KOCHI: Cranes stroll the shallows searching for crabs among the lake bed cracks. The water has receded to a thin strip exposing the lake bed. Thattekad bird sanctuary, the tropical rain forest, which harbours many endangered and endemic species, is parched and deserted.
Thattekad, the first bird sanctuary in the state where exotic birds of multiple hues from Siberia and Western countries descend in droves, is losing its sheen. The wetland formed by the waters of Bhoothathankettu Dam, the rain forest and the western hills - a perfect habitat for the avian visitors - is in bad shape. There has been a steep decline in the arrival of migratory birds at Thattekad this year. Environmentalists attribute the dwindling number of birds to climate change leading to destruction of habitat.
According to Ornithologist R Sugathan, the rise in atmospheric temperature has resulted in climatic changes leading to a host of environmental, health and economic hazards.
“The southern states have been experiencing drought conditions for the past few years as the extreme climate of the north is slowly spreading to the south. Water bodies are drying up and the groundwater level is depleting at an alarming rate. Evergreen forests are turning moist-deciduous, while moist-deciduous turn deciduous. If a forest changes its character then the dependent fauna will be affected,” he said.
Three factors influence the arrival of migratory birds at a particular nesting place - safety, availability of food, environment congenial for breeding.
Sugathan said five new species of birds have been spotted at Thattekad this season - Ibis, Amur Falcon, Painted stork, black-and-orange flycatcher and Cotton Teal. But there is a steep drop in the number of birds descending on Thattekad.
“Earlier, we had 322 species of birds here. Now, the number has gone up to 327. While the number of tropical and wetland birds is dwindling, number of water birds has increased in Thattekad these days,” he said.
“There are 580 species of birds in Kerala and 322 of them are seen in Thattekad. Nearly 40 species of migratory birds and 19 international migratory birds arrive here every year. But the dwindling water level is posing a threat to the bird habitat. In five years, the sanctuary may cease to exist,” he said.
As the Irrigation Department opens Bhoothathankettu Dam during the summer, water level depletes in the sanctuary leaving the lake parched, also affecting the vegetation and the availability of food for birds. “There are birds that eat prawns. Prawns need thick, green vegetation to grow. When food supply is affected birds will search for new nesting place,” said Sugathan.
Sajin Kumar K S, assistant professor, Department of Geology, University of Kerala, said the phenological shift experienced in Thattekad is similar to the climatic change triggered by global warming, having a cascading effect on the migration pattern of birds.
Thattekad also suffers from the lack of a system to maintain water level. If the Bhoothathankettu Dam is opened, the sanctuary will dry within 48 hours. The Forest Department is constructing 14 earthen check dams at Thattekad to ensure regular water supply. “The check dams are one metre in height and will ensure minimum water level for birds. Water will be brought to the check dams through a canal,” said range officer Sanjayan.