The Abundance Of Life Living On The Coast | Our World

strange satellites fly through the dark heavens but these beautiful cone jellies are in fact swimming in water [Music] this colorless odorless fluid envelops more than two-thirds of our planet earth so perhaps our world would be better named planet water [Music] where light penetrates the upper ocean the sea going population flourishes in extraordinary diversity [Music] water quenches more than thirst delicate gills breathe dissolved gases hungry plants and animals feed on circulating nutrients [Music] but which are the very richest waters of life surprisingly the answer is not the deep ocean but a considerably rougher neighborhood the coastline [Music] [Music] so the coasts are a complex matrix where earth air and water collide animals from each environment interact at these rich margins and powerful currents and waves can transport them from one zone to another [Music] these shores prove the ocean's power to deliver to carry pioneers like the marine iguana its ancestors were washed up onto the galapagos islands having most likely traveled from the coast of south america almost a thousand kilometers [Applause] away unlike the iguanas some of the residents here seem to have mastered the turbulent seas galapagos sea lions [Music] [Music] sea lions haven't broken their ties with the land even though they move more easily in water they live in a sort of halfway house and still return to the shore to relax and raise their families they are not the only animals to give up mobility out of the water for expertise in it unique flightless cormorants have abandoned life in the air for the harsh rocks and sea they even caught on the water and courting means nest building the best nests are lined with seaweed and it's the male's job to come up with the goods back to the sea again the female will actually place the weed and she patiently awaits the next offering [Applause] much of the seaweed he brings his mate will be used to line the nest but not all of it some of the greenery is simply a gift the avian equivalent of a bunch of flowers the offering is probably an attempt to strengthen the pears close bond [Applause] each galapagos bird species plays its own distinctive mating game a waved albatross woos a female with some impressive beak bashing some species respond to a nod others to fancy footwork up in the cliffs blue-footed boobies show off their brightly colored feet to prospective mates using color as a lure isn't just for the birds male marine iguanas also make a splash during the mating season their skin breaks out in red sending a bold signal to any available females there's little for the iguanas to eat on these virtually barren volcanic islands so they feed mostly in the sea where they can graze on algae but the water is so cold that even the sturdiest iguanas can stay submerged for only a short time before they need to warm themselves on the rocks these waters provide a living but it is not an easy one the surf sets a pounding rhythm along rocky coastlines [Music] gentler waves lap the coast of borneo like every coastline this shore also pulses to an even slower rhythm the rhythm of the tides here each low tide exposes the strange aerial roots of mangrove trees this bizarre forest with its roots in salt water enables proboscis monkeys to live at the very edge of the sea during low tide it's much easier to make their way to fresh feeding grounds by walking along the exposed beach even though it's a bit like crossing a bed of nails the coast is clear it's feeding time for all the beach dwellers time to emerge from their burrows and go about their twice daily business the monkeys scout the mangrove forest moving from tree to tree in search of tender new shoots mud skippers leave their sandy burrows to browse on bits of algae that wash up with every high tide the mudskipper is a very unusual fish it can store water in its gills so it can come out of the sea to feed low tide is the time to do a bit of housekeeping fiddler crabs have also emerged to forage for algae every activity is dictated by the timetable of the tides even war male fiddler crabs joust for supremacy male mudskippers also face off in battles for territory the tide turns and the water rises with startling speed the shoreline changes once again and the fiddler crabs prepare for the deluge [Music] high tide is a mixed blessing it delivers fresh deposits of algae but the waves can also wash the crabs out into deep water the mud skippers run the same risk the rising water has caught out the proboscis monkeys now they must pay the penalty and wade awkwardly through waist-high waters as always these sociable animals travel as a group proboscis monkeys are primarily vegetarians so their food is not rich in energy like other browsers they take every opportunity to feed their coastal home has been refreshed by the tides elsewhere the relentless rhythm of the tide attacks the coastline eroding the shore but a mangrove forest actually builds land the trees tangled roots trap sediment which becomes the basis of new soil as the mangrove forest creeps forward larger trees colonize from behind tides seem like a local event and in some ways they are high and low tides occur at different times along different shores but they happen all around the planet a global phenomenon created by a distant presence as the moon glides silently around the earth its gravitational pull drags two bulges of water after it on opposite sides of the world these bulges form the two high tides each day and in their wake two low tides follow low tides uncover a hidden supply of food along sandy shores beaches can be full of tiny organisms we never see shorebirds know they are there but they must be quick to take advantage of the feast once the water has reached its lowest point it's only a moment before it begins to rise again protecting its rich cargo of food [Music] one high tide triggers the