CHENNAI: The sighting of a globally endangered Indian Skimmer at Illalur Lake near Chengalpattu has sparked fresh calls from conservationists to protect the ecologically fragile Nemmeli-Illalur wetland complex.
Birders documented a lone Indian Skimmer (Rynchops albicollis) at Illalur lake on May 10 between 7.55 am and 8.30 am, marking the only the second confirmed record of the species from the lake and only the 20th documented observation event in the state over the last 11 years. The species is estimated to have fewer than 3,000 individuals globally.
The observation was made by birders Ravichandran, I Abinesh and Madhan. According to the observers, the bird was seen foraging in knee-deep water amid extensive mudflats exposed by low water levels at the lake. “We assume skimmers and other pratincoles chose the site because of the extensive mudflats available for roosting and foraging. These mudflats should not be removed in the name of future lake restoration,” the group said.
Illalur lake, located adjacent to the Nemmeli coastal wetland, has long served as a seasonal habitat for several waterbirds including Small Pratincole, Little Ringed Plover, Black-winged Stilt, Spot-billed Duck and Fulvous Whistling Duck. Birders say the lake’s exposed mudflats and shallow waters create ideal stopover conditions for migratory birds along the Central Asian Flyway.
The latest sighting comes amid growing concerns over the proposed Mamallan Reservoir project, which conservationists fear could alter the hydrology of the wetland complex. Illalur and Nemmeli are hydrologically connected and lie barely 4 km apart. “Destroying or altering one wetland will affect the entire connected ecosystem,” said Deepak Venkatachalam, founder of Suzhal Arivom, a grassroots nature conservation group.
Data compiled from eBird records show Indian Skimmer sightings in Tamil Nadu are exceptionally rare. Only 19 observation events were documented between 2015 and 2024, with 89% of sightings recorded at Pulicat lake. Six of those years had zero sightings.
Conservationists also pointed to the degradation of the nearby Sirudavoor wetland as a warning. Once known for grasslands and mudflats used by migratory raptors and pratincoles, the site reportedly lost its ecological value following sand mining and habitat modification. “This record is an indicator of the ecological health and international importance of these wetlands. Protecting wetlands means protecting entire migratory pathways,” said another member of Suzhal Arivom.
The Suzhal Arivom recommends declaring the Illalur-Nemmeli wetland complex an Important Bird Area and initiating long-term monitoring to document migratory bird usage.