Here is another lovely place that is easily doable if you are in Bengaluru or in any of the adjoining states.
Masinaguri In Tamil Nadu is wonderful not only for bird watching but to experience the pure bliss of being amidst nature. From Bengaluru It will be a slightly longish drive, a little over 5 hours if you take the Benagluru Mysore Ooty road. However, the drive is absolutely wonderful because of the areas that you cross on your way, such as Bandipur, Mudumalai...you almost get the feeling of driving through a forest. Almost always in such drives the journeys turn out to be more exciting and invigorating!
These bird pictures (and a couple of animals as well) are from this belt right up to Ooty. The pictures are from my cousin, Soma’s album.