arrival of thousands of strange visitors to the east coast of north america horseshoe crabs they have been coming here every year since before the dinosaurs walked the planet the crabs leave the water only briefly to spawn a new generation that happens only at this time of year when the gravitational pull of both moon and sun creates the highest tides the female crabs release millions of eggs to be fertilized by the males we do not know why or when the crabs first came to this shore but we do know that birds had yet to evolve the ritual remains the same but times have changed now every year shorebirds gobble up the eggs nearly as fast as they are released the horseshoe crabs continue to lay their eggs but so many eggs are released that even after the birds eat their fill there are enough left to establish another generation of crabs and it's only because of this glut of eggs that the birds have the strength to make their arduous annual migrations [Music] tides affect every coastline but they are surface movements the power of the tides pales in comparison with the power of deep ocean currents currents speed across the ocean floor driven by differences in temperature churning up the ocean as they do so when deep cold water currents hit the hidden edge of a continental shelf they thrust upwards creating a special zone called an upwelling although these are waves of cold water upwelling zones are often far more fertile than tropical seawater the cold currents bring cargos of nutrients with them which they drag up from deep on the ocean floor the upwelling zone off the coast of california nourishes giant kelp plants [Music] these zones are the savannas of the sea and like the african plains they support multitudes from tiny phytoplankton to graceful harbour seals [Music] so [Music] [Music] [Music] [Music] one small patch of this giant forest can be a sea otter's whole world sea otters spend almost their entire lives bobbing amid the kelp often entwining themselves in the fronds that float on the surface in order to rest or sleep without drifting away a sea otter needs to go ashore only during very severe storms these endearing marine mammals are extremely intelligent especially when it comes to finding food the underwater forest floor is where the otters find their prey shellfish and sea urchins an adult sea otter must eat the equivalent of 25 of its own weight each day in order to maintain its body heat in these chilly waters that's the equivalent of a human eating about 100 hamburgers stones make useful tools to bash a meal loose this shellfish is an abalone human fishermen often need a crowbar to pry one from a rock [Music] this isn't a tidy process cormorants often come scrounging for scraps the otters must return to the surface to breathe and eat at last a chance to eat in peace more or less the cormorant keeps popping up to keep an eye on his meal ticket california sea otters also use stones to get into their food on the surface this otter puts a stone on its stomach to pound the shell against while other otters use a tapping technique the right stone is such a useful tool that some even carry a favorite one stashed in an armpit between meals [Applause] the upwelling zone provides everything the otters need food shelter even a safe place to raise their young but it's the cold deep water current and the microscopic life it brings that sustains them all [Music] [Applause] on the other side of north america another deep ocean current creates spectacular fertility the atlantic coast of newfoundland is home to the largest gannet colonies in the world the gannett's eyesight is so good that they can actually spot shells of fish from high above the sea they plunge towards their targets from heights of up to 40 meters [Music] during nesting season the cliffs are studded with mating pairs [Music] [Applause] although there are thousands of gannets fish are so plentiful in these waters that enormous flocks of gulls can also thrive alongside it makes for a crowded coast fish form the bulk of seabirds diets so many seabirds will breed when the fish are most plentiful often this coincides with when the fish themselves are breeding drawn together in huge numbers to special spawning grounds the supply of fish on this coast is especially abundant in spring when the capelin come to spawn for these little fish mating is a very risky business in order to secure the safety of their young thousands of breeding pears swim right up onto the beach the female burrows into the sand to lay her eggs as the male wraps around her to fertilize them [Applause] their eggs will be relatively safe here but the adults are not most of them will die in the process stranded on the shore but their death throes do have a purpose they have spawned a new generation a nutrient-rich current can support the life of an entire coastline steadily delivering its vital cargo of food across millions of years the cliffs of patagonia in south america show the effects of just such a current fossilized shells are embedded in the cliffs the remains of clams and giant oysters that lived here 20 million years ago the cliff itself is a relic from a time when south america was an island people have never colonized this remote and barren coastline so these waters offer marine animals a safe haven a southern right whale brings her calf into a sheltered bay the young whale already weighs four tons but even at this size in the open sea it would be vulnerable to predators and to stormy weather its mother can tend and feed it more easily in shallow water [Music] but there's little food for her in the bay and the calf needs feeding it must gain about 10 tons and grow 8 metres in its first few months of life before it can head for deeper waters fortunately the mother whale has prepared for this retreat she fed out in the deep ocean and has gained enough weight to nurse her enormous baby she probably weighs at least 50 tons she has to in