIR LONG AND POWERFUL TENTACLES. >> IF YOU THINK A JELLYFISH AS BEING SORT OF YOUR STANDARD, RUN-OF-THE-MILL FOUR-CYLINDER CAR, BOX JELLYFISH ARE THE FORMULA ONE OF THE WORLD. I MEAN, THEY HAVE A V8 ENGINE. THESE THINGS SWIM AT 2.5 OR 3 KNOTS. I MEAN, THAT'S ABOUT THE SPEED OF MOST PEOPLE CAN NORMALLY SWIM. THEY'VE GOT THE MOST POTENT VENOM THAT WE KNOW OF. THERE IS NO OTHER ANIMAL IN THE WORLD THAT CAN KILL YOU AS QUICKLY AS A BOX JELLYFISH. >> narrator: SEYMOUR'S RESEARCH INTO THE DEADLY VENOM HAS LED TO A NEW UNDERSTANDING OF HOW THESE CREATURES KILL SO EFFECTIVELY. >> THE VENOM FROM THESE THINGS IS BY IN LARGE A CARDIAC VENOM, SO IT ATTACKS THE HEART. YOU GET STUNG, IT'S DROPPED DIRECTLY INTO THE CIRCULATORY SYSTEM, OR THE VEINS AND THE ARTERIES, GOES STRAIGHT INTO YOUR HEART, AND THE VENOM IS VERY, VERY SPECIFIC. BY AND LARGE, IF YOU HAVE MORE THAN THREE OR FOUR METERS' WORTH OF TENTACLE ON YOUR BODY, YOU'RE PRETTY MUCH DEAD BEFORE WE GET YOU OUT OF THE WATER. SO--AND THERE'S NOT ENOUGH-- NOT A GREAT DEAL YOU CAN DO ABOUT IT. >> narrator: IF EXPERTS LIKE SEYMOUR BELIEVE JELLYFISH POPULATIONS ARE EXPANDING, THE EFFECT COULD BE DEVASTATING. >> I'VE SEEN THEM OPERATE IN THE FIELD IN A GROUP OF TWO, CORRAL UP A SCHOOL OF FISH, AND ONE JUST SWIMS THROUGH, GRABS A FISH AND SWIMS AWAY. NOW, THIS IS NOT AN ANIMAL THAT'S JUST WIDELY BLUNDERING INTO THINGS. >> narrator: THIS MEANS THAT IF WHAT SEYMOUR IS SUGGESTING IS TRUE, JELLYFISH ARE TARGETING THEIR PREY. >> NOW, MOST PEOPLE WILL ARGUE THIS. I MEAN, I'VE BEEN TO CONFERENCES WHERE I'VE SUGGESTED THIS AND HAD, YOU KNOW, MY PEERS GO, "NO, YOU'RE OUT OF YOUR TREE. THESE ANIMALS ARE 96% WATER. NO BRAINS. THEY CAN'T DO THIS." >> SEYMOUR WILL LEAD THE<i> MONSTER QUEST</i> SCIENCE TEAM IN CONDUCTING AN ANALYSIS OF VIDEO FOOTAGE THAT COULD CLEARLY SHOW A BOX JELLYFISH NAVIGATING AND HUNTING ITS NEXT VICTIM. >> BECAUSE IT'S HUNTING FISH. I MEAN, THEN THAT MEANS IT CAN GET INTO THIS COMPLEX ENVIRONMENT; IT CAN CHASE FISH WHERE OTHER JELLYFISH CAN'T GET. AND THAT'S ONE OF THE ADVANTAGES OF HAVING ALL THIS, BUT THERE IS NO WAY YOU CAN DO THIS UNLESS YOU CAN SEE WHAT'S GOING ON. AND THAT'S WHAT SETS THESE THINGS APART FROM ALL THE OTHER JELLYFISH. >> narrator: BOX JELLYFISH ARE EQUIPPED WITH 24 EYES, WHICH GIVES THEM A 360 DEGREE VIEW OF THEIR SURROUNDINGS. >> CERTAINLY I'VE HAD 'EM IN A TANK HERE WHERE THEY'LL SWIM UP TO MEET YOU. I MEAN, THE ANIMALS, YOU KNOW, HAVE SOME SORT VISUAL STRUCTURE THERE. THEY DON'T HAVE A BRAIN AS SUCH, SO WE DON'T KNOW HOW THEY HECK THEY PROCESS THESE IMAGES. >> THE POSSIBILITY THAT THESE CREATURES POSSESS SOME FORM OF INTELLIGENCE POSES AN EVEN GREATER THREAT TO MANKIND. THE<i> MONSTER QUEST</i> EXPEDITION TEAM IS BENEATH THE SURFACE OF THE WATER, THE AREAS PREDATORS ARE FEEDING, AND IT MAKES THE CONDITIONS EVEN MORE DANGEROUS. >> WE'VE GOT