I. Akimushkin. Other rail birds. Cranes. From Gilgamesh to our days. Passenger pigeons. "Dead as a Dodo". Birds without nests. Lillipute birds. Kingfishers. Hoopoes and hornbills. Why does the toucan need such a beak? The woodpecker finch. Bowerbirds
The mesids number three species of birds of Madagascar. Their Russian name is even less appropriate since they are not gamebirds, and possibly are not rallids either. They are thrush-sized, or are slightly larger, short-winged and long-tailed, apparently flightless. Two species live in wood-lands, the third, the subdesert mesite, in dry scrubland in the southwest corner of the island. The subdesert mesite's beak is long, slightly bent to the bottom. Males incubate eggs and hatch the chicks. The nest in the shrubs is at height of 1-2 m. They get into it by climbing the branches. Usually there is a single egg. The chick leaves the nest quickly.
The limpkin is a single species. It lives in south of North, in Central and South Americas. They are slightly similar to the curlew and are about just as big, brown with light mottles, birds. They inhabit open country and swamps. They feed mainly on mollusks. They nest on the ground, more rarely on trees, the 4 to 8 eggs are incubated by both parents. The chicks leave the nest quickly.
The buttonquails, 15-17 species, live in southern Spain, in south Asia, Australia, on some Polynesian islands, in Africa, on Madagascar. They are found in the Ussuri on the territory of the former USSR.
They are small, quail-like birds. They are bad fliers, fast runners in grasses and among shrubs. Most species have only three toes on each foot. The males are smaller than the females are; they incubate the eggs and raise the chicks. The females only make nests in small holes, lay eggs, lek and fight each other over the males. In some species, they help to incubate eggs as well. The chicks hatch very quickly, after 10-13 days. The hatchlings grow up fast too: in 10-19 days they can fly, at the same age, or after another 2-3 weeks they become independent, in 4 to 5 months they are sexually mature. The newborns weigh only 2 g, a record of light weight among such birds.
The single species of the sunbittern lives in Central and South America. These are smallish, about the size of a jackdaw, birds with a beautiful 'mottled' coat. They are somewhat similar to herons, but their tail is too long and legs - too short. They may have the sun in their name, but they live in the shadows of dense rainforests, near to water. The nests are spherical, made from branches and clay, located on the ground, on shrubs and trees. Both parents incubate a pair of eggs. The chicks spend three weeks in the nest. The parents feed them as the water rails do, bringing them food in beaks. When threatening, the sunbitterns spread their wings and tail, becoming blindingly beautiful! Maybe this is why they have the sun in their name, and in another version, they have it because they lek in sunny clearings.
The finfoots number three species. One each in Africa, in Southeast Asia (from eastern India to the Wallace line), and in the New World (Central and South Americas). These are robust birds, the size of a crow or bigger. The toes are fringed with large flaps of skin. The sungrebe, (the American species) has toes marked with bright black and yellow horizontal stripes! They are good swimmers, (after emerging only the head above water), dive 'suddenly, without splashes', as the anhingas do. They run quickly and climb the tree branches. They live alone or in pairs in forests alongside rivers and lakes. The nests are usually located close to the water. The chicks mature quickly.
The kagu (1 species) lives on the island of New Caledonia, east of Australia. These are birds of twilight and night, bluish-grey, heron-sized. The plumage looks dusty, abundantly speckled with powder of the fluffy powder-boxes. They are very bad fliers. These birds are dying out. Both parents incubate one egg. Before that, they have a very picturesque courting. The male and the female stand before each other and lowering their wings to the ground spread the long crests on their heads into wide crowns. Then they twirl around each other, sometimes grabbing with their beaks the tip of their own wings or tails. Then again, they stand beak-to-beak and then they twirl again. The loud melodical mating songs are executed in a duet. The male begins: 'Va-va-va-vava-va'. The female responds: 'Vavava-va'. Then the male again: 'Va-va, vava'. These three lines are repeated for ten minutes in a row.
The trumpeters number three species. They live in small flocks on the ground in the dense jungles of Amazon, Guyana. These are black, short-beaked birds, slightly similar to the guinea fowls. While digging through the fallen leaves, they walk 'in zigzags, raising wings at every step'. Star-tled, they fly high into the trees. There, in a forking branch or in a large hollow, they make nests. Their mating dances are nosy: they run, flap their wings, jump and 'even tumble'. The call is very loud, trumpeting, and melodical. In captivity they quickly become used to people and are very friendly.
Six different crane species nest on the territory of former USSR. The most common, the gray crane nests almost everywhere, save for the uttermost north, the south of Ukraine and Central Asia. The smallest - the demoiselle crane - in the steppe regions from Moldova to the Transbaikal area. The biggest - the Siberian crane - in the lowlands of Ob' and in the tundra of northeast Yakutia. The rarest and the most mysterious is the hooded crane, its head and neck are white, though, and it is a dweller of the dense taiga swamps of Siberia. And, well, the most artful dancer is the Japanese or the redheaded crane. The crane dances, apparently, are not just a mating ritual, but also a simple expression of joy and good mood. Males and females, the old and the very young, whose mating time won`t come soon, they all dance during any time of the year, not just in spring. The Japanese cranes dance in winter, on the snow.
This crane is snow-white, with a black neck, black wingtips and a red cap - very handsome even by itself, and when it dances, then the visitors, people say, are simply spellbound. Recently its dances described in a great detail and illustrated with excellent pictures, by the American naturalist Stewart Cane.
The Japanese crane nests in the swampy valleys of Manchuria and Hokkaido, and also in the Ussuri region and, possibly, in places along the Amur River. It is rare everywhere. In Japan, for example, only 200 of these tancho (as the Japanese call them) have survived.
Like the other cranes, the tancho is always ready to dance, but in January, February and March it dances especially often and good.
The cranes also dance in pairs and in entire flocks.
The pair dance goes as following. Both of the birds - the males and females are indistinguishable in appearance - suddenly stop hunting for 'frogs' and turn towards each other, beaks first. One of the birds begins to bow: it stretches its neck to the partner, bending it slightly downwards in a bow. In this pose, the head and the neck of the crane shake slightly up and down, up and down. Then the bird flaps its wings, and walks around with a dancing step.
The tempo grows with each new turn.
Now both of the birds, standing against each other, jump upwards, flapping their wings. In the jump, the left leg - it is held slightly more upwards than the right - energetically kicks the air. In the zenith of the jump - sometimes it can reach upwards 2 meters or so - both birds spread their wings and it appears that for some moments they literally swim in the air.
Sometimes, after jumping upwards especially high, the cranes do a 'dancing flight': side by side they slowly and elegantly glide downwards and land up to 40 m away from the place where they flew up. Usually after this they stop dancing, shake themselves, and go back to the business of wandering through a meadow.
The dance of the Manchurian cranes contains three other interesting moves. When dancing, they often use their beak to pick up from the ground various small objects: sticks, dry grass, seeds, or even pieces of paper - and the cranes throw them into the air. The second move: the dancer jumps back first to its partner, spreading its wings as wide as possible. Then their black tips, contrasting sharply with the white plumage of the crane, are seen particularly well.
