Male moose have antlers, which are not fused to their skull, and their growth is regulated by testosterone. Moose shed their antlers annually, and this process is called casting. Shedding occurs each winter when male moose shed their antlers, and it is a normal annual process for male moose, deer, elk, and other members of the Cervidae family. The primary reason for shedding antlers is to conserve energy for the winter, as antlers can weigh up to 60 pounds on average. Moose shed their antlers after the breeding season, as they are no longer needed for attracting mates or fighting other males. Moose can experience up to a pound of antler growth per day, and antler growth is regulated by testosterone. Moose shed their antlers when the connections between the antlers and the skull weaken, causing them to fall off.