Moose are among the largest and most recognizable animals in North America. A common question about these creatures concerns their antlers, specifically whether both male and female moose possess these prominent bony structures.
Antlers on Female Moose
Female moose, known as cows, generally do not grow antlers. Antlers are primarily a characteristic of male moose, or bulls. However, in extremely rare instances, a female moose might develop small, sometimes malformed, antlers. This unusual occurrence is linked to hormonal imbalances, such as elevated testosterone levels, often due to ovarian abnormalities or tumors. Such cases are considered abnormal and are not representative of the species’ typical biology.
The Purpose of Male Antlers
Male moose grow antlers annually, primarily for use during the rut, or mating season, which occurs from September to October. These large bony structures, which can weigh up to 40 pounds and span up to six feet wide, are used in displays of dominance and in combat to establish mating rights. Bulls will often use their antlers to intimidate rivals, and if intimidation is insufficient, they may engage in sparring matches, locking antlers to prove their strength and secure access to females. Antlers also offer a form of defense against predators, though their primary function is intra-species competition.
Antlers are shed each year, usually between November and January, after the mating season concludes. New antlers begin to grow in the spring, covered by a soft, fuzzy skin called velvet, which supplies blood and nutrients for rapid growth. This growth can be remarkably fast, sometimes exceeding an inch per day. By late summer or early fall, the velvet dries and is rubbed off, revealing the hardened bone underneath, ready for the upcoming rut.
Distinguishing Moose
When antlers are not present, distinguishing male and female moose requires observing other physical characteristics. Male moose are generally larger and heavier than females, with bulls weighing between 794 to 1,323 pounds, while cows typically range from 595 to 882 pounds. Males also tend to have a more robust, muscular neck and a pronounced shoulder hump.
Both sexes possess a dewlap, a fleshy flap of skin hanging beneath the chin, though it is usually larger and more prominent in males. Females may have visible udders, particularly if nursing a calf. Additionally, female moose often have a light-colored vulva patch beneath their tail, which is absent in males.