The Nilgai was introduced in Texas in the 1920s as a zoo animal and is now found free ranging on some ranches there.

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 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. The population density in central India is 0.07 animals per square kilometer.

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).

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.