Shark detection device under testing.
From SMH by Peter Hannam
Shark nets and aerial searches to protect the nation’s beachgoers
may become costly relics of the past if digital technology able to
detect the potentially menacing creatures succeeds.
Dubbed the
“Clever Buoy”, the floats use sonar devices to
search for objects of greater than two metres in length approaching
within about 60 metres.
If confirmed as a shark, the device will send
an alert via satellite to beach-based lifeguards who would then
evacuate swimmers.
Shark Mitigation Services (SMS), which has tested the
technology at the Sydney Aquarium and at the remote Abrolhos Islands
off the WA coast, hopes to release commercial versions by the middle of
next year.
Introducing Clever buoy
“It’s like face-recognition software,” said Hamish Jolly, a
director of the company.
“We can teach the software to look for the
unique characteristics that we see in large sharks swimming.”
If the WA experience is any guide, governments could do with more accurate methods to identify and respond to shark threats.
Bowing to public fears after a series of shark deaths off WA
beaches, the WA government began culling sharks in January and is
seeking a three-year extension from federal environment minister Greg
Hunt.
The cull, though, failed to catch a single great white shark
– its main target.
Many of the 172 sharks caught were tiger sharks,
which have not been linked to recent human fatalities.
Clever buoy - Testing the sonar
An interest in shark conservation was one reason why
telecoms provider Optus teamed with Mr Jolly’s company to provide
satellite expertise for the buoys.
“We want to provide the environment that’s safe for
beachgoers but also provides the opportunity to protect sharks
long-term as well,” Nathan Rosenberg, head of Brand and Communications
for Optus, said.
Shaun Collin, head of the University of WA's Oceans
Institute - which has worked with SMS on other research - said the
presence of a shark "certainly does not mean an attack is imminent".
The way forward is to quickly identify any potential risk,
convey that to the public while also deploying a deterrent to ward them
off, Professor Collin said.
World-leading shark scientists at the University of Western Australia
now understand exactly how sharks see.
In collaboration with the
university, SAMS has also translated the scientific data into a range of
patented shark deterrent and repellent wetsuits, along with other
products now available online.
Test footage was captured by National
Geographic.
Worldwide options
The use of satellites rather than mobile phone networks
would allow the buoys to be anchored off remote beaches in Australia
and elsewhere.
“We want to be able to deploy this anywhere in the world,”
Mr Jolly said, adding that Hawaii and Reunion Island in the Indian
Ocean were among possible markets.
The final cost of the buoys, developed using Google platforms, remains unclear.
Although sharks remain a tiny threat for most ocean swimmers
- the number of unprovoked shark encounters a year has doubled since
the 1960s to about 80 worldwide – local authorities are going to invest
to reduce the risk, he said.
“At the moment, the alternatives are aerial spotting,
netting and visual patrols from lifeguards,” Mr Jolly said.
“(The buoy)
is going to have to fit into that cost array in order to be
competitive.”
A rise in deaths is understood to be largely down to more
people entering shark space.
The recovery of whale numbers, such as
humpbacks, is also likely to raise shark bite risk, according to a
study out earlier this year by Peter Sprivulis, a professor of
emergency medicine at the University of WA.
NSW has recorded 47 fatalities from sharks in the past 100
years, including the death of Christine Armstrong off Tathra in April,
according to Taronga Zoo’s Shark Attack File.
For
Victoria, the last death from sharks was in 1987 on the Mornington
Peninsula, with four fatalities in the past century.
WA’s shark deaths
total 19 during that time.
Tests now underway are to extend the operating life of the
systems – batteries now need to be replaced each day – and to determine
whether the most effective use involves lines of buoys creating a
virtual perimeter fence.
Links :
- WP : After shark attacks kill surfers in Australia, the government is killing sharks
