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Red Sea Life - Click
the pictures to enlarge them
| This group of animals is
probably best-known for tyheir hard outer shell. As the animal
grows, this shell must be removed and discarded. Once this takes
place, the new shell takes time to harden. During this period,
the animal is without its primary means of protection and vulnerable
to attack from predators. But they have an impressive arsenal of
weapons at their disposal. The claw of many crustaceans is capable
of exerting hundreds of pounds of pressure. Some even have the
unique ability to produce a deafening miniature sonic boom with
which they stun their prey. The mantis shrimp can even break the
glass of an aquarium or split a man's thumb to the bone with one
strike. But in spite of their impressive armour and fierce weaponry,
the crustaceans do occasionally meet their match. The teeth of
the triggerfish and the beak of the octopus can crack through the
toughest shells of crabs and lobsters, making an enjoyable meal. |
Shrimps |
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To the left is a Fire coral, as the
name suggests, Fire coral can give a nasty sting if touched by
bare skin, due to its stinging nematocyst cells. |
| These are simple animals, lacking a brain
and complex sensing organs. Echinoderms are characterized by their
radial symmetry and a central mouth. Although a sea urchin looks
round, closer inspection reveals that it is nothing more than a
starfish with its legs wrapped inwards to form a sphere. The echinoderms
are found in a stunning variety of shapes and colours, and are
found decorating reefs around the world.
Some of these animals are carnivorous, feeding on corals and
scavenging the ocean floor. Certain species of starfish actually
extend their stomachs into their unwary victims in order to
digest them. The feather stars and sea cucumbers are mainly
filter feeders, catching what ever they can find floating in
the ocean currents. All of the echinoderms move around with
the use of thousands of tiny tube feet, many of which have
suction cups on the ends. Many of the urchins have developed
extremely sharp spines as a means of protection. |
Egyption Starfish (Gomophia egyptiaca) |
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Starfish are carnivores (meat eating) and some are
very clever at getting into shell fish. They have amazing powers
of regeneration and can re-grow lost limbs. |
Pearl Sea Star (Fromia Monilis) |
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This one was fully grown at 10cm. Feeds on detritus
and small invertebrates. |
Tripneustes gratilla Urchin |
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Sea urchins have 5 segments of their outer shell
and are part of the echinoderms species. They are nocturnal animals
commonly found in shallow waters, so they are not seem much during
the day. Their main enemies are the trigger fish who eat
them from their underside.
Urchins eat both plant and animal material. They reproduce
by the simultaneous release of eggs and sperms from the
female and male urchins respectively.
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Diadem Sea Urchin |
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You mostly see urchins during the night and its always
been a mystery to me just where do they all go during the day.
This one has long and fragile spines. |
| Feather Star |
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The feather stars are some of the most primitive
animals in the sea. They have up to 200 arms that have sticky feet
that pass floating plankton into a channel that runs down each
arm to the mouth.
Crinoids prefer to anchor themselves to coral that is exposed
to strong currents where the most amount of floating plankton
drifts by.
They are harmless to humans. |
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Molluscs
comprise a group of soft-bodied animals that includes snails,
clams, and sea slugs. The most common characteristic of most
molluscs is their shell. One of the largest groups, the snails,
is renowned for their shells. Snails are univalves, which means
they have one shell. And it is this shell that for many people
is the epitome of the ocean. There is perhaps no other ocean
treasure that displays more diversity and beauty than the shell.
Conchology
is the name given to the study and collection of shells. The
bivalves, or two-shell molluscs include the clams, scallops,
and oysters. It is the oyster that is responsible for producing
the most coveted of the ocean's treasures - the pearl. Still
other molluscs have lost their shells altogether. The octopus,
the squid, and the sea slugs have evolved their own survival
strategies to replace their protective armour. Indeed, it is
due to the absence of a protective shell the octopus has evolved
the largest and most complex brain of all the molluscs. |
Octopus |
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We stumbled on this octopus during a night dive and
watched it for ages, incredibly it not only changes colour to match
it surroundings but it also seems to change it's texture too. Octopi
hunt primarily at night so its the best time to see them out and
about.
Octopi are very intelligent and can dig its own den and close
the entrance with stones after it is safely inside. During the
day, Octopi usually stay in their dens. which can sometimes be
recognised by the patch of Crab shells at the entrance.
The Octopus feeds on animals such as crustaceans and molluscs.
Once caught, the Octopus bites the victim, injecting a poisonous
venom into their system along with a digestive enzyme. It sucks
the flesh from the crustacean and discards the empty shell.
While the Octopus has very keen eyesight, it is totally deaf. The
female octopus cab lay up to 150,000 eggs in two weeks. Oddly
It does not eat until the eggs hatch in 50 days and many will
die of starvation during this period. |
Squid |
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This little fellow, about 25cm in length was pointed
out to me by Linda Pitkin, a well known photographer. |
Flat worm |
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Spanish Dancer (Hexabranchus sanguineus) |
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This is probably the best know nudibranch (sea slug)
in the Red Sea. As they swim they look just like a Spanish dancer,
hence their name. They are usually about 40cm long. |
Giant Clam |
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The colours of these clams vary and are caused by
an algae that live within the tissues. |
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