Lake Constance - Wilderness on the Water - Go Wild

[Music] loved by people sought out by wildlife powerful wild and constantly in motion the guests are international [Music] they may change the lake but it has space for all of them the four million people who live here don't disturb the wildlife [Music] an ocean in the center of europe lake constance is big [Music] and full of surprises [Music] [Music] at the end of the winter everything about this lake that links austria germany and switzerland seems calm but there's tension in the air suddenly they're here thousands tens of thousands [Music] starlings [Music] they're on their way from the south to their breeding grounds in northern europe now they need a safe place for the night [Music] as dusk descends they gather at the reeds beside the lake [Music] they descend from the sky [Music] and the reeds swallow them up [Music] some of the gnarled fruit trees on germany's hari peninsula are well over a hundred years old [Music] the land around lake constance has been cultivated and inhabited since ancient times [Music] yet it's full of wildlife the white stalk wintered in africa now he's here and he's hungry he'll find plenty to eat in the water meadows a frog will do nicely but right now in spring the frogs have something else on their mind [Music] females [Music] love is blind [Music] nobody cares about style what matters is being first [Music] the competition from other males is enormous the first to pin down a female and cling to her back has good chances of perpetuating his genes [Music] [Music] the eggs are fertilized in the water everyone wants to be first the greater his proximity to the female the greater the chance of him being the one who fertilizes the spawn the eurasian coot comes bearing gifts materials for the nest the red crested potsherds should have gone by now but they're staying [Music] some brides can be rather choosy the black-headed girl is looking its best it loses the black cap when it molts in summer [Music] water galore with the snow melt in the mountains the water level in lake constance rises a metre and a half now the meadows and reed banks around the lake fill up they are part of the extensive reed areas where the rhine joins the lake a nature reserve and resting place for migrating and resident birds [Music] black-headed girls live here all year round [Music] they like to live on inland waterways and reed belts are particularly popular as breeding places [Music] this large colony of girls has only a small space to share [Music] among black-headed girls building the nest is a man's job [Music] construction material may be recycled from an abandoned nest [Music] used components are selected and pre-treated to make them easier to work with [Music] in their springtime finery the sexes are almost identical the female is just a little smaller black-headed girls only stay together for a single season these two great-crested grebes have made a date for a mating dance the mating rituals of the great crested grieb can last for weeks now things are getting serious [Music] the delicately coordinated head movements make it clear they've fallen for each other [Music] the mallards are already one step ahead male and female grebes not only look similar but also face each other at eye level when courting [Music] among black-headed girls the distribution of roles is more traditional she expects gifts and hopefully he has brought something by regurgitating food the male displays his qualities as a nurturer later on the same techniques will feed their young like the black-headed girls great-crested grebes also stay on the lake all year round but this couple is restless a black kite has returned from its winter quarters in morocco it's looking for prey [Music] there may already be chicks at this breeding colony at the lake there are no young here yet but still the entire colony takes off to confuse the raptor safety in numbers [Music] the rhine flows into lake constance with enormous power the huge amounts of silt and sediment carried from its source in the swiss alps keep the delta in a state of flux [Music] over the last hundred years the rhine has advanced so far into the lake that the bay between bregenz and lindau has been reduced by almost fifty percent [Music] miasburg once home to a prince bishop is over a thousand years old the shore of lake constance is densely populated the island of mainau is an exception in the ice age lake constance was created by the rhine glacier the rhine flows through the lake and continues on its way 100 kilometers further on it looks as though the lake ends here at the town of constance in fact it opens up again and encircles its largest island right now [Music] only later does it become increasingly narrow at stein amran the lake reverts to a river from here it continues as the rhine until it makes its point very clearly at schaffhausen the gigantic water mass of lake constance descends with a deafening roar past the rhine falls the rhine still has a long way to go through germany bordering france and then through the netherlands till it flows into the north sea near rotterdam the cascades at the rhine falls are an almost insurmountable obstacle for fish only one creature refuses to be deterred the eel as a youngster it entered the rhine at the north sea and swam inexorably upstream [Music] eels once came to lake constance in