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WHale Shark
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| Photo Information |
Copyright: Thomas Sautter (mjdundee)
![Gold Star Critiquer/Gold Note Writer [C: 76 W: 0 N: 287]](http://i1.treknature.com/misc/g-n-g.gif) (1207) |
| Genre: Animals |
| Medium: Color |
| Date Taken: 1998-04 |
| Categories: Fish |
| Photo Version: Original Version |
| Date Submitted: 2005-12-11 9:40 |
| Viewed: 1729 |
| Points: 2 |
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| [Note Guidelines] Photographer's Note |
I have to admit that ths photo is not a real good one but for a species as rare as this I think it is worth posting it together with some information about the worlds largest fish. I took it 2 boat hours off the coast at Coral Bay after a plane has spotted it and advised the coordinates to find it drifting slowly and close to the surface. The guide estimated it a 15 m shark - the largest she had ever seen. I could follow him for about 10 minutes before he disappeared deep into the blue. The photo was taken with a 'film with lens' underwater oneway cam.
Information from: wikipedia
A member of the order Orectolobiformes, it is a filter feeder. The shark has a capacious mouth which can be up to 1.5 m (5 ft) wide and contain up to 300 rows of tiny teeth. As part of its feeding process, it also has five large pairs of gill arches. Two small eyes are located towards the front of the shark's wide, flat head. The body is mostly grey with a white belly; three prominent ridges run along each side of the animal and the skin is marked with a 'checkerboard' of pale yellow spots and stripes. The shark has two pairs each of dorsal fins and pectoral fins. A juvenile whale shark's tail has a greater top fin than lower fin while the adult tail becomes semi-lunate, or crescent-shaped. The shark's spiracles are just behind the eyes. The whale shark is not an efficient swimmer; the entire body is in motion while the animal swims. The result of this motion, one that is very unusual for sharks, is an average speed of around 5 km/h.
Diet
A diagram of the Whale sharkThe whale shark feeds on phytoplankton, macro-algae, plankton, krill or nektonic life (small squid or vertebrates). The many rows of teeth play no role in feeding, instead, water is actively drawn into the mouth and is passed over gill rakers and then out through the gill arches. Any material caught in the rakers is swallowed. The shark can circulate water at a rate up to 1.7 L/s (3.5 US pint/s). The sharks, however, are active feeders and target concentrations of plankton or fish by olfactory cues rather than simply 'vacuuming' constantly.
Behaviour
When it is explained that not all sharks are dangerous to humans, this species is used as the leading example. Nature documentaries frequently show footage of divers keeping pace with the giant fish, and the shark pays them no mind. The whale shark is often seen by divers while feeding, it is very popular to have special whale shark dive/snorkel trip in places like Nigaloo reef in Western Australia. It is often seen by divers in Thailand, The Maldives, The Red Sea and at the Galapagos islands. |
lebjohnson has marked this note useful
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very good note, and interesting indeed, yes it must be such a great feeling to see such a huge moonster of our seas. Well just glad its not a nasty shark. Well done Anyway and thanks for sharing this interesting info and photo.
Demetrio
