Diversity and number of woodpeckers (Picidae) in the Chuvash Trans-Volga Region in winter

Abstract

This article gives some data on the winter fauna of woodpeckers (Picidae) in the Trans-Volga Region of the Chuvash Republic. We analyze the species richness, their number and trends of its changes. To do it, it is possible when the reserachers analyze the results of the collected materials of 20102018 (on the example of three routes during ornithological surveys according Y.S. Ravkins method). The author believes that the importance of work is to show the lack of surveys concerning the analysis of winter fauna of woodpeckers in the Chuvash Trans-Volga Region. Moreover it shows to determine what impact on the avifauna of the Transvolga was caused by destructive fires in the summer of 2010 (as it destroyed up to 30% of the forest cover of the investigated territory). The article presents that the Chuvash Trans-Volga Region is inhabited by 6 species of woodpeckers out of 9, named in the Chuvash Republic. A great spotted woodpecker was a numerous and dominant species, black woodpecker was ordinary species, and the rest were less common. The greatest variety of woodpeckers was noted on the route with the maximum variety of vegetation and plenty of dead wood. A reliable positive population trend was revealed for the black woodpecker. The population of the great spotted woodpecker as a whole remained stable although it showed considerable fluctuations from year to year, depending on the yield of coniferous trees. For other species, it was not possible to identify any long-term trend. Three species of woodpeckers (the black, the lesser spotted and the three-toed woodpeckers) demonstrated mutual changes of the average winter density. All these species showed a significant increase in numbers, which gave a way to a decline then. We believe that the growth in numbers was due to the fires and drought of 2010, which provoked an outbreak of xylophagous insects and fodder base of these species. The subsequent clearing of the burners and the sanitary cutting reduced the food resources available for insects, what decrease the number of woodpeckers. We believe that sanitary cuttings should be abandoned in some areas of the Trans-Volga Region to preserve these species.