White Shark Breaching
Among the most spectacular of White Shark behaviors
observed at Seal Island is the breach, in which a several hundred-
to several thousand-kilogram animal explodes from the sea in an awesome
display of power and acrobatic prowess.
Not only are these events astonishing to watch, but they also reveal
clues about how White Sharks normally attack their prey. Unfortunately,
one can virtually never determine where a White Shark is going to
breach before it actually does, making this phenomenon difficult to
study or capture on film.
To facilitate observation, photography, and filming of White Shark
breaches in False Bay, Chris Fallows and Rob Lawrence of African Shark
Eco-Charters developed a technique of slowly towing a seal-shaped
decoy behind a boat. Sometimes, a White Shark will hit the decoy
within very few minutes of beginning a tow. At other times,
White Sharks seem completely uninterested in the decoy.
Interestingly, shape discrimination in White Sharks seems to be partially
dependent upon its state or motion or rest. A seal-shaped decoy
that is floating more-or-less stationary on the surface must be shaped
reasonably accurately to elicit investigatory behavior; in contrast,
a towed decoy need not be shaped all that accurately to elicit a spectacular
response.
Below are a few stills captured from video shot by
Rick Allen of Nautilus Productions and a short video-clip from a rare
and particularly spectacular double breach. On a separate page,
there are close ups of the damage done to the decoy (carved from a
body surfing 'boogie board'), including a preliminary analysis of
the size and technique of the attacking White Shark.