|Subspecies|| A. a. americana|
A. a. mexicana
A. a. oregona
A. a. peninsularis
A. a. sonoriensis
|Population||1,000,000 (2011 est.)|
|Conservation status||Least concern|
The pronghorn (Antilocapra americana) is a species of hoofed mammal native only to the grassland areas of North America, and is the only surviving member of the family Antilocapridae. Once as numerous on the plains as bison, their numbers were severely-reduced through over-hunting and the placement of cattle fencing; they have since rebounded, but with two subspecies listed as endangered.
Pronghorns are small ruminants, similar in appearance to antelopes yet unrelated, standing 2.5-3.5 feet at the shoulders, and weighing in at 105-120 pounds. Males are slightly larger than females. The coat is a tawny-brown, with white underbelly and rump; males are characterized by having a black blaze on the muzzle and a black chin patch at the nape of the neck. Males bear horns up to 14 inches long, curling backward at the apex, with a small single "prong" jutting forward, hence the name of the animal. Females bear a short spike up to four inches long. The horns are made of keratin - the same material which make up hair, nails, and hoofs - over an internal, bony core. Similar to deer rather than antelopes, the horn sheath is shed in late summer after the breeding season, to regrow again during the following year.
The eyes are extremely large and sensitive; pronghorns are alert animals and have been known to detect movement up to four miles away. The neck is massive in both sexes, containing a windpipe that is "oversize" for such an animal, again differentiating it from true antelopes, and enabling the pronghorn to gulp large amounts of air while on the run. Pronghorns are considered the fastest mammal on earth over a sustained distance, capable of sprinting to 60 miles an hour over a course of a hundred yards, and up to 50 miles an hour over several miles; by comparison, the fastest mammal over a short distance - the cheetah - can do up to 70 miles per hour, but quickly tires out after one hundred yards.
- Antilocapra americana americana; Canada: southern Saskatchewan and Alberta to United States: southwestern Minnesota, south to central Texas, west to southern California coastline
- Antilocapra americana mexicana; northern Mexico, southern United States
- Antilocapra americana oregona; United States (Oregon)
- Antilocapra americana peninsularis; Mexico (Baja California Sur)
- Antilocapra americana sonoriensis; Arizona to northern Mexico (Sonora)
Pronghorns are an open plains mammal, predominantly found in the Great Plains regions of the western United States and southern Canada. Three subspecies are found in the scrub and desert regions of Arizona and Mexico. They prefer low vegetation, no higher than about thirty inches, as they are watchful for predators.
As of 2011 the species as a whole has been estimated to have a population of 1,000,000 animals; as a result the ICUN has listed it as least concern. At one time the population was believed to be at least 35,000,000 about the beginning of the 19th century, making the pronghorn the most numerous plains animal after the bison. Severe over-hunting in addition to habitat loss (agriculture, urban expansion, and mining) reduced numbers to less than 20,000; conservation efforts brought the species back up to current levels.
Two subspecies are listed as endangered: A. a. sonoriensis and A. a. peninsularis. Both subspecies are fragmented within their range and have populations of less than 400 animals each. Illegal hunting, roads, altering of habitat in favor of livestock as well as fencing which hinders migration has been cited as factors, with the USFWS taking steps to plan a recovery. Added are the proposed border wall between the United States and Mexico, as well as watch towers; both of which would be meant to hinder illegal human immigration. Left unsaid by these environmentalists is the human waste and debris left behind by these migrants, which directly and immediately affects pronghorn habitat.