order to provide her calf with 125 liters of milk each day the oceans support whales not only by providing massive quantities of food the water also supports them quite literally whales can only grow so large because they're buoyed up by water whales are not the only marine mammals to seek out this coastal sanctuary southern sea lions come ashore here to raise their young they come to this coastline for the same reason the whales do the land is devoid of humans and large predators they're a raucous bunch the males spa for territory and access to females the females have little choice but to put up with the jostling even though their heads are layered with a built-in helmet of thick fat many of the males bear the scars of past encounters it's the young pups who are at risk if they get too close to the action this one i better find its mother fast the pups are born on shore one year after conception it's a brief respite on land the pups begin to go into the water when they're just three to four weeks old each mother and pup must be able to find each other so the pup can feed somehow they managed to pick out each other's distinctive calls in all the din magalanic penguins also come to the patagonian coast to mate and breed the penguins are prepared to pay a high price for the safety they find here it's 2 400 kilometers from their wintering grounds out in the atlantic this is the first time they've been near dry land in six months but this coast makes an ideal nesting ground one parent can tend the youngsters while the other catches fish the young penguins have voracious appetites they have just six weeks of feeding and growing on shore before they begin their ocean-going lives a parent returns with a full load of fish the delivery system is simple and direct regurgitation the only large land animals to live here are guanacos descended from the long extinct north american camel the guanacas can just about eke out a living on this barren strip of land which stands in stark contrast to its abundant coastal waters it's time for the penguins families to hit the beach their trek to the sea proves these animals are built for water not land [Music] so [Music] thousands of penguin pairs and their new young are preparing to return to their atlantic feeding grounds but before they set off the youngsters must brave the cold water for the first time [Music] there's no turning back now young sea lions make the same rite of passage to their ocean going life some won't even survive their first swim orcas killer whales are intelligent animals they have learned that this is the time of year when the young sea lions take to the water [Music] a lucky escape [Music] [Music] [Music] orcas are the largest of the dolphin family and like many other dolphins they hunt in family groups the sea lions are up against a deadly team [Music] the orcas retreat with their catch it might seem to be a cruel sea for the sea lions but for the orca family these are very definitely waters of life most of the sea lion pups will survive to reach deeper water and the coastline will be quiet again until the seasonal visitors return along every fringe of land water supports life but not every coast lies in a temperate climate south of patagonia lies a coastal boundary that is far less distinct and far less permanent in antarctica during large parts of the year the coastline is not land but water itself in its solid form ice the daily penguins find respite from freezing water only by coming up onto frozen water but this ice is melting and breaking away from the rocky shore it's summer and the end of the breeding season like the magellanic penguins in patagonia this large colony has been busy fattening up their young ready for the cold antarctic waters but this colony was not always as close to the shore as they are now in fact the reason their youngsters are so close to the sea when they're big enough to leave is not as obvious as we might think it is the result of careful planning when the adults arrived in the cold spring winter sea ice had spread out all around this shore pushing the water's edge far away from their rocky breeding grounds the only way to reach them was to trek inland and as we know penguins aren't built for walking snow surfing is the easiest way to travel once they reach their destination the adelies pair off and mate it will take a month for the eggs to hatch and each parent will work a 12-day shift looking after them while the other parent feeds out at sea after hatching the chicks have only 60 days to fatten up before they're ready to leave and during this time rising temperatures melt the sea ice bringing the shore closer to them in this way the adelies save their young an unnecessary trek to the sea and a waste of all the energy reserves they have built up the penguins closest neighbors are weddle seals their young have already been born and the baby seals must quickly gain thick layers of blubber if they're to survive in the freezing cold their mothers provide them with some of the richest most fattening milk in the animal world but a mother must leave her baby behind in order to feed herself hunting below the ice sheet is dangerous a seal often finds her breathing hole rapidly freezing over she uses specially adapted teeth to grind away at the ice only when the hole is large enough to stay open for a time will a sealed dive and begin to hunt it's a repetitive but essential struggle her life and the life of her pup depend on her ability to return to the surface youngsters have to wait on the surface at this age a pup is too buoyant to swim to any depth and it can't begin to hold its breath as long as its mother can the antarctic seems unforgiving but even here there are mercies to be found with spring the platform of sea ice frozen sea water begins to break up the solid coastal boundary rapidly retreats entire cliffs of glacial ice shatter this is freshwater ice formed from thousands of years of