Elk are known for the impressive bony structures that grow from the heads of males. These structures, called antlers, are not permanent fixtures. Male elk undergo an annual process of shedding and regrowing their antlers. This yearly regeneration allows for the development of new, often larger, antlers.
The Annual Cycle of Antler Shedding
Elk shed their antlers due to hormonal changes, particularly a decrease in testosterone levels after the breeding season, known as the rut. This hormonal shift weakens the connection between the antlers and the skull. Shedding generally occurs from late winter to early spring.
An elk’s age, overall health, and geographical location can influence the exact shedding period. For example, older, healthier bulls may shed earlier, as might elk in warmer climates compared to colder regions. This annual process taxes their energy and calcium reserves.
From Shedding to Regrowth
The shedding process begins when an abscission layer forms at the base of the antler, where it connects to the skull. This layer weakens the bone connection, allowing the antler to detach. Shedding is not painful for the elk and can happen quickly.
Soon after shedding, new antler growth begins, making antlers one of the fastest-growing tissues in the animal kingdom. During this rapid growth, the developing antlers are covered by a soft, furry skin called velvet. This velvet is rich in blood vessels and nerves, supplying nutrients and oxygen for the growing bone. Elk antlers can grow rapidly, sometimes over an inch per day. Once fully grown and hardened, typically by late summer, the velvet dries, cracks, and is rubbed off by the elk on trees and shrubs.
Antlers Versus Horns
Antlers and horns are distinct biological structures, though often confused. Antlers are made entirely of bone and are shed and regrown annually, a characteristic found primarily in male members of the deer family (Cervidae), including elk, deer, and moose. Caribou are a notable exception, as both males and females typically grow antlers. Antlers grow from their tips, with size and branching patterns varying by age and species.
In contrast, horns are permanent structures composed of a bony core covered by a keratin sheath, similar to human fingernails. Horns are never shed and continue to grow throughout an animal’s life. Animals like cattle, sheep, goats, and bison possess horns. Antlers serve various purposes for elk, including display, defense, and competition for mates during the breeding season. Larger antlers can signal health and strength, making males more attractive to females and more formidable to rivals.
Ecological Role of Shed Antlers
Shed elk antlers play an important role within their ecosystem. Once shed, these bony structures become a valuable source of essential minerals, particularly calcium and phosphorus, for other animals. Rodents like mice, squirrels, and porcupines, along with bears and foxes, often gnaw on shed antlers to obtain these nutrients and to wear down their continuously growing teeth.
The presence of shed antlers can also provide insights for wildlife biologists studying elk populations, offering clues about their health and distribution. Humans engage in “shed hunting,” collecting these discarded antlers as a recreational activity. Regulations often exist to manage shed hunting to minimize disturbance to wildlife, especially during sensitive periods like late winter when elk are vulnerable.