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Bos bison Linnaeus 1758

Order Artiodactyla : Family Bovidae

DESCRIPTION. A large, cow-like mammal with distinct hump in the shoulder region; head, neck, shoulders, and forelegs with long, shaggy hair; hind part of body with short hair; head heavy with short, curved, black horns; tail short and ending in tuft of hair; color brownish black anteriorly, brownish posteriorly. Dental formula: I 0/3, C 0/1, Pm 3/3, M 3/3 × 2 = 32. External measurements of males approach: total length, 3,400 mm; tail, 610 mm; hind foot, 610 mm; height at shoulders, 1,800 mm; females somewhat smaller. Weight of bulls, 700–1,000 kg; females, 300–400 kg.

Bos bison

DISTRIBUTION. Before extirpation from the state, American bison were widespread in the western two-thirds of Texas. Bison are now present in Texas only in private herds on some ranches, and a captive herd was recently established at Caprock Canyons State Park in the Panhandle.

Distribution of Bos bison

SUBSPECIES. Bos b. bison.

HABITS. In early days the American bison (buffalo) was found in great numbers over a vast range in North America. With the westward expansion of the white settlers, it became an object of exploitation on a tremendous scale, which resulted in its total disappearance from the East and its almost complete extermination over much of its western range. By 1825 it had become practically extinct east of the Mississippi River. The building of the transcontinental railways after 1830 hastened the slaughter of the vast herds west of the river. In the 1870s, hundreds of thousands were recklessly killed for their hides and tongues. In 1877–1878 the last great slaughter of the southern herd took place south of the main transcontinental railroads. In the north their numbers likewise rapidly decreased.

When protection of the buffalo was under consideration by the Texas Legislature, General Phil Sheridan opposed the bill, pointing out that the sooner the buffalo was eliminated the sooner the Native Americans would be starved into submission. Consequently, before 1880 both the buffalo and the Native Americans of the plains had all but disappeared.

During the big slaughter of 1877–1878, there were reported to be 1,500 hunting outfits working out of Fort Griffin (Shackelford County) alone. More than 100,000 hides were taken in the months of December and January of that winter. From 1881 to about 1891 there were shipments of buffalo bones from Texas totaling $3 million in value.

In the late 1880s it was realized that the American bison was approaching extinction. By then only a few privately owned herds and a herd in Yellowstone National Park remained. It was not until May 1894 that an effective law for the preservation of the bison was passed by the US Congress, and, subsequently, the various herds were built up in the United States and Canada. By 1933, the total population of bison in North America was estimated at 21,000, of which the greater part (17,000) was in Canada on the Buffalo National Park near Wainwright, Alberta.

The bison of the western United States is normally a dweller of open prairies. The subspecies B. b. athabascae of Canada and the Old World relative (Bos bonasus), however, are forest animals. Our plains bison also lacks the keen eyesight of most plains dwellers but has a keen sense of smell, suggesting that at some remote time in the past the plains bison, too, lived in woodland areas.

Bison are gregarious creatures that live together in herds; however, the old bulls lead a more or less solitary existence, especially in spring and early summer. During the period of rut in July and August, and again in winter, the old bulls tend to be more tolerant of the herd. Normally, bison are unobtrusive, but when angered or when called on to protect their calves they are vicious and dangerous. As with domestic cattle, old bulls are surly and may attack with slight provocation, as will cows with calves.

The daily activity of bison is much like that of domestic cattle. The primary feeding periods are early morning and late afternoon, with midday given over to cud chewing, siesta, and wallowing. Normally, nighttime is a period of rest. Formerly, the plains bison migrated seasonally, going south as far as Florida and Texas in winter and northward again in summer. Their normal gait is a plodding walk, which may break into a swinging trot or, when frightened or angered, a stiff-legged gallop. Plains bison are predominantly grazers, feeding mostly on grasses and secondarily on forbs. Browse species contribute slightly to their diet. Because of their similar diets, competition between bison and domestic cattle for range forage is so great we cannot afford, for economic reasons, the return of the bison to anything like its former numbers—unless bison can replace a portion of the requirement for beef.

During the rut, both young and mature bulls are promiscuous in mating behavior, but usually only the large, mature bulls participate in the actual breeding process. Young and undersized bulls are driven from the herd to linger on the outskirts and await the opportunity to participate whenever the herd bull is off guard. As with domestic cattle, a scale of social dominance is established, with each bull dominating those below him on the scale.

The period of gestation is 8.5–9 months, and the calves arrive in April, May, or early June. One calf at a time is the rule; twins are rare. The young normally are weaned in late fall, but occasionally young continue to nurse until the arrival of the next calf. Sometimes cows breed only in alternate years. Sexual maturity is reached in the third year. According to Victor H. Cahalane of the National Park Service, cows have remained productive for 40 years, indicating a life span of at least 45 years.

POPULATION STATUS. Rare. American bison, once numbering in the millions and ranging over most of the state, were hunted to near extinction in the wild in Texas. The last verified report of wild bison was from the northwestern part of the Panhandle in Dallam County in 1889; only a few individuals (part of the captive Goodnight herd) remained.

CONSERVATION STATUS. The IUCN lists the American bison's status as near threatened, and it does not appear on the federal or state lists of concerned species.

REMARKS. In 1996, a visionary plan was set in motion to rebuild a herd of southern plains bison and reestablish them in the wild. This plan was made possible over 100 years ago by the foresight of legendary rancher Charles Goodnight, owner of the JA Ranch in the Palo Duro Canyon area. Goodnight witnessed firsthand the great slaughter of the plains bison in Texas during the 1870s. Fearing that the end was near for the southern plains buffalo, Goodnight captured a small herd of the animals and relocated them to his ranch. There, for more than a century, the animals and their offspring ranged freely over the JA Ranch and surrounding ranches of West Texas. These animals were the last genetically pure examples of the original stock of the southern plains bison and are unique from all other bison in the world today.

In 1994, TPWD became concerned about the future of the Goodnight herd, as its size had declined to fewer than 30 individuals. In 1996 it was determined by genetic testing that the animals were indeed unique, and efforts were initiated to preserve the herd. Later that year, the owners of the JA Ranch donated the bison to TPWD. The animals were transferred to breeding facilities at Caprock Canyons State Park in the winter of 1997–1998, and the Texas State Bison Herd was established. The short-term goal of TPWD is to preserve these invaluable animals and allow the population to grow. The long-range goal is to restore the southern plains bison on a 100,000-acre refuge within its historic Panhandle range as part of a native prairie ecosystem. Hopefully, in the near future these magnificent and unique creatures will once again roam the open plains of Texas.

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From The Mammals of Texas, Seventh Edition by David J. Schmidly and Robert D. Bradley, copyright © 1994, 2004, 2016.  Courtesy of the University of Texas Press.

Natural Science Research Laboratory