their thousands born in the atlantic in the sargasso sea of bermuda adult eels turn from salt water into freshwater fish [Music] they reach lake constance after 5 000 kilometers not all in the water the eel is a creature between two worlds it slithers like a snake across damp meadows absorbing oxygen through its skin that's how the eels could scale the rhine falls eels can live up to 50 years once as their life neared its end they would swim back to their birthplace in the sargasso sea eels are migratory fish that prefer flowing water [Music] nowadays their route is blocked by power stations and concrete embankments today the eels in the lake are caught in the atlantic of the french coast and are released in lake constance [Music] above the surface there's also hope for new life the coots are sitting on their eggs they share the time on the nest and they both fetch construction materials on a 50 50 basis constant improvement with varied results the reeds provide protection nourishment and plenty of building material one of the smallest mammals in the world lives here the harvest mouse water below sky above and in the middle a perfect habitat of reeds the harvest mice build their spherical nests between the stalks high enough to protect them from the high water soon more young will be born until then they're busy renovating the nest this delicately nibbled reed stalk will make a soft bed for the youngsters the material has to be woven tightly the newborn mice are tiny they only weigh one gram it's the harvest mouse's special pores that make it a master builder they work almost like human hands the reeds give the harvest mice everything they need to survive this piece is a bit cumbersome but very practical the seed provides food and the rest is building material their fur is the same color as the reeds perfect camouflage [Music] they're virtually invisible even to the sharp-eyed black kite [Music] black kites are the eco-police of lake constance the first to spot injured or dying animals sometimes they steal from other birds or attack themselves here seagulls are trying to grab the kite's prey me around the lake there's not only pristine nature my now the famous flower island was planned 150 years ago as a living park that would constantly reveal itself in new clothing nothing is left to chance a million tourists meet a similar number of tulip bulbs year after year [Music] bees have only gained by the presence of human beings the more flowers the greater the variety of food on offer [Music] but not all animals have gained from the proximity of humans beavers were extinct in lake constance by the end of the 17th century but now there are unmistakable signs of the beavers return the brigance flows into lake constance through water meadows that are the ideal beaver habitat young beavers start off afraid of the water their parents have to push them into the lake to accustom them to the new environment resettlement projects help bring the beaver back to lake constance this male is fetching material for the nest because the female is expecting babies of the three eggs in the grieb's nest only one remains the first storm of spring has almost destroyed the nest great crested greebs build their nests right on the water with floating plants like water lilies this couple found another solution a plastic bottle to stabilize the nest after the storm this nest is too low if it sinks any further the egg will get too cold [Music] another storm is brewing if this egg is destroyed the couple will have no chicks this year [Music] [Music] all the birds are busy trying to secure their brood the nest of the great crested gribs is almost submerged even the large floating nests of the swans threaten to capsize [Music] [Music] elsewhere on the lake there's little trace of the storm the beaver's nest their lodge is well protected the female beaver is preparing to suckle her young intensive grooming helps keep her coat insulated a glandular secretion called custodium makes it water resistant even the youngsters know what to do [Music] though they don't immediately find the right place for the milk [Music] the mother waits patiently soon enough the growing beavers will feed only on plants [Music] conservation zones give the beavers a chance to settle in constance again [Applause] outside it's raining again the lake has a high level of humidity so violent thunderstorms often follow a downpour rain doesn't bother the greeds as long as the nest survives they've even managed to keep the egg warm and dry their brood is safe for the moment [Music] normal life resumes in the bird colonies with occasional disputes [Music] the brooding period of the grieves is almost over if the weather stays calm for a few more days the chances are good the weather at lake constance is very changeable the alps cool down rapidly while the lake retains heat that makes for some surprises [Music] fine feathers interlock making the potsherd's outer coat firm and dense [Music] the green finch's feathers are similar and even finer [Music] the potchard's coat remains water-resistant regularly greased with secretions from a gland on the bird's rump the soft layer of down under the contour feathers provides a warm safe place for the newly hatched chicks in conservation areas like rajpits dead wood from fallen trees offers a new habitat piles of clam shells have been washed up by the