As you can see, it's a desert here.
A 'blowhole' -- a cave in the rock that would fill with water as the waves rolled in, then made sort of a geyser as it blew out.
This is the east shore of the island. The winds come from the east here, so this side of the island gets beat by the waves. The west shore is the 'lee' side of the island, where the calm waters and protected coral reefs are.