The fastest land mammal in the Americas, the pronghorn (Antilocapra americana) is the last surviving member of a once vast and diverse family – the Antilocapridae. Able to reach speeds of over 50 miles per hour, this hoofed mammal inhabits the expanse grasslands of North America. Superficially resembling antelopes, the pronghorn is actually more closely related to giraffes and okapis from Africa. However, they do occupy the same ecological niche as Old World antelopes from Africa and Asia.
Pronghorns have a reddish-brown coat, accompanied by patches of white on their underside and white neck bands. One of the most distinctive features of the pronghorn is their bizarrely shaped horns. Both males and females possess these unique horns (although female horns are much smaller) which split into two curved prongs – hence their name.
As herbivores, pronghorns have quite a simplistic diet. They mainly feed on forbs, grasses, shrubs and other vegetation. Like other even-toed ungulates (hoofed mammals) pronghorns are ruminants. This means they bring up partially digested food from their stomach (known as cud) for further chewing. These speedy mammals have a few native predators including cougars, wolves, coyotes and bobcats.
Gregarious animals, pronghorns live in herds. In the summer months, they will normally live in smaller groups but come together in much larger herds during the winter. Pronghorns mate in the autumn. Around 7-8 months later, females will give birth to one or two young, as twins are relatively common. Just a few days after being born, baby pronghorns can outrun a fully grown human.
Pronghorns were hunted almost to extinction in the early 20th century. In the 1920s hunting pressure had reduced their population to a mere 13,000. However, since then, conservation schemes have been implemented and national parks created to allow their population to return to its former glory. Today, it is estimated that 500,000 – 1,000,000 pronghorns roam the plains of North America, although declines have been recorded in a few localised populations. The pronghorn is legally hunted in western states for the purposes of population control and food in a surprisingly sustainable way.
Their main threats now are habitat loss and fragmentation. The construction of roads, fences and other barriers blocks their traditional migratory routes which is having a damaging ecological impact. Whilst the species is not considered endangered, one subspecies (the Sonoran pronghorn) is severely under threat, with a remaining population of only 200. Dedicated conservation work has helped to revive the pronghorn species so I’m hopeful the same strategy will be applied with the Sonoran subspecies.
Hennessy, K., Wiggins, V. (2014) Animal Encyclopedia: The Definitive Visual Guide. 2nd edn. London. Dorling Kindersley.