The intraannual dynamics of ornithocomplexes of the Central Altai middle-mountains.

For revealing seasonal and intraseasonal dynamics of bird communities in the Central Altai middle-mountains there was conducted a cluster analysis of the dates collected inUst-Koksa (Altai Republic) on constant routes in seven biotopes from December 1998 till November 1999. The estimation of intraannual dynamics ornithocomplexes was carried out on matrixes of P. Zhakkar coefficients of similarity with modifications for the quantitative characteristics calculated for each of seven biotopes on 24 variants and based on not metric scaling methods. The analysis of bird communities of separate biotopes, as well as on average on the territory, according to seasonal periods revealed earlier has shown that the greatest total abundance of birds, species and background richness of birds are typical of the period of nesting on the background of termination of arrival, flight and local movings; the least - for the period of winter stabilization. The distinction of indexes of these periods, on average, amounts the abundance in total up to 17 times. The number of all encountered and background species during these periods differs up to 8-18 times. Prevailing species coincide only partially (by yearlong round meeting species). The spring and autumn periods differ in total indexes too, but it is less than in summer and in winter. Despite close enough or slightly different total indexes values of ornithocomplexes (abundance, species and background riches) in spring and autumn periods, the structure of their communities is rather distinguished, as the ornithocomplexes analysis showed by means of similarity factors and revealing a yearlong round dynamics of bird communities on their basis.The configuration of a year cycle curve of ornithocomplexes changes of all surveyed forest biotopes has the form close to a circle that, in a general view, reflects small similarity of both summer and winter, and spring and autumn variants of bird communities among themselves. Bird communities' changes of open biotopes are presented in the form of a circle with a wedge of variants of the communities of a warm season, which is connected with occurrence in the spring and disappearance of flying and enough numerous species by the end of summer or in early autumn. Changes in the rest of a year are gradual. Ornithocomplexes dynamics of villages and rivers is a special case before the considered type, where different variants are presented in the form of a «chain» of deviations from a circle that is defined by the intensity of spring-and-summer migrations (in villages) or by the presence of a wintering species - dipper water ouzel in rivers (from the middle of October till the middle of March). Thus, a combination of snow cover bedding fragmentariness, constant presence of forages, including that of an anthropogenous origin, and the arrangement of the surveyed mountain hollow away from the basic ways of migrations predetermine a year cycle of bird communities changes of the surveyed biotopes much closer to a circle, than in other surveyed regions.

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