storm these are asian clams they were first sighted in lake constance at the turn of the millennium since then they've spread rapidly on the sandy floor of the lake [Music] zebra mussels arrived in the lake back in the 1960s probably as stowaways on the hulls of ships they attach themselves with sticky threads smothering branches and even indigenous mussels which are gradually disappearing from the lake [Music] carp search for insect larvae and worms among the mussel beds [Music] tadpoles feed on algae and the algae flourishes on the excrement of the zebra mussels [Music] coots are fond of exotic mussels though they only hatched a few days ago the chicks are also looking for food this has not gone unnoticed under the water a catfish edges closer it's feelers that barbles have taste buds and it senses the sound waves created by the chicks the cygnets are also in danger in the open water they are easy prey but close to the shore the reeds stymie a surprise attack the catfish withdraws the grebes are parents their frantic efforts to protect the egg paid off the young great crested grieve has a distinctive red cap on its downy head now there are youngsters everywhere on the lake and the battle for food is in full swing the black kites have no fear of becoming prey themselves but they're under stress some would rather steal from their neighbors than go hunting themselves if both chicks are to survive there's little rest for the older birds the young only learn to hunt at the age of three months [Music] slowly summer comes to lake constance at the rhine delta farmland flanks the nature reserve colorful siberian sword lilies adorn the water meadows in june the spectacle is short-lived immediately after pollination they fade these are the hot days on the lake now the birds must share the water with a particularly invasive species humans the small great crested grieve is a teenager rather than webbed feet groups have skin flaps on their front toes holidaymakers don't even have that just water wings on warm summer evenings there's music in the air at lake constance a bird catcher as darkness descends the floating stage comes to life the notes of the bregenz festival merge with the gentle splashing of the waves [Music] papagino for mozart's magic flute will hardly be a threat to the frog king [Music] be [Music] here [Music] lake constance provides drinking water for 5 million and a habitat for 34 species of fish in the last century fishing flourished in lake constance high phosphate levels in the water stimulated plant growth water rich in nutrients provided fish with an excellent diet the construction of purification plants made the water cleaner too clean for some good quality water means less nutrition for fish and stocks began to decline on the other hand this meant more light reached deeper into the lake changing the flora and fauna under the water now waterfowl can find more food a fisherman has become something of a rarity but he won't be ignored young common girls have already learned that fishermen gut the fish on the way home throwing the entrails overboard [Music] summer lasts a long time at lake constance the huge mass of water absorbs the sun's warmth and only releases it gradually the town of lindau inhabited since roman times [Music] first cultivated by the monks of rajinao monastery this island later passed into the hands of the teutonic knights my now [Music] into [Music] [Applause] [Music] [Music] here on my now nature has been tamed each plant has its place in this integrated work of art according to color age and seasonality [Music] the steady warmth of the glass house is home to many exotic butterflies like this orange tip [Music] or a large tree nymph butterfly wings describe an arc for both lift and thrust the blue morpho butterfly has a wingspan of 10 centimeters the red rim uses its long proboscis to reach deep into the calyx the julia butterfly finds the nectar the same way mists herald the arrival of autumn the migratory birds leave and arrive the cormorants remain much to the annoyance of the fishermen [Applause] the common potsherds have just arrived back they will spend the coldest time of the year here before flying north again in spring [Music] in winter a quarter of a million waterfowl inhabit this comparatively mild lake at the edge of the alps the birds gather closer together than they did in the mating season permanent residents like mute swans search for food alongside the winter guests [Music] early morning another newcomer does his rounds raccoons that escaped from cages have spread rapidly especially in germany some years ago they reached lake constance [Music] in europe raccoons have virtually no natural predators they themselves are ruthless nest robbers not everyone is happy about the influx of this wily creature [Music] the protected wetlands of the rhine delta offer a habitat for other wild animals deer find food and shelter in the forests nearby [Music] in the area around miasburg the grape harvest has begun red wine is also produced here that's unusual so far north the reason red wine grapes flourish so close to alpine glaciers is connected with the lake itself [Music] with depths of up to 250 meters this is a huge body of water it extends so far that a very special phenomenon can be observed boats vanish on the horizon only the sails remain the curvature of the earth creates this effect