Indian One horned Rhinoceros - Central Zoo Authority

Biology
The one horned rhinoceros inhabits riverine grasslands of the Terai and Brahmaputra
basins. The species prefers alluvial plain grasslands, but is also found in adjacent
swamps and forests. The current populations are restricted to habitats surrounded by
human-dominated landscapes, so that the species often strays into adjacent cultivated
areas, pastures, and secondary forests. The one-horned rhinoceros is a grazer. They
are associated with the water bodies for feeding, wallowing and resting. The diet
includes mainly grasses, but also some fruit, leaves, shrub and tree branches, and
cultivated crops. The species also utilizes mineral licks regularly.
Greater one-horned rhinos have a brownish-grey, hairless skin, which develops thick
folds, resembling armour plating. Several prominent folds protect the neck. The skin has
a maximum thickness of upto four cm; the subcutaneous fat is 2-5 cm thick and well
supplied with blood, which helps thermo-regulation. Between the folds, around the
stomach, the inner legs and the facial area, the skin is rather soft and thin. The tail lies
embedded between the hind-leg folds. They weigh between 1,800 - 2,700 kg, shoulder
height is 1.75 - 2 metres, and are 3- 3.8 metres long. Animals in the wild are in general
lighter in colour than their captive counterparts. Greater one-horned rhinos have one
horn, which is typically 20-61 cm long, and weighs up to three kg.
Females are sexually mature at 5-7 years of age; males at 8-10 years. Mating takes
place throughout the year and there is no specific calving season. Their gestation
period is approximately 16 months (465-490 days), and they give birth every three
years. The interval between births ranges from 34–51 months. The birth weight ranges
from 60-77 kg. A calf drinks on average 20-30 litres of milk per day and grows by 1-2 kg
daily. They start nibbling / feeding on roughage at the age of 3-5 months and continue
to suckle up to the age of 20 months. In the wild, youngsters are predated by tiger.
Adults have no enemies other than humans. Calf stays with its mother for at least four
years. Usually mother rhino keeps her calf away from other rhinos and is very
aggressive. This period is crucial to new born calf as it is vulnerable to predation. The
longevity or life span of a rhino in the wild is 30-35 years and in captivity 47 years. The
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