Which fish is the largest?

   The whale shark (Rhincodon typus, no relation to a whale) is the world's largest fish, weighing as much as 30,000 pounds—more than twice as much as an average elephant—and attaining a length of up to 50 feet. The whale shark is found in the warm waters of the Atlantic, Pacific, and Indian Oceans, where it feeds on plankton through its 5-foot mouth.
   The whale shark moves with the ocean currents that carry plankton, sometimes alone, sometimes in schools of up to 100. Several whale sharks are seen regularly between March and June within the boundaries of the Ningaloo Reef on the western shore of Australia. This gentle species is harmless to human beings. It has been caught for food, especially in Thailand when tuna is scarce, but is increasingly prized alive, as a tourist attraction.