Mannar wind power plant kills more birds than predicted, says EIA report

More bird collision incidents have been reported than that were predicted at the Thambapavani wind power plant, though it is equipped with the latest radar technology to detect flying flocks and shut down the turbines, according to the EIA report on the second phase of the project.

"In the case of the Thambapawani Wind Power Project, higher bird collision risks than predicted have occurred, as there are reported bird collisions in the transmission lines,” the report said, indicating that as the proposed project is spread over a large area, possible localised conditions may change the predicted bird collision risks in the future.

As per the post-construction monitoring of the 30 wind turbines in the first phase of the project and the transmission line segment that traverses through the Vankalai Sanctuary, 376 carcasses were found during the period from September 2021 to March last year, the report noted.

The 235 carcasses found on the transmission line were much higher than the 139 carcasses found at the wind farm, the report said.

Of these, 322 (86%) carcasses were identified up to the species level. Out of the remaining 54 carcasses, 32 were identified up to the genus level, while the remaining 20 carcasses could not be identified as only partial remains were found, the report noted.

Altogether, 44 species of birds and two species of bats were identified. Of the 139 carcasses recorded at the wind farm, only four bat carcasses—one megachiropteran and three microchiropteran—were identified.

Mannar Island is home to thirty percent of the country's birds, with more than 150 species, and the region generally harbours more than 200,000 water birds during the migratory season as the Gulf of Mannar region forms a part of the Central Asian Flyway. When leaving the country at the end of the migratory season, the migrant birds use this region as their last staging point before departure.

The proposed project is surrounded by three protected areas: Adams Bridge National Park, Vidataltivu Nature Reserve, and the Ramsar site of Vankalai Sanctuary.

However, the report stressed that none of the turbines are located within any of the protected areas, “but some of the proposed locations of the wind turbines are within the 1.6 km buffer zones of these protected areas."