Scientists need to figure out how much bird populations have declined
In Moscow, as well as throughout Russia, a census of the feathered population has been announced. But not all in a row, but only those whose noticeable reduction in courtyards and squares has caused noticeable anxiety among residents in recent years — sparrows. According to ornithologists from the Union for the Protection of Birds of Russia, these nimble birds are really getting smaller. The population of the house sparrow suffers especially, the number of which in many surveyed regions of our country has declined catastrophically. The MK correspondent found out what this could be connected with and how, in fact, these sparrows should be counted.
The census started across the country on March 20, International Sparrow Day, which has been celebrated since 2010. According to scientists, we most often sound the alarm on rare, exotic species of birds, and we often forget about the most common ones, which even winter in cities with us. It was believed that these nimble sparrows will always take their toll, it never even occurred to anyone that this species could be vulnerable.
The Union for the Protection of Birds told us the reasons why the number of sparrows in megacities may decrease. This ubiquitous «rolling up» streets into asphalt, mowing lawns until seeds ripen on them, introducing closed-type garbage cans in cities, treating green spaces from insects that birds feed their chicks with, cell towers, etc. A more accurate answer can only be given after a more in-depth study.< /p>
In his article on sparrow «demography» In 1987, ornithologist Valery Ilyichev pointed out that “the average density of house sparrows in winter in residential areas of the center of Moscow was 1–6 thousand individuals per 1 sq. km. km, in the central parks — 360 individuals per 1 square. km". The number of the field sparrow, which, as a rule, lives in the central parks of the capital, was 222 individuals per 1 sq. km. km.
More than 20 years after Ilyichev's count, sparrows were counted again — this was needed for the Atlas of Moscow Birds, which was released in 2014. The recorded maximum density of the house sparrow in it was already determined at 500 individuals per 1 sq. km. km, while in many areas it was noticeably lower.
The maximum density of the field sparrow, calculated from the atlas database, was 175 individuals per 1 sq. km. km (with an average density in all territories of 25 & ndash; 30 individuals per 1 sq. km).
— The methods of Ilyichev and the authors of the atlas, of course, could differ, — explained to us at the Zoom Museum of Moscow State University, — but not the fact that it is significant.
According to the press secretary of the Zoom Museum Olga Ryabova, such calculations were no longer carried out from 2014 to 2023.
However, employees of the Zoological Museum of Moscow State University and the Center for Wildlife Conservation note that now, according to their observations, a sharp decrease in the number of sparrows — both typical urbanists, brownies, and their brothers, field, — no longer occurs in the metropolis. This conclusion was made approximately, scientists are still monitoring.
With the count of birds, the townspeople who are not indifferent to birds were called to help.
To begin with, they will have to go through a small biological educational program. First, you need to learn to distinguish between different types of sparrows. We are lucky — of seven different species living in Russia: brownie, field, black-breasted (Caucasus and Crimea), stone (Caucasus, Altai), Mongolian earth (Altai), snow (Caucasus, Altai) and red (Sakhalin Island) sparrows, in Moscow only the first two types are the most common. They differ easily: the field sparrow — it is a bird with a completely brown cap on its head. Distinctive feature — bright white cheeks and black spots on them. Male and female tree sparrows are exactly the same.
In the house sparrow, males and females are colored differently. Males are bright, with a brown-gray head. Pay attention — the top of their head is gray, their cheeks are white, without any spots. Females are dimly colored, do not have bright tones in their plumage.
So, one of the days, until March 26 inclusive, we go outside and walk around the neighborhood of our house or school with a notebook. House and field sparrows should be counted separately. It is easy to fix flocks of brownies or field near the feeders, if there are none, you can look for «sparrow bushes»; — places where they gather to rest.
How to fix sparrows.
For each «sparrow bush»; it is important to determine its address or coordinates, which are entered in a separate questionnaire on the eurobirdwatch.ru website. It also indicates: the type of development (high-rise, low-rise rural, no development — park, etc.); the number of house and field sparrows, surname, name and patronymic of the «accounter». By the way, each assistant to ornithologists will also be issued a certificate of participation in the census «Sparrows in the bushes», — it can be downloaded in your account after April 1. Well, let's go to drive, that is, to count spring sparrows?