Sometimes the birds freeze before each other, stretching their necks upwards and pressing their beaks to the chests, showing the red caps at the backs of their heads. The wings are raised slightly upwards. Then the heads are lifted so that the beaks now point to the sky and the birds cry piercingly. Usually the choreographic duets are done in an utter silence. But when an entire flock dances, the cranes encourage themselves by crying.
If some bird invites its partner to a ball by nodding, the other cranes, previously peacefully grazing on a swamp, often surround them and also begin to jump. Sometimes an entire dozen of cranes begins to dance. Some do the entire dance, others do only several half-hearted jumps, the third stand and watch, the fourth, which are located far away from the dancers, gather seeds, berries, and insects in the field or clean themselves. But those, who are the closest, cannot help but dance themselves. 'Apparently', one of the zoologists wrote, 'for the cranes dancing is just as infectious as laughter is to us.'
The young cranes do not have to learn the art of dancing from the elders; they hatch already 'educated', with a full knowledge of all of the figures and pirouettes. A crane chick raised in captivity, according to Cane, after five days since birth already could do the crane moves - it jumped high, kicking the air. And also bowed and threw various objects upwards. It never saw how the other cranes danced.
FROM GILGAMESH TO OUR DAYS
At the start of the seventh day
I took out a pigeon and released it;
Having left, the pigeon came back:
It could not find dry land, so it returned.
No, we are not talking about Noah, though the Bible talks about the same subject in almost the same language. Those lines are not from the Bible - but from tale of Gilgamesh, composed 5000 years ago on the shores of Euphrates. The story talks about the first in the world documentally dated experiment on the navigational abilities of birds: 'having left, the pigeon came back'. 5000 years ago, people already knew that pigeons have excellent orientation abilities and always find their home, no matter how far they would fly away from it.
As soon as people figured out those abilities, they immediately began to capture birds and teach them the simple science of mail carrying.
The Roman Pliny the Elder, in the first century A.D., wrote about a certain Cicinius, a great fan of horseracing. Going to the races, he 'had a custom of taking swallows with him, caught under the roofs of his friends' houses'. If his horses won prizes, he colored the birds in an established color, signifying victory, 'knowing very well that each swallow would return to its' nest'. Even more recently, a certain Frenchman advertised his swallows, offering to use their services.
However, the pigeons, undoubtedly, are birds more appropriate for mail messages. They are en-during, well breed in captivity, fly quickly and are sufficiently strong to carry small messages.
The rock dove is the ancestor of 140 different breeds and races of domestic pigeons. 5000 years ago, they were already bred in Egypt and Babylon. Mail pigeons appeared later. Egyptians, an-ient Greeks and Romans send pigeons with messages.
Modern mail pigeons are not direct descendants of the ancient birds: they were created through hybridization of various breeds more than 2 centuries ago in Belgium. Through training and artful selection, the selectioners produced astonishing results: the best modern mail pigeon flies 1000 km in a day!
Pigeon mail has a respectable history. However, in our times, despite the newest means of communication, pigeons carry the mail.
In Britain alone, there are more than 1000 000 of such pigeons. One-fifth their number, 'recruited' into the military, actively participated in the past world wars: many different messages were passed on through them. The Reighter agency, which already in the mid-XIX century, sent mes-sages with mail pigeons, in 1962, having tried artificial satellites, returned to the pigeons for help. They proved to be the most comfortable and quickly means of passing short messages through the blocks of big cities, on whose streets constant traffic jams halt movement.
Lately, many people are attracted by sport competitions of pigeons, which began back in 1825 in Belgium. In those competitions, the number one goal for the bird is to come back home as quickly as possible and often only the last seconds of a multi-hour flight bring victory to the best pigeons.
Pigeons are always released in a certain direction away from home, at one stage of some traditional route. Professionals of this sport know well that those birds, who flew the route several times, return more quickly and more confidentially.
This is the main reason for teaching mail pigeons. First, the birds are released close to hoe. Then the distance grows. Education must help the bird to learn all the landmarks of the route and direct its flight through a narrow corridor of a well-known countryside.
And then comes the final stage of education: a pigeon is taken hundreds of km away from the final links of the route that it had learned piece by piece. Flying through the air, it must not see the usual landmarks, but the birds finds them quickly and flies home by the already familiar path. In USA, there are racing routes going for thousands of km and there are thousands of pigeons that had perfectly 'learned' each of the km in question.
The story of the passenger pigeons of North America testifies about the immense fertility that the pigeons are capable of under the right conditions. It is hardly likely if any other birds flew over the land in such monstrous flocks. The tales about passenger pigeons are read like a fantasy novel.
They lived over the entire territory of USA and Southern Canada. They appeared in such dense flocks in the sky that they literally shadowed the sun. It became twilit as if it was an eclipse. The flying birds covered all of the sky from one horizon to another. The pigeon dung fell from the sky as if they were snowflakes; the buzzing of the wings resembles the whistling of a storm wind.
Hours would pass and the pigeons would go on flying and their lines had neither beginning nor end. No cries nor singular shots nor cannonade could cause the endless 'escadrille' to decline from its course.
The American ornithologist Wilson tells about a flock of pigeons that flew over him for four hours. The flock lasted for 360 km! He counted the approximate number of birds: an impossible number was the result - 2,230,272,000 pigeons.
Audubon the ornithologist talks about a flock of passenger pigeons that numbered 1,115,136,000 birds! This means that one flock of pigeons had much more birds than all of them in such a country like England or France.
Could such a fairy tale multitude of birds be exterminated quickly? The sad fate of the passenger pigeons says that it is possible if it is undertaken the right way.
The passenger pigeons were destroyed in all ways that could work. They were shot at from rifles, guns, pistols, muskets of all systems and calibers. Even pots of sulphur, lit under the trees where the pigeons spent the night, were used. The birds were caught in nets, struck with sticks, stones. The flocks of pigeons were so dense and sometimes flew so low that the colonists knocked them with boards. The anglers, when the pigeons flew over them, knocked them down with oars. Not one missile, sent upwards, fell back without taking with it a pigeon or two. They say that farm workers learned to knock down flying pigeons with sheep shears. Even dogs jumped on hills and caught flying pigeons jumping into the air. Simply amazing!
When pigeons flew over forts the soldiers loaded canons with buckshot and shot down hundreds of birds. One of the American authors of the middle XIX century describes the city of Toronto when a big flock of pigeons flew over it. For three or four days, while the pigeons flew over the city, the walls of its houses shook from endless fire, as if an enemy had taken over the streets. All shops, all establishments were closed. People besieged roofs of houses. All sorts of rifles, pistols and muskets were used. Even the honorable members of the municipal council, lawyers, flourishing entrepreneurs and the sheriff of the county proper could not refuse themselves a participation in this amusing 'sport' - extermination of harmless birds.
