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02:20These shallow, gravelly streams here in the New Zealand Alps
02:25seem desolate places devoid of any food.
02:29But look at the underside of this pebble I've just picked up,
02:32several succulent insect larvae.
02:35And, in fact, these streams,
02:37like waters fresh or salt all over the world,
02:40are full of food.
02:42And when you consider that two-thirds of the world
02:45is covered with water, that's a huge resource.
02:48No group of animals living out of water
02:51have developed a wider range of techniques
02:54and, indeed, tools for collecting that food than the birds.
03:00This one is unique,
03:02the only beak in the entire bird world that is bent to one side.
03:06This is the rye bill, which only lives here in New Zealand.
03:11Its extraordinary beak enables it to probe beneath large, heavy boulders
03:16that it couldn't possibly turn over or even shift.
03:32And, just in case you're wondering,
03:34the bend is always there,
03:37and, just in case you're wondering,
03:39the bend is always to the right.
03:48Dippers plunge right into the streams.
03:58This one is in Yellowstone in the American West,
04:01where hot volcanic springs keep the streams clear of ice in winter
04:05so that the dippers can walk underwater throughout the year.
04:13Their dense, oily plumage retains air to such a degree
04:17that it forms a silvery cloak around their body
04:20and so keeps the birds warm.
04:23The disadvantage of that coat of air
04:26is that it makes its wearer very buoyant
04:29and the dipper has to struggle hard to remain below the surface.
04:34They seldom manage to stay underwater
04:36for much more than a quarter of a minute at a time.
04:42It's not uncommon for a bird to enter a dipper
04:45and stay underwater for a whole hour.
04:50But this one has been in the water for more than a year.
04:55When it enters the dipper,
04:57it only holds its breath for about a minute
05:00for much more than a quarter of a minute at a time.
05:25Kingfishers are only underwater for a second or so.
05:29They're living harpoons.
05:31This is one of the bigger members of the family, the belted kingfisher.
05:35It's the size of a small crow
05:37and lives beside rivers and lakes all over North America.
05:42Understandably, it prefers places where the water is clear
05:46so that it can get a good view of its targets.
06:00Having caught a fish, it must now stun it
06:03and to do that, the fish has to be head outwards.
06:12But if the kingfisher is to swallow it
06:14without the spiny fin sticking in its throat,
06:16it has to turn the fish round again.
06:19Most kingfishers dive from perches
06:22and that means that they're more or less tied to the shore.
06:25Only one of them is able to break that link.
06:29This is the African kingfisher.
06:31It's the largest kingfisher in the world.
06:34It's about three metres long and it's got a long neck.
06:37It's got a long tail and it's got a long tail.
06:40It's got a long tail and it's got a long neck.
06:43It's got a long tail and it's got a long neck.
06:46This is the African pied kingfisher
06:49and it can launch its dive from high in the sky
06:52because even in completely still air, it can hover.
06:56It's the biggest bird in the world to be able to do this.
07:17It's not only a diver, sometimes it's a juggler.
07:31The darter does its harpooning underwater.
07:34It's so at home there that it can actually creep up on its prey.
07:39It's a very good diver.
07:41It's so at home there that it can actually creep up on its prey.
07:49Mist.
08:06It always has to juggle to get its catch off its harpoon.
08:11Mist.
08:24The darter doesn't have the dipper's problem with buoyancy
08:27because its feathers actually absorb water.
08:33But that means that it gets soaked to the skin
08:37and after a swim, like anyone in a wet bathing costume,
08:40it has to dry itself quickly and thoroughly if it's not to get a chill.
08:57Some fish are incurably inquisitive.
09:02The little egret can attract them by doing no more than waggle its yellow feet.
09:11Mist.
09:17It seems a simple enough trick, but it works nonetheless.
09:24Birds all over the world have devised all kinds of bizarre solutions
09:29to the problem of extracting little fish from shallow pools.
09:33In the swamps of Florida,
09:35the reddish egret performs an improbable kind of dance.
09:41Mist.
09:45The idea seems to be to frighten the little fish out of their hiding places.
10:11Mist.
10:15Shading your eyes can help you see what's down there beneath the reflections.
10:24And there was something.
10:31In Africa, the black heron takes the business of shading its eyes
10:35very seriously indeed.
10:41Mist.
10:51Maybe cutting out reflections is not the only reason for doing this.
10:56Many fish prefer to swim beneath an overhanging bank or a tree
11:00so that they can't be easily seen from above.
