Gourt Home::Gourt :: Nilgai
- Blue bull redirects here. For the South African rugby union team, see Blue Bulls.
Description
Nilgai stand 1.2-1.5 meters (4-5 feet) at the shoulder and are 1.8-2 meters (6-6.6 feet) long. Their tails are 40-45 centimeters. Mature nilgai typically weigh 120-240 kilograms. The largest males in Texas can weigh over 272 kilograms (600 pounds).
Babies usually weigh 13.6-15.9 kilograms (30-35 pounds) at birth after an 8 month gestation period. Over over 60% of births result in twins, though births of 1 or 3 do occur. They reach sexual maturity at around 18 months and can live as long as 21 years.
Nilgai have thin legs and a robust body, which slopes down from the shoulder. Their long, narrow heads are topped by two small conical horns which are straight and tilted slightly forward.. Horns on trophy males are normally 21.6-25.4 centimeters (8.5-10 inches). They have an erectile mane on the back of the neck and a tubular shaped "hair pennant" on the midsection of the throat.
Female nilgai have a short yellow-brown coat. Males' coats gradually darken to a grey-blue as they reach maturity. They have white spots on the cheeks and white coloring on the edges of the lips. They also have a white throat bib and a narrow white stripe along the underside of the body that widens at the rear.
Nilgai can be found in single sex or mixed sex herds of 4-20, though old bulls are sometimes solitary.
Distribution
They are found in the north Indian plains from the base of the Himalayas in the north, down to the state of Karnataka in the South, and from the Gir forest and Rajasthan in the West to the states of Assam and West Bengal in the East. The population density in central India is 0.07 animals per square kilometer.
The Nilgai was introduced in Texas in the 1920's as a zoo animal and is now found free ranging on some ranches there.
Habitat
Nilgai are diurnal and live in grasslands and woodlands where they eat grasses, leaves, buds, and fruit.
In the wild, females and young males gather in herds of about fifteen individuals while older males are often solitary. Individual male or female nilgais may be encountered in cultivated or semi-urban areas.
Nilgai in India
A blue bull is called as Nil gai or Nilgai in India, literally from nil meaning blue and gai meaning a bovine animal (contrary to popular belief, a female bovine such as a cow is called gabhih in formal sanskrit). This local belief, that the Nilgai is a cow and hence sacred, has protected it against hunting.
However, the Nilgai is a crop menace and has been declared as vermin in northern India and they may be legally hunted after obtaining a permit.
Habits
Blue bulls mostly live in herds and in winter, male blue bulls form herds of 30 to 100 animals in northern India. They avoid dense forest and prefer the plains and low hills with shrubs. Blue bulls are usually found in their favoured areas of scrub jungle (acacia forests) grazing upon succulent kader grass. They are not averse to crossing marshlands.
Nilgai can be seen with black bucks (Antilope cervicapra) in the open plains, and in the lower Terai regions they may be seen together with Chital (Axis axis) and 'para' or Hog deer (Axis porcinus). The Chital and Hog Deer, being comparatively smaller in size, usually keep a respectful distance from the much larger Nilgai. Sambar (Cervus unicolor) frequent hills and dense forests and are rarely found in the same habitat as Nilgai.
The main predators of the blue bulls are tigers (Panthera tigris) and lions (Panthera leo). Leopards are not capable of killing a full grown Nilgai but can take females and calves.
A blue bull can survive for days without water, but they live close to waterholes. The deserts earlier limited their range, but the extension of irrigation canals and proliferation of tube-wells in the Thar desert have helped them colonise the desert districts of Jodhpur, Barmer, Jaisalmer, Bikaner and Ganganagar.
Blue bulls generally come to the same place to deposit their droppings.
Status
The estimated population of Nilgai in India is approximately 100,000. The Texas population is estimated to be around 15,000 individuals.
Like many Indian animals, Nilgai are often victim to vehicular accidents and nilgai carcasses are often seen on major highways in northern India. The main threat to this species is the loss of habitat due to human population growth.
The species is declared by the IUCN as being at low risk of extinction.
Wild populations also exist in Alabama and Texas where they have escaped from private exotic ranches.
References
- Database entry includes a brief justification of why this species is of least concern
- Menon, Vivek. A Field Guide to Indian Mammals. Dorling Kindersley, Delhi, 2003.
- Sheffield, William J., et al. The Nilgai Antelope in Texas (College Station: Texas Agricultural Experiment Station, Texas A&M University System, 1983).
External links
Nilgauantilope | Antilope Nilgaut | Mėlynoji antilopė | Nijlgau | Nilgau
"Nilgai"