Chemical may deter starfish from devouring endangered coral reefs

December 16, 2000

Click here for abstract 1 and here for abstract 2:

HONOLULU, Dec. 17 - Researchers have discovered a chemical in sea urchins that might be used to lure starfish away from coral reefs, an endangered ecosystem they are devouring at an alarming rate. The finding was presented here today during the 2000 International Chemical Congress of Pacific Basin Societies.

The weeklong scientific meeting, held once every five years, is hosted by the American Chemical Society, in conjunction with its counterparts in Australia, Canada, Japan and New Zealand.

The poisonous crown-of-thorns starfish, which feasts on coral and whose population is believed to be expanding, is a major source of destruction of valued habitats in the tropical zones of the Indian and Pacific oceans, including Hawaii. The problem is acute in Japan, where extensive, costly efforts to control the creature have met with little success.

Home to a variety of organisms that are a potential source of life-saving medicines, coral reefs have been called the rainforests of the sea. These rich ecosystems are rapidly disappearing. An estimated 27 percent of the world's coral reefs have already been destroyed, according to the Global Coral Reef Monitoring Network, an organization established to assess and improve reef conditions. Unless better management is established, 40 percent of the world's reefs will be lost by 2010, the network predicts. Starfish are expected to be a significant factor in this decline.

Researchers at Nagoya University in Nagoya, Japan, recently discovered that sea urchins contain a chemical that appears to attract starfish. After laboratory analysis, they isolated the active chemicals from the urchin and found they are two unsaturated fatty acids: arachidonic acid and a-linolenic acid.

While only a small number of starfish were captured during an initial trial of the attractant, the results are promising because they represent proof of principle, says Daisuke Uemura, Ph.D., the study's lead researcher and a chemistry professor at the university.

"Although we can't save all of the coral reefs in the world from destruction, our research is useful for saving some of them," says Uemura.

Most attempts to control the starfish population have been unsuccessful. Poisoning harms other creatures that share their habitat. Cutting them up is compromised by the ability of starfish to regenerate whole organisms from severed parts. Other methods include catching the creatures with a harpoon and isolating the adults from coral with underwater fences. Methods under consideration include the introduction of diseases and predators that are specific to the starfish.

No one is certain why outbreaks of starfish appear to have increased in recent years. One theory suggests that their populations bloom several years after a large typhoon with high rainfall, which produces abundant sediments. These sediments are thought to contain nutrients that contribute to plankton blooms, which serve as food for young starfish. Other theories point to the destruction of their major predators and the effects of pollution.

Besides starfish, many other forces play a major role in the destruction of the reefs. These include overfishing, pollution, typhoons and global warming. In Hawaii, where most of the coral reefs in the United States are found, coral is being decimated by tourists, particularly snorkelers.

More than 8,000 research papers will be presented during this year's International Chemical Congress, which is sponsored jointly by the American Chemical Society, the Chemical Society of Japan, the Canadian Society of Chemistry, the Royal Australian Chemical Institute and the New Zealand Institute of Chemistry.
-end-
The paper on this research, ORGN 850, will be presented at 8:40 a.m., Sunday, Dec. 17, at the Hilton Hawaiian Village, Coral Ballroom I, Mid-Pacific Conference Center, during the symposium, "Natural Products of Chemistry: Biological Activity and Synthesis." In addition, a poster on this research, ORGN 1277, will be presented at 9:00 a.m., Monday, Dec. 18, at the Hilton Hawaiian Village, Coral Ballroom III, Mid-Pacific Conference Center, during the same symposium.

Daisuke Uemura is a professor in the department of chemistry at Nagoya University in Nagoya, Japan.

American Chemical Society

Related Coral Reefs Articles from Brightsurf:

The cement for coral reefs
Coral reefs are hotspots of biodiversity. As they can withstand heavy storms, they offer many species a safe home.

Palau's coral reefs: a jewel of the ocean
The latest report from the Living Oceans Foundation finds Palau's reefs had the highest coral cover observed on the Global Reef Expedition--the largest coral reef survey and mapping expedition in history.

Shedding light on coral reefs
New research published in the journal Coral Reefs generates the largest characterization of coral reef spectral data to date.

Uncovering the hidden life of 'dead' coral reefs
'Dead' coral rubble can support more animals than live coral, according to University of Queensland researchers trialling a high-tech sampling method.

Collaboration is key to rebuilding coral reefs
The most successful and cost-effective ways to restore coral reefs have been identified by an international group of scientists, after analyzing restoration projects in Latin America.

Coral reefs show resilience to rising temperatures
Rising ocean temperatures have devastated coral reefs all over the world, but a recent study in Global Change Biology has found that reefs in the Eastern Tropical Pacific region may prove to be an exception.

Genetics could help protect coral reefs from global warming
The research provides more evidence that genetic-sequencing can reveal evolutionary differences in reef-building corals that one day could help scientists identify which strains could adapt to warmer seas.

Tackling coral reefs' thorny problem
Researchers from the Okinawa Institute of Science and Technology Graduate University (OIST) have revealed the evolutionary history of the crown-of-thorns starfish -- a predator of coral that can devastate coral reefs.

The state of coral reefs in the Solomon Islands
The ''Global Reef Expedition: Solomon Islands Final Report'' summarizes the foundation's findings from a monumental research mission to study corals and reef fish in the Solomon Islands and provides recommendations on how to preserve these precious ecosystems into the future.

Mysterious glowing coral reefs are fighting to recover
A new study by the University of Southampton has revealed why some corals exhibit a dazzling colorful display, instead of turning white, when they suffer 'coral bleaching' -- a condition which can devastate reefs and is caused by ocean warming.

Read More: Coral Reefs News and Coral Reefs Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.