'A bird's life in Wales must be wonderful. A life made in heaven.
'Anything but.
'Birds have to work from dawn to dusk to find food and water.
'If they don't, they die.
'They have to battle with the elements too.
'Survival, especially during winter, is always difficult.
'And during the spring, they're busy raising families.
'They also have to put up with us
'and find a way of surviving in our artificial landscape.'
In this series, I'm going to be finding out what a bird's life is really like in Wales.
I'm going to be discovering the vast array of species we have here
and I'll be probing into their secret lives.
'These wood pigeons have nested in the centre of Cardiff.
'It took the pair a week to build the nest.
'The female laid the eggs.
'For three weeks, both the male and the female took turns with the incubation.
'The chicks hatched four days ago.
'All is going well.
'And then, disaster strikes.
'A female sparrowhawk locates the nest.
'The pigeon flees, unable to defend her chicks against such a powerful predator.
'The sparrowhawk kills the chicks and eats them.
'This is the harsh reality of life.
'In this programme, I'll be looking at how birds protect themselves from being killed and eaten
'and prevent themselves from starving and freezing to death.
'In this woodland on Anglesey, one bird has made a decision
'that may greatly reduce the chances of her chicks surviving.'
This is really odd.
It's obviously autumn, you've got leaves all over the floor,
the trees have all changed colour,
but come here and have a look at this.
Just in front of me here, at the base of this stump,
just down there, is a mallard sitting on eggs,
in the middle of October!
Mallards usually nest between late February and July, early August maybe,
so why is a mallard sitting down there now?
We've had a month of really mild, warm weather,
and I think that they're confused, they think it's spring,
so they've thought, "Oh, wow, let's mate, let's lay eggs."
And that's exactly what they've done.
She's just really well hidden at the base of that stump.
'With winter approaching, the chances of this mallard raising a family are slim.
'Even if her eggs hatch, as the weather gradually turns colder,
'survival will be extremely difficult for a young bird.
'And that's why most birds nest in the spring.
'Warmer temperatures mean there's a wealth of food available on land and in the sea.
'It's a season when everything comes to life.
'And for woodland birds especially,
'it coincides with a glut of caterpillars eating the leaves.
'And that's one of the reasons why migrant birds come to Wales in the spring.
'To ensure that their chicks have the best chance of survival,
'birds like the willow warbler travel north from Africa to a landscape that's rich in food.
'This upland farm is near Bala and a beautiful male redstart is feeding chicks.
'It too has come from Africa.
'Redstarts naturally nest in tree holes,
'but this pair have decided to use a hole in a barn wall instead.
'The female is less brightly coloured
'and shares the feeding responsibilities with the male.
'With lots of insect larvae, even here on the uplands during spring,
'their chicks have all the food they need to survive.
'Most of the small migrant birds that come to Wales for the summer are insect eaters.
'And it's a time of year when insects are plentiful.
'These swallows are feeding in the Brecon Beacons.
'Because our climate is damp and mild, swarms of small insects emerge
'and this is essential for the swallow's survival.
'And the insects keep flying, even on a bad summer's day.'
Birds are amazing things.
It's a really cold, miserable, wet, Welsh day
and yet, you've got half a dozen swallows, feeding above the water.
Even in weather like this, they have to feed
because they've got chicks back at the nest.
Usually you see them feeding high up above the trees
or up in the sky because on a warm day, that's where the insects are.
But now, it's cold and wet and the insects have been pushed down low,
so they're feeding above the surface of the water and along the banks.
They go along with their beaks open, like a hoover,
they're going to hoover up the insects
and they'll get dozens, sometimes even hundreds at a time,
then they'll go back and feed the chicks.
'These water pools are in Cwm Darran, near Merthyr Tydfil.
'Higher up on the heathland above the valley, meadow pipits are nesting.
'This pair have succeeded in raising good, healthy chicks.
'Other pipits may not fare as well.
'There's a cuckoo about
'and that could have a big effect on a pipit chick's survival.
'This female is patrolling the heath, on the lookout for a place to lay an egg.'
And this is what the cuckoo's been looking for.
It's hidden out of the way, beneath the bracken.
The cuckoo has been perching on the pylons, down there,
where she's got a good all round view of this area.
She's waiting for the pipit to leave its nest, she'll then dash in,
lay an egg in there and the cuckoos that target meadow pipits
make their eggs look like meadow pipit eggs.
That egg will then hatch, the chick will throw out all the other eggs,
so that the adult meadow pipit will just feed that one chick.
'Meadow pipits will do all they can to make it difficult for the cuckoo.
'Once it's detected, it will be mobbed ceaselessly.
'Not so much that it's a cuckoo but because it generally looks like a bird of prey
'that could kill its chicks.
'The pipit will also try and conceal its approach to the nest,
'but inevitably, the cuckoo will succeed.
'It'll manage to lay an egg in a nest.
'Her egg on the left is only slightly different.
'While the others have a dark patch on one end,
'the cuckoo egg doesn't.
'Less than two weeks later, a very bold cuckoo chick hatches.
