Coconut Crabs

Have you always dreamed about being marooned on a beautiful island, which has gentle swaying coconut palms and only the green environs for company? Well, if this is your dream then you need to think again! You might not be the only one who is craving for solitude and for cool refreshing coconut water! Don’t be surprised to find that a coconut crab beats you to the best coconut you may have just spotted! Yes! Coconut crabs also love coconuts as much as we do and they have a wide variety of names that have been given to them due to their certain characteristics. Here’s a look at coconut crabs and details about their daily life and behavioral patterns.

Coconut Crabs: Description and Distribution
The coconut crabs are also known as the robber crabs, palm thief (rumored to have stolen shiny objects), terrestrial hermit crab and is also known locally as ayuyu and unga. The coconut crab is also the only of its species that belong to the genus Birgus. Coconut crabs are found in areas around the Indian Ocean and central areas of the Pacific Ocean. They generally occur in the Seychelles, Astove Island, Aldabra, Glorioso Islands and even on the Andaman and Nicobar Islands.

The characteristic feature of the coconut crab is the strong pincers and this is what enables it to crack coconuts as well! Hence the name coconut crabs. The coconut crab has 8 legs and it is the front legs that have the large claws, which are used to open coconuts. The next two pairs of legs have claws that give it the freedom to climb coconut trees. The next pair of legs has different uses. The last small pair of legs is used to clean the breathing organs. An adult coconut crab can have a length of 1 m for the leg span. The body length in these cases can go up to 40 cm. They weigh around 17 kg on an average.

The coconut crab is related to the hermit crab, but in case of the coconut crabs, it is only the young crabs that use shells to protect themselves. Sometimes, broken shells of coconut are also used as a form of protection. Shells are also used when the crab is going through the stage of moulting. This phase can last for around 30 days.

Coconut crabs also have another distinctive feature with regards to their body- the nose! As opposed to other crabs that live in the water, coconut crabs live on the land therefore they have differently structured organs on their body, which resembles those seen on insects. They have aesthetascs on their antennae and these enable the coconut crabs to have an excellent sense of smell.

Coconut Crabs: Diet and Food Habits
Coconuts are obviously high on the list of favored food items for the coconut crabs. The coconut crabs consume fruits, leaves, tortoise eggs and even shells of other animals. As mentioned earlier, the coconut crabs use their strong claws to make holes into the coconut shells. They use these claws to break the coconuts into smaller pieces so that it can be eaten easily.

Coconut Crabs: Behavior Patterns
Rumors have always been rife about the coconut crabs having the tendency to steal pots and silver ware from the houses of many. They are also known to live underground and are also found in the rock crevices. These crabs also use the coconut husk in their burrows to provide comfortable bedding! It is known to eat the coconuts on the trees but there are times when the crab may cut it in such a way, the coconuts tend to fall to the ground. The coconut crabs are nocturnal creatures and this is time when they go in search of food. The highly developed sense of smell helps it to locate rotting food or fruit, which may be really far away from its actual location.

Coconut Crabs: Breeding Patterns
The coconut crabs mate during the months of May to September. During the mating period, the male and the female coconut crabs are known to fight with each other. The females release the eggs into the sea at the time of hatching when there is a high tide. The hatching period occurs in the months of October to November. It is only in their initial stages that the young crabs live in the water and change shells. They leave the oceans after a month once they develop their ability to live on land. This is the time when coconut shells are used for protection till the hard abdomen is developed.