Eagles - The Whole Story S01E04 - The Secrets of Nature

hello monarchs of the air magnificent and proud with fierce beacon talon the great birds of prey who rule africa's skies of all vertebrates the raptors that hunt by day have the keenest eyesight airborne vultures can see a carcass from a phenomenal height around three thousand feet from one thousand they can smell it and down they swoop vultures have a typical raptor's sharp hooked beak but because they eat carrion they have no need of the eagle's powerful killing talons a secretary bird does this terrestrial raptor hunts small animals on the ground and it stamps them to death most owls fly at night and share the daylight raptors keen eyesight but they need their ears more than an eagle does to hunt all diurnal birds of prey share an eagle's ability to grasp kill and tear with talon and beak and all raptors have eyes that are large and round and face forward eagles are the biggest birds of prey it's a raptor characteristic that females tend to outsize males the female marshall weighs over six kilos she's a heavyweight for an eagle she sports boots of feathers right down to her feet most eagles have an impressive wingspan a marshalls is over two and a half meters nearly the length of a grand piano to minimize weight an eagle's bones are like honeycomb inside a strong yet light design the crowned eagle is africa's heaviest and most powerful able to kill even adult bushbuck its plumage is a lovely red brown and black a raptor's great glory is probably its eyesight the means of locating prey eagle eyes see over twice as well as human eyes they have special in-flight protection that moistens and cleanses a transparent nictitating membrane like diver's goggles under the feathers behind its eyes lie its ears at the base of the beak is the seer an area of bare skin where the nostrils are located sense of smell is weak but the beak is strong and designed to cut tear and crush eagles are very territorial birds and do not like competition from others on their patch like most juvenile eagles the young butler changes his clothes when he grows up swapping dull brown feathers for flashy black but he has to wait till he's seven long ago when the world was young there lived a proud and vain fish eagle as they grubbed for food the monkeys heard the great bird calling and watched it swoop through the air see how handsome i am how my feathers shine cried the eagle i am beyond compare the true ruler of the earth the monkeys couldn't believe their ears if the lion king of the beasts should hear the boastful evil he would be wild with anger so naturally one monkey sneaked off and told him when the lion heard for himself the eagle's boasts he was indeed furious but what could he do he couldn't get at the fish eagle it was way out of reach on top of a tree and today all the animals still wonder who really rules the earth but there's no doubt as to who rules the sky high on a mountain in south africa's eastern cape a pair of black eagles have a nest they're very economical birds because they tend to reuse the same cliffhanger and as is usual among eagles they made for life they're a very democratic pair for they share home renovation each flies in sticks and twigs to bring the nest up to scratch two fresh eggs are already safely installed in a high-rise home that seems to get higher and higher most eagles instinctively cover old rotting food scraps with fresh green foliage this may also cushion the eggs treading carefully so that she doesn't crush them mother gets ready to settle in she turns her eggs regularly to oxygenate them and make sure they have all-round exposure to her warmth for 44 days she'll be sitting plenty of time to rearrange the furniture nearby a pair of starlings watches with interest even if she's hungry the female will not desert her post until her mate gets back for his shift she's impatient to clock off and eat thieving baboons and ravens lurk in this neighborhood so the eagle parents won't leave their eggs unattended when the male swings interview she's off and the starlings seize their chance they're in like a flash but it's maggots and insects on meat scraps they want their raids are swift they'll be gone before the owner gets home father's shift he curls his lethal talons to avoid accidentally piercing the eggs but it's the female who's in for the long haul she does most incubating she may even sit nearly 24 hours on the go the first chick is out it took its time to hatch from first crack of the shell to complete exit was two days during which time it kept cheaping to its mother snow white new fluff will soon go and in just four days the chick will have its muscles and coordination under control this white down is not very warm mother must make up for it and she still has to hatch her other egg she takes as much trouble with it as with the chick so fathers come to check progress small enough in these first few days to fit the palm of a hand and hungry the chick has run out of the fuel supplied by the egg now it needs meat a little leftover hyrax would be fine but it can't yet help itself mother must feed meal times are her concern the male may bring meat but she only occasionally lets him feed their chick her razor-sharp beak tears small chick-sized pieces sometimes though her own hunger is overwhelming and sometimes she gets her measurements all wrong and just to show what a full-grown eagle can choke back she swallows the leftovers lock stock and barrel that's something to aspire to all gone time for quiet digestion while she's added she can tweak the carpeting but today she has the fidgets like any shift worker she must have her regular brakes sitting motionless for hours would make a human seize solid the chicks feather blanket soon reappears and just as well for the eastern cape mountain weather is changing getting colder bad news for chick and egg but now mother is cracking this one using her beak as delicately as tweezers there's a four day gap between the hatchlings and the second is much smaller but both receive equal attention uncharacteristic weather and severe cold are particularly dangerous for the weaker second chick the first attacks it in