11:03So perhaps they deliberately take shelter under the heron's wings,
11:07which, of course, could be a mistake.
11:10Mist.
11:41The spoonbill isn't really after fish.
11:44This scything action of its beak
11:46enables it to gather tadpoles, beetles and insect larvae,
11:50but it must also scare little fish, which then dash off to seek safety.
11:55So it's worthwhile for the black heron to follow the spoonbill around,
11:59just in case.
12:11Mist.
12:21The pygmy cormorant certainly is after fish
12:25and therefore thinks it's a good idea to follow the heron.
12:28Maybe the heron is having better luck.
12:41All in all, a little fish doesn't stand much of a chance
12:45in a shallow pool like this.
12:49These two are fishermen, but they don't wade, they skim.
12:54And to do that, they need not long legs, but a long beak.
13:00Or, to be more accurate, a long lower mandible.
13:04The upper one is more or less normal in size.
13:07This is the skimmer, a highly specialised relation of the gulls.
13:20Their chicks, in fact, look very like gull chicks.
13:28They don't develop that extraordinary beak
13:30until they are some three months old.
13:38Skimming, although it demands flying of the greatest precision,
13:42is straightforward enough in principle.
13:45As soon as the lower mandible ploughing through the surface of the water
13:48touches anything solid, a reflex action will make it snap shut.
13:54That sounds fine, but supposing the beak hits something really big,
13:59like a floating twig, or worse, a submerged rock, what then?
14:04Well, the fact is that quite a lot of skimmers have broken mandibles.
14:08Whatever the hazards, overall, the technique is a very successful one.
14:14The chicks have to be fed from the bottom up,
14:17and that's where the technique comes into play.
14:22What's the best way to keep the chicks from swimming away?
14:26You can't keep them in the water for too long.
14:30They can't stay in the water for too long.
14:33is a very successful one.
14:37The chicks have to be fed for six weeks,
14:39and skimmers are faithful and hard-working parents,
14:43bringing food every ten minutes or so for hours on end
14:46when the fishing is good.
14:52But while they're certainly devoted to their young,
14:55they are sometimes just a little optimistic.
15:03CHICKS SQUAWK
15:28Oh, well, if baby doesn't want it.
15:33CHICKS SQUAWK
15:37Skimmers and egrets and kingfishers live beside the water.
15:41Some birds live actually on it.
15:44Mallards must be one of the most familiar birds in the world.
15:49And because of that, perhaps we tend to take ducks for granted.
15:52But in fact, they're a very varied family.
15:55Different species are adapted to different ways of life on water.
16:00Mallard, for example, are specialist dabblers.
16:04CHICKS SQUAWK
16:06They find all the food they need by doing no more
16:09than dipping their heads and necks beneath the surface.
16:12And there's lots of food to be found that way.
16:15Duckweed and tadpoles, leaves and seeds,
16:19and bits of bread thrown in by friendly humans.
16:22CHICKS SQUAWK
16:33CHICKS SQUAWK
16:43If the food they've spotted is really deep down,
16:46they will upend totally.
16:48If that doesn't get it, then it's beyond their reach and that's that.
16:53CHICKS SQUAWK
16:56Ducks keep their plumage water-resistant
16:59by anointing it with oil from a gland on their rump.
17:03They also keep their feathers clean and soft and pliant
17:07by frequent and enthusiastic bathing.
17:09CHICKS SQUAWK
17:17Ducks don't all just dabble.
17:20Some dive deeper.
17:23The maganza has webbed feet like the mallard and all other ducks,
17:27but they're placed very far back on the body.
17:30That's the best place to have a propeller from a mechanical point of view,
17:34and as a result, they can swim quite fast enough to catch small fish.
17:38CHICKS SQUAWK
17:44Their bills are notched like a fine saw,
17:47which helps when you have to grapple with a slippery fish.
17:50CHICKS SQUAWK
17:52DUCKS SQUAWK
17:57The young start diving almost as soon as they're hatched,
18:00but they're still covered in garm,
18:02and that makes swimming underwater very difficult indeed,
18:05and they use up far more energy than their streamlined parents do.
18:09DUCKS SQUAWK
18:22CHICKS SQUAWK
18:43The most skilful underwater swimmer of all freshwater birds, however,
18:48is the diver.
18:49This is an immature one
18:51that has not yet got its spectacular black-and-white plumage.
18:55Its feet are placed so far back on its body
18:58that out of water it can hardly walk,
19:00but underwater it's superbly manoeuvrable.
19:04Small fish have little chance.
19:13Diver chicks, when they first hatch, are covered with garm.
