From uduppi railway station travel to uduppi bus stand by taking an auto .and from their travel by bus to Malpe .
From Malpe harbour govt owned boats do service to St marys island and From malpe beach private boats services are also available
Govt owned boats are larger than private boats and they start service only if minimum of 30 passengers are available .Charge (rs 250/- per head to and fro as of september 2018) .also upon nearing the island the passengers need to change to small boats to get down at the island .
private boats are smaller boats and starts operation if minimum of 10 passengers are available (charge rs 300/- per head as of september 2018) No need to change to other boat during the journey .
By evening 5 PM you have to return back anyhow as no stay at night time is allowed in the island.
PS: Boat services will be temporarily shut down during monsoon (june – 15th september most probably)and when the sea is rough . so please do confirm early whether the service is open before you make your plan