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Great White Shark: Food & Feeding

The white shark is a macropredator, and is active during the daytime. Its most important prey are marine mammals (including, seals, sea lions, elephant seals, dolphins) and fish (including other sharks and rays).

Marine birds and sea otters are commonly found having suffered injuries from encounters with white sharks, but are rarely eaten by them. Great white sharks assess the energy value of prey in the first bite. If the prey doesn't have enough energy value to justify the energy needed for a full-scale attack, the shark releases it. If however the great white perceives the prey to be energy rich, it will give a devastating, powerful bite and wait for the prey to bleed to death. White sharks swallow creatures without chewing them, and can swallow objects half their size.

Prey detection and identification by white sharks has been studied by the use of experimental baits and objects. The results of these experiments reveal that when white sharks have a choice between a square target and a seal-shaped target, they select the seal shape, as it is more common in their natural environment. When only a single bait was presented, it was regularly investigated. Some scientists believe diver and surfer silhouettes, when viewed from below, resemble those of pinnipeds and that this misidentification by the shark is the cause of most white shark attacks on humans. However, the fact that white sharks attack objects of a variety of shapes, colours and sizes, none of which resemble those of marine mammals, refutes this well-known hypothesis. Researchers suggest that white sharks often strike unfamiliar objects to determine their potential as food. Grasping an unfamiliar object would be the shark's only reliable method of determining whether it is suitable as prey. Great whites prefer energy rich prey, such as marine mammals, rather than less fatty, low energy prey.

White sharks usually swim just below the surface until it is approximately 1 m from its prey and then attacks by turning the head upward and rising out of the water. The white shark also attacks prey with a surface-charge, which is a quick, powerful rush with the body partially above the surface. Occasionally great whites swim with their ventral side up and perform an inverted approach. Their intelligence means they are able to adapt their hunting strategy depending on the prey. In the shallow waters of South Africa they often use stealthy ambush techniques to capture seals. These result in the spectacular breaching scenes when sharks chasing seals in False Bay and Gansbaai take to the air like missiles. White sharks sometimes scavenge from fishermen's nets and long lines. This tendency often results in accidental injury on hooks or in nets.


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