19:17That's very useful for keeping warm.
19:19It can be very windy out there on the lake,
19:22but as the mergansers demonstrated, it causes problems when diving,
19:26and young divers don't even try.
19:31Diver chicks, it has to be said, are rather pampered.
19:35They're regularly given lifts,
19:37and while one of their parents ferries them around,
19:40the other goes to find food for them.
19:48The male finds a fish, but decides to eat that himself.
19:57He's been away a long time and the family is getting hungry.
20:07But now he's found a crayfish. That will do for them.
20:18The crayfish is carefully broken up
20:20and passed over to the chicks a little piece at a time,
20:24with great delicacy and quite a lot of patience.
20:48Lakes have a tendency to shrink.
20:51They get shallower as rivers dump sediment in them,
20:54and in the tropics, they may even dry up every year.
20:58As a result, all sorts of delicious things come within reach,
21:02as they have in this African pool.
21:07The open-billed stork has a special liking for mussels
21:10and a special way of opening them.
21:12First, a sharp squeeze to make the shell open slightly.
21:17Then the lower mandible is slipped in to cut the body away from the shell.
21:28After that, it's easy.
21:40Snails require a slightly different treatment.
21:44To start with, they have to be taken onto solid ground.
21:50Now the little disc with which the snail can seal its shell has to be removed,
21:55and that's done by delicately squeezing it in just the right place.
22:06There.
22:08Then, once again, the muscle that attaches the snail to its shell
22:12has got to be severed.
22:14And out it comes.
22:29As the dry season progresses, yellow-billed storks
22:33As the dry season progresses, yellow-billed storks
22:37travel in flocks from one drying riverbed to another.
22:42When the water started to shallow, many of the fish retreated to the main river.
22:47Those that didn't are now trapped and doomed.
22:54The yellow-billeds have a labour-saving technique for fishing
22:57in these overcrowded pools.
22:59They just hold their beaks open and wait for the fish to blunder into them.
23:12Only one kind of fish is likely to survive the coming drought.
23:17The lungfish will soon cocoon itself in the mud at the bottom
23:21and remain there, dormant, but still alive,
23:24even when the riverbed is bone dry, because it can breathe air.
23:40But before it cocoons, it has to survive another peril.
23:45The shoe-billed stork has a massive and murderous beak.
23:57It also has keen eyes.
24:07And infinite patience.
24:15BIRDS CHIRP
24:18MUSIC
24:43One bite crushes the lungfish's skull.
24:48MUSIC
24:57But it still wriggles and takes quite a bit of swallowing.
25:02BIRDS CHIRP
25:06BIRDS CHIRP
25:28On the margins of the land,
25:30the water retreats not just once a year, but twice every day.
25:35That exposes a completely different menu,
25:38and birds compete in order to be the first to collect it.
25:42Here in California,
25:44there are some that take almost suicidal risks in order to do so.
25:50THUNDER RUMBLES
25:59The surf bird is the clear winner.
26:02No bird gets to an edible morsel cast up by the waves quicker than it does.
26:12THUNDER RUMBLES
26:19It has split-second judgment.
26:43It may also be that it gets so close to the waves
26:46because that gives it the chance of catching a barnacle or a mussel
26:50before it has fully reacted to its exposure to the air and closed its shell.
26:57THUNDER RUMBLES
27:16THUNDER RUMBLES
27:34Where the coast is less rocky and the beaches are sandier,
27:37the waves are less violent.
27:40Here, birds of several different kinds will assemble,
27:43but they're not always in competition.
27:45Each collects from a particular place with a particular kind of implant.
27:50The godwits have long beaks with which to probe deeply into the sand
27:54for worms, crustaceans and little mollusks.
28:01Dowitchers with shorter beaks collect much the same sort of thing,
28:05but from nearer the surface.
28:16BIRDS CHIRP
28:22Sanderlings pick up bits and pieces that have just been washed ashore.
28:34Out in the shallow water,
28:36avocets are after shrimps and other swimming creatures
28:40that don't allow themselves to get stranded on the beach.
28:45The avocet holds its bill with the curved section just slightly parted,
28:50and as it sweeps it through the water and the mud,
28:52small invertebrates are carried into it.
28:55And the bill is so sensitive
28:57that the avocet can feel when something good has arrived
29:00and can quickly swallow it.
29:06Fish also come into the coastal shallows seeking the same sort of thing.
29:12And when they do, they become the target of pelicans.
29:21With a bill the size of a pelican's, you don't have to have pinpoint accuracy.
