Rhinoceroses are mammals native to Africa and southern Asia. Five species of rhinoceros exist, all of which are very large animals, capable of growing as large as a ton or more, says the Honolulu Zoo. The five rhinoceros species are all herbivores and live exclusively on plants and other vegetable matter.
The white rhino is almost indistinguishable from its larger cousin, the black rhinoceros. Of the two subspecies of the white rhino, the southern white rhino is the most numerous of all rhinoceroses, says the Honolulu Zoo. These animals eat mostly short grasses that grow up to about 5 or 6 inches high. They eat mostly low-energy grasses like Pennisetum, Panicum maximum and Digiteria. In zoo environments they can eat hays made from alfalfa plants.
Black rhinos can grow as tall as 69 inches at the shoulder and weigh more than 3,000 lbs. The black rhino is found in Africa, and has four subspecies. These animals usually feed at night and forage on small acacia trees, euphorbias and other woody species. Unlike the white rhinoceros, black rhinos do not eat many grasses, though they do eat palatable herbs and succulents.
The Indian rhino is primarily found in northern India and parts of Nepal. These animals live mostly in grasslands and wooded spots in hilly areas near the Himalayan mountains. They are very large animals, with some males growing as large as 6,000 lbs. The Indian rhino eats grasses, leaves, fruits, branches and sometimes cultivated crops when the animal's territory borders on cultivated lands. Grasses make up the majority of the animal's diet, sometimes as much as 80 percent depending on the season.
The smallest rhino species, the Sumatran rhinoceros grows to be about 2,000 lbs. A critically endangered species, the animal is found only on Sumatra, Borneo and a single peninsula Malaysia. These rhinos are browsers, eating leaves, twigs, vines, small shrubs and fruits. They are particularly fond of bamboo shoots, figs and mangoes, and can knock down saplings to feed on the root systems.
The Javan rhinoceros can grow as large as 4,400 lbs. and as long as 11 feet. The animal lives off of shoots, twigs and other plants it can browse on forest floors. It also eats young foliage, fallen fruit and branches of up to about 1 inch that can be broken off of saplings.