- Parambikulam Tiger Reserve is a well-protected ecological portion of the Anamalai sub unit of Western Ghats, as it 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, semi evergreen, moist deciduous, dry deciduous and shola forests. Other unique habitats like montane grasslands and marshy grasslands known locally as ‘vayals’ are here. Considerable extent of man-made teak plantations and the deep freshwater ecosystem created by the construction of three dams add to the diversity of the place.
- The floral diversity of the tiger reserve is extraordinary. As per the research report of Kerala Forest Research Institute by Sasidharan (2002), the sanctuary 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. This includes about 70 species of orchids also. The inventory is not completed yet. This magnitude of floral richness is due to the mosaic vegetation pattern in this sanctuary.
- The tiger reserve supports healthy population of several endangered wild animals. The presence of about 20 tigers underscores the healthiness of this ecosystem. Most of the herbivorous species of the Western Ghats viz., Asian elephant, spotted deer, sambar and barking deer (Muntjac) are found here. Parambikulam tiger reserve supports one of the highest densities of gaur population in Southern India. The only South Indian wild goat, the Nilgiri Tahr is found on the high altitude rocky hills and grasslands in the tiger reserve. A healthy population of about 250-300 Lion-tailed macaques among the other primates and arboreal animals are found here. Rodents like Malabar giant squirrel, and flying squirrel are among the important arboreal animals. The 38 significant population of resident and migratory avifauna of about 273 species makes the tiger reserve a bird watchers paradise. Among the aquatic fauna, crocodiles, otters, freshwater fish especially Mahseer, an endemic game fish are worth mentioning. The tiger reserve is also home of several rare small animals like Tarantula (large bodied spiders).
- There are several endemic, rare, endangered and threatened species of flora and fauna adding to the diversity of the reserve. To name a few, Haplothismia exannulata, a monotypic genus of Burmanniaceae rediscovered here after 1951; Coscinium fenestratum and Utleria salicifolia, the IUCN ‘redlisted’ medicinal plants endemic to Anamalais; Tomopterna parambikulamana, an endemic frog of Parambikulam and Garra surendranathanii, an endemic sucker fish can be mentioned among the others like King Cobra, Lion-Tailed Macaque, Nilgiri Tahr, Tiger, etc.
- The Tiger Reserve being a part of major ecological continuum from Peechi to Eravikulam through Anamalai, aids the survival of large viable populations of wildlife. The Parambikulam valley extends from East to West opening up migratory routes for wild animals from Nelliampathy to Eravikulam National Park. Parambikulam tiger reserve along with Indira Gandhi Wildlife Sanctuary forms the northern most extension of Anamalai portion of the Western Ghats before being blocked by Palakkad Gap. Thus migration of animals like elephants and subsequent genetic exchange between their populations is facilitated. Because of such conservation importance, this sanctuary has declared as a Tiger Reserve in 2010.
- The four man-made reservoirs and natural river systems besides adding to the beauty of the place support several unique life forms. Also, Parambikulam provides the life support system for the human population living in the plains of Kerala and Tamil Nadu by supplying good water and air.
- This tiger reserve is the home of about 1,300 people belonging to several tribal and non-tribal communities whose livelihood is almost fully dependent on the forests of the tiger reserve. This tiger reserve can be treated as a model for peaceful co-existence of tribal people and wildlife
- About 1/3rd of the tiger reserve area is occupied by Teak monoculture plantations that are in various stages of extraction. The approximate stumpage value of these plantations is an astounding Rs. 2000 crores (US$ 304 Millions)
- The intangible benefits accrued from the tiger reserve are enormous and invaluable. Especially this is the carbon sink and an important life-support system for the vast adjacent plains of Kerala and Tamil Nadu.
- The aesthetic appeal of the tiger reserve with its lush greenery, magnificent wildlife, inviting peaks, serene valleys, meandering rivers and placid lakes, is beyond compare.