What are Sponge Crabs

The orange brown sponge crab is certainly a unique crab. With small black eyes and a broad hunched shell, this crab certainly has character. Known for carrying sponges on their backs, hence the name, these critters get by by decorating themselves. This is the creatures main defense, though its mighty claws come in second.  He places the sponge on his back to look like his surroundings. What is remarkable about this action, is the animals ability to mold the sponges shape to make it like a second shell. The sponge is simply taken into the claws of the crab and pinched to fit. Then as the crab gets even larger, so does the living sponge, and it becomes a permanent fixture.

These crabs spend their days mostly scavenging about on the reefs. Since they are mostly nocturnal, hunting is generally done at night.  As a pet, or feature in an aquarium, this animal is labeled as semi-aggressive. It is pertinent that such a species not be kept with other creatures that could hurt it, including others of its kind. Like other crabs, this critter eats whatever it can get. It prefers meaty food like mussels or shrimp but will eat the leftovers of other fish if necessary. Because of these specifications, only certain aquariums could house sponge crabs. Ideally they would have plenty of space, and no other competitive predators that could influence their health.

Known in Latin as “Dromidaee”  this is a family of crab all related by the strange ability to mold sponges to their shell. Some crabs of this family appear extremely pale beneath their sponges, with small pink eyes that peer just below their shells. Others are larger, with a golden to orange hue and larger claws. Some are simply gray colored. It all depends on the environment they live in and the type of sponge that they will have to camouflage themselves with. An orange crab would never survive with a white sponge and a white crab could never put on a white sponge. This behavior was developed for the creature’s survival, so it is fitted to individual environments because of adaptation. 

Maybe one of the most interesting crabs of them all, sponge crabs have developed over time with precision and care. They survive due to their unique adaptation. The sponge on their back, which protects them visually, and physically from harm makes them unique and durable as a species.