Coral and Crab Trade Services

Tiny crabs living in the South Pacific provide regular cleaning "services" that may be critical to the life of coral reefs around the world, a new study suggests.

Coral provide a home and protection for the crabs. In turn, the crabs provide "housekeeping" duties for the coral, routinely "sweeping" out sediment that falls onto the coral. Therefore, the relationship between the corals and the trapeziid crabs is mutually beneficial, or symbiotic, researchers report.

"Although we don't know much about these crabs, we do know that they are 'picky,' and are always tasting and exploring," said lead study author Hannah L. Stewart, a researcher at the University of California, Santa Barbara. "They use their front appendages to manipulate and shovel out the sediment."

The accumulation of sediment on coral tissue is known to reduce metabolic and tissue growth rates of coral, increasing the probability of bleaching and coral death. Many corals can remove some sediment from their surfaces but high sediment loads can be deadly.

-- LiveScience Staff

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Credit: Hannah Stewart, UCSB