'It has special claws at the tip of its immature wings
'to enable it to grab the side of the nest to eject the other eggs.
'This, it'll do eventually and the parental urge will be so strong
'that the meadow pipit parents will continue to feed the cuckoo chick,
'even though it'll be the only chick left and look different to their own
'It's cruel for the meadow pipit, but essential for the cuckoo.
'Hiding the nest from predators is a crucial part of survival.
'Birds have different ways of doing this.
'Hidden in bushes,
'inside trees,
'on inaccessible cliffs,
'underground,
'in and around buildings.
'While curlew are often seen on estuaries in the winter,
'they nest inland on the ground.
'And one curlew has chosen a field near Newtown.'
It's a typical place for a curlew nest, but not really a typical nest
because usually, they lay three or four eggs.
There's only one here. What's happened? I don't know.
It's difficult to tell. It may well be that a stoat or a fox has had the other eggs,
or it may well be that she nested elsewhere, failed, and she's had time to lay just one more egg.
It's a typical situation because they love these grass fields.
It's a big bird, so they need tall cover, she'll be tucked down here
on the eggs and even when she has to fly off, it's well camouflaged.
And bear in mind, usually, the grass is over like that,
so from the air, you're going to see absolutely nothing.
I'd better leave her, I think.
'It's tough being a curlew in Wales.
'There are few nesting pairs
'as there are not enough suitable habitats for them.
'Much of the Welsh landscape is bare ground
'and predators, like crows and buzzards, soon find the eggs and chicks.
'Some birds don't have a nest to hide. They simply hide themselves with excellent camouflage.
'This chick has been left by its parents on bare ground above Resolven, in the Neath Valley.'
If you're a bird that's decided to nest on the floor,
then you've got to be really well camouflaged and your chicks have got to be really well camouflaged too.
There's not a single bird in Britain that does that better than the nightjar.
Just a few centimetres in front of me is a nightjar chick.
It's nearly 9:00pm and the parents have gone off to hunt
and they've left their chick behind, on the floor like this,
completely confident that it's so well camouflaged
it will never be found by any passing fox or badger,
or any predator at all.
And to find a chick like that in an area like this
is almost impossible.
'Not daring to give itself away, the chick is always very still,
'even at night, but when the parents return from hunting,
'remaining hidden takes second place to getting dinner.
'The chick is being fed insects, probably moths.
'This is Traeth Lafan in the Menai Straits, on the north Wales coast.
'It's one of the best locations in Wales to see wading birds.
'While feeding in such an open, exposed location,
'birds need to protect themselves from being killed by predators.
'And the most effective method of doing this on an open estuary
'is by keeping together in a flock.
'This is even more important at high tide,
'when the feeding stops and the birds gather together to rest.'
There must be over 1,000 oyster catchers,
all packing into the end of this spit here.
It's high tide, so the water's driven them off Traeth Lafan,
onto the last little bit of safety, this linear bit of land.
And there's a big advantage to this.
This area is regularly hunted by peregrines.
Peregrines will take oyster catchers.
If you're one bird in amongst 1,000 over there,
it's much safer than being one on its own, right out here.
'The telltale sign that a peregrine is about
'is the sight of flocks turning and twisting to evade capture.
'This is a male. It has landed to survey the scene.
'A female, probably his partner, is also on the hunt.
'The problem for a peregrine, in such an open area,
'is that it will always be immediately seen by the target birds
'But he has speed and a strategy.
'He swoops low to make the birds scatter.
'In the confusion, one might be caught.
'Being the fastest living creature
'with a dive that can reach a speed of 120mph,
'that strategy usually works.
'But not always.
'One essential part of survival is personal hygiene.
'Birds constantly preen.
'They do this to keep their feathers in good condition.
'If they're damaged, they can't fly and they can't escape from predators
'or find food.
'They also won't be able to fluff out their feathers to keep warm during cold weather.
'They meticulously work on each feather,
'making sure that all the intricate parts are in the correct place.
'Most birds have an oil gland beneath the tail
'and use the bill to spread the oil over the feathers.
'This maintains flexibility of the wings
'and makes the whole body waterproof.
'For water birds such as the mallard, this is essential.
'And in the summer, they'll have a good dip, just to keep cool.
'During August and September,
'the migrants that have spent the summer in Wales leave in search of warmer winter weather in Africa.
'Many are insect eaters and the supply of insects will soon dwindle in Wales.
'To survive, they must go south to find food.
'But some migrants arrive in Wales during the autumn.
'They come here to escape the cold weather developing further north.
'These are whooper swans
'and they've flown all the way from Iceland to a field near Porthmadog.
'Whooper swans feed on vegetation
'and that, in the sub-Arctic, will be covered in ice and snow.
'Here in Wales, grass will be available throughout the winter.
'On a beach at Rhyl, another migrant bird has travelled even further to be in Wales.
'These small birds have come from deep inside the Arctic Circle.'
These are snow buntings, smashing little birds.
And we tend to associate them with the Arctic
or the tops of the Cairngorms, and that's where they breed,
but in winter, they move down to lower ground.
