It is possible to hire a boat & sail around this island group from the very pretty fishing village of Charlotteville -but there is no landing facility.
These islands hold the local breeding colony of Magnificent Frigate Birds as well as various other seabirds including Bridled & Sooty Terns. Brown Noddies, three species of Booby (including a few pairs of Masked Boobies) and Tropicbirds.
This report includes an account of the St Giles boat trip: http://www.birdtours.co.uk/tripreports/trinidad/tobago2/tob-nov-03.htm