Australian_Geographic_-_December_2015_AU_

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November–December 2015 35

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MALL WAVES MAKE fin-like
peaks near South Australia’s
rocky Neptune Islands, a popular
hangout for great white sharks.
Standing on the deck of his boat Shark
Warrior, Matt Waller – fourth-genera-
tion fisherman turned tour operator


  • is trying to lure the apex predators
    towards us using bobbing waterproof
    speakers. Flicking through songs on
    his iPod, he stops on an old faithful by
    grizzled Aussie rock legends AC/DC.
    Since the 1960s, the waters of the
    Neptune Islands Group (Ron and
    Valerie Taylor) Marine Park, 60km
    south-east of Port Lincoln in SA, have
    hosted the Australian shark-diving
    industry – and for 13 years have been
    the only place in the country where
    you can cage-dive with sharks. Despite
    fears about the increasing frequency of
    shark attacks, and controversies
    around responses to them, great whites
    are listed as vulnerable and receive
    some degree of protection. Tour
    operators and researchers working out
    of Port Lincoln believe that the more
    safe and controlled encounters people
    have with the fearsome fish, the more
    likely they are to join the call for even
    greater levels of protection.
    Historically, sharks have been lured
    towards tour boats by a trail of chum
    (or berley), a smelly mix of tuna oil
    and minced fish, which they can
    detect from several kilometres away.
    However, in recent times, recorded
    music has been found to exercise a


similar attraction. “The first success
we had,” Matt says, as he helps tourists
into a cage at the back of the boat,
“was with Back in Black and You Shook Me
All Night Long”. There was also a 4.5m
female that would arrive every time
the marimba-heavy Sax and Violins by
Talking Heads was played. In truth,
sharks have eclectic tastes, and are
attracted by many types of music,”
adds Matt, who runs Adventure Bay
Charters. But he has noticed they are
more likely to respond to the lower
frequency beats of hard rock.
According to Dr Peter Klimley,
a shark-tracking specialist at the
University of California, that’s not
as ridiculous as it seems; he’s used
lab-produced sounds to locate sharks
for tagging and tracking. Sharks ‘hear’
sounds from objects much further
away than those they can see, using
follicles in their skin as well as their
ears to detect vibrations. As far back
as the 1960s, American scientists were
discovering that various species were

attracted to irregular, pulsed sounds of
frequencies at less than 375Hz.
Their so-called yummy sound
theory suggests that this mimics the
sounds of struggling, injured fish, and
acts like a dinner bell. It’s a technique
that Adventure Bay Charters have had
to adopt since a 2011 CSIRO study
recommended a reduction in chum-
ming. Scientists had reported that a
boom in cage-diving at the Neptune
Islands had seen the population grow
and sharks hang around for longer,
signalling a change in their natural
behaviour. Matt’s business, one of the
youngest, lost out on a chumming
licence soon after. Having heard that
operators were successfully using
music off the Mexican island of
Guadalupe, he gave it a go, and now
takes out 2500 passengers annually,
using tunes as bait to draw in the
sharks. Music also seems less disrup-
tive to the sharks, Matt says. “They’re
more curious and a lot less aggressive.”
While I’m out with Matt, death
metal act Darkest Hour is the musical
drawcard. A 5m great white rises
from below and heads straight to
the speaker, nuzzling it before sinking
again, sending shivers of excitement
through everyone in the cage.
NATSUMI PENBERTHY

Sharks


rock out


Shark bait. Underwater speakers playing a
variety of tunes (left) are used to entice great
white sharks (above) closer to divers in the
waters off SA’s Neptune Islands, where the
live shark footage was filmed for Jaws in 1974.

RALPH ALPHONSO /


Carcharodon carcharias


Chum has long been used to
entice sharks, but it seems they
have slightly more eclectic
tastes when it comes to music.

SOUTH
AUSTRALIA

Neptune ADELAIDE
Islands

WILDLIFE ENCOUNTER

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