|Why do shark attacks happen?|
|Question Date: 2017-10-03|
According to NOAA (National Oceanic and
Atmospheric Administration) sharks do not
normally attack humans, and when it does occur the
reason is usually mistaken identity.
Sharks typically hunt sea lions, seals, and
similar-bodied prey. So humans in the water on
surf boards or kayaks can be mistaken as the same
body shape as those normal food sources.
Sharks can also investigate a potential food
source by testing a bite. Unfortunately, due to
the number of rows of teeth, a single shark bite
can result in death by blood loss.
Beyond mistaken identity, shark attacks are
generally considered to have four causes. The
primary cause being provoked attacks, when
humans in some way touch or disturb the shark.
This includes fisherman releasing sharks caught in
nets, divers taunting sharks, and other
The other three causes are unprovoked.
The first, common of mistaken identity when
investigating possible food, is an
unaggressive shark that grabs a person, releases,
and swims off. The others are aggressive,
as when a deep sea shark comes up and grabs a
diver unawares or when a shark comes up and
head butts the person before taking a bite.
As of 2016, the International Shark Attack File
through the Florida Museum of Natural History
revealed the five year world average for shark
attacks was 82 unprovoked attacks per year, with
only 5-15 actual deaths per year for the whole
world. Granted not all attacks will be reported,
but this record is considered relatively accurate.
ISAF predicts that you are 132 times more
likely to drown at the beach and 45 times more
likely to be killed by a rip current than to be
killed by a shark. That does not mean you
should ignore caution toward sharks while
swimming, especially in areas where sharks attacks
are known to have occurred, but that there are
specific behaviors you can do to reduce your
risks. I recommend investigating sharks further at
the ISAF website:
Many sharks eat large marine mammals, such as
seals and sea lions. Seals and sea lions have dark
colored coats that the shark recognizes as a prey
item. Many shark species swim in the middle of the
water column and attack prey from below. From
the shark’s point of view, humans in the ocean
that wear black wetsuits look very similar to a
seal or sea lion. This is what often leads to
To avoid shark attacks, a company in Australia
has made wetsuits that ‘break up’ the shark’s
vision so that humans no longer look like prey
items when the shark is looking up towards the
surface – check them out!
no more shark attacks
Sharks are meat-eating animals and humans are made
of meat. Also, sharks can confuse humans for their
more usual prey and attack them by mistake.
Sharks eat meat, and we are meat. So if a shark
saw one of us, it would think 'Food!'
Thanks for the great question.
Shark attacks are terrifying and dangerous, but
fortunately they are very rare. About 70
attacks happen every year, but given the number of
people in the ocean at any one point over a whole
year, the chances of encountering a shark and
getting attacked are very small.
There are nearly 500 species of shark, but only
three are responsible for attacks on humans,
the great white, tiger, and bull sharks.
Despite being uncommon, shark attacks have serious
There are two different types of reasons why
shark attacks happen: provoked or
unprovoked. The first occurs when a person
makes the first move towards the shark, for
instance if someone makes the first move to
touch a shark, or even accidentally bumps into one
in the water. In these cases, the shark may
attack because it is defending itself.
Other times, however, the shark starts the
attack. These unprovoked attacks can be
exploratory or predatory. The predatory shark
attack, where the shark wants to consume someone
for food, is the rarest type of attack,
because people are actually a very poor source of
food for sharks. More commonly, sharks bite
because they are exploring their environment, and
their mouth is the only way they can investigate
their world. So when sharks attack, it is most
often because they are curious about what’s in the
water, not because they want to eat people.
Unfortunately, a bite from a curious shark is
still immensely dangerous.
Thanks for the great question,
Click Here to return to the search form.
Copyright © 2017 The Regents of the University of California,
All Rights Reserved.