EVERYTHING: TUVALU SHARKS, BARRACUDA. >> WE GOT THREE OR FOUR OF THEM AROUND US NOW. THAT SHARK COULD'VE JUST HIT ME. >> narrator: THE MEN ARE SURROUNDED BY GREY REEF SHARKS AND HAVE NO COMMUNICATION WITH THE BOAT. IF THEY ARE ATTACKED, THEY WILL HAVE NO BACKUP. THEY MUST GET OUT OF THE AREA. >> YOU'RE RIGHT UNDER THE BOAT, RIGHT DIRECTLY UNDERNEATH THE BOAT, SO YOU'RE GOOD. >> narrator: LUCKILY, THEY FIND THE BOAT AND MANAGE TO ESCAPE THE SHARKS. >> WE SAW ONE LITTLE SHARK OFF OF THE OUTSIDE. WE'RE LIKE, "OH, HEY. THERE'S A LITTLE SHARK." AND ALL OF A SUDDEN, BOOM, I SAW ONE GO. YOU'RE FILMING ONE, ALL OF A SUDDEN, BOOM, THERE'S ANOTHER ONE BEHIND YOU. BOOM, THERE'S ANOTHER ONE BEHIND IT. I'M LIKE, "ALL RIGHT, WE GOT THREE. WE GOT FOUR NOW." AND THE NEXT THING YOU KNOW, IT JUST GOT CRAZY, MAN. I SEEN 'EM COME RIGHT UP UNDERNEATH YOU. I WAS LOOKING AT YOU FROM ABOVE. I WAS LIKE, "GOD, I WONDER IF HE SEES THAT THING. THAT'S PRETTY CLOSE TO HIM." AND ALL OF A SUDDEN IT JUST CAME LIKE RIGHT UNDERNEATH YOUR ARM, RIGHT UNDER THE CAMERA." >> narrator: THE TEAM IS NOT COMPLETELY OUT OF DANGER. THERE ARE REPORTS OF A VIOLENT CYCLONE BREWING TO THE NORTH AND IT IS CARRYING 70 MILE AN HOUR WINDS AND TORRENTIAL RAINS. >> AND IT WAS JUST GETTING GNARLIER AND JUST HEAVIER AND HEAVIER. THE JELLYFISH POPULATION IN JAPAN IS 100 TIMES GREATER THAN 20 YEARS AGO. MANY EXPERTS SAY GLOBAL WARMING MAY BE CAUSING THIS. IN 2006, NOMURA JELLYFISH BLOCKED THE SEAWATER COOLING SYSTEM AT A NUCLEAR POWER PLANT IN HAMAOKA, JAPAN. AUTHORITIES HAD TO SHUT DOWN THE PLANT IN ORDER TO AVOID DISASTER. THE INVASION KILLED MILLIONS OF FISH. THE JELLYFISH ALSO ATTACKED FISHERMEN. >> [speaking Japanese] >> THE SCARIEST THING IS THE TENTACLES. WE ARE ALL SCARED OF THE JELLYFISH. BECAUSE THEIR STING IS SO ITCHY, WE FISHERMEN CANNOT KEEP WORKING. >> narrator: THE NOMURA JELLYFISH IS ONE OF THE LARGEST IN THE OCEAN, MEASURING MORE THAN SIX FEET WIDE AND WEIGHING IN AT OVER 450 POUNDS. THIS ASTONISHING VIDEO IS EVIDENCE OF THE MONSTER JELLYFISH BLOOM THAT CLOGGED THE SEA OF JAPAN. THE MAN WHO SHOT THE VIDEO IS TRYING TO UNDERSTAND WHY. >> IT WAS NEVER STUDIED BEFORE, SO WE KNOW NOTHING ABOUT THEM AND HAVE TO START LEARNING ABOUT THEM FROM SCRATCH. >> narrator: NAOTA HONDA IS A RESEARCHER FOR THE FISHERIES RESEARCH AGENCY IN TOKYO. HE HAS BEEN STUDYING THESE CREATURES FOR SIX YEARS. >> UNTIL RECENTLY, WE HARDLY SAW THEM. BUT FIVE YEARS AGO, THEY STARTED TO APPEAR IN LARGE NUMBERS. >> narrator: THERE ARE SEVERAL THEORIES AS TO WHY THE NOMURA TOOK OVER THE SEA OF JAPAN. >> THEY ARE MANY THEORIES WHY THIS PARTICULAR JELLYFISH INCREASED IN RECENT YEARS. FOR INSTANCE, ONE OF THEM IS JELLYFISH STARTED TO INCREASE NEAR THE CHINESE COASTLINE BECAUSE OF THE POLLUTION IN THE WATERS. >> narrator: HONDA BELIEVES THERE MAY BE ANOTHER EXPLANATION. >> ANOTHER THEORY IS THAT