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This paper presents the results of a bird census in the Morgi forest range in the Kolbuszowa Forest District (SE Poland). The census was conducted using the point−stand method, i.e. a modification of the point count. This modification enabled tailoring the method to the conditions of the Polish forestry, in which forest stand that is the basic unit of silviculture planning and forest management. The aim of the study was to test the new method of bird census in the managed and large−scale forest units, and to evaluate the utility of the results for conservation measures. Based on the list of stands of the Kolbuszowa Forest District, we drew randomly 270 forest stands, taking into account their most important features: dominant species, forest habitat type, age and vertical structure. Bird counts were carried out in spring of 2014 and 2015. Each stand was inspected twice during each season: 1) between April and mid−May, and 2) between mid−May and the first decade of July. In total, 1080 observation (listening) sessions were conducted and each of the stands was inspected four times. As a result, 14 982 bird observations of 15 757 individuals belonging to 113 pecies were made. In case of 6720 observations, 7186 individuals belonging to 85 species were recorded in the studied stands. The point−stand bird census presented in the paper, which is a forest−range census type, is adequate for use in large−scale forest units. It allows to determine fauna indices that characterise the forest range, together with the most important features of stands.
In spite of environmental uniformity of the European Plains, a conspicuous east-west gradient in the woodland avifauna and breeding bird community composition has been revealed. The species richness in the western woodland avifauna is lower by 32-36% than in the respective eastern samples (n = 120-127 species). Apart from being poorer in species, western communities tend to contain a higher proportion of species which develop dense populations. These features may result from past — mostly postglacial — natural events, from a secondary gradient in the intensity of human impact or from both of them. The data at hand provide evidence for a strong prevalence of the second factor. In view of the mostly anthropogenic character of the differences described, many west-European data can hardly be used as models of the natural patterns in studies of breeding bird ecology. New continent-wide comparative research is necessary to better control for anthropogenic bias in field data. For valid future pan-continental comparisons of bird communities a few large patches of near-pristine woodland should be preserved in the East, as well as restored in the West. Bird ecology studies need also a better co-operation with the archaeozoological and historical research to take into consideration past conditions which could also have influenced the present-day life patterns of European birds.
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