Parambikulam is one of the premier Tiger Reserves of India and is endowed by nature in terms of species, habitat and ecosystem diversity, characterized by functional human-ecological affinities. It stood 7th in the country in terms of Management Effectiveness in the 2018 Assessment (among 50 Tiger Reserves in the country).
The area was declared a Tiger Reserve during 2010 at a total extent of 643.66 sq km, out of which an extent of 390.89 km2 has been declared as the core or critical tiger habitat and 252.77 km2 as the buffer zone of the Tiger Reserve.
Parambikulam is a well-protected part of the Nelliampathy – Anamalai sub unit of the Western Ghats and is buffered by ecologically similar forests of other Forest Divisions and Protected Areas of Kerala and Tamil Nadu.
The Reserve supports diverse habitat types viz., evergreen forests, moist and dry deciduous forests and grasslands. Other unique habitats like montane grasslands and marshy grasslands (locally known as ‘vayals’) are extensively found.
Considerable extent of man-made teak plantations and the deep freshwater ecosystem (Reservoirs) created by the construction of three dams during the 60s add to the diversity. The Reserve supports healthy population of several endangered fauna and the presence of tigers and other co-predators in the landscape emphasizes the ecological importance of this region. Most of the herbivore species of the Western Ghats such as the Asian elephant, Gaur, Spotted deer, Sambar and Barking deer (Muntjac) are found here.
Parambikulam has one of the highest densities of Gaur population in Southern India. The only South Indian wild goat, the Nilgiri Tahr is also found on the high-altitude rocky hills and grasslands in the Tiger Reserve.
Healthy populations of about 250 to 300 Lion-tailed macaques among other primates are found here. Rodents like Malabar giant squirrel and Flying squirrel are among the important arboreal animals. Significant population of resident and migratory avifauna of about 273 species makes the Reserve a bird watcher’s paradise. Among the aquatic fauna, crocodiles, otters, freshwater fish, especially Mahseer (an endemic game fish) are worth mentioning. The Reserve is also home to several rare small animals like Tarantula (large bodied spiders).
The floral diversity of the Reserve is extraordinary for lack of a better word. As per a recent report of Kerala Forest Research Institute, the Tiger Reserve supports an estimated 1400 species of Angiosperms. So far 1,320 species of flowering plants belonging to 680 genera and 133 families have been identified including about 70 species of orchids. The inventory continues to expand every year. This magnitude of floral richness is due to the mosaic pattern of vegetation in the Reserve. Kariyanshola, which is a part of Sungam Range of the Tiger Reserve has been recognized as a UNESCO World Heritage Site for its immeasurable ecological value to the world.