GLOBAL WARMING HAS CAUSED JELLYFISH TO GROW MORE EASILY. >> narrator: THE JAPANESE GOVERNMENT HAS ASKED HONDA TO LOCATE AND TRACK THESE ANIMALS TO FIGURE OUT WHY THEY KEEP INVADING THE SEA OF JAPAN. HE'S TARGETED SAGAMI BAY, AN HOUR'S DRIVE FROM TOKYO. HONDA WILL USE SONAR AND UNDERWATER CAMERAS TO LOCATE THE NOMURA. ONCE HE FINDS THEM, HE WILL USE A TRACKING DEVICE HE DESIGNED TO FOLLOW THE ANIMAL'S MOVEMENTS. THE DEVICE FITS LIKE A BELT AROUND THE NOMURA AND TRANSMITS A SIGNAL TO A SATELLITE WHICH THEN RELAYS INFORMATION ABOUT THE NOMURA'S PATTERNS BACK TO HIS OFFICE. THE CREATURE IS NOT HURT, AND THIS ONE-OF-A-KIND TRACKING SYSTEM MAY PROVIDE VITAL INFORMATION AS TO WHY THESE CREATURES INVADE WHEN THEY DO. THE NOMURA IS NOT LETHAL, BUT ITS STING IS STILL EXTREMELY PAINFUL. >> I WAS SCARED OF GETTING TOO CLOSE TO THE JELLYFISH BECAUSE THEY WERE BIGGER THAN PEOPLE. >> narrator: HONDA WAS ATTEMPTING TO ATTACH HIS TRACKING SYSTEM ON A NOMURA DURING A RESEARCH TRIP. >> I WAS WORKING ON TAGGING THE JELLYFISH. I GOT TOO CLOSE AND THE TENTACLES TOUCHED MY FACE AND I FELT PAIN. AT THE TIME, I WANTED TO COMPLETE THE JOB I WAS DOING SO I ENDURED THE PAIN. >> narrator: HONDA NOW WEARS A FULL FACEMASK WHEN HANDLING NOMURA. HE AND HIS TEAM ARRIVE AT THEIR FIRST DIVE LOCATION. >> THE MAXIMUM BOTTOM IS 14 METER, AND WATER TEMPERATURE SHOULD BE 16 DEGREES. I'M GOING TO TAKE CARE OF THE HONDA-SAN. >> narrator: HONDA ENTERS THE ICY WATERS. >> HEY, HONDA-SAN, HOW ARE YOU DOING IN THE BOTTOM? ARE YOU OKAY NOW? >> HOW ABOUT THE JELLYFISH? ARE THERE JELLYFISH OUT THERE? >> WOW. >> narrator: BUT HONDA HAS SPOTTED A STARFISH ON THE BOTTOM OF THE OCEAN. >> THERE NORMALLY ARE NO STARFISH OUT THERE. THERE BE A STARFISH UP THERE. IT'S UNUSUAL, I THINK. >> narrator: HONDA BELIEVED THE STARFISH IS A SIGNIFICANT DISCOVERY. THEY'RE USUALLY ONLY FOUND IN TROPICAL CLIMATES. THIS BAY IS NOT CONSIDERED TROPICAL AND THE TEAM IS DIVING IN THE MIDDLE OF WINTER. THE PRESENCE OF A STARFISH INDICATES A SIGNIFICANT RISE IN WATER TEMPERATURES AND SUPPORTS HONDA'S THEORY THAT GLOBAL WARMING IS RESPONSIBLE FOR THE INCREASE IN THE NOMURA JELLYFISH POPULATION. >> ALL RIGHT, SO, HONDA-SAN, HOW WAS POSITION DIVING? THE POSITION OF DIVING? >> VERY GOOD. >> SHALL WE GO LOOKING FOR NOMURA JELLYFISH? MAYBE UP THERE? AROUND THERE? >> YES. >> narrator: THE TEAM HEADS TO DEEPER WATER. IT'S A RISKIER DIVE BECAUSE OF THE DANGER OF STRONGER CURRENTS WASHING THE DIVER OUT TO SEA. HONDA BELIEVES TAKING THE RISK IS WORTH IT. >> THE HONDA-SAN IS READY TO DIVE NOW. >> narrator: HONDA FINDS HE IS IN A STRONG DOWN CURRENT. THIS IS AN AREA OF THE SEA WHERE THE SEAFLOOR DROPS OFF AND STRONG CURRENTS PUSH OUT TOWARDS OPEN WATER. THIS MAKES IT DIFFICULT TO STAY AT THE APPROPRIATE DEPTH. IT CAN PROVE DEADLY EVEN FOR AN EXPERIENCED DIVER. >> HONDA-SAN, DO YOU HAVE ANY