The Effects of Weather and Climate Changes on the Timing of Autumn Migration of the Common Crane (Grus grus) in the North of Moscow Region

A significant correlation between the beginning of the formation of migratory congregation and the ultimate transition of minimal daily temperatures below 10 degrees C was revealed (r(s) = 0.52, p < 0.02). Departure of common cranes from the north of Moscow Region usually occurs between September 15 and October 15, on 28.09 +/- 5 days on average. A significant trend for the shift of this event to later dates (r(s) = 0.66, p < 0.002) was apparent from the data collected during 19 years (in 1994-2012). The date of departure of the cranes is affected by the ultimate transition of minimal daily temperature below 0 degrees C (r(s) = 0.64, p < 0.003), the abundance of precipitation (r(s) = 0.49, p < 0.03), and the number of days with precipitation (r(s) - 0.51, p - 0.026). Cranes stayed at the migratory autumn stopover for longer periods during rainy seasons.