One 150 million years ago,
as dinosaurs approached their golden age,
one group evolved along new and revolutionary lines.
Although they retained many of their reptilian characteristics,
they acquired extraordinary new ones...
..feathers.
Feathers helped with insulation
and display.
But they offered something far more valuable.
The power of flight.
And for birds, that changed everything.
Birds have the freedom of the skies, to travel further and faster than any other group of animals
and to seize opportunities in all corners of the planet.
But this freedom brings many survival challenges,
which birds must tackle at pivotal moments in their lives.
Flying demands enormous skill and effort,
and nowhere is that more evident than here, in the foothills of the Peruvian Andes.
This female hummingbird hovers with precision in her quest for nectar.
Her wing and tail design allow her to fly in any direction.
But the male has a real problem flying.
And this is why
he's weighed down with two super-long tail feathers, tipped with cumbersome discs.
This is the marvellous spatuletail hummingbird.
and these are his flags with which to seduce a mate.
Waving them back and forth takes a lot of effort,
even from the comfort of his perch,
but to win her heart he's got to go up a gear.
He must show her how well he can fly but it's exhausting work.
It's so demanding he can only stay airborne for a matter of seconds
before he needs a rest.
He's struggling to impress her, so one last try.
The extreme effort and energy needed to hover means hummingbirds can only fly in short, sharp bursts.
But most birds need to stay airborne for considerably longer,
and must find far more energy-efficient ways to get around.
Here in the Simien mountains of Ethiopia,
at a breathtaking altitude of 15,000 feet,
lives a supreme aerial maestro.
The lammergeier.
This youngster glides on air currents rising from the mountain slopes below.
His nine-foot wingspan can carry him hundreds of miles a day
in search of animal carcasses, with precious little effort.
He watches out for other airborne scavengers, like these griffon vultures.
They lead him to some commotion on the cliffs, and maybe the chance to feed.
But this youngster is not the only lammergeier to spot the opportunity.
So too has this adult.
The vultures quickly strip the carcass clean.
It seems he's too late. But in fact he's timed his arrival perfectly.
There's no meat left
and that's exactly the moment that the lammergeier has been waiting for.
It's bones he's after.
The young lammergeier too homes in on the carcass.
Bones contain rich marrow fat,
but extracting it is not easy,
especially when the bone is a solid four kilos and too big to swallow.
But lammergeiers have an extraordinary solution, thanks to their flying skills.
Soaring up on thermal air currents and positioning the bone parallel
to his body to minimize drag, he soon reaches the perfect height.
From here he glides to a place he knows
where he can deal with the bone,
where there are giant rock slabs sit on the lip of an escarpment.
The bone is smashed.
The juices in his stomach are more corrosive than battery acid.
They dissolve the bone so that he can now digest the marrow.
Others come looking for leftovers.
But their timing isn't ideal
because now the young lammergeier has his turn!
They'd better mind their heads!
Proficient bone smashing takes endless practice
to find just the right height, speed and moment of release.
Lammergeiers have long, broad wings,
ideal for gliding great distances with maximum efficiency.
But on the island of Little Tobago in the Caribbean
lives a bird for whom aerial agility is of paramount importance.
The red-billed tropicbird.
Short, pointed wings give it great manoeuvrability and speed.
During the breeding season, these flying skills are tested to the limit.
While one parent looks after the chick, the other must journey
far offshore, to gather small fish and squid from the surface waters.
But the hardest part is getting food back to the island, because they share this airspace with thieves.
Magnificent frigatebirds,
known as Man O' War birds, patrol high above.
These pirates are not trying to kill the tropicbird,
but force it to give up its catch.
It's an aerial dogfight.
Tropicbirds are quicker on the turn.
Frigates have exceptionally lightweight bodies
and their extremely long wings give them great power.
Success.
A favourite attack is from behind, and at height.
There goes the fish -
another victory.
This tropicbird chick still awaits the return of its parent
who has yet to run the gauntlet of the pirates.
Keeping close to the waves is his best chance.
Frigatebirds have so little oil in their feathers
they can't risk ditching.
If he can just reach the cliffs he'll be safe.
He's made it, with his crop still full of fish.
Red-billed tropicbirds rely on extreme aerial agility to overcome the many challenges of their life.
For others, survival demands endurance.
