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Spectacular beautiful and busy sea life. Click the pictures to enlarge them
| Crustaceans |
| 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. |
| Echinoderms - starfish, urchins, feather stars, and sea cucumbers |
| 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. |
| Molluscs |
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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. |
| Morays |
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Giant Moray Eel (Gymnothrax javanicus) |
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We watched this moray for some time, we had no idea where its body was, all we could see was its head. The moray is a nocturnal creature and rarely seen free swimming during the day. Although it is not poisonous it is said to have an aggressive personality and some very sharp teeth laden with bacteria.
Giant Morays can reach up to 3m and they don't have scales, instead they are coated with a layer of mucus that protects the skin from germs and parasites.
The Moray has poor eyesight but an excellent sense of smell. Because it hunts at night, the moray needs a keen sense of smell to locate prey such as small fish, crustaceans and the occasional octopus.
A moray must keep its mouth open constantly to take in water so that it can breathe. By opening and closing its mouth , the eel is able to pump water over its gills.
Morays undergo a sex change during growth, changing from male to female. |
Yellow Margin Moray |
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This one has made its home on the foredeck of the Thistlegorm wreck. |
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