CURRENT? >> OH, OKAY. AH, THE BOAT FOLLOW YOU. >> narrator: HONDA CONTINUES TO FIGHT THE STRONG CURRENT. >> HONDA-SAN, CAN YOU HEAR ME? >> narrator: THE CURRENT IS TAKING ITS TOLL ON HONDA PHYSICALLY. >> CAN YOU SEE A NORMAL JELLYFISH? >> NOTHING. >> OKAY. >> narrator: HE'S CONVINCED THE NOMURAS ARE GROWING IN NUMBER, BUT THE CONDITIONS ARE TOO BRUTAL. IT BECOMES TOO DANGEROUS TO CONTINUE. HONDA CALLS OFF THE REST OF THE EXPEDITION. >> CHECK, CHECK. ONE, TWO. OBVIOUSLY, THE JELLYFISH THAT CAN KILL YOU ON CONTACT IS THE ONE THAT'S STICKING IN MY MIND. >> narrator: AUSTRALIA'S TROPICAL CYCLONE CHARLOTTE HAS FORCED THE SOUTHERN PART OF THE<i> MONSTER QUEST</i> EXPEDITION TEAM TO MOVE FURTHER SOUTH. THE DIVERS ARE RACING TO GET INTO THE WATER BEFORE THE RAINS FORCE THEM TO ABORT THEIR MISSION. >> WHAT THE CAPTAIN'S DONE IS, HE'S MOVED US OFF TOWARD THE EDGE OF THE REEF FOR THE WATERS A LITTLE BIT DEEPER. A LITTLE BIT MORE CURRENT HERE. WE'RE NOT GOING TO BE ABLE TO ACTUALLY GET IN THE WATER AND STAY HERE BY THE BOAT BECAUSE OF THE CURRENT, SO WE'RE GOING TO DO WHAT THEY CALL A DRIFT DIVE. WHERE WE'RE JUST GOING TO GET IN THE WATER AND LET THE CURRENT TAKE US WHERE IT TAKES US. >> narrator: THIS WILL ALLOW THEM TO COVER MORE AREA. >> KIND OF RUNNING THAT WAY, SO THEY WON'T HAVE TO WORRY ABOUT IT TOO MUCH. THEY'LL JUST DRIFT WITH IT AND WE'LL JUST MOVE SLOWLY DOWN THE REEF WITH THEM, AND THEN WHEN THEY SURFACE, WE'LL GET THEM TO COME JUST AWAY FROM THE REEF A LITTLE. WE'LL GO IN BETWEEN THEM AND THE REEF AND THEY'LL PICK THEM UP IN DEEP WATER. >> narrator: THEY'RE HOPEFUL THE STORMY CONDITIONS ABOVE THE WATER WILL NOT EFFECT THE VISIBILITY BELOW THE SURFACE. >> narrator: TEAM LEADER DALE PEARSON DRIFTS ALONG THE REEF, KEEPING A WATCHFUL EYE FOR JELLYFISH AND OTHER PREDATORS OF THE DEEP. THE REEF IS ALIVE WITH MARINE ANIMALS. >> YEP. >> narrator: THE BOAT'S CAPTAIN SPOTS A JELLYFISH FLOATING IN THE WATER. HE DIVES IN TO CAPTURE IT. >> YOU HAVE THE LONG TRAWLING TENTACLES AS WELL AS THE BUNTING TENTACLES. BOTH OF THEM CAN STING. AND ON THE TOP OF THE BELL YOU'LL SEE THERE'S SOME ROUGHER TEXTURE ON THE SURFACE THERE. SOME OF THE TEXTURE ON THE SURFACE THERE HAS GOT STINGING CELLS AS WELL. >> narrator: THEY QUICKLY DETERMINE ITS NOT THE LETHAL BOX JELLYFISH. >> UH, THIS ONE WILL PROBABLY GIVE YOU A STING HERE SO YOU'LL YOU KNOW ABOUT IT, BUT NOT LIFE-THREATENING. NOT LIKELY LIFE-THREATENING AT ALL. >> narrator: PEARSON AND THE TEAM CONTINUE TO DRIFT ALONG WITH THE CURRENT, NEARLY THREE MILES FROM WHERE THEY BEGAN, SCANNING THE WATERS FOR SIGNS OF A NEARLY INVISIBLE KILLER. THIS CREATURE'S STING CAN KILL IN JUST THREE MINUTES. THOSE FORTUNATE ENOUGH TO SURVIVE AN ATTACK EXPERIENCE EXCRUCIATING PAIN. >> THE PAIN WAS LIKE IF I HELD A CIGAR ON YOUR FOOT FOR TWO HOURS. >> narrator: MICHAEL ANDERSON HAD JUST FINISHED A DAY ON THE WATER