Birds, mammals stay away from ‘noisy windmills’ 

Compared to fossil fuel, wind energy wreaks less destruction on the environment, but in the State many wind turbines have come up in forest areas, often at the cost of its denizens.

A study, by the Salim Ali Centre for Ornithology and Natural History (SACON), has found that apart from direct impact, noise and vibrations from the blades were driving away animals, thereby increasing the possibility of man-animal conflict.

The study was necessitated by the growing number of windmills in forest areas whose impact has, till now, not been studied or included in policy.

Karnataka’s investment in wind energy has seen 37.8 sq.km. of forest land being diverted for wind farms, according to Ministry of Environment and Forests (MoEF) data. These numbers have risen in recent years with more policy thrust towards “green” energy.

Karnataka Renewable Energy Development Limited (KREDL) states that there are more than 3,857 wind turbines dotting the State’s hills, generating 4,730 MW of electricity.

As many as 11 researchers, led by H.N. Kumara from SACON, spent over a year monitoring windmills in Chitradurga (Jogimatti forests being a hub) and Gadag (including Kappatagudda which was recently declared as a sanctuary).

They recorded that between 35 to 40% of the State’s bird diversity reside in and around these areas.

The team enumerated collisions of 10 animals, six bats and four birds, representing a rate of 0.23 animals per wind turbine annually.

While the rate was on the “lower side” compared to other locations in the country, the issue cannot be ignored as most collisions happened in the short time during the post-monsoon period, states the study.

However, these numbers also hide a larger concern: birds are actively avoiding windmill sites.

“There is a clear displacement of birds. We estimate that there are 50% lesser birds in areas with windmills compared to control sites nearby that were undisturbed,” says Dr. Kumara.

This avoidance is seen in mammals too which was studied based on the directions of the Forest Department.

Using camera-traps in Kappatagudda, researchers found that some species, particularly antelopes, have actively avoided areas with windmills.

“This area is perhaps the only place in the State where three types of antelopes are found: four-horned, chinkara, and blackbuck. They are moving away from windmills and towards the forest fringes. Following them are predators such as wolves and small carnivores…this is bound to increase man-animal conflict,” says Dr. Kumara.

However, there has been no impact on certain small herbivores, such as hares, for whom these predator-free patches represent safety. This is consistent with an ongoing Indian Institute of Science study which shows that lizards prefer patches with windmills due to the lower predator densities.

These observations are being studied by the Forest Department which is compiling man-animal conflicts in the area over the past 15 years. However, with the department sending clarifications and comments, the final report is expected to be submitted by the end of the month.

“We have asked for certain refinements, and we will look seriously at the impact of windmills on birds and mammals. Based on this, we will draw up guidelines for setting up windmills to mitigate these effects,” said C. Jayaram, Principal Chief Conservator of Forests (Wildlife).