(ABC News)
Shark Attack: Cookiecutter Shark Makes First Documented Attack on Human in Hawaii
A small shark that's as nasty as it is fearless, attacking
everything from Navy submarines to killer whales, has
been blamed for its first clearly documented attack on
a live human being.
A so-called cookiecutter shark, which was probably a
little more than a foot long, took a chunk out of the
leg of a distance swimmer who was trying to make a
nighttime swim from the island of Hawaii to Maui.
The attack occurred 90 minutes after sunset March
16, 2009, but has just recently been documented by
scientists in Hawaii and Florida.
Despite their reputation, sharks historically have not
posed a widespread danger to people. Only two other
cases involving attacks on humans by cookiecutter
sharks have been widely accepted by experts, but
both those attacks were on human cadavers, one a
drowning victim and the other a suicide.
While this is the best evidence yet for attacks on live
humans, there are several other cases that are highly
suspicious.
So, are we in for another Jaws? Maybe not, because
the cookiecutter shark, so named because it gouges
horrific pockets of flesh from its prey, feeds at night
in deep tropical waters where it is not likely to
encounter humans.
But this case is so spooky that the director of the
International Shark Attack File at the Florida Museum
of Natural History thinks people ought to at least be
aware the nature of this predator.
"It's not as scary as 'Jaws,' but it's very different from
any other kind of attack we have [in the file] because
of the size of the shark and the modus operandi,"
George Burgess, director of the file, said in releasing
the study.
It is to be published in an upcoming edition of the
journal Pacific Science.
The shark is a master of the hit, rip and run
technique. It likes deep waters and has been
documented swimming as deep as 2.3 miles. But
when the sun goes down, it moves up through the
water column, searching for prey. Anything will do,
as apparently it fears no one.
It likes a moonlit night, and it usually approaches its
target from below, literally sucking up to the prey by
attaching itself with suction from its fleshy lips. It
sinks its hook-like upper teeth and then its
"proportionally massive lower teeth" into its victim.
Then it twists sharply, gouging out a chunk of meat
much like a cookie cutter. Or as some scientists
believe, like one of those tools used to carve out
melon balls.
While the shark doesn't get any bigger than 20 to 22
inches, size doesn't matter in its kingdom. It has been k
nown to attack northern elephant seals, whale
sharks, leopard seals, killer whales and, yes, even
submarines, according to the study.
The Navy had to replace rubber seals and coatings on
many of its subs after cookiecutters chomped holes in
them.
And now, perhaps, it has developed a taste for
humans.
No one knows that better than Mike Spalding of Maui.
In March of 2009, Spalding, then 61, waded into the
water off Upolu Point to try to swim across Alenuihaha
Channel to Maui.
He was accompanied by a 30-foot escort vessel, the
Radon, and a kayak.
Shortly before 10 p.m., it had become so dark that the
Radon skipper turned on his night lights. A little later
he asked the person in the kayak to turn on lights as
well. The bright lights probably attracted squid
toward the surface, a common prey for the shark.
Cookiecutter Sharks Travel in
Packs
"About 10 minutes after the kayak's bow light was
turned on, the victim was bumped by a squid," the
study says. "Over the next 20 minutes he was bumped
by squid two or three more times in the shoulder and
side areas at irregular intervals."
At 10:03, Spalding felt a very sharp pain on his lower
chest. "The sensation was instantaneous and
localized, like a pin prick, and felt like a bite from a
small mouth. The victim yelped and swam over to the
kayak."
Less than 15 seconds later, while he was trying to
crawl aboard the kayak, the shark hit his left calf. It
took a chunk of flesh that was later estimated to be
four inches wide and at least an inch and a half deep.
Spalding was rushed to Maui Memorial Hospital,
where his doctor, Peter Galpin, a co-author of the
study, began treatment. A skin graft was "harvested"
from Spalding's left thigh and used to close the open
wound.
It took nine months for it to heal.
While Spalding is the best documented victim of a
cookiecutter shark attack, the incident has fueled
concerns expressed during the years by other
scientists, because while this shark is -- fortunately
-- a little fish, it travels in schools and is suspected
of at least two mob attacks.
In the 1980s, an underwater photographer was
"attacked by a swarm of small sharks" and his wounds
resembled the scars that have been found in many
marine animals that were clearly the work of
cookiecutters.
And a 1955 report told of a shipwrecked crew in the
mid-Atlantic, just north of the equator, who "were
greatly bothered by the attacks of an extremely
ferocious small fish less than a foot long and blunt
nosed. These small fish swam in schools and were
very persistent. The bites were clean cut and upwards
of an inch or more deep."
But these are rare cases, and usually happen at night
far from shore in tropical waters, where humans
rarely swim. On the other hand, the study notes that
the shark's "hit and run feeding behavior" is a little
troubling.
The cookiecutter doesn't spend a lot of time analyzing
the situation and it has no fear of larger creatures, so
a human swimmer might just be a "novel potential
prey item" for the shark.
The scientists suggest that special care should be
taken when swimming at night in tropical waters "near
man-made illumination, during periods of bright
moonlight, or in the presence of bioluminescent
organisms."
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