The passenger pigeons fed on acorns, chestnuts, beech and other nuts that grew in plenty by the virgin forests of North America. The pigeons had to often switch places of feeding, but they usually spent nights in the same place. There they were impatiently awaited by crowds of people that gathered from everywhere.
Audubon tells that one place where the pigeons spent the night consisted of a portion of woodland about 5 km wide and 65 km long. The pigeons did not yet appear, and the 'hunters' were already camping around with wagons, barrels to salt meat and other equipment. Two farmers brought a herd of pigs 140 km over to feed them on pigeon meat.
When the sun set, a dark cloud appeared on the horizon. It was the flying pigeons. They approached quickly. Thousands of pigeons were killed by first shots but newer and newer legions of birds appeared. They took over all of the trees in the forest, not a branch was left free. On some branches the pigeons sat in several rows one on the back of another.
And the air around shook from endless firing, from crashes of branches that fell beneath the pigeons' weight, flapping of a million of wings. You could not hear a neighbour's words in the hellish noise. Even gunshots were recognized only by flashes. The slaughter lasted all night. By morning mountains of dead and dying birds lay beneath the trees.
The Europeans despised the laws of the 'ignorant' natives that forbade hunting the birds during their breeding period. They killed the nesting pigeons by millions. In the state of Michigan, in 1878, the nesting colony of the pigeons occupied all trees in a forest 15 by 57 km. The nest site in Kentucky took over a space that was twice as big. Each tree had hundreds of nests and often branches broke beneath the weight of quickly growing nestlings.
When the nestlings became edible, the farmers gathered from everywhere. They arrived with their families, workers, brought herds of pigs. The trees with nests were toppled to the ground and the yet unfeathered nestlings were killed with sticks.
USA had many thousands of professional 'hunters' of pigeons who earned great money by the rates of that time, up to 10 pounds of sterling per day. Their 'enterprise' was well established. An entire net of agents telegraphed messages about appearances of new flocks of pigeons here or three, where they spent nights and where they flew. Immediately the providers raced there.
The development of railroads ensured the quick provision of hundreds tons of dead pigeons on the country's markets. Daily, for example, from the nesting colony of Michigan came 12.5 thousand birds via the railroad and the mass harvest during the breeding period from March to July accounted for 1.5 million of birds.
This was the 'harvest' of a single colony. In all of USA and Canada hundreds of millions of birds were shot during the 1870s!
Already in 1848 Massachusetts released a law banning the hunting of pigeons with nets. Three years later the state of Vermont began to protect all the non-hunted birds, including the passenger pigeons. Laws that forbade hunting them were soon accepted in other states as well. But who cared about them when big business was involved!
In 1880 the country still had significant flocks of passenger pigeons but 20 years later not a trace of them remained. The disappearance of a fantastically abundant species was so sudden that the Americans, it seems, still cannot recover from the unexpectedness. Several 'theories' were invented to explain the shockingly fast, 'like a dynamite blast', disappearance of the pigeons. Some suppose that all of the pigeons drowned in the Atlantic Ocean, when they 'immigrated' to Australia. Others believe that they moved to North Pole and froze there.
At the beginning of the 20th century several passenger pigeons lived on in the zoos and among various amateurs. The last representative of this species (called 'Martha') died in the city of Cincinnati in September of 1914.
'DEAD AS A DODO'
In 1507 the Portuguese Pedro Mascarenas discovered islands in the Indian Ocean that were later named after him. They were a comfortable mid-way station on the path to India and soon crowds of adventurers, like glutinous locusts, have filled them. The ships' crews filled up their food sup-plies here, killing everything that was alive in the forests of the archipelago. The hungry sailors ate all of the giant tortoises, and then they took on the dodos.
The Portuguese called them 'dodo' while the Dutch, who arrived later - dronts. Many people laughed at the bizarre appearance of the fantastic-looking birds, clumsy and fat, like overfed chickens. Helpless dodos, heavily waddling from side to side and helplessly flapping the puny stumps of wings, unsuccessfully tried to escape from humans by running.
The insides of ships were stuffed with dead and living dodos. The Dutch colonists brought do-mestic pigs, cats and... macaques onto the Mascarenas islands. They began to destroy the eggs and hatchlings of dodos with no less effort than people did. And together, people and animals had exterminated all dodos by the end of XVIII century. Several puny skeletons in museums, images in paintings of Dutch painters and the proverb 'dead as a dodo' - it is all that remains nowadays from the amazing birds.
The ornithologists were not able to learn much about dodos. Those huge, bigger than turkeys - they weighted 18-20 kg - fat and clumsy birds were, apparently, degenerate pigeons. The 'bald' head of the dodo was decorated by a massive hooked beak and instead of tail and wings small bunches of feathers were protruding.
The three islands of the Mascarenas archipelago - Mauritius, Reunion and Rodrigues - lived, apparently, three species of dodos. The Mauritius or dark dodo left behind the most important legacy for biology: several bones, a leg and a beak (or two legs and two beaks?), besides a dozen of drawings and paintings, where its' portraits were masterfully drawn.
In 1599 the admiral Van Nek brought the first live dodo to Europe. The strange bird caused a large commotion in admiral's homeland of Netherland. People could not stop staring. The paint-ers were especially attracted by its grotesque appearance. Peter Holstein, Hoofnagel, Franz Franken, other famous painters got attracted to 'painting dodos'. At that time, people say, more than 14 portraits of the captured dodo were drawn.
Another live dodo arrived in Europe half a century later, in 1638. An amusing story happened to this bird, or rather its stuffed remains. The dodo was brought to London and showed it to every-one who wanted to see it for money. And when the bird died, it was skinned and stuffed with straw. The stuffed dummy passed from private collections to one of Oxford's museums. For an entire century it stayed there in a dusty corner. And in winter of 1755 the keeper of the museum decided to undertake a general inventarization of the exhibits. For a long time he confusedly stared at the dummy of a surreal bird half-eaten by moths with a bizarre inscription on the label: 'Ark'. And then ordered it to be thrown into a waste bin.
Fortunately, a more educated person was walking past than bin. Surprised at his unexpected luck, he pulled the hook-billed head of the dodo and a clumsy leg out of the dump - all that remained from it - and hurried to a curiosity dealer with his priceless finds. The saved leg and head later, this time with great honors were accepted back into the museum. Those are the only relics in the world that remained from the only dummy of the dragon-like pigeon. That is according to Willy Ley, one of the experts of the sad history of the dodos. But Dr. James Greenway from Cambridge in his excellent monograph on the extinct birds states that the British museum keeps one more leg, and Copenhagen - a head that unquestionably belong to a once living dodo from Mauritius.
The last dodo was seen there, on Mauritius, in 1681. And a century later the inhabitants of the island already forgot that the forests of their homeland once boasted chickens that weighted a stone. When at the end of the XVIII century naturalists followed the tracks of the dodo and the search led them to the island of Mauritius, everyone, who was asked by them for advice, doubt-fully shook their heads. 'No, sir, we don't have such birds and never did', said both sheepherd-ers and peasants.
