This place is one of the four geological monuments in Karnataka State an apparently high on eco tourism. The rocks are basaltic rock formation in a hexagonal form which is the only type in the country. Small island, barely 1/2 a km across an pushing 100 – 150 m length wise, you can cover the area quite well. Also called Coconut Island.
Unlike earlier where there was no provision for anything, I did find people selling soft drinks / water on the island. But take your own to be safe. Check out wikipedia for some more info or ourkarnataka.com.
There ya have it!