The Black Rhinoceros or Hook-lipped Rhinoceros (Diceros bicornis), is a species of rhinoceros, native to the eastern and central areas of Africa. Although the Rhino was referred to as black, it is actually more of a grey/brown/white color in appearance.
The adults are solitary in nature, coming together only for mating. Mating does not have a seasonal pattern but births tend to be towards the end of the rainy season in more arid environments.
When in season the females will mark dung piles. Males following females that are in season will follow her; when she defecates he will scrape and spread the dung, making it more difficult for any other adult males to pick up her scent trail.
Breeding pairs stay together for 2–3 days and sometimes even weeks. They mate several times a day over this time and copulation lasts for a half an hour. The gestation period is 15 to 16 months. The single calf weighs about 35–50 kg at birth, and can follow its mother around after just three days. Weaning occurs at around 2 years of age for the offspring. The mother and calf stay together for 2–3 years until the next calf is born; female calves may stay longer, forming small groups. Sexual maturity is reached from 5–7 years old for females, and 7–8 years for males. The life expectancy in natural conditions (without poaching pressure) is from 35–50 years.
Source: en.wikipedia.org/wiki/Black_Rhinoceros - 14.12.2011
As a mainly crepuscular and nocturnal animal the Black Rhinoceros likes to spend the day with sleeping and mud-bathing.