![]() Males, identified by the presence of a pair of claspers near the pelvic fin, appear to become sexually mature when they reach a length of 8-9 m (26.2 to 29.5 ft), but the size of females at maturity is not known. ![]() Not a great deal is known about the reproductive process of whale sharks. Some biologists suggest that in instances when food is too large for the shark to swallow, the teeth may be used to process the food into a smaller, more manageable size. What the 300 rows of small teeth in each jaw do in the feeding process has not been definitely determined. These sharks have been observed hanging vertically in schools of baitfish while sucking the baitfish into their mouths. It may also feed actively by jutting out its jaws, gulping water into its mouth, closing the mouth and forcing the water through the filtering system and out the gill slits. This filter-feeding shark may feed passively by simply opening its mouth while it is swimming. While the whales use baleen plates as strainers and whale sharks use gill rakers, both open the mouth wide, engulf a large quantity of water and prey, then close the mouth and force the water through the mucus coated strainers that hold food preparatory to swallowing. The whale shark uses a feeding technique very similar to that of the large baleen whales. Along with the small forms of phytoplankton and zooplankton that are caught in its filtering system it will also eat sea jellies, small crustaceans, squid, and small fishes such as anchovies, sardines, mackerel, and similar species. The whale shark is a filter feeder and its modified gill rakers can remove food particles from sea water down to 1 mm (0.039 in) in diameter, but most of its food comes in larger dimensions. Although its mouth is huge, its gullet is small and limits the size of prey that it can swallow. It is interesting that the largest fish in the world utilizes small food items for its nutrition. As is the case with many shark species, females tend to be larger than males. Most whale sharks observed are 6 to 12 m (19.7 to 39.4 ft) in length. A larger specimen was reported from the Gulf of Siam and estimated at 18 m (59 ft), a questioned figure. A male specimen accidentally netted off of Bombay in 1983 was measured at 12.2 m (40 ft) and reportedly weighed 11 metric tons (24,250 lb). Reports about size and weight vary considerably, probably depending on the mode and circumstances of measurement. The dark shaded fins are irregularly marked with round, light colored dots. Vertical and horizontal lines of cream or white create a checkerboard appearance with round spots in the squares giving the impression of checkers on a board ready for play. The sides and back have a darker base color with shades of blue, gray, and brown. A very distinctive characteristic on each side of the upper body is the presence of three parallel, horizontally oriented ridges that start at about where the gill slits end and run the length of the body.Ĭoloration and color patterns vary from one shark to another. The caudal fin is semi-lunate (semi-crescent shaped) with the upper lobe much larger than the lower. The first dorsal fin is much larger than the second. The two dorsal fins are placed well back on the body. Five large, vertical gill slits are present just forward of and above the origin of the pectoral fin. The spiracles are behind the eyes at a similar distance. Its relatively small eyes (about the size of a golf ball) are located a short distance behind the angle of the jaw and at about the same level. It has a mouth full of small, sharp, almost scale-like teeth. Short barbels protrude from its nostrils. Unlike most sharks in which the mouth is on the undersurface of the head and set well back on the snout, the whale shark’s mouth is almost at the very front of its head. Its large mouth, which can be up to 1.5 m (4.9 ft) wide, extends the full width of the head. The largest of the sharks, it is well proportioned and beautifully streamlined even with its large, broad, flat head. It prefers warm tropical water, in a range of 21 to 25 o C (69.8 to 77 o F), but is more content when the warm water is interspersed with cooler, nutrient-rich upwellings that provide a good source of food. The whale shark is considered to be a pelagic open water fish, but it is frequently seen in shallower inshore waters associated with lagoons, bays, and coral reefs. World wide in tropical and warm temperate waters most commonly between latitudes 30 o N and 35 o S in oceanic and coastal waters with the exception of the Mediterranean Sea. This information is available so you can learn more about the largest fish in the world and its conservation needs. The awesome whale shark is not exhibited at the Aquarium. CLIMATE CHANGE: Not Applicable At the Aquarium
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