Changes in the migratory characteristics of some species of the Crimean avifauna under conditions of climate warming
Global warming is a factor that has significantly affected the migratory characteristics of birds in recent decades, which has already been revealed for a number of regions of the Northern Black Sea region. The purpose of this paper is to record changes in the nature and duration of stay of some migratory and wintering birds in Crimea under conditions of changing climatic situation. Observations were carried out in different regions of the Crimean Peninsula from 1981 to the beginning of 2022. A significant part of data was collected in the anomalously warm autumn-winter season in 2020/2021. Substantial changes in these characteristics were registered for 24 bird species. An increase in the duration of migration periods was recorded for 13 species, including 12 species in autumn, due to the later end of migration, and 4 species in spring, due to its earlier start. Over the past 40 years, fifteen species have been first found wintering in Crimea (Pelecanus onocrotalus, Egretta garzetta, Ardea purpurea, Ciconia ciconia, Himantopus himantopus, Recurvirostra avosetta, Pluvialis squatarola, Charadrius hiaticula, Ch. alexandrinus, Tringa totanus, Arenaria interpres, Chlidonias leucopterus, Upupa epops, Ficedula parva, Phylloscopus collybita); four more species (Grus grus, Larus genei, Alcedo atthis, Motacilla alba) known until 1980 only from rare or single observations. Moreover, the authors recorded more numerous winter aggregations than previously for three species while seven species were registered for the first time wintering in the mountainous part of Crimea. Thus, the results obtained indicate the following changes in the migratory characteristics of birds: an increase in the duration of the migration period due to a shift in the timing of the beginning of spring and the end of autumn migration towards a colder season of the year; the appearance of wintering bird species that were previously uncharacteristic for this period in Crimea; in some cases, an increase in abundance of wintering birds as well as expansion of wintering areas