The whale shark was declared Western Australia's marine emblem on November 12th 2013.
Whale sharks are large harmless members of the shark family that regularly visit the area near Ningaloo Reef. They are the world's largest living fish growing to between
15 and 18 metres in length on a diet of plankton. Most whale sharks that visit Ningaloo are juvenile males between 3 and 12 metres long.
Each shark has a unique pattern of spots that scientists use to identify individuals when they are being studied.
Ningaloo is one of the best places to see whale sharks and is very popular with scuba divers. In March and April the full moon triggers spawning of corals and this attracts
large numbers of whale sharks to the area.
The sharks engage in what is called 'passive feeding' which means they simply swim through the water with their mouths open and collect the plankton that happens to be
in the water they filter. They also employ active feeding by forcefully pumping water through their gills. They have been seen hanging vertically in the water gulping in
plankton rich brine.
Despite the studies that have been done into whale sharks, there are still many questions that need answering. How far they travel, when and where they mate, how many
young are born and many other important aspects of their lives remain unknown.
They are protected in W.A. by law but they are being killed off by Indonesian fishermen and may be wiped out if international pressure isn't brought to bear to stop the
killing. Internationally the species is regarded as vulnerable and their numbers are declining. If you go boating in areas where whale sharks visit, it is important to post a
bow watch to ensure that you do not run into them with your boat. They feed near the surface and are prone to being struck by propellers and boat hulls and this should be
avoided at all costs.
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