Hobbies And Interests
Plankton
The sometimes infinitesimal organisms that float about in the water are called plankton, from the Greek word planktos, which means drifter or wanderer. Plankton are separated into three divisions: Phytoplankton, which covers plants; Zooplankton, the animal plankton; and Bacterioplankton, single-celled bacterial and archael plankton. All these combine to make a nutrient-rich source of food for many ocean dwellers, including some sharks.
Whale Shark
The whale shark, topping out at 40 or more feet, is the largest fish in the sea. It is also one of the gentlest and will sometimes even allow divers to hitch a ride. The whale shark's broad, dappled body is easily recognizable as it swims close to the ocean's surface, mouth stretched wide to pull in its favorite food: plankton. The whale shark is what is known as a filter feeder; it sucks the water and all it contains through its mouth, then expels the water through its gills. What remains -- the plankton, small fish and plants -- is the shark's meal. The whale shark prefers the warm water of the tropical seas and migrates yearly to the continent shelf off Australia's central west coast.
Basking Shark
Another filter feeder, the basking shark, is the second largest fish in the sea. The basking shark swims the arctic and temperate waters of the world and is known by a variety of names, depending on the region. Some of the English names for this behemoth include sun fish, sail fish and elephant shark. The basking shark has an enormous mouth filled with hundreds of tiny teeth, which it holds open as it swims close to the water's surface. Its extended gill slits and gill rakers, which can strain up to 2,000 pounds of water per hour, almost encircle its entire head section, giving this shark a very distinctive look. The basking shark prefers to feed, the majority of the time, in areas where there is a high concentration of zooplankton.
Megamouth Shark
The megamouth is the rarest of the three plankton-feeding sharks. The megamouth shark was only identified in 1976, at which time a new shark species, classification and genus had to be created. Since its discovery, the megamouth shark has only been sighted 49 times as of this writing, in areas of the Indian, Pacific and Atlantic oceans. Though it also is a wide-ranging shark, in comparison to the basking and whale sharks the megamouth is thought to be a less mobile, inferior swimmer.