Sri Lanka, Nov. 19 -- Sri Lankan researchers have, for the first time, documented the presence of two rare free-tailed bat species Wroughton's free-tailed bat (Otomops wroughtoni) and the East Asian free-tailed bat (Tadarida insignis) using advanced acoustic monitoring in tea plantations across the island.

Because bats fly high and are active at night, they are often difficult to observe. Acoustic surveys allow scientists to detect and identify species through their unique echolocation calls. The calls recorded in the study were clearly different from those of other bat species known in Sri Lanka, confirming the presence of both O. wroughtoni and T. insignis.

The discovery marks a major expansion in understanding bat diversity on the is...