Moose are the largest members of the deer family, captivating observers with their imposing size and distinctive appearance. Found in the northern forests of North America, Europe, and Asia, these majestic animals possess unique headgear. A common question concerns which moose possess these prominent features.
Moose and Antlers: The General Rule
Generally, female moose, known as cows, do not grow antlers. The impressive, broad, and palmate antlers characteristic of the species are a feature of the male moose, or bulls. These bony structures can reach spans of up to 6 feet across and weigh as much as 40 pounds in mature individuals, making them the largest antlers among all deer species. Unlike horns, which are permanent, moose antlers are shed and regrown annually.
Why Males Grow Antlers
Antlers serve several important biological purposes for male moose, primarily linked to reproduction and social behavior. During the autumn mating season, known as the rut, bulls use their antlers to establish dominance and compete for access to females. The size and condition of a bull’s antlers signal its health and genetic fitness, influencing its success in attracting mates. Clashes between bulls can involve locking antlers in battles to assert their strength and claim mating rights.
Antlers begin growing in the spring, covered in a vascularized skin called velvet, which supplies blood for rapid bone development. By late summer or early fall, the velvet is shed, leaving the hardened bone ready for the rut. After the mating season concludes, typically in late winter or early spring, the antlers are shed due to hormonal changes, conserving energy for the colder months.
Unusual Antler Growth in Females
While rare, female moose can develop antlers. This unusual phenomenon is typically linked to hormonal imbalances, specifically increased testosterone levels, which can be caused by ovarian abnormalities like cysts or tumors, or issues affecting the adrenal glands. These antlers are often smaller, less branched, and sometimes malformed compared to those of healthy males. They may also remain in velvet, a condition known as “velvet-antlered” or “peruke head,” and might not shed annually. This highlights the significant role hormones play in the physical characteristics of these animals.