Every spring, red knots
fly 10,000 miles from their wintering grounds in Argentina to their nesting sites in Canada.
The only way they complete this marathon journey
is by making a crucial fuel stop here in Delaware Bay, on the east coast of America.
What is most extraordinary is that as well as having to find their way
to this one location, they must also time their arrival to perfection.
They have a rendezvous with prehistoric creatures emerging from the deep
which have hardly changed in 250 million years.
They come ashore in greatest numbers on the highest spring tides.
Horseshoe crabs.
The crabs are here to lay their eggs.
That's what the knots are after.
Most eggs are buried out of reach,
but some are accidentally dug up by other crabs.
Most of the west Atlantic red knot population join this feeding frenzy.
In a matter of weeks the knots need to rebuild their fat reserves
and double in weight.
To achieve this, each knot must eat as many as 400,000 eggs -
a tall order given the skill and effort needed to swallow just one.
Head down, feeding non-stop means it's hard to be alert to predators.
A peregrine falcon.
With egg laying complete, the horseshoe crabs now leave
these shores while the knots gather every last egg they can find.
It's time for the birds to move on.
The knots still have a further 2,000-mile non-stop flight
to reach their breeding grounds in Canada.
Flight gives birds many advantages, but there's a period in their lives
when they are forced back down to Earth.
The nesting season.
This is the time when they are at most risk,
so they must find the safest possible location.
Few go to greater extremes than lesser flamingos.
They nest in the remotest corners of Africa's caustic soda lakes.
Like their reptilian ancestors, birds lay waterproof eggs.
Despite this, flamingos still protect theirs
on special mud-stack nests as the lake is prone to flooding.
It's also just a little cooler up here.
Temperatures at ground level can reach a blistering 50 degrees Centigrade.
Once a chick hatches, it spends the first six days in the nest.
This is when it's at its most vulnerable -
totally reliant on its parents.
The caustic mud deters predators.
But the adult flamingos can cope in this quagmire, because of their long, scaly legs.
Any chick that slips from the nest, however,
is treading on very dangerous ground.
This parent encourages her chick to climb back to safety.
Raising chicks requires huge parental investment in both time and labour,
wherever you are.
Few places are tougher than the Antarctic.
Chinstrap penguins.
Every day they travel up to 50 miles out at sea, hunting for krill.
But the hard part is getting this food back to the colony,
because it sits on the ice-free rim at the top of this giant volcano, Deception Island.
For the returning fishing party, the first challenge is getting ashore.
The beach is steep, with a powerful undertow.
This female lands safely, but she now begins a long journey on foot.
For a flightless bird, getting to the top of the volcano
means a gruelling climb, especially when glaciers,
covered with muddy volcanic ash, stand in your way.
It's like a game of snakes and ladders.
A combination of beak, wing tip and feet.
And she wins through!
Now she joins penguin rush hour.
Almost home.
She's reached the crater rim, but her trials are still not over.
She must now try and find her family among more than a 150,000 birds.
Her hearing is so acute she can identify the individual cry of her own chick in the din.
She's made it and the family welcomes her return.
The result of all this parental effort - a mouthful of krill.
Now it's her partner's turn.
A chick's demands are endless.
Sometimes they can push parents to desperate lengths.
But birds are masters of improvisation.
Dassen Island, off the coast of South Africa, is home to a nesting colony of great white pelicans.
There are chicks of all ages all with a hefty appetite.
The parents have a formidable task.
These pelicans are among the heaviest flying birds in the world, weighing up to 10 kilos.
A V-formation is the most energy efficient means of flying.
It significantly reduces drag for the bird behind.
Pelicans normally fish along the coast,
but a shortage of food supplies has forced them to look elsewhere.
Cape gannets
plunge deep, hunting fish beyond the reach of the pelicans.
But the pelicans aren't after fish.
Their sights are set on a bigger catch.
Malgas Island is the nesting ground for some 60,000 Cape gannets.
Normally one gannet parent goes off fishing while the other looks after the chick.
But declining fish stocks means both parents are often away hunting at the same time,
leaving their chicks unguarded,
something which hasn't gone unnoticed by the pelicans.
Only chicks with parents at their side,
or those too large to swallow, have a chance.
Back at the pelican colony,
the parents regurgitate partially-digested gannet chicks
for their brood.