The dodo hunters, disappointed and embarrassed, returned with nothing. But J. Clark, disbeliev-ing the local legends, stubbornly continued to search for the forgotten chickens. He climbs mountains and swamps, dug earth, burrowed in the dusty piles of river shores and ravines. Luck always comes to those who stubbornly seek it. And Clark got it: in one swamp he unburied many massive bones of a big bird. Richard Owen examined those bones in detail and proved that they belonged to the dodos.
At the end of the 19th century the government of the island of Mauritius ordered to undertake a more detailed digging on the swamp discovered by Clark. Many bones of dodos were found and even several complete skeletons, which currently decorate chambers of some museums in the world, that hold the most valuable collections.
The island of Reunion, next to Mauritius, was made famous by the white dodos. They outlived their dark relatives by more than half a century: the last white dodo was killed, apparently, in 1750.
Reunion's dodos were little different from Mauritius' dodos. But apparently they were much lighter in color, almost white. They were called solitaires because the greater part of their lives these birds lived in solitude.
The solitaire is also the name of a dodo of a very special species and even genus, as some scien-tists believe. This second 'solitaire' lived out its days on the small island of Rodrigues. Its' wings, or rather what remained from them, were longer than those of the other dodos and they ended in some strange rounded bones, one per wind, the size of a musket bullet. These 'bullets', like brass knuckles, were using by fighting dodos to hit each other. They used them to fight off dogs too, and they also desperately bit. The beaks of the feathered hermits were not small, they were hooked and sharp, they delivered quite painful bites. So they were not fully helpless birds. And their appearance was quite carnivorous and intimidating, not very appropriate for vegetarians. For the dodos only fed, people say, on leaves, fruits and tree seeds.
A constellation on the sky was named in honor of Rodrigues' dodo. In June of 1761 a French astronomer Pingre spent some time on Rodrigues, observing Venus set against the solar disk that the planet was crossing at that time. Five years later his colleague Le-Menie to preserve for cen-turies to come the memory of his friend's presence on Rodrigues and in honor of the amazing bird that had also lived on this island, named a new group of stars, discovered by him between Draco and Scorpio, as the constellation of Solitaire. Wanting to mark it on the map with a symbolic figure, as according to the custom of the day, Le-Menie turned for advice to a then famous in France 'Ornithology' of Brisson. He did not know that Brisson did not include dodos into his book, and when he saw a bird's name of solitaria, i.e. 'hermit' in the list of birds, he redrew the bird in good conscience. And of course he mixed-up everything: instead of the impressive dodo, the new constellation was crowned by a not very presentable blue rock thrush - Manticola solitarius. It lives even now in the south of Europe, and among us - in Transcaucasia, Central Asia and Southern Primorye. Dodos were unlucky again. A series of fatal misadventures had marked the last page of their history with a peculiar end.
The last of the dodos was killed on the island of Rodrigues' in the very end of XVIII century. Not one of those 'unbelievable' birds had lived to the enlightened 19th century.
BIRDS WITHOUT NESTS
The strange name 'goatsucker' was born by a misunderstanding: during the night these birds fly among the grazing livestock. They are attracted by insects, but the rumour, back during the time of antiquity, decided that the birds suck the milk of cows and goats. Their wide mouth is supposedly good for it, an idea that is wrong, of course.
The goatsucker males arrive into our forests, steppes and semi-deserts from Africa, to Siberia - from India, earlier than the females. They arrive at night, and during the day, adhering to ground or to a branch, sit immobile, closing their eyes. It is hard to see them.
But they give themselves away in the evening's twilight. A long, 'purring', or rather, suppressively crackling, somewhat 'accented' trill - 'trrrr' - a goatsucker male's song can be heard over scrubland and fields. After exclaiming a sharp 'quwick', the male flies off a tree, on which it has 'leked' and flies an un-even flight, twisting between the trees. After raising its wings, the male flaps them above itself. It spreads its tail like a fan to show the white spots located on it. The female responds with a cry or flies towards the summons. The male follows.
They do not make nests. They lay two eggs straight onto the bare ground, upon the fallen leaves and needless, onto moss, even upon a forest path, sometimes. The stiff stems that lie there are cast aside by the female, so that they would not get in the way. The male incubates less than the female does, usually during the twilight and at night. They lure the enemies away from the clutch, pretending to be wounded, dragging their wings and fluttering. And then they roll away the eggs, moving backwards, aside for several meters, because their old location is dangerous.
The nestlings start to crawl around only after several days. During the day they hide under their mother's wings, but once the sun sets, they shake it, touching the bristles around the mother's beak: they want to eat. Mother flies to hunt.
The nightjars and goatsuckers fly with closed beaks. Only just before grabbing a beetle or a moth, does their unbelievably wide mouth opens. They bring the insects in a throat sack. Their nestlings meet them, squeaking excitedly. The parents submerge their beaks into the nestlings' wide mouths and give them the prey.
The nestlings grow quickly. They do not go far away from the bare patch on which they have hatched for two-three weeks, but their 'bathroom' is off to a side: they surround the 'nest' with a narrow white ring of dried-out feces. Later, when they start to fly, they still live with their parents until August - September, when they depart for warmer climes. At that time, each goatsucker family owns and protests a hunting territory of several hectares.
In some parts of Central Europe the goatsuckers have a second clutch in summer. In that case they divide the parental responsibilities: the male takes care of the first brood, and the female hatches the second.
When the weather is bad, the insects are few, the goatsuckers, just as the swifts do, freeze in immobility, their body temperature falls, and they economize their energy. Such a 'hibernation' can last for many days and nights.
'A group of the nightjars is one of the most perfect examples of the mimicry that can be found in all of the animal kingdom among the species of such size. These birds are clothed in soft cryptic colours, reddish-brown, yellowish-brown, brown, golden-brown and ashy-grey, or in neutral-sandy colours... The nightjars sit, firmly adhering to the ground, invisible, they allow to almost step upon them, before suddenly leaping up, to fly away with an easy and dexterous flight' (H. Kott).
In Iraq, at least twenty Egyptian nightjars hid during the day, upon a small patch of bare ground, half a hectare in size. But it was absolutely impossible to notice them until the birds flew away straight beneath the feet!
The mimicry of the Australian frogmouths is no less perfect. The birds sit vertically on branches or fences, closing the eyes into narrow slits, and are so similar to broken-off sticks that it happened that people, coming close, would put a hand upon them, unsuspecting that it's a bird, not a piece of wood! 'Trusting in its amazing imitation of nature, it remains frozen and immobile, and doesn't try to fly away, if it isn't pushed-off by force.'
Immobile and invisible they incubate their eggs as well...
'...in a fork of horizontally-positioned branches. This allows the bird to sit on the nest, putting the tail onto the branch and putting the head between the branches, from where it can see everything around it. It sits, spreading over the nest, and its head with the bunch of bristles above the beak gives the bird the appearance of a piece of dry wood... In this position it appears lifeless and flies only when the observer climbs upon the tee almost to the very nest' (Mellor).