as on the ocean [Music] the gigantic mass of water has heated up during the summer and becomes a radiator in the autumn when evenings are cold elsewhere at lake constance they're merely cool [Music] under cover of darkness a raccoon ventures very close to humans the grapes are not too high here and the dog is locked up in his garden [Music] at night you just can't beat an excellent sense of smell this time its nose leads it straight to a garbage bag [Music] sensitive front paws with five independent fingers allow a delicate investigation of the booty with all the time in the world [Music] shallows at the edge of the lake make perfect hunting grounds for waders like the grey heron [Music] they stay at lake constance all year round [Music] mostly solitary hunters they gather in groups only where food is especially abundant [Music] in the autumn and winter months hunting for fish in the shallows is a piece of cake crusaders normally visit central europe during the winter but they stay here all year round they're on the red list of endangered species and are strictly protected when they find a shell of small fish the gussanders hunt in a group their hooked bills with rows of serrated teeth are fiercely efficient a goosander devours over a quarter of a kilo of fish a day unsurprisingly they would be ruthlessly hunted in late autumn the water level of the lake drops significantly the different colors of the reeds show how high the water was in summer it reaches its lowest point in the winter a new generation of harvest mice has now grown up the female can bear young up to six times a year perhaps that compensates for its short life span no more than a single year when the young leave the nest they must learn to climb immediately but moving through this landscape deftly takes some practice [Music] their ingenious prehensile tail functions as a fifth paw at between five and seven grams they're light enough to live on the reed stalks this new generation will have to survive the winter [Music] as the reeds become golden the water leaves the reed belt on the lake floor coots search for seaweed the chicks born in spring are now grown up outside the mating season coots live in large colonies [Music] small signals keep the peace [Music] [Music] [Applause] in years gone by red crested potsherds were only winter guests attracted by the rich supply of food for them the mating season starts in november this is a creature that inhabits two worlds like the eel the red-eared turtle lives in water and on land it likes to sun itself on the beach it's a new arrival here too the first specimens were probably pets released into the lake [Applause] when winter comes the turtle settles on the lake bed with temperatures just above freezing it slows its metabolism and hibernates until spring [Music] in [Music] see [Music] [Music] lake constance trout become active during the winter months they inhabit the depths of the lake feeding on crustaceans and small fish at four years of age they become sexually mature then they start making their way back to their home waters where they'll spawn [Music] but for that they need unregulated rivers one of the natural waterways available to the trout is the bregenzach here they can find spawning grounds with shallow fast-moving water and gravel beds their eggs need water with high oxygen levels and an ideal temperature of two to six degrees when she's found suitable spawning grounds the female digs a pit and deposits the eggs the male immediately fertilizes them with his sperm the young trout will spend their first year here in the spawning grounds then they'll make their way back to lake constance [Music] very rarely perhaps once a century lake constance freezes over completely [Music] that's a good thing for fish and deer they can find food all year round abandoned wooden huts by the lake are especially inviting the harvest mice are undisturbed in their winter shelter here they can hibernate with breaks to stock up on food insect larvae can be found in dry reed stalks big energy snacks for little mice [Music] in spring after a short stopover the lap wings head on to their northern breeding grounds [Music] the western curlews are also passing through [Music] the cycle begins again the guests bring new life to the region [Music] the sunlight becomes stronger with every passing day the southern slopes of the mountains are already clear of snow [Music] in the trees among the reed beds the cormorants are rebuilding their nests from the previous year [Applause] this year the melt water from the alps arrives early in the wetlands the water level is rising as is the testosterone level the water frogs start looking for mates again unnoticed by the frogs spring is about to break out under the water as well [Music] frogs flee the water seeds [Music] spawning has begun in the shallow water for the cop males jostle females to get as close as possible to the spawn and to be first to fertilize it the reed belt is a battle zone [Music] spring in the wildlife wilderness of lake constance bringing new life to the heart of europe [Music] you

Channel: Go Wild

Views: 55,162

Keywords: orf universum, documentary, blue chip, natural history, secrets of nature, planet earth, wildlife, free documentary, watch full documentary, nature films, wildlife films

Id: ZWYG94DpI8k

Length: 51min 8sec (3068 seconds)

Published: Wed Oct 20 2021