One of their regular haunts is this beach in North Wales.
So why come here? It's not the most scenic beach in the world.
But the reason is, seeds. They're seed eaters, like all buntings.
Seeds blown by the wind get caught up on the pebbles on the beach
and amongst this vegetation, this marram grass here.
It's ideal for them and because the beach is long enough,
if they exhaust the supply in small areas, all they have to do
is move along a little bit and then move along again.
There is enough food here to last them all winter.
'It's amazing to think that this small flock of birds
'has travelled so far to be on this beach.
'As long as there's food for them here, they'll continue to do so for generations to come.
'Migrants also come to Wales from mainland Europe during winter
'to escape the colder continental climate.
'Fieldfares and redwings migrate from Scandinavia.
'Thousands of starlings arrive from all parts of Europe.
'And they all arrive during a time of plenty - the autumn harvest.
'These are eating hawthorn berries.
'One migrant is particularly stunning.
'These are waxwings and they've arrived at Towyn in North Wales.
'Waxwings usually end up on our shores
'only when there's a poor berry crop
'on their own home patch of Scandinavia.
'To survive, they keep on moving west until they find a decent crop.
'The local birds who stay here all year round
'have to compete with the winter migrants for berries.
'It's a case of eating as much as they can while it lasts.
'But the berries soon run out.
'Then, they literally have to scrape and dig to survive.
'Every leaf turned for any grub or a worm.
'And as long as the ground remains soft for most of the winter, they get by.
'But if the weather turns colder, life gets tougher.
'These are the Brecon Beacons in mid winter.
'It's a particularly cold period.
'All food sources have been covered with snow and ice.'
I love weather like this. Everywhere is just completely white.
But it's not so good for birds
because with snow covering the fields, there's no food for them.
Behind me however, is a field full of oats
and that is a magnet for dozens of small birds.
'That one small field can be the difference between life and death for them.
'These birds are lucky.
'The field has been set aside for feeding birds at Slwch Farm, Brecon.
'The cereal seeds have been left for their benefit.
'And they're all here.
'Finches.
'A yellow hammer.
'And reed buntings.
'And also brambling.
'They're one of the migrants that come to Wales
'in pursuit of a warmer winter, but not today.
'And they're not the only hungry birds around.
'Winter is a difficult time for sparrowhawks too.
'And with so many of its favourite prey attracted to this one spot,
'it doesn't take it long to find them.
'Attacking quickly, it hugs the hedgerow, trying to chase down its prey.
'All the small birds can do is take cover or stay still in the crop.
'They're so hungry,
'they must resume eating as soon as it's safe to do so.
'It's a choice of starving to death or being eaten.
'Big birds also have problems finding food during winter.
'Most of them survive by having a varied diet.
'When we think of buzzards,
'we imagine a powerful bird of prey that kills to eat.
'And sometimes, it will take rabbits, small birds and chicks.
'But it also eats worms.
'You often see many buzzards in a field digging for a meal.
'These are on farmland near Trecastle in the Brecon Beacons.
'It's believed that buzzards are common in Wales
'because there's so much worm-rich pasture available for them.
'Buzzards are also scavengers
'and during a cold spell when the ground is hard,
'they'll search the landscape for dead animals.
'This one has found a carcass on the uplands near Dolgellau.
'It's already been opened by ravens.
'Because of its small beak,
'a buzzard finds it difficult to open a carcass.
'It's dependent on a raven to do that.
'It has the perfect tearing beak.
'Once opened, the buzzard can then easily pick up the exposed tissue.
'The estuaries of Wales are renowned for their wintering birds,
'with thousands flocking here from the frozen Arctic
'and parts of Europe to find food.
'This is the Mawddach Estuary near Dolgellau.
'Occasionally, our winters are so severe,
'that the estuaries become as inhospitable
'as the places the birds have migrated from.'
I've never seen the Mawddach Estuary look like this before.
It's all iced up, and because we've had a succession of mild winters,
I think we tend to forget that every now and again,
when we do have a very hard winter, even our estuaries freeze up.
And that is very bad news for hundreds of thousands of birds that escape the cold
of the Russian Arctic, the Far East, just to come here.
So it's going to be extremely hard for them.
To be honest, it looks more like the Arctic here.
'During another cold snap, the Conwy Estuary is frozen.
'Although the Welsh landscape may look beautiful on a cold winter's day,
'they are a wasteland in terms of food for the birds.
'For curlew who need to probe deep into the mud for food,
'this becomes an impossible task if the ground is frozen solid.
'Fortunately, the unfrozen small river channels
'act like arteries of life through the arctic landscape.
'Here, many birds can feed as normal,
'using their beaks to spear the small morsels buried in the mud.
'These are the most challenging conditions for survival.
'During a severe winter, many birds will die,
'especially further inland.
'That's why it's important that we give them a little help when the going gets tough.
'In return, birds that are familiar with people give a great show.
'And in the next programme,
'I'll be looking at the different ways birds have adapted to us.
'How they make use of the landscapes we've created,
'the structures we've built, and the materials we discard.'
Subtitles by Red Bee Media Ltd
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