Say, sweet heaven in a tent. Vorobie a different opinion - they are looking for a spouse with a permanent residence permit. But let's start from the beginning.
The majority of birds wakes up very early, and house sparrows take the example of person - I like to sleep. Waking up, they are from the eaves, ventilation pipes flock on the chosen tree to clean the feathers and to outline the programme of the day. After a stormy debate our feathered neighbors fly on business.
Early in the spring of their "working meetings" turn into a brawl: sparrows horohoritsja. each other and not gentlemanly stick to vorobeichik. Their field counterparts behave more sedately - pre pairs. Gradually fights more males fight because of more or less suitable area where you can squeeze the socket. (Most prudent started construction in January!) Having acquired the apartment, the winner comes in even more excitement and frantically squeaking in order to attract the attention of her friends. And those legible and vindictive. They still remember how unbelted throng of admirers chasing them around the yard. And it happens that porobija gets all offer close to the house, before bestow his favor of the owner liked the apartment. Him thus overlap all bird marital rights and obligations. Once established, porobija becomes rough mistress. And if during the absence of the head of the family nest gonna neighbor, even the most respected, it will fly down and feathers.
A. I. Ilchenko interesting in the book "Ecology of house sparrows and their ectoparasites" writes that Moscow sparrows housing is often constructed spouse: Sparrow transported to the construction of straw, grass, thread, wool, paper, and borobia from all of this builds walls.
When installing housing, caring for offspring, sparrows hardly think about the aggressors. And those here. It's Swifts. In scientific works dispassionately described the bloody battle: Swifts without a moment's hesitation kick out of the nest helpless nestlings or beating eggs. Protecting home and family, males sometimes fight till the last breath.
Early spring is changing not only the behavior of birds in winter they mostly gregarious way of life), the major physiological changes occur in their frail little bodies. Alters the color of the bill, the size of the testes increases in 1127 times - they now weigh 5% of the whole body! This increase them very suitable in winter does not have to carry the extra weight. (Sparrow weighs about thirty grams, and one third of the weight falls on the chest muscles, lowering the wing in flight.) Before laying eggs in the blood of vorobie accumulate lime substances (calcium heavily consumed from the outside) is the basis of the future shell. As soon as the temperature will rise to 6 to 10 degrees, will be demolished first egg.
Offspring in the nest usually 4-6, and they all open beaks, all you need to feed. And late, those who bad mouth raceway, children do not recognize and even thrown out of the nest. This cruelty is not meaningless - deliverance from Hilo offspring has good biological status of the population.
During the first week of life, the Chicks are heavy in five or six times. Their daily need for protein - tenth of its weight! If this is translated into human measurements, the breast the baby needs to eat per day for several kebabs. And here's the strange thing - the sparrows, being mainly granivorous, feed their children insects. For this oddity we have them in the legs to worship: a day in the nest forever disappear around a thousand insects, of which 800 pests. But even in the middle lane sparrows three times in the spring and summer season are taken to lay eggs.
Sparrows prolific. Yes they have no choice - we need to confront adversity and the number and skill. And difficulties with each passing year more: panel building, where you will not find a place to nest with all the resourcefulness and steel bins on garbage cans, cutting access to food. And disease? And cats? And cars? These growling machines have long been ousted from the city streets of horses and thereby caused the sparrows irreparable damage: railway vehicles from the exhaust digested grain oats do not fall... one way or another, until the fall of reach only half of the Chicks. Alas, life expectancy Sparrow - 9 months. Experienced reach 21 months. In General passerine considerable age - 14-15 years old.
In the cities now not that horse, but the caterpillar or spider difficult to find. And so the parents have even the most small children in addition to beetles and flies to invest in open beaks bread, peanuts, sunflowers... one wrobleski-juvenile caught in Moscow, goiter was filled with lime. Not from whether such power is so great mortality passerine nestlings in large cities? Is it because it caught birdy-albinos, which by quite a few gray feathers?
But enough of regrets because sparrows do not groan and not Achaia, and chirp.