29:30It does help, however, for pelicans to feed in groups,
29:34for then fish fleeing from one lunging bill may blunder into another.
29:42The brown pelican also dives.
29:49But rather clumsily.
29:51It's so big and buoyant that it only goes a few feet down.
29:56It's very often accompanied by noddy turns.
29:59They know that the pelican will have to open its bill
30:02and get rid of all that water
30:04before it can swallow any fish it might have caught.
30:07And when it does, they might get a chance to steal part of its catch.
30:12So now it's a question of who loses patience first.
30:42The pelican cautiously opens its bill just slightly
30:46and the water begins to seep from its pouch.
31:12Done it this time.
31:22Boobies live on the coast,
31:24but their fishing grounds are way out in the open ocean.
31:29Every morning they leave their roosts
31:31and set off in small parties to scar the surface of the sea.
31:36They're searching for a pale greenish patch in the blue of the ocean
31:40that betrays the presence of a dense shoal of fish.
31:46The fish have been driven to the surface by a shark
31:49that is still lunging into the shoal.
31:58And now they are subject to an aerial attack.
32:02And now they are subject to an aerial bombardment.
32:27As the boobies dive, they draw their wings half back
32:30so that they can still aim
32:32and only fully retract them just before they hit the water.
33:01Sharks! Sharks! Sharks!
33:13Sharks! Sharks! Sharks!
33:19The bombardment will continue
33:21until either the shoal manages to escape downwards
33:24or the fading light of evening
33:26forces the boobies to return to their roost on the coast.
33:31Sharks! Sharks! Sharks!
33:39Boobies don't actively swim underwater,
33:43but members of the orc family, such as these guillemots and puffins, do.
33:54They propel themselves not with their feet like ducks,
33:58but with their wings.
33:59And they've paid a considerable price to be able to do so.
34:03The wings of a booby or a gull are far too long
34:06and insufficiently robust to be beaten underwater.
34:10So orcs have had to evolve shorter, stubbier wings.
34:14That gives them a rather clumsy whirring flight in the air,
34:18but it does enable them to fly underwater so well
34:22that they can outpace small fish.
34:29One family of birds has taken this development even farther,
34:34and one of them lives here in the Galapagos.
34:39We tend to think of penguins as sitting around on ice floes
34:44in the freezing waters of the Antarctic,
34:47so maybe these little penguins are the ones
34:50that are going to be the ones that are going to be the ones
34:53that are going to be the ones that are going to be the ones
34:56And maybe these little penguins,
34:58sitting right on the equator, seem oddly.
35:01But in fact these little ones are probably much more like
35:05the original ancestral penguins than their giant Antarctic cousins.
35:09Because those first ancestral penguins
35:12certainly flew as well as dive, as guineamogs do today.
35:16And if you were much bigger than this
35:18and had a wing shaped like a flipper,
35:21which is what all penguins use to swim,
35:23you would never get into the air.
35:25So, maybe these little ones are more like the first of the penguins.
35:30Penguins underwater look somewhat like dolphins and, indeed, the two families have similar
36:00evolutionary histories.
36:03Dolphins are descended from air-breathing land animals just as penguins are descended
36:08from air-breathing flying animals.
36:10Both subsequently took to swimming for their food.
36:14They became beautifully adapted and streamlined and now both are superlative swimmers and
36:20highly accomplished fishermen.
36:47Even members of the penguin family can dive for five or six minutes without taking breath
36:53and descend to depths of a thousand feet in search of food.
37:00Indeed, the only thing that limits penguins as swimmers is their need to breathe air.
37:13There is, however, one link that still ties them and, indeed, all birds to the land.
37:19They all have to return there in order to lay their eggs.
37:23For seabirds, the ideal place to do that is a remote island which has very few or preferably
37:29no land-living predators.
37:48Nobody knows why it happens, but when you make strange noises here, seabirds fall from
37:55the sky.
37:56I'm on Lord Howe Island, a tiny speck of land 300 miles off the east coast of Australia.
38:03Human beings only got here a little over 200 years ago and it seems that the birds that
38:08nest here are still quite curious to see what's going on.
38:12And these birds, which are coming to these calls, are providence petrels.
38:31Skilled in the air they may be, but they're certainly clumsy and ungainly on land.
38:39But when they do come down, they squabble and wrestle furiously with one another.
38:43Perhaps they're arguing about who should have which patch for a nest hole.
38:52But they are still extraordinarily friendly towards human beings.
