Its likely that at very special times of the year its perhaps impressive.
It definitely isn't in February/March (a little surprising).
The guides and rickshaw drivers clearly consider it a lucrative business for them to milk as much tourist money as possible.
The entry fee of 400inr each is grossly excessive and with guides/transport on top.
My recommendation is don't bother.
You start with a 1/2 hr drive to the main area (which you pay for, taking 1hr out of your time). They will show you a few birds (they know exactly what they are and where they will be). Then to the observation area, then back. We were there 2h20min and saw about 20 species of bird, half of which I could find in the UK, and almost all the rest I had already seen (incl owls).
When we finished they wanted payment for 3 hrs (not 2.5hrs) and then demanded (somewhat intimidatingly) a tip on top, which they neither deserved nor got. Why tip someone for doing the barest minimum of his job, who then effectively threatens you?
Try Tamil Nadu for birds (or even the site in Goa), all free and with vastly more species seen closer/better.
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