- In an endless and dark expanse floats a peaceful blue oasis. That is our vision of the Earth. And yet our planet is far more complex. Air, earth and water are the planet's driving forces. These forces shaped the many cycles that have created the planet's amazing natural diversity. (DRAMATIC MUSIC) In the oceans,... on the continents... and in the atmosphere,... water covers more than two-thirds of the earth's surface. Its unique characteristics provide the foundation for all forms of life on the planet. (DRAMATIC MUSIC CONTINUES) Without water, Earth wouldn't exist. Captions by Sophie Pearce. Captions were made with the support of NZ On Air. www.able.co.nz Copyright Able 2021 (EERIE MUSIC) Water covers more than 360 million square kilometres of the Earth's surface hiding a vast, secretive world, largely invisible to the human eye. On average, the world's seas are 3500m deep, and they form an immense space subject to its own natural laws. The various bodies of water that cover the planet have different temperatures, different pressure levels and different chemical compositions. Thanks to its many unusual characteristics, water creates the conditions for life to develop and thrive. The oceans teem with a diversity of life forms, but those sea dwellers are unevenly distributed ` a single coral reef may contain as many species as found in the entire North Atlantic. Just a few creatures can claim citizenship to entire oceans. Sperm whales, constantly on the move, feel right at home in all of the world's oceans. The world's largest predator grows up to 20m long and weighs up to 60 tons. (ATMOSPHERIC MUSIC) These gigantic mammals also dive to depths of more than 2000m and have the world's largest brains. They may spend up to an hour underwater before returning to the surface to breathe. (GENTLE, SERENE MUSIC) Naturally, a creature of this size requires large amounts of nourishment. A sperm whale can eat up to a ton of food a day. Sperm whale mothers and their calves may congregate in large groups. Social interaction plays an important role. (SERENE MUSIC CONTINUES) The whales communicate with each other through songs and physical contact. (WHALES CLICK) They may even hunt together in the depths, coordinating the pursuit of their prey. (CLICKING CONTINUES) Like so much else in their lives, their behaviour occurs deep below the surface, far from prying eyes. (WHALES SQUEAK, CLICK) Ocean life is in constant motion, its inhabitants driven by forces beyond their control,... the complex systems of currents, like the mighty Gulf Stream. This simulation shows the swirls and sweeps of the surface currents over two and a half years based on data collected from satellites and monitoring stations around the world. This global conveyor belt connects four of the planet's five oceans, creating a gigantic, world-spanning circuit. The currents exchange energy and matter and are largely driven by the characteristics of the water itself. Cold water is heavier than warm water and saltier water sinks towards the seabed. These powerful physical forces transport thermal energy and biomass around the planet. This, in turn, distributes nutrients, helping create pockets of life in specific ocean regions. (LIVELY, SWEEPING MUSIC) It all begins with innumerable, tiny life forms that nourish billions of larger organisms,... that feed gigantic schools of fish. (SWEEPING MUSIC CONTINUES) Humans soon learnt to take advantage of these bountiful areas,... (MOTOR CHUGS) ...but we're not the only ones. The dolphins have set their sights on the tuna that follow the swarms of smaller fish. (DOLPHINS SQUEAL) The fishermen share their interest in tuna and attempt to follow the dolphins. More and more of the intelligent marine mammals joined the chase ` dolphins may form pods of several hundred. (GENTLE, RHYTHMIC MUSIC) (GENTLE MUSIC CONTINUES) These are spinner dolphins. They are aptly named. (GENTLE MUSIC CONTINUES) As yet, scientists have been unable to explain why the dolphins perform these pirouettes. Maybe they're communicating or trying to shake off parasites. Or perhaps they're just having fun. (SERENE MUSIC) Around the world, fishing takes many forms. (INTRIGUING MUSIC) Fishermen along the southern coast of Sri Lanka have one of the most incredible techniques. Rather than use boats, fishermen here perch on stilts. Hasanur explains this unusual fishing method usually works well. But now several hours of patient fishing produces only a small catch. This wasn't always the case. Whales and huge schools of fish are not the only creatures to travel great distances. (SWEEPING MUSIC) This green sea turtle has spent years, maybe even decades, riding the currents and crossing the high seas. (GENTLE MUSIC) Now she heads for land. She must build up her energy reserves for