A Study of the Population Structure of Two Species of Non-human Primates in the Similipal Tiger Reserve, Mayurbhanj, Orissa, India

Generally three species of non-human primates occur in the State of Orissa (India). Among these only two species of non-human primates occur in the forests of Similipal hills of Mayurbhanj District. A census for different species of wild mammals occurring in the Similipal Tiger Reserve was undertaken during May, 2004. The results of population structure of two species of non-human primates, viz. Semnopithecus entellus entellus and Macaca mulatta were furnished. The census was carried out for four consecutive days in the line transect method covering a total distance of 122 km. Of the 144 troops sighted consisting of 1,505 Hanuman langurs, the mean troop size worked out to 9.6 ± 1.19. The highest and lowest density of Hanuman langur was 162.5 and 1.7 per km² respectively. Similarly, out of 12 macaque troops sighted consisting of 138 individuals, the troops were made up of 4 to 25 individuals, with a mean of 11.5 ± 1.82. The population density was 10-98.3 per km², with a mean of 26.86.