instinctive behavior that's typical of black eagles survival of the fittest at its harshest there'll be no rival for food or parental care but the cold has already done its work black eagles often lay a second insurance egg though only one hatchling may survive that's enough though to maintain the family line rock hyraxes are the number one black eagle delicacy the birds usually nest near them it's a straightforward eating arrangement three months on and this is the same trick it's a startling transformation appetite matches size and father and mother have their work cut out airlifting meals gone is the helpless hatchling the eaglet has a strong yellow beak to shred flesh though sometimes it looks as if it doesn't know where to start they've seen to their youngsters needs so now they can see to their own but a discreet watcher is close by either the parents didn't spot it or it's one of an earlier year's brood so they tolerated it instinctively the juvenile tries to shield its food at first the newcomers intentions are not clear and there's little apparent animosity all too quickly it becomes obvious it's not here for a family visit and it's goodbye breakfast lunch and dinner it's a tough world at the top of the aerial food chain africa's eagles have an eclectic appetite what they eat depends largely on their size and where they live long-crested eagles inhabit the sub-sahara they like to spot small morsels from a good high point a mouse appropriate for a small eagle this isn't the moment to break cover oh an eagle has a rapid metabolism that needs daily fueling every bit of mouse will vanish except larger bones feet and fur those the long crested eagle will regurgitate eagles don't usually overeat too much weight isn't good for takeoff but occasionally they do and they're grounded until they've digested an african hawk eagle a bird of forest edge and savannah woodland slightly larger than the long crested eagle so able to attack something weightier than mice a short silent swoop feet outstretched to grab the scrub hair will never know what struck this place has thieving opportunists so the eagle keeps a nervous eye out it spreads its wings to hide its kill because scavengers won't miss much so better make a move but the hair's too heavy to fly off with another strategy is needed spread wings also help stop the eagle falling over a low growing thorn bush it'll give the nervous bird some privacy a ground floor restaurant for an eagle that might rather eat in a tree a night of full moon and the leatherback turtles are hatching at bunga neck near saint lucia on south africa's eastern seaboard baby turtles have battalions of enemies though fewer at night so they need to make a break for it before sun up not all got away before dawn and the more light the slimmer the chances of a clean getaway yellow-billed kite migration coincides with turtle hatchings and a bird can fly faster than a small turtle can crawl however not every hunter seems wide awake yet this hunter though has lined up a target but turtle shell is slippery stuff a good grip this time african fish eagles can bully and steal so the kite makes it an in-flight meal eating on the wing is tricky it takes a cool head and good coordination the sun is now high and the turtle flood is a trickle at least the kite has its hands full and won't bother them even when they hit the water eager mouths are waiting but this is their element and they can swim for it this is the expert turtle snatcher the pads of a fish eagle's feet are covered with spickles rough serrations that help it grip slippery customers losses on land may be heavy but enough hatchlings get through to keep the generations going in patches of coastal forest where raphia palms grow lives a strange bird of prey it's a bit of a mix between eagle and vulture the vulturine fish eagle is also called the palm nut vulture its eating habits are rather peculiar for a bird of prey because its vegetarian as well as meat eater it can catch and kill and its scavengers but this unique eagle vulture is also a fruit and nut eater tucking into palm nut husks oddly it tosses away the oil-rich kernel but this means it unintentionally plants its own food crops an eagle gets around of course on its wings it's designed to stay up with minimum effort this one's about to discover the power of flight it's the black eaglet her long flight feathers had shafts full of blood when they first grew now they're hollow strong and ready to flap her parents are away more and more often time for her big push but maybe not just yet another moment or two it's an awfully long way down a few pre-flight checks to prime the muscles flight is instinctive parents cannot come along for the ride and instruct the juvenile must pilot solo so is it liftoff the first flaps are just for the feel of a new experience and now on your marks get set go well that worked another pilot wins her wings this landing strip's a new experience too like a spiky trampoline learning to fly and land is decidedly hit or miss now the eaglet meets her first thermals she hasn't a clue at first as to how to exploit them they fly her all over the place either by design or by accident she's found one to take her home here's how the experts do it the rising air currents that create thermals strengthen as the ground warms so some birds of prey can't get up in the morning until these aerial elevators are strong enough to give them lift an eagle's most important feathers are its wing tips these it can move and spread like fingers for stability and strong wind catching a thermal means the eagle saves energy it needn't flap much adjusting wing position slows it down or speeds it up angled back and close to its body makes it dive like a short-winged jet fighter but no jet can maneuver like an eagle fighter pilots like to show off their aerobatic skills and so it seems to eagles the bataller eagle took its name from the old french for a tightrope walker and when you see how it moves in the air you know why battlers don't have the usual long eagle tail feathers to use as rudders to stay balanced and stable this bird uses its wings like a tightrope walker's pole that's how it got its name