structural:expansion, structural:summarization
Coat

European red deer tend to be reddish-brown in their summer coats, and some individuals may have a few spots on the backs of their summer coats. During the autumn, all red deer subspecies grow thicker coats of hair, which helps to insulate them during the winter. Autumn is also when some of the stags grow their neck manes. The autumn/winter coats of most subspecies are most distinct. The Caspian red deer's winter coat is greyer and has a larger and more distinguished light rump-patch (like wapiti and some central Asian red deer) compared with the Western European red deer, which has more of a greyish-brown coat with a darker yellowish rump patch in the winter.

By the time summer begins, the heavy winter coat has been shed; the animals are known to rub against trees and other objects to help remove hair from their bodies. Red deer have different colouration based on the seasons and types of habitats, with grey or lighter colouration prevalent in the winter and more reddish and darker coat colouration in the summer.