SHARK ATTACKS ON A WHALE SHARK (RHINCODON TYPUS) AT NINGALOO REEF, WESTERN AUSTRALIA

摘要

The planktivorous whale shark, reputed to attain lengths of up to 18 m, is the world's largest fish (Coleman, 1997). The immense size of whale sharks may offer a refuge from predation (Peters, 1983) by large sharks and killer whales, Orcinus orca (Linnaeus, 1758), similar to other marine megafauna such as cetaceans (Pitman et al, 2001). At present, there is only one published observation that suggests that whale sharks might be susceptible to any top order predator other than man (Fertle et al., 1996). However, very little is known of the biology and ecology of these animals, and the lack of predation records on whale sharks may simply reflect the fact that they usually inhabit tropical oceanic waters, far from coastal regions where predation is likely to be observed.