WHEN HE WENT TO RETRIEVE HIS BOAT. >> WHEN I BACKED THE TRAILER BACK DOWN, I WALKED-- AS I WAS WALKING INTO THE-- DOWN THE BOAT RAMP INTO THE SEA TO GET THE BOAT, A WAVE WASHED UP OVER MY FOOT AND IT FELT LIKE A FISHING LINE GOT WRAPPED AROUND MY FOOT. AND IT WASN'T UNTIL I LIFT MY FOOT OUT AND I SAW WHAT IT WAS. AND IT WAS LIKE A BIG, WIDE CLEAR TENTACLE, AND IT LOOKED LIKE IT WAS SORT OF MELDING INTO ME FOOT. >> narrator: THE PAIN IN HIS FOOT WAS AN INSTANT BURN. ANDERSON QUICKLY WIPED THE TENTACLE OFF HIS FOOT WITH HIS BARE HAND-- A PAINFUL MISTAKE. >> SO MY FOOT WAS BURNING, THEN MY FINGERS WERE BURNING. IF YOU EVER GET A BAD BURN, THAT'S WHAT IT WAS LIKE. LIKE GETTING A REALLY, REALLY BAD BURN. >> narrator: ANDERSON WAS LUCKY TO SURVIVE. THE<i> MONSTER QUEST</i> SCIENCE TEAM LED BY DR. JAMIE SEYMOUR IS ANALYZING VIDEO EVIDENCE THAT THESE FLOATING MONSTERS MAY ACTUALLY PLAN WHERE THEY WILL ATTACK. >> IT BECOMES OBVIOUS THAT THESE ANIMALS ARE MAKING CONSCIOUS DECISIONS, IF YOU WILL, AS TO WHERE THEY WANT TO BE. >> narrator: TO PROVE HIS THEORY, HE CONDUCTED AN EXPERIMENT. >> SO WE PUT THESE LITTLE ACOUSTIC TAGS ON THEM AND YOU CAN ACTUALLY TRACK THESE ANIMALS. WHAT WAS REALLY INTERESTING IS IT BECAME OBVIOUS REALLY QUICKLY THAT THE ANIMALS DON'T JUST DRIFT AROUND IN THE CURRENT. THEY'RE MAKING DEFINITIVE DECISIONS TO WHERE THEY WANT TO GO. AND A COUPLE OF THE ANIMALS WE TAGGED ACTUALLY TRAVELED PARALLEL TO THE COAST, UP AND DOWN, FOR SEVERAL KILOMETERS AND THEN MADE A DECISION TO ACTIVELY GO UP THE CREEKS. NOW, THEY WERE DOING THIS ON THE INCOMING TIDES. THEY'D MOVE UP THE CREEK ON THE INCOMING TIDE. THE TIDE WOULD START TO FLOOD, AND THEY'D STOP. OBVIOUSLY GOT OUT TO CURRENT, AND WHEN THE TIDE STARTED TO MOVE IN AGAIN, THEY'D MOVED FURTHER AND FURTHER UP THE CREEKS. >> narrator: SEYMOUR'S EXPERIMENTS SEEMED TO INDICATE THE BOX JELLYFISH RESPOND TO COLOR. >> IT'S NOT SO MUCH THE COLORS; IT'S THE CONTRAST BETWEEN THEM. HAVING SAID THAT, THOUGH, I MEAN, WE HAVE TRIED BLACK AND WHITE AND RED-- FOR NO OTHER REASON, THOUGH; IT'S JUST THE COLORS THAT WE HAD AROUND AT THE TIME WITH A BIG BOX JELLYFISH. AND WHAT'S INTERESTING IS, THEY DON'T SEEM TO BE ABLE TO PICK UP THE WHITE IN THE WATER, AND THEY'LL RUN INTO WHITE POLES. YOU PUT BLACK POLES IN THE WATER, AND THEY'LL TEND TO SWIM AROUND THEM. AND, YEAH, THEY CAN SEE THEM, AND THEY'LL AVOID THEM. BUT INTERESTINGLY ENOUGH, WHEN WE PUT RED POLES IN THE TANK, THE ANIMALS ALL WENT TO THE OPPOSITE ENDS OF THE TANK. >> narrator: THESE RESULTS SEEM TO INDICATE THAT THESE LETHAL PREDATORS ARE FAR SUPERIOR TO NONLETHAL JELLYFISH, GIVING THEM AN ADVANTAGE IN TRACKING DOWN THEIR PREY. THESE MEANS THAT IF BOX JELLYFISH FOLLOW OTHER JELLYFISH SPECIES AND MULTIPLY IN NUMBERS, THE RESULT WOULD BE FRIGHTENING. OTHER EXPERTS THINK A VAST INCREASE OF THE BOX JELLYFISH IS