a monumental task ` a task 20 years in the making. She dives one last time before heading to shore. Her destination is the same beach where she was born. How are these turtles can find their way back to their birthplaces after two decades of roaming the seas remains a mystery. After dark, the turtle crawls ashore. She awkwardly drags herself across the sand with her flippers. She digs a hole and deposits her eggs. The carefully-buried eggs will incubate for seven weeks. Job done, the turtle drags herself back into the sea. Several sea turtle species often share the same beaches. While one species buries its eggs, the offspring of another start to hatch. This little olive ridley sea turtle is just a little faster than its siblings. The freshly-hatched reptiles instinctively know which way to go. Perhaps the young turtles can sense the slope of the beach or see the shimmering spray of the breaking waves. They immediately move towards the sea. It's a long, arduous journey. They have to take a break every few steps to rest. However, they have no time to lose. They race against the sun. (GENTLE, SWEEPING MUSIC) The young turtles have to reach the water before dawn ` daylight brings danger. Danger also lurks out at sea. Large schools of fish attract unwelcome attention from below and from above. The sea eagle's vision can penetrate the glittering reflections on the water's surface ` all the better to target individual fish. But sometimes catching the fish is the easy part. (EAGLE CRIES) A second attempt. Today, the sea eagle faces an additional difficulty ` (INTRIGUING MUSIC) a rival eagle. (EAGLE CRIES) (DARK, DRAMATIC MUSIC) (EAGLE CRIES) (DRAMATIC MUSIC) Although sea eagles mainly eat fish, they sometimes enjoy a little variety ` this time, a sea snake. The bird now has to reach land without being bitten by the venomous reptile. More than 90% of the ocean's creatures are barely a few millimetres long. Despite their minuscule size, larvae and crustaceans are the preferred food of some of the largest ocean inhabitants. Amongst them, the world's largest fish ` the whale shark. They grow up to 13m and can weigh 12 tons. (TENSE MUSIC) To feed, they open their wide mouths and filter plankton from the water. (GENTLE MUSIC) Whale sharks may suck in more than 6000 litres of water an hour, pushing the water out through their gills. Filter pads separate any creature larger than 2mm. An entourage of pilot fish accompany the large sharks, eating whatever the whale sharks leave behind. Another group of oceanic drifters is responsible for the existence of all life on the planet, not just in the seas. Phytoplankton provide much of the world's oxygen. This animation shows the distribution of full plankton groups over the course of four years, taking into account both wind and water currents. The red zones in the polar regions reveal the dominance of diatoms, a form of algae. These microscopic organisms not only produce most of the planet's oxygen ` they also form the first link of the food chain. Without them... They live in polar regions for a reason. The large ice streams deliver their livelihood. (GENTLE MUSIC) When ice chunks break off the edges of glaciers, this makes sure that life continues on the blue planet. (ICE CRACKS, WATER SPLASHES) (SEA BIRDS SQUAWK) (DARK, ATMOSPHERIC MUSIC) The ice chunks carry sediment, eroded and pulverised by the glacier into the sea. The sediment allows the diatoms to reproduce on a giant scale. But plankton isn't strictly polar. (ATMOSPHERIC MUSIC CONTINUES) It thrives wherever large rivers carry sediment and nutrients into the sea. The world's rivers transport 9 million cubic metres of water to the ocean every second. (GENTLE MUSIC) 80% of the silicon in the oceans comes from the rivers, which erode rock and carry it across continents to the coasts. On their journeys from the mountains to the seas, these rivers create some of the most fertile landscapes in the world. A family of giant otters is excited ` the young otters are about to attempt their first swim. Giant otters are fast, naturally acrobatic water creatures, but practise makes perfect. This pup's not so sure. (OTTER SQUEAKS) Eventually, it takes the plunge. The young otter soon feels right at home in the water. (OTTER SQUEAKS) However, the older otters still keep a close eye on the beginners. The youngsters still need time to get the hang of it. A little bit of encouragement helps. Eventually, they'll fish as quickly as their parents. Otters hunt in groups. (GENTLE GUITAR MUSIC) When the water level goes down, the concentration of fish rises. The more fish, the easier the hunt. (GUITAR MUSIC CONTINUES) Fully-grown giant otters eat around 3kg of fish a day. (OTTER SQUEALS) The hungry beasts don't like to share. The otter withdraws into a nearby