Why do female reindeer keep their antlers through winter?

Reindeer (Rangifer tarandus) are unique among all deer species because both males and females grow antlers. While male reindeer typically shed their antlers shortly after the mating season, or rut, in late fall, females retain theirs throughout the winter.123

This adaptation serves a critical survival function: it allows female reindeer to defend access to high-quality food sources, such as reindeer lichen, during the harsh winter months. By using their antlers to protect feeding craters dug into the snow, females can secure the nutrients necessary for their survival and the health of their offspring, effectively competing against other reindeer for limited resources.32