UNLIKELY. >> EVERYONE'S TALKING ABOUT NUMBERS OF JELLYFISH GOING UP, BUT SOME JELLYFISH LIKE THE STINGER BOX JELLYFISH ARE EXTREMELY VULNERABLE TO CHANGES IN SALINITY. SO IF YOU HAVE A LOT OF RAINFALL, IT CAN ACTUALLY KILL THEM, SO YOU MAY ACTUALLY FIND A DROP IN THE POPULATION RATHER THAN THE POPULATION GOING UP. >> narrator: THE<i> MONSTER QUEST</i> EXPEDITION TEAM, LEAD BY DALE PEARSON, HAS BEEN DRIFTING ALONG THE CURRENT JUST OFF THE GREAT BARRIER REEF, SEARCHING FOR BOX JELLYFISH. LITTLE DO THEY KNOW THAT A JELLYFISH HAS FOUND THEM. >> HEY, I THINK WE'RE BEING FOLLOWED. >> GIVE ME A STATUS CHECK ON WHAT YOU CAN SEE RIGHT NOW. >> YEAH, ROGER. TOPSIDE, LOOKS LIKE WE FOUND A PRETTY DECENT-SIZED ONE DOWN HERE. PRETTY BIG. >> narrator: THE DIVERS HAVE COME UPON A JELLYFISH, 2-FOOT ACROSS. >> LOOKS LIKE IT COULD BE PRETTY NASTY, SO WE'RE GOING TO TRY TO FILM IT BUT GOING TO KEEP OUR DISTANCE JUST A LITTLE BIT. OVER. >> narrator: USING EXTREME CAUTION, PEARSON FILMS THE JELLYFISH. THIS JELLYFISH IS A TROPICAL STINGER. THE CAPTAIN INFORMS THE DIVERS THEY NEED TO MOVE ONCE AGAIN DUE TO THE APPROACHING STORM. THE TEAM HEADS BACK TO THE SURFACE. THEY REPOSITION THE BOAT 50 NAUTICAL MILES OFF THE COAST OF TOWNSVILLE IN AN AREA CALLED WHEELER REEF. >> AS THE DIFFERENT CORAL HEADS AND STUFF RIGHT WHERE WE'RE GOING TO BE LOOKING, SO WE'RE HOPING THIS DEEP WATER AREA RIGHT HERE IS BRINGING THE JELLYFISH UP OUT OF THE DEEP WATER AND KIND OF WELLING UP RIGHT HERE. >> narrator: WHILE THE TEAM PREPARES TO MAKE ITS INITIAL DIVE, THE CAPTAIN REPORTS THAT THERE'S ALREADY BEEN JELLYFISH SPOTTED IN THE AREA. THE DIVERS ENTER THE WATER. >> TOPSIDE. COMM CHECK, DALE. CAN YOU HEAR ME? >> TOPSIDE, TOPSIDE. THESE ARE DIVERS. COPY. OVER. >> TOPSIDE, COPY. PAUL, CAN YOU HEAR ME? >> ROGER THAT. WE CAN HEAR YOU JUST FINE. TOPSIDE, DALE. GIVE ME A STATUS CHECK ON WHAT YOU CAN SEE RIGHT NOW. >> TOPSIDE, WE'RE ON TOP OF A CORAL HEAD AT ABOUT 14 METERS. A LOT OF BEAUTIFUL CORAL, A LOT OF WILDLIFE DOWN HERE. AND WE WENT THROUGH A LOT OF DIFFERENT JELLIES ON THE WAY DOWN: RED BIG JELLIES, BELL, ALL DIFFERENT TYPES. SO THERE'S A LOT OF LIFE DOWN HERE. WE'RE GOING TO COME DOWN HERE A LITTLE DEEPER AND TRY TO FIND SOME BIGGER. OVER. WE'RE FINDING MORE JELLYFISH IN THE TOP FOUR METERS. THERE'S A WATER CRAWL. SO PAUL AND I ARE JUST KIND OF NEUTRAL AT ABOUT FOUR METERS, DRIFTING WITH THE CURRENT HERE. NOTHING OF ANY MAJOR SIZE. NO MONSTER-SIZED ONES YET THOUGH. OVER. >> narrator: THE DIVERS HEAD UP FOR MORE OXYGEN WHEN PEARSON BECOMES ENTANGLED IN TENTACLES. THE EVIDENCE SUGGESTS MAN AND NATURE HAVE COLLIDED TO CREATE A MONSTER IMPOSSIBLE TO CONTAIN OR CONTROL. THE WORLDWIDE POPULATIONS OF JELLYFISH ARE MULTIPLYING LIKE NEVER BEFORE. FROM JAPAN TO THE EAST COAST OF THE U.S., JELLYFISH HAVE MOVED IN AND ARE TAKING OVER. THEY'VE CLOGGED POWER PLANTS, RUINED