The Forest department is undertaking a scientific bird census at the Biligiriranganathaswamy (BRT) Hills tiger reserve on December 1 and December 2, for the first time in 15 years.

Ornithologists from Karnataka, Andhra Pradesh, Goa and Kerala are taking part in the exercise.

The bird census will be undertaken in the transect method and 20 transect routes (three km each) have been identified in the forest. Two to three teams will conduct the census (on foot) in each of the transect routes. They will analyse diversity of bird species and their density on these routes.

A total of 100 persons, including Forest personnel, ornithologists and wildlife wardens from different districts, will be part of the census. Ornithologists M B Krishna, S Subramanya of Bangalore, V Shantaramu, K Praveen, K Deepu and Prasanna will take part.

The participants will bev given instructions at Kyatadevaragudi on November 30. A total of 274 birds, including 18 that are on the brink of extinction, have been identified in the BRT tiger reserve so far. The last time such an exercise was undertaken was in 1997 by Krishna and Subramanya.

Though several bird experts have undertaken the census in the subsequent years, they were not done scientifically.

The Western and Eastern Ghats meet at the Biligiriranganathaswamy Hills and the tiger reserve is spread over an area of 574.82 sq km. The forest was declared a tiger reserve last year and is home to more than 30 tigers.

The reserve forest extends into the Kollegal, Chamarajanagar and Yelandur taluks and the Gundal, Suvarnavathi reservoirs are located here. Birds, a good number of them from North India, migrate to these reservoirs during winter.

The census will help efforts to save birds on the verge of extinction, BRT project tiger director and forest conservator Vijay Mohanraj told Deccan Herald.