Peculiar traits of nest constructions of the common crane Grus grus in the context of diversity of nests of Palearctic cranes

Classification of nest constructions and parameters of their unified measurements are proposed on the basis of 35-year observations of nesting cranes in various regions of the former USSR and modern Ukraine (447 Grus nests and 111 Anthropoides nests). This classification allows comparing the measurements of the nests of the same types and usage of the frequencies of the various types of nests for comparison of the settlements in different locations of breeding ranges. Two types of nest constructions were distinguished for seven species of Palearctic cranes: 1) Anthropoides -like, or “the nest on the tree stem base” (99.5% of demoiselle cranes Anthropoides virgo, 85.0% of the lesser sandhill cranes Grus c. canadensis, 10.0 to 15.0% of steppe common cranes G. g. grus on the left bank of the Dnieper River in Ukraine); and 2) Grus -like, or “the nest on the water” (0.5% of demoiselle cranes, 10.0 to 15.0% of the lesser sandhill cranes, 59.0 to 71.0% of steppe common cranes in Left-bank Ukraine, all red-crowned cranes G. japonensis montignesia, white-naped cranes G. vipio, hooded cranes G. monacha, and Siberian cranes G. leucogeranus).