Moose, the largest members of the deer family, are instantly recognizable by their impressive antlers. These unique bony structures are a defining characteristic, often sparking curiosity about their life cycle and whether these adornments are a permanent feature.
The Annual Antler Cycle: Growth and Shedding
Moose antlers are regrown each year. Unlike horns, which are permanent bony outgrowths covered in keratin, antlers are solid bone structures that are shed and regrown annually. This process begins shortly after the previous year’s antlers are shed, typically in early spring.
Antlers grow from bony protrusions on the moose’s skull called pedicles. During their growth phase, they are covered in a soft, fuzzy skin known as velvet, which is rich in blood vessels and nerves, supplying the rapidly growing bone with nutrients. Moose antlers can grow rapidly, with large bulls adding a pound of bone per day, and growing an inch or more daily. By late summer or early fall, the antlers have reached their full size, and the velvet dries up, becoming itchy. Moose then rub their antlers against trees and vegetation to remove this dead velvet, revealing the hardened antlers underneath.
Why Antlers Are Shed
The shedding of moose antlers is a physiological process controlled by fluctuating hormone levels, particularly testosterone. After the breeding season, or rut, typically in late winter or early spring, bull moose testosterone levels decline significantly. This drop triggers the formation of an abscission layer at the antler’s base where it connects to the skull.
This abscission layer gradually weakens the bone-to-bone connection, leading to the antler detaching from the pedicle. The shedding process is not painful for the moose. Once the antlers are shed, the empty pedicles heal, and the cycle of regrowth begins in preparation for the next breeding season. Shedding antlers offers advantages, such as conserving energy when the heavy antlers are no longer needed for display or combat.
What Happens to Shed Antlers?
Once shed, moose antlers become a valuable resource within the ecosystem, serving as a significant source of essential minerals for various animals. Rodents, such as mice, squirrels, and porcupines, gnaw on shed antlers to obtain calcium, phosphorus, magnesium, and iron.
This gnawing also helps rodents wear down their continuously growing teeth. Larger animals, including coyotes, wolves, bears, and other deer, may also consume parts of shed antlers. Over time, any remaining antler material will decompose, returning its nutrients to the soil and completing a natural recycling process. It is rare to find an intact shed antler in the wild due to this rapid consumption by wildlife.