By Barbara Lundrigan and Trevor Zachariah
Geographic Range
The range of Bos frontalis is Nepal, India to Indochina, and the Malay Peninsula (Nowak 1999).
Habitat
Inhabits forested hills and nearby grassy clearings. Can be found at elevations up to 1800 meters (Nowak 1999).
Terrestrial Biomes:
rainforest 
.
Physical Description
(1430 to 2200 lbs; avg. 1815 lbs)
(8.2 to 10.82 ft)
Typical length of the body and head is 2.5 to 3.3 meters; tail length ranges from 0.7 to 1.05 meters. Shoulder height is 1.65 to 2.2 meters. A pair of horns is present in both sexes; horn length ranges from 0.6 to 1.15 meters. The hair of B. frontalis is dark reddish brown to blackish brown, with white stockings. Adult males are about 25% larger and heavier than females (Nowak 1999). A characteristic hump of raised muscle can be seen over the shoulders; this is the result of elongated spinal processes on the vertebrae (Buchholtz 1989).
Some key physical features:
endothermic ; homoiothermic; bilateral symmetry .
Sexual dimorphism: male larger, ornamentation .
Reproduction
Breeding can take place at any time throughout the year, though females have an interval of 12 to 15 months between births. The estrous cycle is three weeks long, and estrus lasts one to four days. Gestating females leave the herd during parturition. Usually one 23 kg young is born after 270 to 280 days of gestation. Calves are nursed for up to nine months. Females become sexually mature at two to three years of age. Though lifespan has not been studied in the wild, one captive B. frontalis lived to be 26 years of age (Nowak 1999).
Key reproductive features:
gonochoric/gonochoristic/dioecious (sexes separate); sexual .
Behavior
Herds of B. frontalis typically contain eight to eleven individuals, but can reach 40 individuals. Home range size averages 78 square kilometers (Nowak 1999). Herds usually contain one adult bull and several cows and juveniles. Other bulls may form bachelor herds, or if advanced in age, become solitary. A hierarchy is established in all herds, with a dominant bull at the top and size determining the order thereafter.
Ritualized aggressive behavior is used by both sexes to maintain the dominance hierarchy. Aggressive behavior is characterized by broadside charges and movement of the head horizontally and vertically. The degree of vigor and height of the head express varying levels of aggression.
Vocalizations include an alarm call, which consists of a high-pitched snort and a growling "moo." Bulls have two additional calls. The first is the herd call, which halts the herd and brings it together. The second is a roaring that can last for hours during mating periods. Licking is also used in communication. Females lick their calves to form stronger relationships with them. Lower-ranking individuals lick higher-ranking individuals. Also, mating pairs lick each other during breeding.
The daily behavior of B. frontalis begins with the herd exiting the forests into grassy areas to feed in the morning. The afternoon is spent resting and ruminating. More feeding ensues in the evening, and at night the herd reenters the forest for resting and sleeping.
Shyness causes aversion to humans, and in largely disturbed areas, B. frontalis can become entirely nocturnal (Buchholtz 1989). There have been reported cases, though, of B. frontalis attacking and killing human pursuers that get too close (Nowak 1999). Predators of B. frontalis include tigers and humans (Buchholtz 1989).
Key behaviors:
motile ; social ; dominance hierarchies .
Food Habits
Classified as an herbivore, B. frontalis is both a browser and a grazer. It prefers green grass, but otherwise will consume coarse, dry grasses, forbs, and leaves (Nowak 1999).
Economic Importance for Humans: Positive
Humans use B. frontalis as a species for sport hunting (Buchholtz 1989).
Ways that people benefit from these animals:
food .
Conservation Status
IUCN Red List: [link]:
Vulnerable.
US Federal List: [link]:
Endangered.
CITES: [link]:
Appendix I; No special status.
The population of B. frontalis is in decline due to hunting and habitat alteration and destruction. It has been estimated that there are only 1000 individuals left in the wild (Nowak 1999). This species is also very susceptible to domestic cattle diseases, such as hoof and mouth disease and rinderpest. Diseases are spread by domestic cattle that are driven into the habitat of B. frontalis to graze (Buchholtz 1989).
Contributors
Barbara Lundrigan (author), Michigan State University. Trevor Zachariah (author), Michigan State University.