The tiniest nests, on an absolute scale, belong to the hummingbirds: half the size of a walnut shell, in some cases even smaller, in many others, however, larger. And the birds themselves are incredibly small! The dwarf hummingbird is the size of a bumblebee; that bird weighs slightly over 1.5 grams. The smallest of the shrews and the dwarf hummingbird - are the record-holders for the smallest creatures among the warm-blooded animals. But many of the hummingbirds - and there are 321 species of them, all of which live in America! - are approximately the size of a finch. One species, the giant hummingbird, is the size of a swallow.
The smaller a warm-blooded animal is, the greater its relative body surface is as well. This is followed by considerable expenses of energy for sustaining the necessary temperature balance; heighten exchange of nutrients; and a greater consumption of oxygen. Therefore, the heart of these small birds must be appropriately large, and it must beat in a heightened rhythm, and there must be a lot of haemoglobin in their blood. All of this, as was shown by experiments, is present in the hummingbirds.
They consume more oxygen per every gram of weight than any other living creature, as far as science is concerned, at least. 3-8 times more than, for example, a crossbill, 68 cubic cm per gram of weight in an hour. (That is when flying.) The heart is proportionally thrice as large, and a hummingbird's erythrocytes are twice more numerous than, say, a pigeon's. The energy source for a living creature is food. In a day, the hummingbirds eat twice their body weight. But at night, when they are asleep, the exchange of their nutrients falls in order to economize the energetic resources, and the temperature falls to 20-17 degrees. The birds spend the night hibernating, just as the swifts do during bad weather.
Originally it was thought that the food of the hummingbirds was only the nectar of the flowers. But this food has few of the proteins, the main components of the internal metabolism. When the researchers tried to feed the hummingbirds only with sugary syrup, the birds quickly died of starvation. Apparently, even those that regularly sup nectar also feed upon many small insects that hide in the flowers. Many other hummingbirds feed primarily on insects and spiders.
They are excellent flyers: they can dodge to any side from the 'suspended' position or from a 'cruising' flight - even backwards! They flap their wings often, just as insects do: 20-30 flaps a second for the large species and up to 70, and even 100, for the small ones. The flight is very quick. According to some data, up to 100 km/h! For such tiny birds this is an impossible achievement...
These fast and dexterous manoeuvres in the air save the hummingbirds from their enemies. However, the flying Lilliputians prefer an active offense. Having avoided, by a dexterous maneuver, a direct assault, they often launch their own attack: utilizing speeds, close to the speed of an arrow fired from a bow, they attack from the flanks and the back, even large birds, even predators, inflicting 'pinpricks' with their sharp beaks, aimed at painful spots, for example eyes, and causing the enemy to quickly retreat. That same spot, the eyes, is where the hummingbirds strike the tree snakes that approach their nests.
Almost all of the hummingbirds are colored very brightly. The shine as if they were gems. But the main colors in their plumage are dark - black and brown pigments. The colours of the rainbow, with which the hummingbirds glimmer, are sunlight, reflected by the structure of their feathers. Therefore, after every turn, under every new angle of illumination, the same bird looks to be differently colored.
Basically, they are inhabitants of the American tropics. Ecuador has housed especially many of the various hummingbird species. But one species nests in Patagonia, and two in North America (the first - in the western states of USA and provinces of Canada up to the south of Alaska, the second - in the eastern USA up to the south of Canada). The hummingbirds that have reached such high latitudes migrate to spend the winter in the subtropics. The two North American species fly a long journey - up to 5 thousand kilometers, up to Panama. The hummingbirds that nest on the east of USA fly 800 kilometers (without landing!) over the Gulf of Mexico.
The kingfisher is a small beautiful bird that glimmers with blue and red, sometimes flashing like a bright gem low above the water of slow-moving rivers, or sitting on a rock or a tree branch near water and then falling down - into the water. If it does not miss, then soon it is once more on a branch, rock or in its nest with a small fish in its beak.
The kingfisher often misses. It was calculated that about only one in ten dives ends in dinner. The rest are clear misses. The small fish, up to 6 cm in length, are the kingfisher's prey. It also catches aquatic insects, more rarely - froglets. The fish it usually catches are sick, slow moving. Therefore the kingfisher is not a pest of the fishing culture. Per day, 10 of such fish are a kingfisher's meal. If it has hatchlings, it requires 6 more extra fish, but of an even smaller size.
The hatchlings are raised in burrows. The burrows are dug in riverbanks, half a meter, a meter above the waterline, and sometimes even higher - if the spot is good.
During the mating game, the male offers the female a fish, just as the terns do! As soon as pairs are formed, often for the rest of the life, the nest territory is chosen; it is firmly protected, the female begins to dig in the riverside's ground with its beak on the wing. The male takes over this from time to time. Then, when they have dug a small niche in this manner, the female sits on its edge and digs out a tunnel about a meter long with its beak. It uses its legs to throw the ground out. The male, standing behind the female, also throws the soil out with its feet when the burrow becomes deep enough. The burrow ends with a small nesting chamber about 10 cm long and 10 cm high.6-10 eggs are incubated there for about 3 weeks, without any lining material being there. The lining of fish bones, scales and other undigested remains, vomited out as pellets, and accumulates later, as the birds become more comfortable with their burrow.
Later, in the beginning of July, there may be even in a second clutch, and in some places - even a third one. The hatchlings are fed on really small fish. According to some data, the male does not participate in this, according to another - the male does brief feedings, sometimes even of two clutches from two different females in two different burrows.
The chick, which sits closest to the exit of the burrow, gets the first portion. Then it is pushed aside and is replaced by another chick. It goes so until all are fed. Then the first chick ends up at the exit once more, it immediately turns around and spurts out the liquid dung. The liquid does not always get outside, therefore a kingfisher's nest is dirty and kingfisher parents have to reach their offspring through excrement of all sorts. Their plumage gets dirty - they have to bathe many times a day.
As soon as the young kingfishers can fly, they immediately leave their parents. The male and the female break up soon afterwards until the next spring, unless they have a second clutch.
There is only one species of kingfishers in Europe and Russia. These birds do not live north of south Scandinavia and Petersburg, and in Siberia they do not go north past the lake Baikal. Also, the common kingfisher lives in Africa and South Asia.
The common kingfisher is the member of the subfamily of the so-called 'aquatic' kingfishers. Their life is tied to water and fishing. Some dive for prey seeking it from rocks or branches, others - while flying low above water, as the terns do.
There are also 'arboreal' kingfishers. They catch fish only on occasion; therefore the aquatic habitats are not very attractive to them: they live in parks, dry scrublands, in mountains and semi-deserts. They feed on insects, frogs, lizards, snakes; they steal eggs and young from their avian neighbours. They all live only in the eastern hemisphere and many of them are less colorful than the piscivorous kingfishers are. They nest in tree hollows and termite mounds.
