Flora and fauna
As of June 2016 entry to the park cost 450 rupees for non-Indians. Activities are extra.
The 90 minute boat ride costs 225 rupees. Various trekking options are available. For example, the Nature Walk and the Green Walk both cost 300 rupees per person, although there is a minimum charge of 1200 rupees (so, to pay only 300 rupees per person, you'll need to be in a group of at least 4).
Be aware that leeches are likely to attach themselves to your leg if you go an a bushwalk with one of the guides. Special canvas 'shoe covers' are available. Do not wander in the woods alone.