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OF PREDATORS & THEIR PREY To study the predatory
behavior of the Great White, scientists must travel to a
location where this overgrown fish is known to hunt it's
prey. Luckily, about 30 miles off the coast of San Francisco
are the Farallon Islands, home to a large elephant seal
population - making this area the local burger shop for
Great Whites's in the neighborhood and thus a hotspot for
research. The Great White Hunts Sea Lions.
From this data collected at the Farallon Islands, we now
know that most Great White attacks occur during the day
in late summer or early winter. Furthermore, the attacks
also took place at around the same time each day, most likely
due to the tide schedule.
Going back to the observational data, some interesting differences
in attack strategies were noted based on the species of
the shark's prey. For example, in the case seals, the great
white often attacks just beneath the surface by rising from
below. A large elongating blood stain at the surface indicates
that the shark carries the seal underwater for a distance
before removing a bite and releasing the carcass which then
floats to the surface. When this initial attack took place
near the head of the seal, an area rich with networks of
blood vessels, death by exsanguination (loss of blood) or
decapitation was the norm. On other occasions, the GW would
disable the seal by attacking from behind, biting the strong
hind flipper. Nature is pretty grisly stuff, huh?
Attacks are usually observed with the sea lion at the surface
of the water, the Great White strikes brutally, throwing
itself out of the water with the sea lion clamped in its
jaws. The sea lion, flounders at the surface until the shark
returns for the final kill and feeding.
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