POPULATION AND FORAGING ECOLOGY OF NILGIRI LANGUR (Trachypithecus johnii) IN RANNI DIVISION OF PATHANAMTHITTA, KERALA
Loading...
Date
2017
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
COLLEGE OF VETERINARY AND ANIMAL SCIENCES, POOKODE WAYANAD
Abstract
Nilgiri langur (Trachypithicus johnii) (Fischer, 1829), black leaf monkey is an
endangered species (Tikadar, 1983) and it is endemic to the rainforests of the Western
Ghats of India. The present study mainly focused on the population estimation and
foraging ecology of Nilgiri langur in Ranni division of pathanamthitta, Kerala. Field
sampling was carried out June to August. Four sampling sites were selected for the
study based on the presence of langur. Observations were made by line transect
method. Estimated group density of langur in the study area was 0.52/km2 with mean
group size of 6.75±1.93. Estimated individual density of langur was 3.5±1.01/km2
.
A total of four sightings of Nilgiri langur the adult females were reported
highest. Adult male and female sex ratio was 1:2.5. Sex ratio in sub adult was 1:1.6.
The study indicate that the langur spent most of the time for feeding followed
by moving and resting 24.9 per cent and 24.5 per cent respectively. Social interactions
such as grooming, vocalization and playing were observed with 6.1 per cent 6.1 per
cent and 3.4 per cent respectively. Lesser proportion of time spent on vigilance.
The per cent time spent on foraging was highest in the morning with peak
foraging was observed during seven and eight hrs. There was smaller peak in the
evening hours. Nilgiri langur observed to forage on 25 plant species in the Ranni
Reserve forest. They foraged mainly on leaves of 84 per cent of plant species.
Description
Keywords
null