These species exhibits a high degree of sexual dimorphism; the male is larger than the female, is strikingly coloured in black and white, and sports a magnificent pair of spiralling horns. The black of the male is replaced by an inconspicuous brown in the female. The aggressive behaviour is commonly seen throughout the year. The reproductive behaviour of black buck was recorded during the present study. The mating was primarily observed in the months of March and October. The young ones yellowish fawn in colour. After about three years it begins to turn black. A buck has a brown black coat. The colour usually fades a little during summer but after the rains the velvety texture acquires sheen.