Indira Gandhi Wildlife Sanctuary and National Park (IGWLS&NP) is a protected area named after Prime Minister Indira Gandhi who visited the park on October 7, 1961. It is often called "Topslip", a village in the northeast corner of the park which is the main visitor center. This name is derived from the local 19th century practice of sliding Teak timber logs down from the hills. It is located in the Anaimalai Hills of Pollachi, Valparai and Udumalpet taluks of Coimbatore District, Tamilnadu state, South India. The 108 km² National Park is the core area of the 958 km² Indira Gandhi Wildlife Sanctuary, formerly called Anaimalai Wildlife Sanctuary. It was notified as a sanctuary in 1974 and 108 sq.kms of its unique habitats at 3 places - Karian Shola, Grass hills, Manjampatti were notified as National Parks in 1989.
The Park and the Sanctuary is under consideration by UNESCO as part of The Western Ghats World Heritage site. The Sanctuary and the Palni Hills in Dindigul District form the Anaimalai Conservation Area.
Threatened species of mammals in the sanctuary include:
the endangered Bengal tiger, Indian elephant, Dhole (Asiatic wild dog), Nilgiri tahr and Lion-tailed macaque.
the vulnerable Brown Mongoose, Gaur, Malabar Spiny Dormouse, Nilgiri langur, Rusty-spotted cat, Sambar Deer, Sloth bear and Smooth-coated Otter,
the near threatened Indian Giant Squirrel, Indian Leopard and Indian Pangolin.
IGWS is a Project Elephant sanctuary and was declared a Project Tiger sanctuary in 2008.
The Steering Committee of Project Tiger granted approval in principle to inclusion of Indira Gandhi WLS and NP and nine additional protected areas under Project Tiger in 2005.
Animals of least concern here include: Golden jackal, Leopard cat, Jungle cat, Spotted deer, Barking Deer, Mouse Deer, Wild Boar, Common langur, Bonnet macaque, Asian Palm Civet, Small Indian Civet, Indian Gray Mongoose, Striped-necked Mongoose, Ruddy Mongoose, Grey Slender Loris, Indian Giant Squirrel, Indian Crested Porcupine, Indian Pangolin, and Three-striped Palm Squirrel.
Over 250 species of birds have been identified in the Park . Some of the most important groups include, cormorants, ducks, teal, darter, partridge, quail, jungle fowl, spurfowl, Indian peafowl, parakeets, hornbills, barbets, drongos, orioles, shrikes, warblers, flycatchers, woodpeckers, chloropsis, trogons, kingfishers, storks, egrets, fish eagle, hawk eagles, harriers, falcons, kites, owls and nightjars.
It is home to 15 of 16 species of birds endemic to the Western Ghats.
Reptiles include Toads, Spotted Leaping Frog and Leith's Leaping Frog, Black Torrent Frogs, tree frogs, Pythons, Cobras, Kraits, Vipers, Grass Snakes, Forest Cane Turtles, Travancore Tortoises, Flapshell Turtless, Star Tortoises, Flying lizards, Chameleons and Forest Lizards.
315 species of butterflies belonging to five families have been identified in the Annaimalai Hills. 44 are endemic to the Western Ghats.
The park is home to a wide variety of flora and fauna typical of the South Western Ghats. There are over 2000 species plants of which about 400 species are of prime medicinal value. The diverse topography and rainfall gradient allow a wide variety of vegetation comprising a mix of natural and man-made habitats. The former includes wet evergreen forest and semi-evergreen forest, montane shola-grassland, moist deciduous, dry deciduous, thorn forests and marshes. Tropical wet evergreen forest is found at an altitude of 600m to 1,600m. Tropical montane forests occur at higher elevations and are interspersed with montane grasslands, forming the shola-grassland complex. Much of the original evergreen forest now contains introduced teak plantations. Bamboo stands and reeds occur in the natural forests. Tree cover is provided by Hopea parviflora, Mesua ferrea, Calophyllum tomentosum, Vateria indica, Cullenia excelsa and Mangifera indica, Machilus macrantha, Alstonia scholaris, Evodia meliaefolia, Ailanthus and Malabaricum and Eucalyptus grandis. The area is home to Podocarpus wallichianus, a rare South Indian species of conifer.
The IGWLS is managed by the Wildlife Warden (Wildlife Warden Office, 178 Meenkarai Road, Pollachi, Ph: 04259-225356) and falls within the administrative control of the Coimbatore Forest Circle headed by the Conservator of Forests, Coimbatore.
Travel by road from Coimbatore to Pollachi (40 km) to the Wildlife Warden's Office for visitor permit and then by road to Top Slip (35 km), or to Udumalpet (40 km - Amaravathi and Udumalpet range), or to Vaalparai (65 km - Vaalparai and Manamboly range)
The ideal months to visit the Park are May to January. Entry time is between 6 am and 6 pm. The Park has a large tourist complex at Top Slip that houses many cottages, rooms, and dormitories for visitors. Visitors can get around the park by trekking and a safari van.