Biological features of the black crow

For a long time, an interesting and very familiar bird, the crow, has lived next to humans. What is she really like? Why does a person sometimes declare war on her? Why love her? Not long ago, hunters who exterminated crows were paid bonuses. Is this the case everywhere? How can a crow influence other animals, what is its role in the lives of other birds and people? It is interesting to watch birds and we have noticed that in the last two years there have been more corvids in our village. We decided to pay attention and solve interesting problems.

Folk wisdom noted such biological characteristics of corvids as intelligence, caution, mutual assistance.

The scientific biological characteristics of the black crow are as follows: it is a medium-sized bird with a dense build. The large head bears a strong, slightly laterally compressed beak. The length of the beak is less than 55 mm, it is less than the length of the head. The bristles covering the nostrils also cover the crest of the main part of the beak. Beak height less than 21 mm. Wing length less than 370 mm. The length of the lantern is less than 64 mm. Tail with straight or slightly convex rear edge. The primary flight feathers are not pointed. The end of the beak is noticeably bent downwards. The base of the beak is covered with feathers. The color is black with a blue or purple metallic tint.

The crow is an ordinary sedentary bird, distributed everywhere, inhabiting forest landscapes. Birds spend the winter near human habitation, accumulating in landfills, where they feed on various food waste.

All corvids have loud, often dissonant voices; many can perfectly imitate the voices of other birds; some learn to pronounce individual words in captivity. In general, in terms of their mental abilities, corvids leave behind all other birds. These are the most “smart” birds, which is especially evident when kept in captivity.

How many stories and fables are told about the raven. In them she is sometimes stupid and gullible, sometimes fantastically smart, cunning and resourceful, sometimes sinister and cruel. What is she really like?

Successfully finding food in an uncertain world requires certain skills. An example of good adaptability is the crows that live in western Canada: some of them have learned to pull shellfish out of the water at low tide.

Experiments show that crows pick up only those shells that, judging by their weight, should contain a living mollusk. It seems as if the birds know that the light shell contains only the remains of the animal. To remove a mollusk from a shell, crows break it against stones. On average, they have to throw the shell 4 times from a height of 3 - 8 m. It might be more effective to throw the shell from a great height, but in this case its contents often end up scattered or dirty in the sand; Choosing the right height is very important and must be learned.

Our Russian crows are no more stupid than Canadian ones! Interesting pictures of the life of crows can be seen here too. This is what we saw: the silence of the day was suddenly disturbed by a terrible roar. Fuck-daba-dah! There are no people or tracks on the roof. A crow was sitting under the window and was trying hard to either split or peck something. Apparently, she was not very successful at this, since she walked around more than she rattled on her subject. The sound was not the same at all. Suddenly the crow grabbed a tin can, with difficulty tearing itself away from the roof, flapping its wings heavily, reached the top and released it from its beak. The empty jar, loudly hitting the roof, rolled down with a noise, leaving behind, apparently, something tasty, because the crow, immediately picking everything up, began to fuss around it again.

Another interesting incident was told to us by our school teacher L.V. Raevskaya. From the window of her house you can see the railway track. You can often see several crows there; they fly not only in search of food, but also to have fun. Crows can be seen every day, but the most interesting thing is to watch them. After finding leftover food waste and eating, the crows organize “sports competitions.”

In our village, a lot of snow falls in winter, the railway track is located much higher than the level of residential buildings, and when snow removal machines rake snow from the track, snow slides are formed. On a clear sunny day, crows ride down hills, trying to get ahead of each other. At the same time, each one, making noise, “croaking,” and pushing, tries to rush up the hill faster. Po-e-ha-li!

We can say that crows are no strangers to the love of games. A variety of crow games are available for observation by any resident of our village. An example: two or three crows are flying at different heights, and one of them, flying higher than the others, deliberately releases a branch from its beak. The crow of the “second floor” picks up the branch and changes roles with the first one. If the second crow misses, the crow on the “third floor” will actively come into play.

Memory and learning

In their natural environment, birds exhibit remarkable memory. Crows remember food hidden by themselves or in front of their eyes for several hours.

Raven can even be taught to count, although not more than ten. They managed to train the raven so that from piles containing a lot of grains, she always ate a certain amount - 1,2,3,4 or 5 pieces. They placed boxes next to each other, in which they placed one or two grains. The crow opened the boxes until it ate the required amount of grains.

The art of imitation

By imitating and innovating, birds acquire habits and calls characteristic of their species.

At first glance, all crows caw the same way, but scientists have proven that there are different “accents.” The cawing of French crows is different from the cawing of English crows. Crows acquire accents in the same way as humans when they move into areas with a strong local accent.

For crows, this scheme can work in the opposite direction: a group of birds arriving in a new area can influence their neighbors and change the existing local sound of cawing, bringing it closer to their own.

Watching the crow and studying the collected material, you just want to exclaim: “But the crow - oh, not an ordinary bird!”

“Missed” - they say about a mouthless person, “a raven is counting” - they say about an absent-minded one, comparing it with a crow. It's not true, the crow is a wonderful bird!

Any species is a large population and in turn consists of smaller populations, since the species is not uniformly distributed in space.

We conducted our observations of the black crow population in our village. At the appointed time, the density of black crows was simultaneously observed in different parts of our locality. Density is the number of individuals per unit of space.

Observations led to the conclusion: the largest population of black crows is constantly located in the landfill, small populations move around the territory in search of food, sticking to places with food waste discarded by humans.

I wanted to pay special attention to the crow’s nutrition!

The crow is an omnivorous bird. Its food consists of locusts, large beetles, mollusks, small rodents, lizards, frogs, and fish. By destroying carrion, harmful insects and rodents, they bring significant benefits. You can call a crow a good "orderly". But we were interested in another aspect of the crow’s habitat in our village and its effect on domestic animals.

On March 3, 2006, the newspaper “Baikal Lights” published an article by P. Sukhanov, chief state veterinarian of the Kabansky region: “Caution: bird flu!” The article indicated registered facts of avian influenza epizootic. (An epizootic is a widespread spread of some infectious disease among animals.)

“The disease was recorded among wild and poultry. Influenza disease usually occurs when poultry comes into contact with wild birds infected with the influenza virus, when poultry is fed infected feed and through bedding material.

To avoid outbreaks of influenza among poultry, you should not walk them near places where wild and synanthropic birds (pigeons, sparrows, etc.) gather, but it is better to keep them in enclosed spaces and courtyards. Feed and bedding material should be stored in a room that excludes the entry of wild and synanthropic birds."

Perhaps the black crow is a carrier of the avian influenza virus - Sinanthropus, since birds move very actively, members of the same population are neighbors forced to jointly develop the territory they occupy and reproduce on it, so they have a lot in common in adaptive features and varying degrees of interactions arise. Our observations allow us to conclude that during unfavorable periods, individuals of black crows accumulate and survive the winter together, and constantly stay near humans. Within a population, individuals unite in flocks, where they perform joint actions - defense, migration, obtaining food.

No matter how well we treat our “Karkusha”, such a version still arises.