The Basking Shark Fish

Occasionally known as "sunfish" or "sailfish" in certain areas of the world, the basking shark is the only member of the family Rhetorician. It was first described by Gunnerus in 1765 from a specimen from Norway and was originally assigned the name Squalus maximus. Synonymous names include Squalus isodus Macri 1819, Squalus elephas Lesueur 1822,Squalus rashleighanus Couch 1838, Sqalus cetaceus Gronow 1854, Cetorhinus blainvillei Capello 1869, Selachus pennantii Cornish 1885, Cetorhinus maximus infanuncula Deinse & Adriani 1953 and Cetorhinus maximus normaniSiccardi 1961). The currently accepted scientific name is Cetorhinus maximus as assigned by Gunnerus in 1765. The genus name Cetorhinus is derived from the Greek, "ketos" = a marine monster, whale and "rhinos" = nose while the species name maximus is Latin, meaning "great." The basking shark is a coastal-pelagic species found throughout the world's arctic and temperate waters. In the western Atlantic, it ranges from Newfoundland to Florida and southern Brazil to Argentina and from Iceland and Norway to Senegal, including the parts of the Mediterranean in the eastern Atlantic. It is found off Japan, China and the Koreas as well as western and southern Australia and the coastlines of New Zealand in the western Pacific and from the Gulf of Alaska to the Gulf of California and from Ecuador to Chile in the eastern Pacific. The basking shark is typically seen swimming slowly at the surface, mouth agape in open water near shore. This species is known to enter bays and estuaries as well as venturing offshore. Basking sharks are often seen traveling in pairs and in larger schools of up to a 100 or more. Its common name comes from its habit of 'sunning' itself at the surface, back awash with its first dorsal fin fully exposed. Basking sharks are highly migratory. Off the Atlantic coast of North America it appears in the southern part of its range in the spring (North Carolina to New York), shifts northward in the summer (New England and Canada), and disappears in autumn and winter. Off the southwest coast of the United Kingdom in the northeast Atlantic, the basking shark feeds at the surface of coastal waters during the summer. These sharks are absent from November to March, suggesting a migration beyond the continental shelf during the winter months. This is explained by the high zooplankton density (the primary food of the basking shark) that exists in these waters during late spring and early summer. Sightings of groups of individuals of the same size and sex suggest that there is pronounced sexual and population segregation in migrating basking sharks. Along with the whale shark and the megamouth shark (Megachasma pelagios), the basking shark is one of three species of large, filter-feeding sharks. However, the basking shark is the only one that relies solely on the passive flow of water through its pharynx by swimming. The basking shark is usually seen swimming with its mouth wide open, taking in a continuous flow of water. The whale shark and megamouth shark assist the process by suction or actively pumping water into their pharynxes. Food is strained from the water by gill rakers located in the gill slits. The basking shark's gill rakers can strain up to 2000 tons of water per hour. These sharks feed along areas that contain high densities of large zooplankton (i.e., small crustaceans, invertebrate larvae, and fish eggs and larvae). There is a theory that the basking shark feeds on the surface when plankton is abundant, then sheds its gill rakers and hibernates in deeper water during winter. Alternatively, it has been suggested that the basking shark turns to benthic (near bottom) feeding when it loses its gill rakers. It is not known how often it sheds these gill rakers or how rapidly they are replaced. 

he basking shark gets its name due to being slow moving and enjoying time basking in the sun. It is strange to researchers to see such a large shark so close to the surface though. The basking shark is the second largest shark found in the world. They do move to deeper water in the winter months though.Sometimes the basking shark is seen jumping out of the water. It is an amazing sight to see due to the sheer size of them. Researchers believe this is done in an effort to remove as many parasites from the body as possible.It has an extremely large liver, bigger than most species of sharks. The liver is believed to be ¼ of the overall body weight. This liver not only stores oil to help reduce the need to feed but it allows the basking shark to have plenty of energy all the time.
They are one of the few species of sharks that form groups as most sharks are loners. The group may only have a few members or it can have up to 100. The larger sized groups are very rarely found though.