Although most seabird colonies on the African Cape are in decline,
the population of white pelicans nesting on Dassen is growing.
When birds come together to breed,
and before they commit to one another,
they will often perform the most remarkable displays.
One of the most enchanting happens here, on the lakes of Oregon.
Clarke's grebes mate for life, but the female must test her partner's continuing commitment,
and she does this by inviting him to join her in a ritualised dance.
To strengthen their bond, he offers her a gift.
Now, with eyes only for one another,
the faithful pair reach the climax of their dance.
Other birds don't form pairs.
Instead a male tries to mate with as many females as he can.
Male sage grouse gather in the grasslands of Wyoming
to advertise their virility
with a finery of feathers and proud posturing.
THEY MAKE POPPING SOUNDS
Females are much drabber-looking,
but extremely choosy.
They will only mate with the most impressive male,
and they judge a male's worthiness by the sounds he makes.
POPPING
Birds go to great lengths to impress their partners.
In the forests of New Guinea,
they famously use colourful feathers and song to maximum effect.
BIRDSONG
Birds of Paradise.
But in the western part of the island, these flamboyant birds
share the forests with a rather unassuming-looking character...
the Vogelkop bowerbird.
He might lack the plumage, but he's got an extraordinary repertoire of song.
And, he's a wonderful mimic.
HIGH-PITCHED SOUNDS
Those are pigeon wing beats.
HIGH-PITCHED CALL
That's a modest tiger-parrot.
LOWER-PITCHED CALL
And that, a sulphur-crested cockatoo.
Even more surprising he's an avid collector,
with a very appreciative eye for colour.
This male favours red and orange flowers.
And he's very fond of fungus.
Not everything he collects stays where it should.
He puts these treasures on display within and around a construction that has taken him years to build.
A giant bower woven around a central sapling, carpeted with moss.
This grand design is no nest...
it's the ultimate seduction parlour.
But he's not alone on this hillside.
He's got six rivals within earshot.
This one prefers darker colours, decorating his bower with deer dung.
And charcoal.
Visual effect is of crucial importance.
Clearly he hadn't planned on all this sprouting fungus.
He and his nearest rival live a stone's throw apart.
Competition is intense.
It's the dung-ball bower that is the first to catch the female's attention.
He withdraws, while she inspects his workmanship.
She's back again, and seems impressed.
But on closer inspection she is less convinced.
Perhaps it was that sprouting fungus!
Back at the flower bower, the male performs a dress rehearsal.
He senses she's watching.
This is the moment he's been working towards.
BIRD CALLS
His bower channels his song in her direction.
MALE CALLS
A final check.
All is to her liking.
Few birds devote such craft, effort and ingenuity to achieve this life-defining moment.
But here on Kenya's Lake Bogoria, these massive pink slicks
signal the start of perhaps the grandest courtship event in nature.
In certain years, when the lake is at its richest,
more than a million lesser flamingos congregate to feed.
It's now, when they're in their prime, that they must find their preferred partner.
To do that they perform a remarkable promenade.
With heads held high and neck feathers ruffled,
making them look as pink as possible,
more and more birds join in the courtship march
and pairs begin to bond.
Small groups merge with larger ones
until almost 1,000 flamingos are on the move.
From the equator to the poles,
birds have found the most ingenious ways
of overcoming the many challenges of life,
and everything revolves around their unique attribute, feathers.
For the past three years, the Life team has filmed birds in every part of the world imaginable.
Nowhere was the filming trickier than in the jungles of West Papua.
Here is found for me one of the greatest wonders
of the bird world, the display arena of the Vogelkop bowerbird.
13 years ago I was lucky enough to witness these spectacular builders,
but filming the timid female and courtship behaviour was a different matter.
And this was what the Life team set out to film.
Barrie Britton was the principle cameraman for this programme.
With over 20 years in the business,
not only is he an accomplished photographer
but he has developed a deep understanding of and empathy for his subjects.
Although each one posed it's own unique challenges,
Barrie he did seem to spend an inordinate amount of time cooped up in his trusty old hide.
Think I may have misjudged the hide position, cos the sea's coming in the bottom of the hide.
Well, that was 11 hours in my little box.
Barrie saved his most ambitious trip of the series until last.
It took a team of 40 people 3 days of tough uphill trekking to get to the filming camp.
