Sea cucumbers could be key to preserving coral reefs

January 31, 2012
Sea cucumbers, such as this Stichopus Herrmanni, can counter the negative effects of ocean acidification through their natural digestive processes

(PhysOrg.com) -- Tropical sea cucumbers could play a key role in saving coral reefs from the devastating effects of climate change, say scientists at One Tree Island, the University of Sydney's research station on the Great Barrier Reef.

"We have found that sea cucumbers play a vital role in reducing the harmful impact of ocean acidification on coral growth," said Professor Maria Byrne, the director of One Tree Island Research Station.

"When they ingest sand, the natural digestive processes in the sea cucumber's gut increases the pH levels of the water on the reef where they defecate, countering the negative effects of ," said Professor Byrne.

One of the by-products of the sea cucumber's digestion of sand is calcium carbonate (CaCO3) a key component of coral. To survive, coral reefs must accumulate CaCO3 at a rate greater than or equal to the CaCO3 that is eroded from the reef.

"The research at One Tree Island showed that in a healthy reef, dissolution of calcium carbonate sediment by sea cucumbers and other bioeroders appears to be an important component of the natural calcium carbonate turnover," said Professor Byrne.

"The ammonia waste produced when sea cucumbers digest sand also serves to fertilise the surrounding area, providing nutrients for coral growth," she added.

The research, recently published in the Journal of Geophysical Research, was carried out by an international group of scientists from the University of Sydney, the Carnegie Institute for Science, Stanford, and several other institutions studying the impact of climate change on .

Sea cucumbers are among the largest invertebrates found on . Some 30 species are commercially harvested by the fishery industry along the and throughout the tropics.

"We urgently need to understand the impact of removing sea cucumbers and other invertebrates on reef health and resilience at a time when reefs face an uncertain future," Professor Byrne said.

Explore further: Ancient Australian reef raises hopes for coral as seas warm

Related Stories

Increased acidity not an even test for coral reefs

November 10, 2011

Coral reefs can both positively and negatively influence the acidity of their surrounding seawater. That is the take-home message of two papers recently published in the international journal Global Change Biology, by a group ...

Sea cucumbers: Dissolving coral reefs?

December 22, 2011

Coral reefs are extremely diverse ecosystems that support enormous biodiversity. But they are at risk. Carbon dioxide emissions are acidifying the ocean, threatening reefs and other marine organisms. New research led by Carnegie's ...

Recommended for you

Earth's mineralogy unique in the cosmos

August 26, 2015

New research from a team led by Carnegie's Robert Hazen predicts that Earth has more than 1,500 undiscovered minerals and that the exact mineral diversity of our planet is unique and could not be duplicated anywhere in the ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

Howhot
not rated yet Jan 31, 2012
On a coral reef dive, I saw one of the creatures. Amazing. Just jaw dropping how colorful they are.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.