Characteristics of a Whale Shark

Habitat

• The whale shark is quite cosmopolitan in its choice of habitat, living in both the open oceans and near the coast, even in relatively shallow waters. It inhabits warm waters, occurring in all temperate and tropical seas with the exception of the Caribbean. The species appears to regularly migrate vast distances. Tagging has shown that individuals travel thousands of miles, including a migration of more than 8,000 miles over three years. These journeys are possibly to find the places richest in food, which vary according to the season and other factors, or breeding sites.

Physical Characteristics

• Whale sharks are the largest member of an order of predominantly very small sharks, the carpet sharks. The great size is the most obvious characteristic, with confirmed measurements of whale sharks of 40 feet. Some individuals may grow significantly larger than that. Other features are a dappled body and a mouth that can open very wide to capture food.

Diet

• Like the baleen whales, a large proportion of the whale shark's diet consists of near microscopic plankton, which it filters out of the water. Whale sharks also eat somewhat larger organisms, including small fish and squid. Although the shark has plenty of teeth, they are all very small teeth. The whale shark doesn't, and can't, prey on large fish or mammals in the manner of species such as the great white shark. This diet means the species is harmless to humans, who are far too big to be potential meals. The most harm a whale shark could ever do to a swimmer would be accidentally knocking him with its tail.

Life Cycle

• In 1996 it was established that this species is ovoviparous -- the mothers give birth to live young rather than lay eggs, but there is no placenta. The shark recorded had 300 embryos, so it appears the mothers have a number of pups at a time, although the average litter size is unknown. Given their size, whale sharks are probably slow to grow and to mature. Estimated maximum age is about 60 years or more. Adult whale sharks have few natural predators. Other large sharks or orcas may target the adults, but are more likely to hunt juveniles.