I could complain about leeches, biting insects, the tough going
but, I really don't want to, this is great.
Seem to have lost everyone else, I hope I'm going the right way.
Oh, made it.
Completely shattered.
The hard work had only just begun.
Tomorrow with the help of their guides, the crew would go looking for the best bowers to film
but not before a cautionary tale from the local chief.
HE SPEAKS IN HIS OWN LANGUAGE
So when he first was shown the bower by his father
he, there were flowers there,
and, as a 12-year-old child he wanted to grab them
but his father immediately stopped him
and said, that he could not touch anything or take anything away from the bower
because otherwise it would start raining very heavily.
BEEPING
Oh! It's ten to five, Barrie.
Yep.
With the chief's warning fresh in their minds,
Barrie and the team make an early start and head for the hide.
Well, we've reached the hide just at sunrise, so we're just gonna get set up as quickly as we can.
With knowledgeable guides, finding the bowers wasn't the problem.
And who could miss such obvious structures?
It was now a waiting game for Barrie,
heavily concealed in his camouflaged hide.
OK, it's 6.30,
so I'm just waiting now for the bird to come, hoping that
he doesn't suspect that anything is here
and that we can get some natural behaviour.
BIRD CALLS
I've just heard the bowerbird call just to the right of the hide.
RUSTLING
I can hear the bird outside, it's plucking on the fabric of the hide.
I've just noticed that the bird has pulled a Snickers wrapper out
of the bottom of the hide and has added it to its display.
It was a very strange decoration
which I had to remove at the end of the day.
THUNDER
Had Barrie tempted fate by removing the wrapper and ignoring the chief's warning?
Or was this just rainforest living up to its name?
When it pours like this, filming becomes virtually impossible.
Soon the weather improved and Barrie returned once more to the hide.
This time his lunch box was firmly sealed.
The bird is very keen on these little tiny metallic ladybirds
and they're a bit put out being put there in this bower,
so, they start crawling off, they're very slowly making their way
over the moss and they just about get to the edge of display
and then the bowerbird notices and goes and collects them and puts them back again,
so they're kind of in this endless cycle of trying to escape from the bower,
they're just, they can never quite get away.
However for the male bowerbird and Barrie the female was still proving a problem.
The female did come down, but she was quite nervous
near the entrance to the bower, so we didn't get very much of that.
This was a real concern,
because the courtship behaviour was key to our story.
He's just done a 10-hour stint,
been a really nice day so we're just hoping it's gone well.
Another day's filming over, and still little to show for it.
10 hours in the hide.
Fortunately filming is over for the day,
we're just gonna go and collect Barrie again.
Did you see a mate today?
No, no, mating.
Everything else is going well but we haven't got the mating.
The fact I was getting such good footage of the male meant he'd obviously got used to the hide.
But the visiting females were still wary of it.
The females did seem a bit nervous, so I took the decision to push the hide back,
just to get more distance from the birds, the other thing I've done is recessed the lens
and we put this vegetation all around it, so I'm hoping that's gonna provide more female behaviour.
There were few filming days left, it was crucial Barrie's adjustments paid off.
The male has just run into the bower and started calling
so I think that means there might be a female coming.
It struck me, here we both were waiting in the darkness,
the male trying to attract the female,
and I was just hoping that I'd got it right this time and it was more than just a fleeting visit.
Working in a hide involves hours of prolonged inactivity
punctuated by the most intense moments of action.
This was the crucial moment the whole team had worked towards.
Everything was falling into place for Barrie,
the behaviour unfolding.
Right, that's good, think we're in action.
21 days in a hide,
astonishing patience and perseverance.
This has never been filmed before.
Such effort and endeavour for a crucial piece of behaviour that's over in a matter of seconds.
Would you like to shake my hand, Stephen?
What does that mean? Well, we got the mating.
You got the mating? Yeah, yeah, we got the mating.
Oh, wow. Yeah, so really good day, brilliant day, yeah but just, just amazing.
I must have - well, what is it - three weeks I've spent sitting in this hide, and I just didn't think
we'd ever get it, cos we're running out of days, only a few left now, so, so to get that this week is,
is just incredible and it was a really, really good, really good behaviour, so I'm delighted.
Success! This was Barrie's last filming trip for the Birds episode
and what a befitting end.
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