The most famous of these kingfishers is the kookaburra, a bigheaded, long-beaked, robust bird, approximately crow-sized. There are many legends regarding it. On dawn and dusk, in shrubs and scrubland, spread over the dry hills of Australia, you can hear loud infectious laughter. This strange merriment confused even the first Dutch colonists who landed on the Australian coast. They gave the name 'Laughing Hans' to this sylvan bird.
The kookaburras also living in Tasmania and Papua New Guinea. They begin their daily calls with merry laughter in the morning, noon and evening. They say that you can supposedly time clocks on the kookaburra's laughter.
'Laughing Hans' is one of Australia's attractions. The tourists dream of hearing its laughter. Having appropriately appreciated the popularity of their feathered neighbour, the Australian radio begins its programs in an odd way - with the kookaburra's laughter.
The kookaburras steal poultry chicks: it seems that the farmers should not like them. But they destroy many venomous snakes, and for that people forgive their petty thievery, breed them in the parks and have even introduced them in the Australian west, where the kookaburras did not live before.
The kookaburras have often bred in European and USA zoos. Both parents incubated 2-4 eggs for 25 days. After a month the hatchlings abandon the nest, but the parents fed them for another 40 days, mostly the male, since the female was already busy with a new clutch. When the new generation of the laughing birds reached 40 days of age, they 'laughed' for the first time.
HOOPOES AND HORNBILLS
Behind abandoned buildings, farms, on meadows, in forest clearings, but the forest itself must be sparse, on the south of the former USSR, a mottled crested bird walks on the ground, shaking its' head forwards, pigeon-style. The crest is opened and closed like a fan. The long, downturned beak is thrust into knots of dry grass, under rocks, into cow 'patties'. It gathers various small insects. And if a large six-legged prey is caught, it will be slammed into the ground thusly, that the wings, legs, head will fall off. The soft abdomen will be eaten.
The swallowing goes thus: the prey will be thrown upwards and swallowed by the open beak. The bird's bear is long and thin, while the tongue is short, it cannot pull prey held by the end of the beak into the mouth. Hence, the bird must joggle every time it eats.
In general, the crested bird is not meek. However, if a person approaches, it flies. It flies beautifully, flying upwards and descending, and indeed right then it looks like, as people have written, 'a big mottled butterfly'. The flight is not fast, seemingly even feeble, but dexterous and maneuverable, so even the birds of prey, skilled in attacks, cannot always catch the hoopoe. (This crested bird is called the hoopoe in English language).
'By fast turns in the air the hoopoe avoided the strikes of the peregrine from above and the attacks of the harrier from below. The fight went for two or three minutes, until both carnivores didn't grow tired and left the hoopoe alone' (R. Cheeseman).
The female incubates about a dozen of greyish eggs around 16-17 days somewhere in a tree hollow, between rocks, in a building niche. The male feeds it, and then - the young hoopoes as well. For about three or four weeks while they are sitting in the next, and then for another ten days after they leave.
The hoopoes are born covered in thin fluff. They beg for food, opening brightly red, fringed with white, bills. They defend from the enemies in the manner of the skunk. Turning around, they squirt liquid dung that smells so unpleasantly that a rare person will endure such shooting, cats and dogs clearly avoid approaching nests of hoopoes. In addition, the posterior gland of the hatchlings and the incubating female at that time produces a strongly and foully smelling oily liquid, which creates extra support during the 'chemical' defence.
The common hoopoe also lives in Africa, on Madagascar, in South Asia. In those countries also live its' six relatives - the tree hoopoes. Many of them are dark blue and have no crests. They agilely climb tree trunks and branches, defending with the same stinking liquid. The common hoopoe intimidate the enemies by hugging the ground with outspread wings and an upturned beak. The tree hoopoes imitate venomous snakes in the dark tree hollows by slow head movements, as the wrynecks do.
When hiding from snakes, primates, and birds of prey, the relatives of the hoopoes, the hornbill birds, when they incubate the eggs... they seal themselves in tree hollows!
Actually, only the female does that. The male feeds her and later the hatchlings through an opening that is left specifically for this purpose. Earlier it believed that the male by its actions has encased the female so and the female cannot leave without the male's help. New observations proved that after finding a tree hollow with appropriate dimensions, the female enters it and from inside it covers-up the entrance with damp ground, dung, fruit flesh, often mixing it with saliva. The male only brings it the necessary material or slightly fixes it from the outside.
The females incubate for three-four weeks up to five eggs in the smaller species or only two in the larger. Those, that feed on fruits, usually it is the larger hornbill species, stay in their voluntary seclusion for three-four months, feeding only what their spouses give them. While they are sitting in the tree hollow, they moult. Males feed them a-plenty: they bring in their throat, since they have no crop, several dozen figs, for example. The females, by the end of the 'house arrest' visibly gain weight, the males, on the contrary, lose it, exhausting themselves by caring about sustenance of the sealed-away family.
The smallest of the hornbills, (Tockus, 10 African species), feed on insects. When the Tockus chicks grow up some, the male, flying with each insect in its' beak, cannot in time both catch the prey and deliver it. In short, the male cannot support the family by itself for long. Therefore, the female must in two-three weeks after the chicks hatch abandon the comfortable solitude and help the male feed them. After the female breaks the clay lid, straight away the parents bring the chicks, (or just one chick in some Tockus species), the necessary materials and the hatchlings seal themselves up, in order to spend the next two weeks in safety, until they leave the nest.
Only the helmeted hornbill has not porous, but solid horn, completely full of a horn-like substance. The rest of the family have beaks with strange 'structural' excesses, but they are very light. In case of the helmeted hornbill, it is quite heavy: complete with the skull it weights up to 320 g, only ten times less than the bird itself.
Previously, the helmeted hornbills were numerous in Malacca, on Sumatra, Borneo. From there, their massive bills, brought to Europe, were sold in Middle Ages as 'ivory'. The carvings and items made from them were not cheap.
In the hornbill family, only the female ground hornbills, (two species in Africa) do not seal them-selves up and the lifestyle of these birds is different - not arboreal, but terrestrial. They are black, with a blue 'face' (or red in another specie), with a red throat sack, that can stretch a lot. They are common birds of the savanna. They catch insects, especially plenty of locusts, lizards, small rodents, even snakes. Then again, the other hornbill birds too easily manage snakes. They see a snake, summon their relatives with cries, surround it, and tear it with their bills, putting up their wings as shields against snakebites.
The ground hornbills breed in the rainy period, as all the hornbill species that live in dry places do. At that time their bass cries are heard, they resemble a distant lion roar. They nest mainly in baobab hollows: there, where those trees go, the ground hornbills are also plentiful. The female incubates two eggs for a month. The chicks stay for another three months in the nest. Then they stay with their parents for another nine months.
WHY DOES A TOUCAN NEEDS SUCH A BEAK?
The toucans' beak has surpassed all the mental norms! It is huge in comparison with the bird: in some cases it is longer than the body is (not counting the tail). Orange, red, yellow-black, green, often multicolored. Up to five different color tones in its coloration! It is thick but light, not massive. Saw-like on the cutting edge. Very impressive beak! Why the toucan does need it?