stream. (WHIMSICAL MUSIC) Finally, it's time for a hearty meal. But maybe not. Fresh water is on its way. Every year, almost 500,000 cubic kilometres of rain falls on the Earth's surface. (THUNDER RUMBLES) Rivers and lakes collect more than one-third of it. (ATMOSPHERIC MUSIC) In some regions, large expanses of forest remain flooded for weeks. (TENSE MUSIC) Surprisingly, that doesn't stop some trees from bearing fruit. And that's not the only surprise. The seeds of the rubber tree seem doomed in these floods. How can they fulfil their purpose? The impact excites the fish. For most of them, the manna from heaven is too large. But not for the tambaqui, which spends a lot of time swimming below the rubber trees. The big fish cracks the seeds with its powerful jaws and teeth. (GENTLE MUSIC) Both fish and tree reap the benefit. The detour through the tambaqui's digestive system spreads the seeds throughout the forest underwater. When the flooding begins to recede, the water dwellers must adapt,... sometimes in bizarre ways. (RUMBLING NOISE) Male yacare caiman's demonstrate their strength with thunderous calls that cause the water to quake. (RUMBLING NOISE) The display of power not only looks impressive, it also creates infrasonic sound waves that carry far across the murky waters. (CROCODILE SNARLS) The sound of his head smacking the surface of the water produces higher frequencies that announce his location. He makes these sounds to convince female caimans that he's mating material. The capybaras observe the ritual from a safe distance. They are the world's largest rodents and males may weigh up to 50kg. The young caimans appear tiny next to the fully-grown capybaras. The capybaras research the mud for the remains of plants. During the dry season, hunger drives them closer to the crocodiles. (FUNKY MUSIC) Approximately 14,000 cubic kilometres of water in the form of vapour and precipitation circulate in the atmosphere every day. Far greater forces are at work in the world's seas. (GENTLE, ATMOSPHERIC MUSIC) The gravitational pull of the moon affects entire oceans. Every rotation creates a mountain of water that travels around the planet. Exact satellite measurements of the oceans' surface reveal the rise and the fall of the tide. The topography of the seabed plays a significant role. These forces are only visible to the naked eye in regions where shallow waters cover large areas, sometimes creating fascinating habitats. Mangrove roots work equally well underwater and on land. High and low tides occur twice daily, but the exact time changes from day to day. The moon requires almost 25 hours to circle the earth. It's gravitational pull inexorably draws the water out of the mangrove forest. Fish flee from their hiding places among the roots. Within just a few hours, the water will have vanished completely. The water has receded from the mangroves and from the beach. The newly-exposed mud reveals a lively coming and going. (RHYTHMIC MUSIC) Thousands of colourful fiddler crabs emerge to search the sand for tiny, edible particles. The abundance of crabs attracts the attention of other animals. (PIG SNUFFLES) To the bearded pigs, the tiny crabs are little more than a snack. (PIG SNORTS) But that's enough to draw the pigs out onto the mudflats. The crab-eating macaques also appear at low tide. (MACAQUES CHIRP) Unlike the pigs, the primates have to keep their sensitive fingers away from the sharp crab claws. (INQUISITIVE MUSIC) Sometimes greed trumps caution. (MACAQUE CHIRPS) (FUNKY MUSIC) Fiddler crabs spend much of their time avoiding the pigs and the macaques, but they also have other business ` finding a mate. The male fiddler crabs major claw is the largest sexual organ in the world in relation to body size. The female has her pick of well-endowed males. She's in no hurry. (GENTLE MUSIC) The male's share some sexy choreography. (GENTLE MUSIC CONTINUES) The female makes her selection and the crabs retreat into the burrow to mate. The tides create other fascinating habitats along steep, craggy coastlines. When the tide goes out, hollows in the rocks remain filled with water. (SOFT, SERENE MUSIC) These tidal pools provide a window into this world until the tide returns. Residents must deal with extreme changes in temperature, acidity, salinity and oxygen levels. Currents and breaking waves don't make life any easier. The force of the water in the breaker zone can be deadly, washing away any creature unaccustomed or unprepared. These crabs have settled in comfortably among the waves. Red rock crabs' streamlined bodies and powerful legs allow them to cling tightly to the rocks. They brave the waves so they can eat the algae that appears when the tide comes out. During high tide, the crabs wait in safety for the waters to recede again. As