Whale shark

Estimated population:

Unknown. The whale shark is considered vulnerable by the IUCN.

Ways to identify this species:

Whale sharks are grayish-brown with a white underbelly and white spots and lines. This species is the largest fish in the world measuring 20 - 55 feet in length. Whale sharks are usually seen in the open water.

Biology

• Believed to have originated 60 million years ago, whale sharks are found in tropical and temperate waters worldwide at depths up to 100 feet.


• This species is a filter feeder and sieves plankton through its gills as it swims. It also feeds on fish, squid, and pelagic crustaceans by opening its huge mouth.


• Whale sharks have 5 large gill slits and the first gill slit (spiracle), which is used for breathing when the shark is resting on the sea floor, is located directly behind the shark's eye.


• This species can weigh up to 15 tons, and like most sharks, females are larger than males.


• Whale sharks have about 3,000 tiny teeth, which are of little use.


• This shark can process >1,500 gallons of water each hour.


• Whale sharks are solitary species but at 30 years they begin mating.


• This shark can live to an age of 100 - 150 years.