02 October 2008

Four Crown-of-thorns sea star species and not just one

Notorious as predators of hard corals, DNA analysis shows this sea star comprises four distinct species.

Different species could favour different habitats and have different reproductive and nutritional behaviours, and this in turn could dictate when and where Crown-of-thorns outbreaks occur. But further investigation is needed to see if this is the case.

It behooves me to clarify before plunging into the article that Crown-of-thorns are only devastating to reefs where there is a population explosion of them. In 'normal' situations, these sea stars do not cause massive damage. Scientists are still trying to better understand the causes of Crown-of-thorns outbreaks.

The notorious reputation of the Crown-of-thorns has led some people to believe that ALL sea stars are bad for the reefs. See this comment on the Me(w)andering blog. The Crown-of-thorns sea star has NOT been recorded for Singapore waters.

Coral-killing starfish turns out to be four species, not one
Yahoo News 30 Sep 08;
The crown-of-thorns starfish, a notorious threat to coral in the Indian and Pacific Oceans, comprises four species, not one, biologists reported on Tuesday.

The spiny predator, known by its Latin name of Acanthaster planci, has been a worsening peril to reefs for at least three decades, latching onto coral polyps and digesting them.

A paper published in the British journal Biology Letters said that most research on A. planci has been carried out on in the Pacific, triggered by devastating outbreaks of the pest on Australia's Great Barrier Reef.

But DNA analysis of specimens recovered elsewhere shows the creature comprises four distinct species, it says.

They are found in the Red Sea, the Northern Indian Ocean and the Southern Indian Ocean as well as in the Pacific.

The surprise finding could have important consequences for reef conservation, say the authors.

Different species could favour different habitats and have different reproductive and nutritional behaviours, and this in turn could dictate when and where starfish outbreaks occur. But further investigation is needed to see if this is the case.

The paper is lead-authored by Gert Woerheide of the Georg-August University in Goettingen, western Germany.

No comments:

Post a Comment

LinkWithin

Related Posts with Thumbnails