soon as water levels fall, they rush back to the algae. However, danger lurks in the tidal pools. (TENSE MUSIC) The crabs have no choice but to cross the water,... (TENSE MUSIC BUILDS) ...which grabs the attention of the hungry octopus. The crabs follow the same route every time the tides change, and the hunters know where to wait for their prey. A moray eel slides over the rocks, hoping for an opportunity to pounce. The octopus blends into the background and approaches unnoticed. The moray eel, on the other hand, has to find a hiding place. Only an inattentive crab could fail to spot the eel's sharp teeth. Moving fast, the crabs can actually walk on the water. But can they outrun death? (TENSE MUSIC CONTINUES) The crabs react quickly... only to trip the next trap. Now it's the moray eel's turn. The surviving crabs make it to the rocks and begin to feast on the algae. In just a few hours, the tide will come in again and the predators will get another chance. The moon phases also cast their power further out to sea, where tidal currents transport enormous amounts of plankton. The impact of these currents is particularly strong in warm, shallower oceans where corals flourish. 1400 fish species live in the waters off the coast of New Guinea, more than in the entire North Atlantic Ocean. Many of them survive on plankton. (ATMOSPHERIC MUSIC) Some are small fry, as one might expect. However, larger submarine life forms, like giant manta rays, also gorge themselves on plankton as they cut through the water with their 7m-wide wings. The large sea creatures also visit the reef for another reason. Fish leave the reef to feed on the rays' skin parasites. The coral reef is a cleaning station, and the manta rays return regularly for a healthy grooming. It takes a lot of fish to clean a large manta ray. The lunar tides deliver the plankton that feed an army of fish of all sizes. These fish will sometimes form huge schools. The anchovies attract larger predators ` the fast, elegant mobula rays. These rays hunt together, corralling the small fish and forcing them towards the reef. (BLUESY GUITAR MUSIC) (GUITAR MUSIC CONTINUES) Once they round up the anchovies, the rays attack. (GUITAR MUSIC CONTINUES) They open their mouths wide and plough through the schools of anchovies repeatedly. The anchovies regroup after every attack. Then the cycle begins again. Most of Earth's ocean habitat is inaccessible to humans. We know more about the surface of the moon than we do about much of the seabed. The Western Flyer is one of the world's most advanced deep-sea research vessels. (INTRIGUING MUSIC) Its remotely operated submersible, the Doc Ricketts, can descend to 4000m and bring life forms back to the surface without causing them injury. The vehicle plunges into the mysterious depths. From the control room, the team from the Monterey Bay Aquarium Research Institute searches for previously unknown life. - Nice. - The light frequently falls on creatures that look as though they have come from another planet. Many of them create their own light to communicate in the total darkness. Some jellyfish use their light as bait. (GENTLE MUSIC) The researchers have to bring the animals to the surface to study them. The rare sea creatures are gently sucked into the remote-controlled containers. A vampire squid. - Even with it in... There. Yes! (LAUGHTER) - A viper fish. - Perfect. - (SNICKERS) - Oh, look at` Ohh. - And even a deep sea dragonfish. It's no mystery how this fish got its name. This is one of the few dragonfish ever observed in the wild. Even fewer have been captured alive. - Go ahead. Hit it. - Get it. - Yes! - Yay. - Oh my gosh. (RHYTHMIC MUSIC) - These creatures all share one characteristic ` they are fascinatingly bizarre. The yellow-green eyes of the barreleye fish peer upwards... allowing it to look for prey through the translucent crown of its head. The barreleye is extremely rare, as is the Histioteuthis, or strawberry squid. This cephalopod is also known as the cock-eyed squid thanks to its large upward-looking eye. The remote worlds of the deepest oceans still promise much to discover. Some creatures connect these inaccessible depths with the somewhat more familiar upper ocean. (WHALE CALLS) Among them is the largest animal to ever inhabit this planet ` (WHALE CALLS) (GENTLE, SWEEPING MUSIC) the blue whale. (SWEEPING MUSIC CONTINUES) Blue whales can be found in all of the world's larger oceans. These giants may grow up to 30m in length and can live for a century or more. (WHALE CALLS) In the broad expanse of the ocean, they are truly in their element. (GENTLE, DRAMATIC MUSIC) (WHALE CALLS) (DRAMATIC MUSIC CONTINUES) (WHALE CALLS) Captions by Sophie Pearce. Captions were made with the support of NZ On Air. www.able.co.nz Copyright Able 2021