See, you don't need to go deep into the sea to spy on sea creatures.
The Turneffe Atoll is home to a very healthy hermit crab population. Some are small, like this little fella – hardly bigger than a golf ball, in fact. While others are about the size of a small dog and look like they were hatched on an Alien film set.
Keep an eye out as you walk around at night – hermit crabs are everywhere when the sun goes down – and have a look around the base of palm trees and bushes; you may see 10 or 20 huddled together at one time in an effort to escape the midday sun.