Pronghorn
The pronghorn (Antilocapra americana) stands alone as the only surviving member of the family Antilocapridae. During the Pleistocene epoch, about 11 other antilocaprid species existed in North America, many with long or spectacularly twisted horns. Three other genera known as Capromeryx, Stockoceros and Tetrameryx existed when humans entered North America but are now extinct. The pronghorn's closest living relatives are the giraffe and okapi. These animals belong to the infraorder Pecora, making them distant relatives of deer, bovids, and moschids. Though not an antelope, it is known colloquially in North America as the American antelope because it closely resembles the antelopes of the Old World. This resemblance fills a similar ecological niche due to parallel evolution.
Pronghorns have very large eyes with a 320° field of vision. Their orbits sit high on the skull, allowing them to spot danger from great distances. Each horn consists of a slender, laterally flattened blade of bone that grows from the frontal bones of the skull. A keratinous sheath covers this permanent core and is shed annually. Males possess a horn sheath averaging 15 inches long with a forward-pointing tine. Females have smaller horns ranging from 4 to 6 inches that sometimes barely appear. Adult males weigh between 70 and 180 pounds while females weigh slightly less at 60 to 130 pounds. They have distinct white fur on their rumps, sides, breasts, bellies, and across their throats. The feet feature two hooves with no dewclaws. Pronghorns also possess a gallbladder unlike deer which lack one.
The pronghorn runs up to 55 miles per hour over short distances. It can maintain speeds of 30 miles per hour for several miles. This endurance allows it to outlast predators like cougars and wolves. Carbon and nitrogen isotope comparisons found that American cheetahs once subsisted on pronghorns during the Pleistocene. The animal has a large windpipe, heart, blood volume, erythrocites, and lungs to take in air when running. Its hooves have two long cushioned pointed toes that absorb shock at high speeds. An extremely light bone structure and hollow hair further reduce weight. Male pronghorns tend to have higher physical activity levels than females. They exhibit at least 13 distinct gaits including one reaching nearly 40 miles per hour stride. When alarmed, the white hair on the rump flares open exposing odoriferous glands. This sends a message about present danger through both sight and smell.
Prior to European arrival, the pronghorn was abundant west of the Mississippi River. The prehistoric American Prairie was dubbed the American Serengeti due to millions-strong herds of bison elk and pronghorn. Today the range extends from southern Saskatchewan and Alberta Canada south into Mexico. In Mexico the Sonoran pronghorn may be found from Baja California Sur east through Sonora to San Luis Potosí. They have been extirpated from Iowa Minnesota and Manitoba. Healthy populations stay within 5 miles of water sources. An ongoing study by the Lava Lake Institute for Science and Conservation covers more than 200 miles. Migrating pronghorn start travel from the foothills of the Pioneer Mountains through Craters of the Moon National Monument to the Continental Divide. Dr Scott Bergen notes this confirms Idaho supports a major overland mammal migration. These routes are increasingly rare phenomena in the United States and worldwide.
Plains Indians tribes hunted pronghorn as a principal food source in regions they inhabited. The animal featured prominently in Native American mythology and oral history of the Northwest Plateau. Meriwether Lewis and William Clark made observations on behavior and local hunting practices during their expedition from 1804 to 1806. They described the animal as the Antelope or Goat near the mouth of the Niobrara River in present-day Nebraska. Clark was among the first Euro-Americans to publish killing a pronghorn. The species was not formally recorded until this expedition. George Ord officially described the pronghorn in 1815 as an American ornithologist. Pronghorns were first seen by Spanish explorers in the 16th century but remained unscrutinized until Lewis and Clark arrived.
By the 1920s hunting pressure reduced the population to about 13,000 individuals. Members of the Boone and Crockett Club determined extinction was likely at the turn of the 20th century. George Bird Grinnell stated the club was much concerned about the fate of the pronghorn which appeared to be everywhere rapidly diminishing. In 1927 efforts began to create the Charles Alexander Sheldon Antelope Refuge in northern Nevada. President Herbert Hoover signed executive orders for refuges in 1929 and 1931. Franklin Roosevelt signed another order on the 31st of December 1936 creating a tract that marked true recovery beginnings. Numbers recovered to between 500,000 and 1,000,000 since the 1930s due to habitat protection and hunting restrictions. The Sonoran pronghorn has fewer than 300 in the United States and 200 to 500 in Mexico. Populations are protected under the Endangered Species Act since 1967. Localized declines occur mainly from livestock grazing road construction fences and illegal hunting.
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Common questions
What is the scientific name of the pronghorn?
The scientific name of the pronghorn is Antilocapra americana. It stands alone as the only surviving member of the family Antilocapridae.
How fast can a pronghorn run and how far can it maintain that speed?
A pronghorn runs up to 55 miles per hour over short distances. It maintains speeds of 30 miles per hour for several miles to outlast predators like cougars and wolves.
Where does the pronghorn live today in North America?
The range extends from southern Saskatchewan and Alberta Canada south into Mexico. Healthy populations stay within 5 miles of water sources while some migrate through Craters of the Moon National Monument to the Continental Divide.
When did George Ord officially describe the pronghorn species?
George Ord officially described the pronghorn in 1815 as an American ornithologist. The species was not formally recorded until this expedition following observations by Meriwether Lewis and William Clark during their journey from 1804 to 1806.
What happened to the pronghorn population by the 1920s and when did recovery begin?
Hunting pressure reduced the population to about 13,000 individuals by the 1920s. Franklin Roosevelt signed another order on the 31st of December 1936 creating a tract that marked true recovery beginnings.