Once it was supposed that the toucan uses the grandiose bill for protecting the entrance to a tree hole once it is inside. Later it was discovered that while he could successfully follow this advice, it does not. In case of danger it flies away from the hole. Of course, a big beak is very helpful in picking fruits from thin branches, while the toucan itself sits on a sufficiently thick branch that still endures the bird's weight without breaking it. But in this case a long thin bill would be just as sufficient. The extreme thickness of the 'nose' just impedes the bird, and its multicolored decoration appears to be just irrelevant. Therefore the scientists suppose that the toucan's bill is most likely a signal sign that makes it easier for the birds to discover and identify each other. Or it is a sexual evocator, similar to the peafowl's tail. In daily, so to say, interactions of the toucans the beak has an important role. They often drum their beaks on the branches, creating sounds that are attractive to their partners. Or they fence with them, while playing. They juggle berries: one throws, the other catches it, using the beak.
A thick beak can also do as a weapon. Attacking the neighbours' nests, the toucans bravely use their 'noses': their impressive dimensions and bright, often black-orange (warning, wasp-like) coloration frightens even small birds of prey, and the latter shamefully abandon their nests. The toucans quickly swallow the eggs and the chicks and fly away. In flight, the big beak is harmless: here the toucans are usually attacked by the birds robbed by them.
This beak can be used to 'beat down' a small snake, lizard or a spider, to catch flying termites, when the latter are swarming, or to grab a fish from the water, and, of course, to eat fruits and berries - the main food of the toucans.
But to peck at a tree, even a rotten one, this magnificent beak is an inadequate, though some toucans do try to do that. Therefore, they have to, after evicting the owners, to occupy the woodpeckers' holes and the various natural spaces in the tree, widening the entrance, if it is necessary. The eggs are incubated right on the bare wood. In old tree hollows, where the toucans raise their young year after year, forms a carpet out of the indigested fruit seeds, which, apparently, they burp there precisely for that purpose.
The toucan hatchlings are naked, red-skinned, and blind. The eyes open very late - after three weeks! The feathers grow very slowly too - at a month of age they still do not have proper feathers. There are heel corns on their legs, a protection from lying in one place for too long. For they sit for a long time on the unyielding wood of the tree, for about two months.
The big toucans are poor fliers, and reluctantly go to air. They flap their wings and then glide downwards (apparently, the beak pulls downwards; although it is relatively light, it is still too big, acts as an impromptu 'sail'). The toucans' flight is wave-like. They prefer to jump around in the branches. Cheerful birds; they often play with each other, they jump, knock their beaks on the branches and cocking their heads, they listen to their 'music'. They bathe with noise and with cries in the forks of thick branches, where rainwater gathers. Curious, one may even say mischievous, birds, but they are friendly with each other, do not abandon their wounded kindred, but altogether, as the crows do, attack the enemy.
In the evening, before going to sleep, the yellow-beaked toucans initiate duet 'songs' one and the same, selected, tree. Although, their wild cries are hardly a song. Sitting tete-a-tete and raising the grotesque beaks to the sky, in a strange, bird language, cry: 'Hi-knuk! Hi-knuk!' The piercing cries of the other toucans resemble rather the croaks of the frogs, puppy barks.
The arassari toucans sleep in tree hollows in companies of five-six birds. They sleep thusly: the big beak is lying on the back, and the tail is thrust upwards and forwards, over the beak: 'The last bird pulls itself into this space backwards, and its tail is lying on its back at that.'
In many arassari species the males are colored differently from the females: the head, the chest, the neck are black (in case of the females - chestnut or dark grey). The true toucans are coal-black, with blinding orange, yellow or white spits on the throat and chest, at the base of the tail. The lower side of the tail is red. The bare skin on the 'face' around the eyes is orange, blue, green, yellow. The eyes are usually indigo.
The forty species of toucans (11 of them are the true toucans, of the ramfastus genus) live in Central and South America.
THE WOODPECKER FINCH
The Galapagos or Darwin's finches are famous in that after studying them in 1835, Charles Darwin received rich material for proving his theory on the origin of species. In the evolutionary genealogy they are close to the yellowhammers than to the true finches. For more than a century now the 14 species of the Galapagos finches attract the attention of scientists. Lately the extraordinary abilities of the woodpecker finch are being studied.
It was seen in a film shot on those islands by a group of operators led by a famous German ornithologist Able-Abesfeldt.
It was shown how after knocking the tree trunk with its and listening attentively to the sound, the finch discovers if there are worthwhile beetle grubs under the bark and in the wood.
How afterwards, if the grubs reveal themselves by running in fear, the finch tears off the bark, often using a twig as a lever, finds the grub's passageway and then... then something impossible happens! The finch breaks off with its beak a cactus spine and grabbing it, sticks the spine into the hole, left in the wood by the beetle grub. It energetically moves the spine through there, trying to stick the 'worm' or chase it out from the labyrinth of passageways made in the bark and the wood. Often its inventiveness is immediately rewarded, but sometimes the finch has to spend a lot of effort before the fat stupid grub leaves its wooden halls, trying to save itself from the annoying spine by mindlessly fleeing from it.
Then the finch, sticking the spine into the tree or holding it in its claw, grabs the grub.
If there are no spines, the woodpecker finch rips off a small branch with its beak, tearing twigs off it. It breaks the branch itself thusly so that it would be easier to work with it.
Able-Abesfeldt brought several finches from the Galapagos Islands home to Germany. They lived at his place in a cage and he observed them. One of the finches, when it was sated, loved to play, as a cat plays with a mouse, with the mealworms that it normally ate. First the finch hid them in the various holes and cracks in the cage, and then, after making a lever from a branch, extracted them from there. Then it hid the mealworms once more and against extracted them.
Able-Abesfeldt decided to discover if the woodpecker finches are born with the ability to manipulate sticks or do they learn to, so to say, from the example of the older, experienced finches. He rains a young finch in a full isolation from the other birds of its species. Once the scientist gave his ward several cactus spines. The finch looked at them attentively for a long time. It took one spine into the beak but did not know what to do with it and threw it out. Then it took the spine again, even tried to stick into a crack, but when it saw a mealworm it threw the spine out and began to extract the mealworm with the beak.
Later the finch did manage to somewhat learn how to use the 'tools', but it held them in the beak in an unsure and clumsy way, and selected them without any idea of what to do: the finch often took soft grasses, leaf veins. Of course they bent, tickled the grub, and the bird just wasted its time.
Able-Abesfeldt concluded that the desire to take 'stick-like' tools into the beak and to extract the grubs from the various tree holes is something that the woodpecker finches are born with, but the working experience and the tricks of the trade is something that they acquire when practicing.
The example of the other, knowledgeable birds also plays a big role here. It can be said that the theoretical knowledge of this business the finch receive as a gift from nature for their first birthday. It is programmed into their genes. But the field experiences and the technological nuances of catching the grubs must be developed by them personally.
When the first explorers penetrated the inner areas of Australia, there they saw many wonders: egg-laying mammals with bird beaks on their heads, marsupial mammals, bird incubators and also some bizarre, flower-decorated bowers.