battlers are long-haul specialists they can fly for nine hours with hardly a flap at speeds of 80 kilometers an hour and cover 300 kilometers all in one day birds may be descended from early reptiles or from dinosaurs but there's an increasingly solid theory that they are dinosaurs slightly reptilian-looking archaeopteryx was the oldest fossil bird ever found it lived 110 million years ago some scientists believe however that it didn't give rise to modern birds but what came before archaeopteryx new evidence points to a common ancestor for crocodilians and birds pseudo sushil a crocodile ancestor walked on hind legs and much of its internal structure was like a primitive birds early toothed mouths gradually became beaks scales feathers four legs wings primitive birds may have used claws to clamber up trees or cliffs from where they could leap down on their prey according to a new theory this is how flight evolved it challenges the theory that birds developed flight as a result of running and flapping their primitive wings until they lifted off eagles inhabit many places and every continent except antarctica etosha in south west and africa is one of the more difficult homes it's part of a great white salt pan over six thousand square kilometers in size for most of the year it's parched and arid there are no permanent rivers or pans in winter there's only water from springs where all kinds of animals gather lapid-faced vultures aren't the only winged scavengers here a battler eagle will also eat those who die from hunger and thirst two battler eagles have flown in now though for a drink on another hot etosha day feathers insulate against cold and heat much needed here in the madness month of october so called because temperatures climb into the all 40s for an eagle able to turn its hand to scavenging life is not hard when the grazing goes and the ungulates start dropping an eagle's home is its irie usually built below the crown of a tall tree or on an inaccessible cliff ledge some are reused over several decades some weigh at least as much as a family car the crowned eagle builds its nest in the forest canopy crowned eagles may eat other high living animals like monkeys but this prey that's often four times heavier than an eagle sometimes has accidental allies to a crowned eagle white-necked ravens are neighbors from hell if they're in the same airspace the ravens mob the eagle there are two ways to shake them leave the territory or land he lands away from the nest the couple's precious chick must be kept hidden from such dangerous neighbors as ravens there's an old saying never foul your own doorstep as mothers happy to demonstrate the chick is not impressed just hungry mother plaintively summons her mate who should be out finding the family supper and sure enough he has a monkey mother intuitively turns back to hide the chick and keep it warm father may have brought food but he won't be allowed to feed the chick that's mother's department she tears off easy to swallow pieces or maybe not so easy to swallow she seems not to know what to do will her chick choke fortunately no if it could get that down it's clearly destined for great things the vast inland delta of botswana's okavango is populated with hippo and with literary and fish eagles probably the most territorial african raptor all through the year they patrol their waterfront beat in the ocavango where there's so much fish this may be no more than 400 meters they sit glued to the water for hours fish fining along near the surface are in the danger zone even an expert fisherman usually casts several times before landing a catch the field is clear for a yellow build kite to see if it can do better success depends on a lightning strike talons extended at the last second this many eagles if they call at all have a surprisingly small voice for their size they call for three main reasons courtship territorial defense and contact between pair or family eagle eyes miss few signs from other eagles body language age color of plumage aggression an eagle may puff out feathers to regulate its body temperature or to threaten the same is true of an open beak the scorching kalahari in the mating season and a female marshall eagle is calling from her nest these eagles mate for life so they don't put much effort into annual courtship displays calling is the usual no-frills prelude to mating at the top of a kalahari acacia a tawny eagle pair have a nest a larger male sees a smaller one close by and goes to intimidate it while the female watches the male makes his meaning quite clear by non-aggressive but nevertheless threatening body language the lonely cry of the fish eagle is one of africa's most evocative sounds characteristically this noisiest of eagles throws its head back to call it can even do this in full flight for many people it is the sound of africa being at the top of the food chain makes raptors very vulnerable quantities of dangerous chemicals used in farming accumulate in their bodies and affect their ability to reproduce they often crash into power lines deforestation has deprived many of homes people steal their eggs for sale and pied crows don't only mob and pester eagles they steal too eggs and chicks left by themselves just a little too long may not be there when the eagles get back the rock kestrel is very aggressive towards birds like pike crows it doesn't want them in its a territory eagle is a bit too big for it to chase but where a black eagle has its nest there may be a rock kestrels close by the bigger bird of prey makes an excellent security guard for the smaller eagles are a marvel of the natural world where the mastering thermals on colossal wings scanning the ground with fierce sharp eyes or just displaying their striking good looks and haunting calls these great birds are part of the very essence of untamed africa i am i am i am

Channel: The Secrets of Nature

Views: 103,130

Rating: 4.6559138 out of 5

Keywords: orf universum, documentary, blue chip, natural history, secrets of nature, planet earth, natura, naturaleza, documentales, wildlife, grandes documentales

Id: Gi8N79g3hQE

Length: 50min 59sec (3059 seconds)

Published: Sun Oct 11 2020