175 National Seminar on Conservation of Eastern Ghats, March 24-26, 2002, held at Tirupati, Andhra Pradesh Impact of Anthropogenic pressure on the biodiversity of Kolli Hills, Eastern Ghats Arun P.R., Rajasekaran A, Azeez P.A and Bhupathy S. Salim Ali Centre for Ornithology & Natural History, Anaikatty, Coimbatore 641 108. Abstract Kolli hills are an isolated hill range of the discontinuous Eastern Ghats mountain system, situated in the Namakkal district of Tamil Nadu. Kolli hills has an area of 282.92 Sq.Km, out of which nearly 50% is under cultivation and remaining area includes reserve forests, plantations, mines and human habitations. Although, forests in Kolli hills come under Reserve Forest Category, anthropogenic pressures from various activities such as lopping, felling, grazing, mining etc, are so acute that hardly little climax vegetation is left undisturbed. During the faunal survey conducted during the present short –term study twenty-three species of butterflies, seven amphibians, thirteen reptiles, sixty-two birds and four mammals were recorded. It is felt that is highly essential to implement earnest conservation measures to relieve the pressures off the remaining wild habitats in Kolli hills in order to manage the cultural landscape’ of Kolli hills sustainably in future. INTRODUCTION T he Kolli hills stretches around 29 Km north to south and 19 Km east to west covering an area of around 283 Km 2 . Kolli hills on the western, eastern and southern sides rise abruptly from the plains and are mostly forested. The northern side descend to the plains by gentle slopes, and these areas are mostly under agriculture. The mean elevation of the Kolli hills is around 1000 msl. Mean annual rain rainfall is around 1000 mm. Kolli hills consist of heterogeneous vegetation along an elevation gradient. The foothills are covered with scrub forests. Dry deciduous, mixed deciduous and evergreen forests occur with increasing elevations. Around 125 Km 2 area of Kolli hills are under forest cover. The observations presented in this paper were made during the field survey in August 2000. Human induced perturbations have caused multi faceted impacts on the local biodiversity and the livelihoods of the local people. VEGETATION A total of 916 taxa were reported from the Kolli hills, which includes 854 angiosperms, 57 pteridophytes and five gymnosperms (Ranjitakani 1998). Scrub, dry deciduous, evergreen and riverine forests are the major forest types present in the area. Scrub forest Scrub forests are available at the foothills. Moringa concanascens, Commiphora wightii, Canthium dioccum, Limonia alata and Euphorbia antiquorum are dominant trees. Common shrubs are Acalypha fruticosa, Lantana camara, Securinega leucopyrus and Tarenna asiatica. Pterolobium hexapetalum, Cissus quadrangularis, Cardiospermum halicababum, Asparagus racemosus and Jasminum auriculatum are common climbers. The herb layer is dominated by Mollugu oppositifolia, Justicia tranquebariensis, Blepharis maderaspatensis, Ocimum canum, Tephrosia purpurea, Polycarpae corymbosa, Borreria, Desmodium triflorum and Boerhavia diffusa. Dry deciduous forest Dry deciduous forests are seen at higher elevations (above 700m.) Tree species such as Anogeissus latifolia, Pterocarpus marsupium, Dalbergia lanceolaria and Tectona grandis dominate the tree layer. Shrub species such Toddalia asiatica, Lantana camara, Chromolaena odorata, Tarenna asiatica, Acalypha fruticosa and Securinega leucopyrus. Herb layer is dominated by Justicia simplex, Blepharis maderaspatensis, Hemionitis arifolia,