176 Sharks: The Animal Answer Guide
identity, where the shark mistakes a person for a more usual prey item; and
(5) true feeding attacks.
Provoked attacks are the ones that occur when someone accidentally
or deliberately disturbs a shark. These are clearly not instances of sharks
trying to make a meal of someone but are more likely defensive reactions
by the sharks. Other provoked attacks are the result of careless handling.
Feeding and chumming for sharks also lead to provoked incidents, with an
excited shark biting the feeder.
The placoid scales of many sharks are sharp and can cause injury, and
people bumped by sharks are sometimes cut or scraped. Whether bumping
is provoked or unprovoked—or should even be considered an attack—can
be debated.
Unprovoked attacks by ray species are rare (unless you’re a clam). Pro-
voked attacks, however, are all too common and sometimes fatal. Electric
(torpedo) rays (Narcinidae, Torpedinidae) defend themselves by discharg-
ing powerful electric shocks. Fishers who handle a torpedo ray are invari-
ably shocked, and the discharge is strong enough to stun a person or worse.
We’ve seen grown men knocked to the deck of the boat from the discharge.
Some scuba drownings in southern California may have been caused by
encounters with Pacific Electric Rays (see “How do sharks detect electric
fields?” in chapter 2).
Stingray attacks are also invariably defensive. A wader steps on a ray,
and the ray responds by flexing its tail upward and forward, driving its
spine into the wader’s foot or lower leg. This spine has serrated sawtooth
edges coated with a protein-based venom and mucous that diffuses rap-
idly and breaks down the victim’s tissues. Stingray stings cause immediate,
intense pain, at least in people. The sawtooth edges create a large wound
when the ray or the person pulls back or removes the spine. Victims of
stingray wounds often describe it as the most painful thing they’ve ever ex-
perienced.
Fatal incidents involving stingrays are fortunately rare (no one keeps a
record of the number, unlike shark attacks). Sometimes divers mistake large
dasyatid stingrays (with spines) that are lying on the bottom for manta rays,
which don’t have spines—and don’t lie on the bottom. A diver may try to
take a ride, grabbing onto the front edges of the ray’s disk. The ray again
responds defensively, driving its tail and spine upward and forward, but this
time into the diver’s chest region. Fatalities from such incidents have oc-
curred. A documented death occurred in Sulawesi, Indonesia, when a diver
tried to hitch a ride on a large stingray. Speculation has it that “Crocodile
Hunter” Steve Irwin, who was killed by a large ray while diving on the
Great Barrier Reef in 2006, swam over or close to the ray, and the ray re-
sponded with a defensive tail thrust.
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