Ranging and foraging of Himalayan grey langurs (Semnopithecus ajax) in Machiara National Park, Pakistan.

Grey langurs (Semnopithecus spp.) occupy a variety of habitats, ranging from lowland forests and semi-desert to alpine forests. Little is known about their foraging and ranging in alpine forests, which appear to contain less food than lowland forests. We conducted a 1-year study of Himalayan grey langurs (Semnopithecus ajax) in Machiara National Park, Pakistan, where they occur at relatively high altitudes (range 2000-4733 m). We followed three groups of different sizes and compositions and examined the effects of ecological and social factors on ranging and feeding. The home-range sizes of a small bisexual group (SBG), a large bisexual group (LBG), and an all-male group (AMG) were 2.35 ± 0.92 (mean ± SD; average of four seasons), 3.28 ± 0.55, and 3.52 ± 1.00 km(2), respectively, and were largest in winter for all groups. The daily path lengths of the SBG, LBG, and AMG were 1.23 ± 0.28 (mean ± SD; average of four seasons), 1.75 ± 0.34, and 1.84 ± 0.70 km, respectively; that of the LBG was longer in winter, while that of the AMG was shorter in summer. Both the home-range size and daily path length of the AMG were larger than those of the other groups, even after partialling out the effect of group size differences. The mean altitude used by the langurs and the proportion of animals seen feeding did not differ among seasons or group types. As the mean temperature increased, the altitude used by langurs significantly increased for the SBG and LBG, but not for the AMG. On the other hand, as the temperature increased, the home-range sizes significantly decreased for the SBG and AMG, but not for the LBG. Rainfall did not show any correlation with ranging or feeding in any of the groups. Our results suggested that grey langurs in Machiara National Park employ a high-cost, high-return foraging strategy in winter, and that the ranging of the AMG also reflects its reproductive strategy.

Habitat Utilization and Feeding Biology of Himalayan Grey Langur (Semnopithecus entellus ajex) in Machiara National Park, Azad Jammu and Kashmir, Pakistan.

Habitat utilization and feeding biology of Himalayan Grey Langur (Semnopithecus entellus ajex) were studied from April, 2006 to April, 2007 in Machiara National Park, Azad Jammu and Kashmir, Pakistan. The results showed that in the winter season the most preferred habitat of the langurs was the moist temperate coniferous forests interspersed with deciduous trees, while in the summer season they preferred to migrate into the subalpine scrub forests at higher altitudes. Langurs were folivorous in feeding habit, recorded as consuming more than 49 plant species (27 in summer and 22 in winter) in the study area. The mature leaves (36.12%) were preferred over the young leaves (27.27%) while other food components comprised of fruits (17.00%), roots (9.45%), barks (6.69%), flowers (2.19%) and stems (1.28%) of various plant species.