Starfish are Echinoderms. Other
members of the phylum are sea urchins, sea cucumbers,
feather stars and crinoids.
The starfish has revolting table
manners. It pushes its stomach out through its mouth,
envelopes its prey and digests it on the spot.
A starfish can get its stomach
through very small openings eg. into the shells of
mussels and other molluscs.
Crown-of-torns starfish feed on
the live polyps of hard corals. 'Plagues' of them have
severely damaged many reefs around the world.
The photograph on the right shows
the familiar colour form of the Crown-of-thorns, as seen
in the Red Sea and on the Great Barrier Reef. The photo
on the left was taken at the Daymaniyat Islands, off the
northern coast of Oman.
Have you seen the
blue and black colour form or any other colour form of
the Crown-of -thorns? If you have, please let me know
through our guestbook.
The photo above
shows a patch of dead coral left behind where the
Crown-of -thorns has been feeding.
The causes of
outbreaks are not known, but there is increasing evidence
that they may be natural phenomena. Fossil evidence of
outbreaks has been found dating back 8,000 years.
Crown-of-thorns has venomous spines that can inflict