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education & training
Feature
Tiger shark
Sharks
In perspective
There are over 510 species of
shark worldwide and around
182 of these have been found
in Australian waters, but only a
handful are known to be dangerous
to humans.
The majority of fatal attacks in coastal waters
are attributed to just three species: bull sharks,
tiger sharks and great white sharks.
Bull shark
Carcharhinus leucas
(river whaler, freshwater whaler, Swan
River whaler)
Great white shark
Bull sharks have a short snout—wider than it is long. The underbelly
is usually off-white, with grey top surface, and the eyes are small.
Adults range from 2 to 3.5m in length and weigh up to 230kg. Their
teeth are triangular, saw-edged and very sharp.
In Australia, the bull shark can be found from the central NSW coast,
across the northern coast to Perth, WA. This area extends south to
Sydney during the warmer summer months. It is the only widely
distributed shark that penetrates far into fresh water for extended
periods where it sometimes breeds.
Bull sharks eat almost anything, including fish, other sharks and
rays, turtles, birds, molluscs, crustaceans and dolphins.
It is a dangerous shark due to its aggressive nature, powerful jaws,
broad diet, abundance, and its habitat preference for shallow, murky
inshore waters.
Tiger sharks
Galeocerdo cuvier
Tiger sharks have tiger-like, striped markings on a dark, grey-brown
back with an off-white underbelly. They can grow to around 6m but
are, on average, about 3m. Their teeth are heavily saw-edged,
cockscomb shaped, razor sharp, and are the same in both upper
and lower jaws.
In Australia, tiger sharks occur across northern Australia, and south
to southern NSW and Perth, WA.
It is one of the few sharks that is a true opportunistic scavenger,
taking a wide range of prey, including fish, turtles, crabs, clams,
mammals, sea birds, reptiles, other sharks and just about anything
else they can catch alive, as well as a variety of inanimate flotsam.
Their occurrence in shallow water, indiscriminate diet and large size
make them one of the most dangerous sharks.
Great white shark
Carcharodon carcharias
(white pointer, white shark, white death)
The underbelly of the great white shark is the only area that is actually
white, the top surface of the shark is grey, blue/grey or bronze.
The biggest recorded great white was 7m long and weighed
3,200kg. Their teeth are large, saw-edged and triangular.
In Australia, great white sharks have been recorded from central
Queensland, around the southern coast to North West Cape,
WA—however, they are more common in the south.
Young great whites (under about 3.5m) eat mainly a variety of fish,
rays and other sharks. Larger adults eat larger prey, including marine
mammals such as sea lions and seals, small-toothed whales and
otters. They also eat dead animals floating in the water.
Great whites are a protected species in many Australian states, and
also in several other countries.
Shark Attacks in Perspective
Compared to injuries and fatalities from other forms of waterrelated
activities, the number of shark attacks in Australia is
very low. In the last 50 years there have been 47 unprovoked
shark attack fatalities averaging just under one per year (0.94).
There is an element of risk in any activity, and the risk of a
person being injured or killed by a shark must be viewed
in perspective.
“Shark attacks are random events—no shark knows when a human
will enter the water so they can time an attack! There are many
instances where sharks are in the same area as a human and they
do not interact with them. Although random shark attacks can
cluster (occurring in a particular area or over a time period) and may
seem to many as an increasingly common event over time it is
shown that the number of incidents at a location or time of the year
vary from year to year and should be analysed over decades for
trends.” John West, Australian Shark Attack File.
Sources: NSW Department of Primary Industries; Australian Shark
Attack File (ASAF), Taronga Zoo, Sydney.
Bull shark
“Shark attacks are
random events …
There are many
instances where
sharks are in the
same area as a
human and they
do not interact
with them.”
Unprovoked Cases (last 100 years only) as of December 2015
State # Cases Fatal Injured Uninjured Last Unprovoked
fatality
NSW 212 49 111 52 Ballina 2015
QLD 160 56 87 17 Palm Island 2011
WA 79 14 53 12 Gracetown 2013
SA 42 13 22 7 Glenelg 2005
VIC 32 3 19 10 Mornington Peninsula 1987
TAS 9 1 5 3 Maria Island 2015
NT 8 1 6 1 Cobourg Peninsula 1934
Note: An ‘unprovoked’ encounter between a human and a shark is defined as an incident where a shark is in its natural habitat
and has made a determined attempt to bite a human where that person is not engaged in provocative activities. Incidents classified
as ‘provoked’ are not included in these statistics.
Source: Australian Shark Attack File, Taronga Zoo, Sydney
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Australian Lifeguard Magazine 15