snowfall the coastline of an entire continent is completely redrawn next winter it will be redrawn yet again the seasonal change along the antarctic coastline is dramatic and rapid but water constantly shapes and reshapes every coastline waves grind shores to grit and sand and shift vast amounts of material around the planet the sea shapes every shore every island individually even two adjacent stretches of coastline can be completely different on this island in the falklands penguins arriving on the rocky side had better be prepared for a bumpy landing [Applause] those arriving on the other side of the same island can make a much easier landing here the sea has deposited its contents sam these new arrivals are already enjoying a day at the beach while back at the other side their comrades are still coping with the surf and slippery rocks so the slim margin where the land meets the sea has many faces surely some of the loveliest profiles are in the tropics here a coastline may have an ally in its defense a coral reef a reef slows incoming waves as a speed bump slows speeding cars but these defenses are alive a coral reef is a colony of tiny animals over the years new generations add fresh layers and the reef becomes a beautiful buttress of living rock sheltering corals attract tropical fish in every colour of the rainbow [Music] it's not just the corals that have hard coatings so do crabs but not all of them are born with them the hermit crab with no hard shell of its own has to scrounge for shelter as the crab grows it must search out a larger dwelling place if the shell's already occupied well an eviction notice can be served but the general rule is if the shell fits wear it good every resident of the reef must create new generations there are no exceptions [Music] undercover of darkness the corals begin to reproduce triggered by a full moon they release millions of eggs and sperm the water turns milky with the makings of new corals [Music] fish will eat many of the eggs but a few will grow and add their own skeletons to the reef others will drift away the eggs are at the mercy of the currents they will go wherever the ocean takes them perhaps to other tropical waters where they may begin a new reef this is one part of the ocean where the coral eggs stand no chance of survival it's a bizarre world at the very bottom of the sea but even here in these lightless depths water supports life boiling hot sulfurous fumes rise up from deep rifts in the earth's crust it's in just such poisonous conditions however that some of the first life on earth may have been born primitive bacteria not unlike the microscopic life that lives here today if this is the birthplace of life where is the birthplace of land of new coastlines at hot spots in the earth's crust like those in hawaii eventually the volcanic eruption slows and the lava cools to form solid land huge plumes of steam rise up where the lava hits the sea a new coastline is in the making [Music] colonizers arrive carried on the winds that sweep up and over the new land rising mists supply the land with life-giving rain plants too rapidly colonize the land [Music] the land is transformed by lush vegetation but it can only survive if there is water this is the miracle of life beyond the coasts salty sea water becomes sweet fresh water when rain clouds form over the sea leaving the salt behind fresh water with the power to nourish and shape the land [Music] so [Music] hey [Music] [Music] hawaii's spectacular cliffs and valleys were created by flowing water water that originated in the sea [Applause] [Music] [Music] sea birds travel thousands of kilometers across the oceans so an island makes a vital resting point but once an island forms it's at the mercy of the ocean over time even a mountain of an island can be dismantled by rainfall by a rise in sea level and by the waves pounding at its shores midway island is the westernmost in the hawaiian chain midway once towered out of the water now it stands just four meters above sea level at its highest point half of the island is likely to be underwater in just a hundred years everything changes however long those changes take but for now this low-lying island is a crucial rest spot for sea birds laysan and black-footed albatrosses come to midway to take refuge and to mate the young albatrosses born here are creatures of the air and water not the land unlike their parents they are prisoners here until they learn to fly the albatross's long wings make it an expert glider but they make it very hard to flap its way into the sky this is a dangerous place for a novice flyer tiger sharks know when it's time for the fledglings to make their practice flats an adult gets away the young birds gangly wings are a liability [Music] [Music] the sharks take a serious toll of the fledgling birds but many are born and the population is not damaged by the predation the albatrosses have depended on midway for thousands of years if the island disappears beneath the waves future generations will have to find a new breeding ground perhaps the oceans will offer up another island for them [Music] the oceans support thousands of marine species but sea water is only part of a life-giving cycle liquid salt water is transformed into vapor by heat and leaves its salt behind in this form water is at the mercy of the winds far from the sea fresh water falls from the clouds on dry and thirsty soil rain sustains plants and animals across every continent the salty waters of the ocean are transformed into fresh waters of life

Channel: Our World

Views: 25,673

Keywords: wildlife, wildlife documentary, natural history, earth, environment, documentary, documentaries, animals, nature, animal documentary, full documentary, nature documentary, planet earth, our world, wild animals, global warming, climate change, natural habitats, our planet

Id: SocZ-v_EIa0

Length: 50min 58sec (3058 seconds)

Published: Mon Jul 25 2022