FISHERIES, AND EVEN KILLED PEOPLE. THIS RESEARCHER SAYS THERE'S LITTLE TO STOP THEM ONCE THEY INVADE. THIS MAN NEARLY LOST HIS LIFE AFTER BEING STUNG BY THE VENOMOUS BOX JELLYFISH. THIS MAN BELIEVES THEY POSSESS SOME FORM OF INTELLIGENCE, POSSIBLY MAKING THEM AN EVEN GREATER THREAT TO HUMANS. DALE PEARSON AND THE<i> MONSTER QUEST</i> EXPEDITION TEAM HAVE BEEN SEARCHING FOR MONSTER JELLYFISH OFF THE GREAT BARRIER REEF. AS PEARSON SURFACES, HE BECOMES TANGLED IN JELLYFISH TENTACLES. >> SO I PULL MY FACE AWAY FROM THE FRAME TO LOOK TO FIND OUT WHERE IT IS, AND IT'S ALREADY WRAPPED UP ALL AROUND MY HANDS, AND I DON'T WANT ANY PART OF THIS, SO I'M TRYING TO GET AWAY AND IT JUST STARTS BREAKING INTO PIECES ALL OVER LIKE A WET PAPER TOWEL, YOU KNOW WHAT I MEAN? AND YOU'RE JUST LIKE, "OH, MAN." ON THE WAY BACK TO THE BOAT, I WAS JUST CHECKING MYSELF OVER AND OVER AND OVER AND OVER AND OVER JUST MAKING SURE. I WAS, LIKE, "MAN, I DON'T WANT NONE OF THAT STUFF ON ME WHEN I GET BACK TO THE BOAT," YOU KNOW? >> narrator: EVEN THOUGH HE'S SURE IT WASN'T A DEADLY BOX JELLYFISH, PEARSON FEELS LUCKY. >> IT DIDN'T GET THROUGH ANY OF MY GEAR. IT DIDN'T GET THROUGH MY GLOVES. >> narrator: THE COMING STORM FORCES THE TEAM TO CONTINUE TO MOVE SOUTH. THEIR NEW LOCATION IS OVER A NEAR CENTURY-OLD SHIPWRECK. >> THE IDEA IS THAT WE'LL GET IN THE DEEP WATER WITH THE WRECK. IT'S GOING TO PROVIDE SOME STRUCTURE FOR ANIMALS AND FOR FOOD FOR THE JELLYFISH, SO WE'RE HOPING THAT THIS AREA MIGHT HAVE A BIGGER JELLYFISH. I'M RIGHT BEHIND YOU, WAGS. >> ROGER THAT. >> TOPSIDE, COMM TO DIVERS, CAN YOU GUYS HEAR ME OKAY? >> ROGER. WE NEED TO YOU TO MAKE IT LOUD AND CLEAR. BOTH DIVERS ARE ON BOTTOM. WE ARE 2-9 METERS, RIGHT BY THE BOW. >> narrator: PEARSON HAS SPOTTED A 300-POUND GROUPER SWIMMING IN THE WRECK WHEN SUDDENLY HE ENCOUNTERS A DANGEROUS PREDATOR. >> narrator: THE DIVERS HAVE SPOTTED A MASSIVE BULL RAY. >> YEAH, THAT THING IS HUGE. >> narrator: THE DIVERS ARE ENCOUNTERING PLENTY OF MARINE LIFE. THEN OUT OF OF NOWHERE... >> TOPSIDE, THIS IS DALE, COULD YOU REPEAT LAST TRANSMISSION? TRANSPARENT. I'M NOT SURE WHAT SPECIES. >> narrator: THEY'VE COME UPON AN AUSTRALIAN SPOTTED JELLYFISH. IT'S NEARLY FOUR FEET IN DIAMETER. >> IT'S PRETTY LARGE COMPARED TO THE LAST ONE WE SAW, THOUGH. PRETTY GOOD SIZE. OVER. BE CAREFUL, WAGS. BE CAREFUL. >> narrator: THE TEAM RUNS LOW ON OXYGEN AND ENDS THEIR DIVE. >> AS SOON AS WE GOT DOWN THERE, WE GOT A JELLY ON THE BOW, SO THAT WAS SWEET. AND WE SHOT THAT, THEN WE MOVED ALONG. WE GOT ALL THE WAY TO THE STERN, AND WE FOUND ANOTHER JELLY ON THE STERN. A BIGGER ONE. >> narrator: THE WEATHER REPORTS INDICATE THE CYCLONE IS APPROACHING AND WILL MAKE THE AREA DANGEROUS FOR THE DIVERS. >> THE CONDITIONS FOR FINDING THE JELLYFISH HAVE DEGRADED CONSIDERABLY. WE WERE HOPING THAT THERE WAS GOING TO BE BETTER VISIBILITY. THE