Every month, Perur- Sundakamuthur Lake has a surprise for bird watchers. Last September, when it was filled to the brim after the monsoons, it was the Eurasian coots.
“In September and October, we counted over 1000 Eurasian coots,” says R. Sivashankar, a member of a team led by G. Parameswaran. They are doing a systematic bird count of Perur Lake since last February. Once a month, every second Saturday, the team assembles at Perur with a checklist, and records birds, both resident and migratory.
“A systematic avian data collection is the first step in any scientific study,” says Parameswaran.
Early this year, the team recorded garganeys, the migratory ducks in large numbers. In February and March alone, the numbers crossed 900.
They chose Perur Lake as it is fairly pristine compared to other water bodies and also because of negligible levels of industrial pollution in that part of the town. Parameswaran who has done Christmas bird watching and neighbourhood bird watching in the U.S. says some of the wetlands in the city are in good shape but not well-studied.
“We have recorded hundreds of bird species. Water level plays a major role. Birds like cormorants dive into the water and fish, so we see cormorants when the water level is high. Birds like Nathai kuthi naarai, a unique feeder prefers shallow water. When the water level is less, there are more shore birds. We are not looking at instant results. Instead, build data that can help in scientific analysis, and serve as an education tool, and also a tool to monitor the wetland.” There is a consolidated data on the number of species, and birds in every species. Says Sivashankar, “We have counted a total of 102 species, both residents and migratory. During October to March, the migratory season, there were garganeys, ducks and common teals. We saw Northern shovellers, and Northern pintails, in hundreds. We also recorded the numbers of Cotton pygmy goose, Indian spot-billed duck and lesser whistling duck .”
Some notable birds which they have spotted are the Peregrine falcon, Woolly-necked stork, and the adult and juvenile Little ringed plover. Parameswaran says the number of bird species fell during April, the month when most of the migratory pattern is over.
“Most birds start moving now. In January, it was 53 species, mostly water birds including ducks, egrets and herons. In February, it was 60, March turned up 68, and in April the numbers came down to 50.”
Another team member Saivivek says a systematic study of birds takes bird watching to the next level. “We want to continue with our study, and explore possibilities such as a booklet on birds, and may be it can pave the way to promote tourism. For all this to happen the lake has to be clean and pollution-free. The tank bund that has been converted as a road is already a disturbance to the birds,” he says.
The data opens up several possibilities, says team member R. Vridhi. “At a later stage, the avian data will be of great use to study the characteristics of the wetland such as the vegetation, the diet of birds (varieties of fish and microorganisms)…this will help understand why a bird visits a particular lake. Besides the migratory pattern, we observe flying habits, feeding behaviour of birds like Brahminy kite and tailor birds. It is fascinating.”
