As far as I can tell, there are only a handful of non-marine crustaceans on the island, although some species are quite common. Most species are present throughout the Caribbean.
When hiking in the hills, the sound of falling pebbles is usually made by the Caribbean hermit crab (Coenobita clypeatus) retracting into its shell, falling from wherever it was walking. These colorful crabs have gills rather than lungs, but are still able to respire using the humidity of the air and water kept inside their shell. They are also skilled climbers, able to climb trees and rocky cliffs.
Large burrows in the sand or dirt, often near the coast or salt ponds, are usually the homes of the great land crab (Cardisoma guanhumi), a common species that grows quite large over the course of up to 30 molting cycles.
At the edge of mangroves wetlands, fiddler crabs (Uca pugnax) are quite abundant. Easily identified by their one grossly oversized claw, they typically retreat into the water or into burrows in sand or mud near the shore when approached.
The ghost crab (Ocypode quadrata) gets its name from its translucent shell and can be seen scurrying around sandy beaches amongst the waves where it feeds.
The mangrove crab (Aratus pisonii) and black land crab (Gecarcinus ruricola) are less frequently seen in the open, but often have burrows under rocks or logs where they rest during the day. The black land crab is known locally as the jumbie crab. Jumbies are spirits of the dead and typically considered evil, so this crab is not eaten.