The pronghorn (Antilocapra americana) is a unique North American mammal often mistakenly called an antelope due to its speed and appearance. This species is the sole surviving member of its family, found primarily across the grasslands and sagebrush steppe of North America. Its range spans from southern Canada down to northern Mexico. Understanding the social structure and life stages of these animals requires using precise terminology.
Identifying Male Pronghorns
The adult male pronghorn is known as a Buck. Bucks are noticeably larger than females, typically weighing between 100 and 140 pounds, which provides a physical advantage during the mating season. This larger size is the primary indicator of the animal’s sex when observing a mixed herd.
A distinguishing feature of the Buck is the presence of a dark, triangular patch of hair located on the side of its face, just below the ears. These black markings contrast sharply with the white and tan fur of the neck and cheek, making the male easily identifiable from a distance. The patches are a secondary sexual characteristic that serves as a visual signal during the breeding period.
The most obvious difference lies in the headgear; a Buck possesses significantly larger, backward-curving horns with a forward-pointing prong. These horns can reach lengths of over 12 inches and are used extensively in sparring matches to establish dominance before the breeding season. Unlike true antlers, the pronghorn’s horns consist of a bony core covered by a keratinous sheath. The Buck annually sheds this outer sheath after the breeding season, which differentiates it from both deer and true antelopes.
During the late summer and fall, Bucks exhibit territorial behaviors, defending ground where they attempt to gather a harem of females. They mark their territory with scent glands located on their neck and face, signaling dominance to rival males. These displays are directed toward securing mating opportunities during the rut.
Related Pronghorn Terminology
The adult female pronghorn is referred to as a Doe. Does are smaller and lighter than their male counterparts, typically weighing 75 to 106 pounds, and they lack the prominent facial markings of the Buck. While approximately 70% of Does may grow small, straight horns, these are usually inconspicuous, rarely exceeding a few inches, and are much shorter than their body-length ears.
The offspring of the pronghorn are known as Fawns or sometimes Kids. These young are born with a spotted camouflage coat, helping them to remain hidden in the vegetation during their first weeks of life. For the first three to four weeks, the Doe keeps her young separated and hidden, relying on the fawn’s innate instinct to freeze when a predator approaches.
The pronghorn has one of the highest rates of physical development among North American ungulates, enabling Fawns to outrun predators within days of birth. After the initial hiding period, the young may join a small nursery group, which offers protection and allows the Doe to forage more effectively. This distinct terminology helps researchers accurately track the demographics and reproductive success of pronghorn populations.