The whale shark (Rhincodon typus) is a slow-moving filter-feeding shark; hence its name — the fish's size is as large as some species of whales and it is a filter feeder like baleen whales. The whale shark is found in open, tropical waters and is rarely found in water below 71°F. In 1829, the whale shark was first described by Andrew Smith, a military doctor associated with British troops stationed in Cape Town, South Africa, after one was harpooned in Table Bay, South Africa.

Related Reading: The Future of Diving With Great White Sharks

Whale sharks have a mouth that can be nearly 5 feet wide, containing 300 to 350 rows of tiny teeth and 10 filter pads which it uses to filter feed. Whale sharks are gray with a white belly, and their skin is marked with pale yellow spots and stripes which are unique to each individual.

• Like the fingerprint of a human, the spot patterns on the flanks of whale sharks are unique. Images of these patterns, taken by divers, are being used to collect vital population data through whaleshark.org.

• Their 300 tiny teeth play almost no role in feeding; instead, special porous pads filter out planktonic crustaceans, small fishes and eggs via a process known as suction filtration.

• The whale shark is most closely related to the nurse, zebra, wobbegong and epaulette sharks. Remarkably, it is the only one that doesn't spend its life resting on the seafloor.

Other interesting facts:

• Whale sharks can be so disturbed by the touch of divers or snorkelers that they violently shudder.

• The whale shark's deepest dives have been recorded over 5,500 feet.

• Whale sharks are the planet's largest living fish. The longest-ever measured was a little longer than a London bus and weighed almost twice as much.

• Whale sharks were scientifically described in 1829, but by 1986, only 320 had ever been recorded. Jacques Cousteau saw only two in his lifetime.

• In 1995 a pregnant female was landed at a Taiwanese fish market carrying 304 pups, confirming live birth in the species. Until this point, no one knew anything about whale shark reproduction.

• The whale shark is listed as endangered on the IUCN Red List of Threatened Species.

• Only 19 whale sharks shorter than 5 feet in length have been reported, the smallest being 15 inches long.

Related Reading: VIDEO Great White Shark Surprises Scuba Divers

Dr. Richard Smith is a pygmy seahorse expert, marine biologist, underwater photographer, scuba diver, and nature and travel writer. To see more of his work, visit Ocean Realm Images.

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