39:02And amazingly, and very touchingly, it'll stay here on my hand in a very trusting way.
39:09And it gives me a chance to look at this structure at the base of his beak.
39:16He has a tube nose and that structure, which he shares with a number of other ocean-going
39:24birds, is absolutely crucial to their survival out on the open ocean.
39:31And that is where he's going to go right now.
39:53That tube channels air to a sense organ at the base of the beak, which can detect very
39:58faint odours.
40:00It's a rare ability among birds and it enables the tube noses to find floating food from
40:06great distances away.
40:24I'm at sea, 20 miles out from the east coast of Australia.
40:30And in this bucket, I've got a particularly attractive liquid.
40:36It's fish oil.
40:37It's very nutritious.
40:39Being oil, it'll float on the surface of the sea.
40:43And above all, it smells very powerfully.
40:46And at the moment, there's not a bird in sight.
40:50But watch what happens when I put it overboard.
41:17The first to arrive are Sooty Shearwaters and Cape Petrels, closely related to those
41:23Providence Petrels on Lord Howe Island.
41:36It's not only the smell of fish oil and offal to which they're sensitive.
41:40It's recently been discovered that when small shrimps and other floating creatures feed
41:45on floating plants, algae, those plants release a gas that in strong concentrations smells
41:51a little like rotting seaweed.
41:53The Petrels can sense even the faintest whiff of this and so can find places where they
41:59can collect the shrimps.
42:03Now very much bigger ocean-going birds arrive.
42:24These magnificent birds are Owl-Petrosophis.
42:44They too are members of the tube-nose family, but the tube on their beaks is comparatively
42:49small.
42:50And in fact, they find their food more by sight than by smell.
42:55But they have enormous wingspans.
42:57Two of them, the Royal Albatross and the Wandering Albatross, have the biggest wingspan of any
43:03living bird.
43:04And they circle the globe in search of food.
43:11This is a Yellow-Nosed Albatross.
43:14It's not quite as big as a Wanderer, but it's still a very large bird with a seven-foot
43:19wingspan.
43:22No birds exploit the ocean winds with greater skill than the Albatrosses.
43:27Reading its force with peerless sensitivity, they're able to adjust their immense wings
43:32to exploit every tiny updraft deflected from the waves beneath.
43:37And so they can glide for long periods without expending any energy at all on flapping.
43:44The Wandering Albatross rides the violent gales of the Southern Ocean and will travel
43:49a thousand miles to bring back a crop full of food for its chick.
44:12The chick takes nearly ten months to grow strong enough for an ocean-going life.
44:18So although the Albatross, when young, may roam the oceans for several years without
44:22touching land, eventually the need to breed brings it down to earth.
44:29One bird has managed to break this long obligation to return repeated litter land to feed its
44:37chick.
44:39It's called the Ancient Murrelet and it doesn't feed its chick on land at all.
44:46The only place it nests are on islands around the northern rim of the Pacific, like Canada's
44:52Queen Charlotte Islands, where I am now.
44:55And the only time you're likely to see it is at night.
45:01This is one of their nest holes.
45:04The chicks, when they're only two days old, make one of the most astonishing journeys
45:09made by any chicks.
45:16The parents come back from the sea at night and, crouching on the ground, call to their
45:21newly hatched young.
45:26In response, the chicks come out of their holes running.
45:29There are large aggressive mice that will catch them if they get the chance.
45:33Ravens and eagles are also active during these light nights.
45:37The chicks are in real danger, so they run and run fast.
45:46Their parents have gone ahead of them and are now calling from the sea.
45:59By midnight, there are young chicks swarming all over the forest floor.
46:19Most of them manage to get to the beach within ten minutes of leaving their holes.
46:26But their parents are not here.
46:31They've gone farther out, just beyond the breakers, and they're still calling.
46:44The chicks don't stop.
46:46They keep pedalling like little clockwork toys, and the same movements that propelled
46:50them across the ground now take them out to sea.
47:01In some miraculous way, each chick recognises the sound of its parents' voice.
47:19United, the little families leave the land and its dangers and sail away into the relative
47:25safety of the open ocean.
47:27The chicks are still only a few hours old.
47:31The ancient Murrellet must be the most truly oceanic of all birds.
47:45Gone, and there's not a single one of those little chicks to be seen.
47:49By now, they're all at least four miles out to sea, called there by their parents.
47:57Sound of course is very important in the life of all birds.
48:00It's the way they communicate.
48:03And what they say, and the various ways in which they say it, is what we'll be looking
48:08at in the next programme, about the life of birds.