Weather conditions, distribution of resources feed and dynamics of the spatial structure of the Great Cormorant in the water area of Lake Baikal

Abstract

On the basis of long-term observations (2018-2023), the features of the distribution of the Great Cormorant in the water area of Lake Baikal during the mass rise of young birds “on the wing” are considered, depending on the distribution of feed resources and the state of weather conditions. At this time, young birds do not yet have experience of independent food production and parents feed them for 10-15 days. In this regard, the availability and abundance of feed resources is very important for birds. Our observations revealed large, but temporary concentrations of birds in areas of high abundance of feed. Large concentrations of birds are also formed in places convenient for recreation during long periods of adverse weather conditions (from 3-4 to 6-7 days) – strong winds. Such clusters can reach several thousand and even several tens of thousands of birds. They form quickly and also disappear quickly as more favorable conditions are restored on other parts of this lake. This feature of the behavior of birds must be taken into account when carrying out accounting work on large areas, which include snd the water area of Lake Baikal. Accounting of birds from a launch along the coastline, with a detailed survey of colonies in places of their concentration, is the only acceptable method of monitoring the state of the population of the Great Cormorant on Lake Baikal.