Pakke Tiger Reserve Research Articles

A Rare Feeding Observation on Water Lilies (Nymphaea alba) by the Capped Langur (Trachypithecus pileatus)

The capped langur (Trachypithecus pileatus, Blyth 1843) inhabits a variety of forest types including tropical dry deciduous, subtropical, broad-leaf and dense evergreen hill forest with many streams, bamboo forest up to 2,000 m and teak and sal plantation forest areas [Srivastava, 1999; Majupuria, 1990]. The capped langur is diurnal and almost entirely arboreal, eating young and mature leaves, ripe and unripe fruits, flowers, seeds, bark and gum [Solanki and Kumar, 2002]. Stanford [1991, 1992], in his studies on feeding behaviours in Bangladesh, observed that, in the dry season, capped langurs survive on mature leaves, some seeds and bamboo shoots, occasionally feeding on gum and termite soil trails. We observed the feeding behaviour of this little known langur in Pakhui Wildlife Sanctuary, Arunachal Pradesh. The Sanctuary (26°54′–27°16′ N and 92°36′–93°09′ E) is located in the south-west of Arunachal Pradesh and is 861.95 km in area. The general vegetation type of the entire tract is classified as Assam Valley tropical semi-evergreen forest (2B/C1 of Champion and Seth [1968]). During a 1-year study on feeding and food preference of this langur, a rare feeding behaviour was observed in September 2002. A troop of capped langurs (consisting of 1 adult male, 4 females and two 9-month-old infants) was observed feeding on the stalks, leaves and flowers of the water lily Nymphaea alba. The monkeys spent most time feeding on the stalks, followed by the leaves of the lilies. Another interesting observation was that the 2 lactating females (who had infants) entered the water to feed on the water lilies so that their bodies were immersed in

Food preference of Rhesus Macaque Macaca mulatta during the pre-monsoon and monsoon season, Pakhui Wildlife Sanctuary, Arunachal Pradesh

Food preference of Rhesus Macaques (Macaca mulatta) in the wild was studied in semi-deciduou s and tropical semi-evergreen forest of Pakhui Wildlife Sanctuary in East Kameng District of Arunachal Pradesh, India during the pre-monsoon and monsoon seasons. A group of 25 Rhesus Macaques of different age and sex classes was observed. Data was collected using group scan method. Rhesus Macaques ate 25 plant species, with a preference for 10 species and the order of preference varied in different months. Highly preferred plant species were Udal (Sterculia villosa), Pipal (Ficus religiosa), Jutali (Altingia excelsa), Panijamun (Syzygium syzygioides) and climbers. The monkeys primarily fed on young leaves, mature leaves, fruits, flowers, flower buds, petioles and seeds during study.

Hornbill abundance in unlogged forest, selectively logged forest and a forest plantation in Arunachal Pradesh, India

The responses of hornbills to selective logging were determined by comparing their diversity and abundance in five habitats classified according to logging history. Relative abundance of three hornbill species was compared along trails in recently logged forest, 20–25-year-old logged forest, unlogged primary forest, a relatively disturbed primary forest and a plantation in Pakhui Wildlife Sanctuary and adjoining reserve forests in western Arunachal Pradesh. The species recorded were the Oriental pied hornbill Anthracoceros albirostris, wreathed hornbill Aceros undulatus and great hornbill Buceros bicornis. The great hornbill was the most common species overall and its abundance varied across habitats, being highest in unlogged forest. The Oriental pied hornbill, which was recorded in only two habitats, seemed to show a distinct habitat preference for secondary growth, rivermargin forests. Wreathed hornbill abundance did not differ between habitats. Differences in species abundance probably reflect aspects of their ecology, such as degree of territoriality, diet and movement patterns, and differential vulnerability to hunting and disturbance. Great hornbill abundance was correlated with large tree density (GBH ≥ 150 cm) and basal area characteristic of unlogged primary forests, while Oriental pied hornbill abundance was negatively correlated with tall forest, indicating its greater numbers in low-stature river-margin forest. Wreathed hornbill abundance was not correlated with any vegetation variable, which is probably related to its reported nomadic movements in search of fruit patches. Hornbill abundance was not correlated with densities of potential food and nest tree species. Although hornbill abundance was not correlated with fig tree density, this was probably because areas where relative fig tree densities were lower often contained a few large fruiting figs. Because hornbills are large mobile birds, they can find resources such as fruiting figs even in otherwise unsuitable habitat.

Hornbill abundance in unlogged forest, selectively logged forest and a forest plantation in Arunachal Pradesh, India

The responses of hornbills to selective logging were determined by comparing their diversity and abundance in five habitats classified according to logging history. Relative abundance of three hornbill species was compared along trails in recently logged forest, 20–25-year-old logged forest, unlogged primary forest, a relatively disturbed primary forest and a plantation in Pakhui Wildlife Sanctuary and adjoining reserve forests in western Arunachal Pradesh. The species recorded were the Oriental pied hornbill Anthracoceros albirostris, wreathed hornbill Aceros undulatus and great hornbill Buceros bicornis. The great hornbill was the most common species overall and its abundance varied across habitats, being highest in unlogged forest. The Oriental pied hornbill, which was recorded in only two habitats, seemed to show a distinct habitat preference for secondary growth, rivermargin forests. Wreathed hornbill abundance did not differ between habitats. Differences in species abundance probably reflect aspects of their ecology, such as degree of territoriality, diet and movement patterns, and differential vulnerability to hunting and disturbance. Great hornbill abundance was correlated with large tree density (GBH ≥ 150 cm) and basal area characteristic of unlogged primary forests, while Oriental pied hornbill abundance was negatively correlated with tall forest, indicating its greater numbers in low-stature river-margin forest. Wreathed hornbill abundance was not correlated with any vegetation variable, which is probably related to its reported nomadic movements in search of fruit patches. Hornbill abundance was not correlated with densities of potential food and nest tree species. Although hornbill abundance was not correlated with fig tree density, this was probably because areas where relative fig tree densities were lower often contained a few large fruiting figs. Because hornbills are large mobile birds, they can find resources such as fruiting figs even in otherwise unsuitable habitat.