Great White Shark Behaviour Basics:
The Great White Shark engages in a number of behavioral and social activities, ranging from courtship to complex social behavior. White sharks are generally very curious animals, they display intelligence and they even socialize if the situation demands it.
Below are a few types of behaviours you may see around the boat:
Sharks do not have arms, legs, hands or feet. What they do have is a mouth, with sharp teeth. A mouth that is capable of immense biting force (1800pounds per square inch), but is also capable of a gentle, inquisitive bite, a way of first testing the object which has caught their curiosity. Much like human babies do when they place objects into their mouths to examine it.
Observations are limited as far as white sharks gaping at each other, but it does occur. This behavior is possibly a method whereby individuals gauge the size of their opponents fighting tools.
Spyhopping is a behaviour also associated with whales. Great Whites have developed this behaviour to investigate objects above the surface. Their favourite prey, the Cape Fur Seal, is found on rocky out crops and spyhopping enables the shark to see where they are. It is an effective hunting tool.
You may witness this behaviour around the boat too, as their natural curiosity sometimes make the sharks spyhop around the boat to get a better view of us and the boat.
There are some spectacular and breathtaking photos of Great Whites breaching. They are ambush predators and therefore a hunting strategy such as a breech, is an efficient way to ensure a kill. Seals are very agile and the ambush tactic is the most effective way to ensure a kill. The Great White only has one opportunity to make the kill, for if the first attack is unsuccessful the seal can generally out manoeuvre the shark and get away.
Even though breaching is generally associated with predatory bouts when white sharks hunt seals, they have been observed breaching on other occasions too. The reasons for which may include communication, displacement behaviour and removal of parasites or simply just jumping for joy.
This behaviour is typically observed between white sharks when they are in an active group of 2 or more sharks. It has also been observed directed at divers in a cage. It will occur when sharks are swimming parallel towards each other or in the same direction. Either shark, or both, will twist its head towards the other and then continue on their original course.
INSHORE/OFFSHORE SEASONAL MIGRATION:
White sharks use the South African coastline differently throughout the year. They spend the summer (Aug-Mar) very close inshore and during the winter (Mar-Aug) they congregate around seal colonies such as those in False Bay, Mossel Bay and Dyer Island.
The exact reasons behind this transition between inshore and offshore migratory behavior is not entirely clear. There are 2 possible reasons for these migrations:
1) A change in prey: their diet changes from seal pups in the winter at the islands to game fish runs and smaller shark species that use the inshore bays during the summer.
2) White sharks possibly give birth and mate in the bay during the summer. They can be seen patrolling the breakers where the water is particularly rich in oxygen. When they stop swimming to mate, they can then revive quicker with the increased oxygen levels.
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