They were usually found among short shrubs. Small, twig-lined platforms. Other, longer twigs were stuck towards each other in the ground, approximately 50 cm apart. Their upper ends were bent towards each other, forming a sort of a roof over the platform.
Before one of the bower's entrances, on ground, spread on a space that was wider than the bower itself, were hundreds of various colored knickknacks: shells, dead cicadas, flowers, berries, mushrooms, stones, bones, bird feathers, bits of snakeskins and many other strange things.
Recently one of these collections had even a toothbrush, knives and forks, children's toys, ribbons, cups from a coffee set and even the coffee pot itself, buckles, diamonds (genuine!) and an artificial eye.
The builders themselves were not encountered at the sites of work: the black birds, which scurried nearby, did not even appear to be connected. The ideas varied. Captain Stokes, who was one of the first explorers of the inner areas of the fifth continent, came to a conclusion that these bowers were made by native women for their children. And the Australian governor of that time, Sir George Grey, was an author of another 'hypothesis': the bower was made by kangaroos, as he apparently supposed that that eccentric animal is capable of anything. It was noticed only later that the bowers were made exactly by the small birds that were previously ignored.
Externally they are quite ordinary. The males are bluish-black, similar to Siberian black crows, and the females are yellow-green. Still, there are many different species and they are not colored alike. The ones talked about earlier are satin bowerbirds. Their bowers were seen in 1839, and later studied, by John Gold, one of the first specialists of Australian birds.
Another bowerbird is colored like the Russian oriole and looks like a thrush. The gardener bird decorates its conical bower mostly with moss and flowers that it positions with great taste. A small meadow is made before the bower. It is framed by a mossy border and forest flowers, ber-ries and beautiful stones are scattered through it. The bird daily replaces the withered flowers with fresh ones.
And its' relative and neighbour, the New Guinean bowerbird puts a carpet of wild roses, covered with bright fruits, before its bower.
18 species of bowerbirds live in Australia, Papua New Guinea and the nearby islands. Almost all of them build various sorts of bowers, tents or 'towers' around young trees from sticks, reaching sometimes two or even three meters in height, building them, rising them up for several years! Only the cat bowerbirds, named so for their mewling cries, do not build anything, but decorate their leking place with leaves from certain trees and clean it from garbage. When the leaves wither, they carry the leaves away, rip new ones with beaks and scatter them upon the leking place that is surrounded by a small moat made from sticks and twigs.
Two species of bowerbirds even color their bowers by their own paint!
A big specialist of those birds, A. Marshall, told that at the end of June and in July, when it is still winter in Australia, the black males of satin bowerbirds leave their flocks. Each one chooses a place somewhere on a sunlit clearing among the shrubs and builds a bower. Then it brings mainly blue and yellow flowers and other objects, mainly of a blue coloring, similar to its' girlfriend's eyes, and scatters them all before the bower.
Then it colors the bower on the inside.
The bird brings tree coal from somewhere. It 'chews' the coal, adds flesh of some fruit, mixes this paste with saliva and creates a black-colored whitewash. This is used by the bowerbirds all over the insides of the bower. How this happens was describes by Professor Alec Chisholm.
'Many times I found,' he writes, 'bowers, made apparently from burned twigs. One could think that the bird blackened them in a fire beforehand'. But the bowerbird does not do that, but colors them with a coal-paste that it prepares by means described above.
Before beginning this job the bowerbird acquires a piece of soft bark. Filling its beak with the paste it grabs the bark. Slightly opening the beak, and the paste drips from it and onto the bark. The bark serves as a brush: the bird uses it to spread the paste over the bower walls.
But the bower is finally decorated and the male goes into the forest for the female. It does not have to go far, for the female sits somewhere nearby. Before building the bowers the satin bowerbirds form couples and migrate in pairs near the lands where the bowers later will be built.
The bride ceremoniously approaches the bower in order to listen, or rather to look at, the color serenade, for its' cavalier does not sing but plays before the female with various colorful objects. This kaleidoscope of colors captivates the female better than the tenderest of words.
The female enters the bower, or with a stony face stops before it, and the males grabs one colored object after another. It twirls the object in its beak like a crazy dervish. It casts one toy aside, grabs another, growing more and more enthusiastic and bowing and twirling with ever-greater energy. Sometimes it freezes with a beak thrust towards the female, holding some colorful rag that matches the female's plumage or eyes. And the demonstration of the collection begins anew.
From day to day for many months - from June to November or December - the black bird excitedly plays with its colorful toys, often forgetting to eat, to drink, about predators.
If the female, which after two-three weeks is already bored by the bower, departs for the woodland, the male leaves its knickknacks for a moment and calls after the female. It touches the female and it returns. If the female does not return, the male often pursues it, abandoning its bower and all the riches spread before the door.
When a bower is abandoned, the other males, leking nearby, first destroy it, and then steal the colorful collections. They tend to steal even when the owner is present; therefore the owner of each bower chases away all neighbors that visit it. Other females visit as well, but the males doesn't chase them away, but boasts before them of its' riches. Often, for the sake of another, or a single, female it moves the bower to a new place and leks there.
In September - October all of the females leave the bowers and approximately in a hundred meters away from them make the nests on trees, lay eggs and raise chicks. The males do not participate in that at all, but with a former fervor continue to play with toys before their bowers.
They continue to play with them for a long time, until December, as it was said earlier. And later on, when at the end of Australian summer they form flocks, from time to time one or another male will approach the bower where it had so pleasantly spent the time, renovates it and gets new toys. Therefore, some scientists believe that the building, decoration and games before the bower are connected with the birds' breeding only accidentally. The attraction of the females by colorful objects supposedly is not the main designation of these buildings. The main designation is the aesthetic satisfaction that the bowerbirds acquire by decorating their bowers and amusing themselves nearby. Even a special label was offered for this rare instinct - 'proaesthetism'.
However, the experiments undertaken in the British zoo by Dr. Marshall showed that only the sexually mature males, and only when certain hormones were circulating in their blood, build and decorate bowers. The castrated males did not build them or built them poorly, clumsily and soon abandoned them. An injection of hormones immediately added both an interest in the bower and a skill to build it.
Once two black males were caught and carried away from the bowers. The widowed females did not abandon, however, the places of love. Soon both they and the bowers were inherited by young grey-green males, who lose the girlfriends to blue-black dandies without any hesitation.
Thus the bowers also serve, apparently, as a place where new couples are made, if one of the spouses dies or leaves.
The bower is a certain 'secondary sexual symbol of the male, transferred from the living bird to a dead object. Something like a peacock's tail, attractive to the females, made not by nature but by the bird itself. The better-built and decorated bowers and their artful builders are clearly preferred by the females when they are choosing partners for the mating unions. Something similar is being observed among other birds too: the wrens, for example, and possibly the bearded tits, whose females dislike poorly built nests. Here the sexual selection in Darwin's sense occurs in a sufficiently clear form.