A “buck” refers to a male deer, a term used for various species including white-tailed deer, mule deer, and fallow deer. The presence of antlers is often considered a defining characteristic of bucks, raising questions about instances where this common perception might not hold true.
Understanding Antlers in Bucks
Antlers are bony structures that grow from a deer’s skull, specifically from attachment points called pedicles. They are composed primarily of bone, unlike horns which are permanent and made of keratin. Deer typically grow and shed a new set of antlers annually, a rapid process. Antler growth begins in late spring, covered by a vascularized skin layer called velvet that supplies nutrients and oxygen. As summer progresses, the antlers mineralize and harden, and rising testosterone levels cause the velvet to dry and be shed, usually by early autumn.
The primary purpose of antlers for male deer is to establish dominance and compete for breeding rights during the mating season, known as the rut. Bucks use their antlers in sparring matches, locking heads and pushing to assert their strength and social status. Antlers also serve as visual signals of male quality, with larger antlers potentially indicating age, health, and genetic fitness, which can attract female deer. While they can be used for defense against predators, this is not their main function, as deer primarily rely on evasion.
The Exceptions: When Bucks Don’t Have Antlers
Not all male deer possess antlers, and several factors can contribute to this. Young bucks, specifically fawns, are born without antlers, developing small pedicle bumps at about four to five months of age, with their first noticeable antlers appearing as yearlings. These initial antlers can range from simple spikes to more complex formations. Conversely, very old bucks may experience a decline in antler size and quality as they age past their prime.
Poor health and nutrition significantly impact antler development. Antler growth demands substantial energy and minerals, and a lack of essential nutrients like protein, calcium, and phosphorus can result in smaller or abnormal antlers. Injuries can also affect antler growth, particularly those to the pedicle or testicles, which can disrupt hormone production. For example, a buck with low testosterone due to injury might retain velvet or develop unusual, malformed antlers, sometimes referred to as a “cactus buck.” Additionally, not all male deer species grow antlers; the Chinese water deer, for instance, lacks antlers entirely and instead possesses prominent tusks for defense and territorial contests.
Uncommon Occurrences: Antlers on Female Deer
While antlers are characteristic of male deer, female deer rarely grow them. This unusual phenomenon is almost always linked to hormonal imbalances, specifically elevated testosterone levels. These hormonal fluctuations can occur due to reproductive system abnormalities or tumors.
Female deer that grow antlers typically have smaller, less developed, or unusually shaped antlers, often remaining in velvet or only partially hardening. They rarely achieve the large, hardened racks seen on healthy bucks because they usually do not experience the significant surge in testosterone required for full antler development and hardening. Instances of antlered does are considered extremely rare. An exception to this rarity is the caribou (reindeer), where both males and females regularly grow antlers, though female caribou antlers are generally smaller than those of males.