In the world there are at least 8600 differentspecies of birds, of them in the territory of our country - more than 700 species. In the forests, gardens and parks of the European part of the territory there are 294 species. Different species of birds of Russia find shelter both in forests and in urban conditions.
In our country with its harsh climate, many speciesbirds fly to warmer countries for the winter, and those who remain often wander from the north to the central and southern regions. In severe frosts and because of the cold and lack of food, birds often die in large quantities.
The need for birds in food is very high due togreat mobility and intensive metabolism. The daily volume of feed is about one-fourth of the body weight. Birds of prey eat once a day, grains - at least two, and insectivores - about 5-6 times. During the growth of chicks, the need for food is even greater. They grow very quickly, during the week the weight of the newborn increases several times.
Forest birds of Russia make up the mosta large group of species. Birds are real friends and saviors of the forest from harmful insects. Some of the species are exclusively insectivorous (goat, nuthatch, almost all kinds of songbirds). In others (tits, starlings, shrike) insects make up the predominant part of the diet. Cereals and omnivores include crows, oatmeal, bullfinches, jackdaws, finches, woodpeckers and sparrows. But they also nurture chicks only by insects. And with a strong multiplication of insect pests, all birds, even grains, feed exclusively on them.
Forest birds differ not only in characterration, but also a kind of nesting. In the hollows nest about 10 species of insectivorous birds and 10 species feeding on small rodents. The rest of the small nest on the ground and in the bushes. The thick undergrowth for them is the best habitat and reliable protection from enemies. That is why in the old forests where there is no undergrowth, there are few birds.
Finches on the fringes of forests, in gardens and parksand the cuckoo, the nightingales set nests in the bushes of bird cherry and elderberry along the forest streams and rivers, the tits love the forest thicket, oatmeal and chamois choose small shrubs or thick grass in glades and felling areas.
Forest birds help the forest to grow. From the seeds scattered with their droppings, new bushes grow. Many birds (woodpeckers, jays, starlings, tits) hide seeds of trees, acorns, nuts in moss or old stumps. From such forgotten or not completely selected "hiding places" new trees are then sprouting. Crows, magpies and jackdaws spread the seeds of garden plants, which can therefore be found in the forest in unexpected places.
Forest birds have many enemies. Especially a lot of birds die during the hatching of eggs and feeding of chicks, when parents can not leave the nest and become especially vulnerable. Because of predators, and also from human hands, no more than a tenth of small birds survive in the forests near populated areas. In parks and gardens this percentage is even lower.
The most serious enemies of birds (especially those livingnear cities) - domestic cats. Far away from residential areas, flyers are hunted by foxes, ferrets, martens, caresses, ermines. For nesting on the ground birds are hedgehogs and shrews. People also do a lot of harm to birds by deforestation and spraying of pesticides. Thus, only a few forest birds live the entire life-span of nature. And it is quite long: for jackdaws - 11 years, for starlings - 10, for thrushes, wagtails and rides - over 10, for swallows and swifts - about 9, for finches - 7 years. Many birds are able to live even longer - sparrows under 18 years, river gulls about 20, magpies - 21 years, nightingales - 25.
When flying to distant lands birds are capable ofdevelop a significant speed. Thus, small birds fly at a speed of 30 to 50 km / h, starlings from 60 to 79 km / h, waders - 55 to 86. Predatory birds (peregrine falcon) fly at a speed of 95 km / h, and when attacking prey - about 360 km / h.
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