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 The
white shark occurs throughout temperate oceans and is also occasionally
found in the tropics (Fergusson, 1996). Although it is most commonly found
in coastal and shelf waters, white sharks have also been found to dwell
offshore, swimming at depths of up 700m to and migrating great distances of
up to 3800km. It is most commonly encountered around coastal waters
inhabited by pinnipeds and around offshore reefs. They seem to prefer
waters with a temperature of 15-22°C although the range in which it has been
recorded varies from 4-27°C. Records of white sharks show them to inhabit
Australia, New Zealand, South Africa, the Mediterranean and Red Seas,
northern coasts of France and Spain, Portugal, the North-West coast of
Africa, Japan, Chile and both coasts of temperate North America, most
notably off the coast of California.
There
appears to be two types of long-term shark movements, the nomadic spatial
behaviour and the site fidelity, or repetitive occurrence, spatial behaviour.
The numbers of nomadic and resident sharks in an area on any given day can
fluctuate as the sharks are forever moving and seldom remain close to
observers. In Australia, some work has been conducted to determine the
movements of white sharks off the South Australian coastline. One shark was
found to remain at the Neptune Islands until early September before moving
into the shallower waters of the Spencer Gulf and then traveling west to the
Great Australian Bight in October (Bruce, 1992). Archival tags used in 1999
showed that white sharks showed frequent cycling between the bottom and the
surface both at night and during the day. Although the maximum depth
attained was 94m during the period of tracking, the shark was seen to mostly
remain at depths of less than 20m, with 10% of the time spent at the
surface. This study also showed that the shark, a female, remained in the
South Australian Gulfs until late October before rapidly moving to the Great
Australian Bight within a ten day period.
 Satellite tagging
has also been conducted at the islands off California. The results of their
study confirmed that white shark appear in autumn just as the young elephant
seals arrive to rest prior to mating. Whilst in the area, sharks generally
remained at depths shallower than 30 meters, swimming in waters ranging from
10-14ºC. In 2002, scientists implanted six sharks from the Farallones with
satellite tags. Whilst the sharks were in coastal waters, it was found that
they spent the majority of their time swimming between the surface and 30m
depth with the deepest depth obtained being 75m. This resulted in a
temperature range of 10-14ºC. The scientists discovered that this species is
not nearly as coastal as was previously thought and actually appears to have
a pelagic phase to its life cycle. In the study, one male migrated from the
tag site 3,800 kilometers to the Hawaiian island of Kahoolawe, traveling at
an average of 71 kilometers a day and then remaining in Hawaii for winter
and spring. Two females and a male were tracked migrating to the subtropical
eastern Pacific, spending several months in offshore pelagic waters, and
inhabiting depths of up to 660m, although more generally 300-500m. As the
shark moved offshore, the temperatures experienced ranged from 26ºC in
surface waters to 4.8ºC at depth.
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