Antlers are the most memorable characteristic of reindeer. In males, antlers can measure 20 to 51 inches (52 to 130 centimeters) long, and females’ antlers can reach 9 to 20 inches (23 to 50 centimeters). Unlike horns, antlers fall off and grow back larger every year. While the new antlers grow, the reindeer is said to be in velvet, because skin, blood vessels, and soft fur cover the developing antlers.
Males begin to grow antlers in February and females in May. They both finish growing their antlers at the same time and shed or rub off the velvet during September. However, they shed their antlers at different times of the year. A male drops his during November, leaving him without antlers in December, while female reindeer keep their antlers through the winter until their calves are born in May. This fact has led many to believe that, based on the presence of antlers, Rudolph the red-nosed reindeer must have been a female to have those antlers on Christmas Eve!
But what are the antlers for? They are handy weapons against predators, and males use their impressive antlers (which can weigh up to 33 pounds, or 15 kilograms!) to impress the females.