RIVERS HAVE BEEN DUMPING MASSIVE AMOUNTS OF FRESHWATER AND IT'S LOWERED THE AMOUNT OF SALINITY IN THE WATER. >> narrator: THE CYCLONE HITS THE AREA HARD. THE 70 MILE-PER-HOUR WINDS CAUSED $22 MILLION IN DAMAGE OVER FOUR DAYS. DR. JAMIE SEYMOUR SURVEYS THE COASTAL AREA WHERE THE CYCLONE'S EFFECTS ARE STILL BEING FELT. >> WELL, THIS IS ATYPICAL WEATHER FOR DOWN HERE ON THE EAST COAST OF AUSTRALIA, CERTAINLY UP IN THE NORTH. I MEAN, THESE WAVES AND THINGS HERE. WE'VE JUST HAD A CYCLONE COME THROUGH. >> narrator: SEYMOUR SAYS THAT THE WEATHER MAY EXPLAIN THE SEEMING LACK OF JELLYFISH. >> IT'S THE BIGGEST WET SEASON WE'VE HAD FOR MAYBE 15 TO 20 YEARS. WHAT IT'S DONE IS IT'S DECREASED THE SALINITY, IT'S INCREASED THE WAVE MOMENT, IT'S MADE THE WATER ALL MURKY. BOX JELLYFISH DON'T LIKE THIS. I MEAN, THEY LIKE PLATE GLASS WEATHER. WHAT HAPPENS IN THIS, NOT ONLY DO WE GET THESE WAVES AND THINGS WHICH PUSHES THE ANIMALS OUT OFFSHORE, BUT THE SALINITY DROPS. AND NORMALLY WE'D HAVE BEEN TALKING 33, 34 PARTS PER THOUSAND. IT DROPPED TO ABOUT 18 PARTS PER THOUSAND. SO ONE OF TWO OPTIONS ARE TO STAY HERE AND DIE, OR THEY MOVE OFFSHORE. >> narrator: SEYMOUR EXPECTS THE MONSTER JELLYFISH TO RETURN IN GREATER NUMBERS. >> NORMALLY SORT OF AROUND JANUARY, FEBRUARY IN THESE CONDITIONS THEY ARE PRIME FOR BOX JELLYFISH. IT'LL BE NICE AND FLAT. AND ON A BEACH, THIS SORT OF LENGTH FROM HERE THROUGH TO THE STINGER NETS, I'D PROBABLY EXPECT TO SEE 15 OR 20 JELLYFISH. THE THING IS, THE NUMBER THAT YOU SEE INSHORE IS ONLY A SMALL PORTION OF WHAT'S OUT THERE BECAUSE A LOT OF THEM ARE FURTHER OUT ON THE WATER THAT YOU DON'T SEE THEM. >> narrator: THIS<i> MONSTER QUEST</i> EXPEDITION HAS YIELDED SOME INTERESTING EVIDENCE. THE DISCOVERY OF AN OUT-OF-PLACE STARFISH IN THE SEA OF JAPAN SEEMS TO INDICATE A RISE IN WATER TEMPERATURES. AND THE INCREASE IN THE TEMPERATURES COULD BE THE REASON FOR THE RISE IN JELLYFISH POPULATIONS. THE SCIENCE TEAM'S TEST OF DR. SEYMOUR'S THEORY THAT THE DEADLY BOX JELLYFISH IS ABLE TO DISCERN PREY MEANS THESE CREATURES MAY INDEED POSSESS SOME FORM OF INTELLIGENCE MAKING THEM AN EVEN BIGGER THREAT. >> THE REAL IMPACT JELLYFISH CAN HAVE IS WHEN THEY BECOME REALLY, REALLY ABUNDANT. WHEN THEY'RE REALLY DENSE IN THE WATER, THAT'S WHEN THEY CAN SORT OF SWEEP THROUGH A REGION OF THE OCEAN. >> AT 180 SECONDS TO KILL YOU, IF THAT DOESN'T-- IF THAT DOESN'T WORRY YOU WHEN YOU GO IN THE WATER, THEN YOU'RE JUST NOT THINKING CLEARLY. >> WITH THE NUMBERS OF JELLYFISH BLOOMING IN DIFFERENT PARTS OF THE WORLD, I DON'T THINK THERE'S ANY DOUBT THAT IT'S INDUCED BY HUMANS. IT'S NOT SOMETHING THAT'S JUST-- MOTHER NATURE, FOR THE WANT OF A BETTER WORD, HAS CAUSED. I MEAN, THESE THINGS HAVE BEEN IN BALANCE FOR YEARS AND YEARS AND YEARS, AND IT'S ONLY BEEN WHEN WE GET INVOLVED AND WE CHANGE THAT BALANCE THAT THAT SORT OF THING OCCURS.
