The mantou crabs of Puerto Rico find home under the shade of mangroves and manchineel trees. They bore holes into the white sand, building tunnels that follow the contours of the tree roots. The younger crabs are of deep brown color with bright red pincers. As they grow older and molt, their carapace turns yellow, dull blue, or gray–a perfect camouflage in this sandy environment.
When approached, the crabs scurry back into the hole, half hidden inside but pinchers ready if attacked. The slower crabs however fall prey to the yaboa heron. The heron, with its lanky legs as hunting platform and a pitcher’s neck coiled almost like a spring, use its pointed beak to stab through the thick carapace, leaving a trail of crab body parts in its path.
Of course, the top predators of the mantou crabs are humans as the crustaceans often appear in the menu of many restaurants and hotels. Along the roads of Puerto Rico, for example, one finds live mantou crabs placed in a chicken wire cage or strung together and hung on a pole.
In Punta Santiago, I was told that crab hunting occurs right by the road side at night. Shovel and flashlight in hand, crab hunters stalk these crabs and pull them out of their holes. The population of this species in the Caribbean are in decline primarily due to habitat destruction and pesticide use. In Martinique and other areas of the Caribbean, short and long-term banning of crab hunting and trapping have been strictly enforced to save the species.
The chance of the species’ survival however seems bright. One time, while walking along Punta Santiago, I chanced on a mating mantou crab. Right by the sandy beach, littered with dead sea grass and driftwood, the crabs stood transfixed, one on top of the other as if in a tight embrace. The middle part of their ventral shell opened like a medieval drawbridge, literally opening one’s shell for the other. For anything, the mantou crabs can bring forth thousands of eggs to the sea. Afterall, their reproductive organs are just right under their hearts.
Pictures of crab species in Puerto Rico