- Nilgai
-
"Blue Bull" redirects here. For the South African rugby union team, see Blue Bulls.
Nilgai Nilgai male showing bluish tinge Conservation status Scientific classification Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Artiodactyla Family: Bovidae Subfamily: Bovinae Genus: Boselaphus
Blainville, 1816Species: B. tragocamelus Binomial name Boselaphus tragocamelus
(Pallas, 1766)The nilgai (Boselaphus tragocamelus), sometimes called nilgau, is an antelope, and is one of the most commonly seen wild animals of central and northern India and eastern Pakistan; it is also present in parts of southern Nepal. The mature males appear ox-like and are also known as blue bulls. The nilgai is the biggest Asian antelope.
Contents
Description
Nilgai stand 1.2-1.5 meters (4–5 feet) at the shoulder and are 1.8-2 meters (5'9"-6'6") long. Their tails are 40-45 centimeters. Mature nilgai typically weigh 120-240 kilograms (264-529 pounds).
Calves usually weigh 13.6-15.9 kilograms (30-35 pounds) at birth after an 8 month gestation period. 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 that 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. They have a small triangular tail which moves with a very high frequency when they are excited.
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, although old bulls are sometimes solitary.
Distribution
Nilgai antelopes 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 from all along the entire eastern length of Pakistan and over across the border of Rajasthan in the West to the states of Assam and West Bengal in the East; in Nepal, they occur patchily in the southern lowlands. The population density in central India is 0.07 animals per square kilometer.
Historic notes mention the nilgai in southern parts of India but there have also been suggestion that they may be a feral population.
I believe that the Coimbatore and Salem collectorates are almost the only places in Southern India, in which nil-gai are to be found. It is difficult to account for the animals being thus so widely divided from their usual haunts unless as has been generally supposed, these Southern specimens are the progeny of a semi-domesticated herd, which, at some by-gone period, had escaped from the preserve of a native potentate.—A. C. McMaster (1871)[2]Refer to Anderson on shikar in southern India. Nilgai have existed north of Bangalore and probably still do.
Nilgai were introduced in the US state of Texas in the 1920s by the King Ranch for recreational purposes. Over the years some escaped and they are now free ranging in various southern portions of the state.
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 nilgai may be encountered in cultivated or semi-urban areas.
Nilgai in India
A blue bull is called a nil gai or nilgai in India, literally from nil meaning blue and gai meaning a bovine animal (literally 'cow'). In fact nilgai were known as the Nilghor (nil = blue , ghor = horse) during the rule of Aurangzeb (Mughal Era) (Gautam Masters dissertation unpubl : Dept. of Wildlife Sciences, Aligarh Muslim Univ). Nevertheless the local belief, that nilgai are a cow and hence sacred, has protected it against hunting.
However, nilgai are a crop menace, causing large-scale damages especially along the gangetic belt, especially in the Rohilkhand division of U.P.. It 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 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. Wild populations also exist in the US states of Alabama and Texas and the Mexican state of Tamaulipas where they have escaped from private exotic ranches. The population around the Texas-Mexico border is estimated to be around 30,000[3] and the King Ranch where Nilgai were first released now has around 10,000 of them.[4]
Like many Indian animals, nilgai are often victim to vehicular accidents, and their 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.
Some Texas "exotic ranches" offer nilgai hunting. In January 2010, a nilgai was killed in south Texas by a hunting party that included former White House adviser Karl Rove.[5]
Footnotes
- ^ Mallon, D.P. (2008). Boselaphus tragocamelus. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 29 March 2009. Database entry includes a brief justification of why this species is of least concern.
- ^ McMaster, A. C. (1871) Notes on Jerdon's Mammals of India. Higginbothams, Madras. (pp. 123-124)
- ^ "Nilgai Antelope in Northern Mexico", Journal of Wildlife Diseases, 2011
- ^ King Ranch Nilgai Hunting
- ^ Rove, Karl (2010), "Tweet by Karl Rove January 12, 2010", Twitter, http://twitter.com/KarlRove/status/7676662119, retrieved 2010-01-12
Sources
- 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
Categories:- IUCN Red List least concern species
- Bovines
- Mammals of Asia
- Mammals of Bangladesh
- Mammals of India
- Mammals of Pakistan
- Megafauna of Eurasia
Wikimedia Foundation. 2010.