If you trek deep into the Athirappilly-Vazhachal forests in the Southern Western Ghats, chances are that you may hear, from up in the canopy of trees, a heavy whooshing sound – somewhat similar to that of a jet airplane. If you are lucky, you will catch a glimpse of a magnificent bird, the Great Hornbill. But if the 163-MW Athirappilly hydroelectric project proposed by the Kerala State Electricity Board comes through, these unique birds might vanish from these forests.
The survival of the hornbills hangs in the balance as the Western Ghats Ecology Expert Committee, led by environmentalist Madhav Gadgil, is set to submit its report on the environmental impact of the Athirappilly project by the end of March. If the committee approves the project, it will lead to the submergence of the hornbills' habitat.
The unique low-elevation (180 m MSL) riparian forest in the Athirappilly-Vazhachal area is the only location where you can find all the four South Indian species of hornbills — the Great Hornbill (the State Bird of Kerala), Malabar Pied Hornbill, Malabar Grey Hornbill, and the Indian Grey Hornbill. Their resonating ‘tock.tock.tock' calls and the whooshing sound of their wing flaps have earned them the local name ‘Malamuzhakki' (the one that creates an echo in the hillsides).
“The Athirappilly-Vazhachal forests are the only available nesting location for the threatened Malabar Pied Hornbills (Anthracoceros coronatus) in Kerala. They are endemic to low elevation forests in limited locations of South India and Sri Lanka,” says K.H. Amitha Bachan, a researcher and consultant to Kerala Forest Department and the World Wildlife Fund-India Ecological Monitoring Programme. The other location where this species is found is the Dandeli area in Karnataka.
The prime threat to the species, apart from increased poaching, is lack of suitable nesting trees and feed. Mr. Bachan says that hornbills have an umbilical relationship with the rain forests. Forests undisturbed by humans are crucial for their survival. The natural hollows of high-canopy trees serve as their nests. They are extremely sensitive to disturbances. Though their long bills prevent binocular vision, their sharp eyes and good hearing alert them to the slightest movement on the forest floor. “During our surveys, we located as many as 57 nests in the Vazhachal Forest Division. We found three Great Hornbill nests in a two-kilometre stretch at a 200-metre altitude. This could be one of the last remaining low altitude riparian evergreen forests in the Western Ghats.”