Birds Of Tropical Africa

 

BIRDS form a very large class of the Animal Kingdom. Like the mammals they are warm-blooded and possess an inside skeleton. They are, however, unlike the mammals in that they have feathers instead of hair; their fore limbs are specially shaped (adapted) for flying; and the hind limbs are used for swimming or running. Birds possess no teeth, but instead they have a "beak" or "bill" with which they peck at their food instead of chewing it like a toothed animal. The feet and lower parts of their legs are covered with scales like a reptile. All birds produce their young by laying eggs. These eggs are cared for and tended by the parent birds, and the young eventually hatch out. In most cases the young have to be fed and looked after by the parents for some time after they hatch out. Birds are of great interest to man. They are particularly useful on the one hand as destroyers of harmful insects; in many cases if there were no birds certain species of insects would be a grave danger not only to crops and to other animals but to the existence of man himself On the other hand, a few birds do damage to certain crops by eating grain, fruit, or the young buds and tender growing parts of the plants. The song of birds as a rule seems to be an expression of joy; all birds do not have this power of song, but most can at least attract attention to themselves by their calls.

To produce their young, birds generally build nests in which to lay their eggs. As stated above these eggs are very carefully watched by the parents, and after hatching, the young fledglings are regularly fed and sheltered until they are old enough to fend for them-selves. Most birds migrate; that is to say, at certain times of the year they collect together and travel for great distances in order to avoid extremes of climate, or to collect food, or for other purposes. hi some cases migration may simply be from the sea-shore inland for a season, or perhaps from valleys to mountains; but in many cases migration is over distances of many thousands of miles, and some migrations take place through a long period of years.

Probably the best-known migratory bird is the swallow, which spends the summer in England and in Northern Europe, where the nests are built and the young are hatched out In the winter, when the weather begins to get too cold, and there is not so much food, the swallows all congregate together and fly off to spend the winter in Africa, where it is so much warmer. By catching birds and marking them, we have been able to find out sometimes the distances they travel Thus a swift caught in Zaria a few years ago had a small ring on one of its feet, which had been put on in Germany the previous summer.

The reason for migration is mainly the search for food; but how birds accomplish their immense journeys by night and day and over the sea with nothing to guide them has not yet been discovered. Some birds live together in social communities One of the most typical of these in West Africa is the weaver bird. One sees weaver birds' nests commonly hanging in considerable numbers from the bare ends of branches of trees, and particularly from the tips of old palm branches. One would ordinarily think that this was a very unsuitable place for their nests, as it is exposed to the wind and rains, and also can so very easily be seen by the birds' enemies. But this is really not so unsuitable as it would at first appear. In the first place, the nest is completely covered in; it is constructed of closely and firmly woven grass, and hanging

 

down from it is a tunnel also of strongly woven grass; the entrance to the nest is at the bottom of this tunnel The whole nest hangs from near the tips of the branches of the tree held only by a fine but strong string of fibers.

The enemies of these birds are cats, rats, snakes, etc., birds of prey, wind, rain and exposure. Against all these their nests protect them. Cats cannot climb out on to the fine twigs to which the nest is attached, and so the birds and eggs are safe from them; the same applies to rats, snakes, etc. And at the best these would only secure a very dangerous foothold and at the same time would be attacked by the birds. Birds of prey cannot make a sudden dash and snatch away the eggs or young as they are hidden in the middle of the strongly woven nest.

They could, of course, with their strong claws and beak, soon tear the nest to pieces; but this they find difficult to do as the nest swings about on its fine ~ almost swaying them off, and at the same time they are attacked by the whole crowd of weaver birds who live to-her for this common purpose of protection During storms the nest swings about and the tips of the branches bend to the wind, and in so doing prevent great strain being put on the nest The nest itself is so well woven that even in heavy storms the rain tends to flow down the outside, and it is seldom that the eggs or sitting birds get very wet In this way, in spite of the fact that these nests are very much exposed and easily seen by all enemies, the weaver birds' colonies are comparatively safe and secure.

Weaver birds feed generally on seeds, fruits, corn, etc., but also eat insects. As their main food is seeds, they require to have powerful bills, whereas birds that are entirely insect-eaters do not have strong bills. The crows .belong to the same great family as the weaver birds; and like them live together in social colonies. Crows are probably the wisest of all birds, and seem at times to possess powers of reasoning. Crows will feed on almost anything seeds, flesh, insects, young plants, etc. When feeding they often collect in great flocks, and have "sentries", or guards posted at several points to give them ample wash of the approach of an enemy. They are often great thieves, and not content with stealing food, they will sometimes steal beads, jewellery, pieces of metal, and, indeed, almost anything white and shiny.

To their enemies they are very savage, and often attack them with great ferocity; in this way they prevent snakes, rats, etc., from getting to their nests or eggs. At the same time, however, they will assist any of their own kind in distress or danger. Crows do much good as well as a certain amount of harm; they eat many harmful things like garbage and refuse; on the whole they are much more man's friend than his enemy. Many of the smaller bird - robins, swallows, wag-tails, pipits, night-jars, swifts, etc.---feed entirely On insects, and must do an inestimable amount of good. The bronze-winged "crow-pheasant", or bush-pheasant, or bush-crow, is not really a crow at all but belongs to the cuckoo family.

Among the more common water birds in Africa are ducks, herons, storks, flamingoes, and egrets. In the ease of the duck the toes of the feet are joined together by a thin skin to assist this bird when swimming; this feature is characteristic of many water birds and they are accordingly said to be web footed. Storks, egrets, etc., frequent shallower waters than the ducks, and do not swim but wade about, looking for food in the shape of frogs, snails, water leeches, etc. For this reason the stork and heron families have developed long legs and long bills. In this and many other ways, birds, as in the ease of all other living organisms, are specially adapted to suit their own habits and mode of life.

Birds taken as a whole are of considerable assistance to man, for not only do they play an important part in destroying harmful insects, but their beauty of color, the beauty and joyousness of their song, and their activity are a source of great pleasure. In some cases birds assist in pollinating flowers, and in the distribution of seed.