SharkTrust Article: Kill or be killed - Are great white numbers on the increase?

IT'S feeding time in the waters around Port Lincoln. Great white sharks detour off the shark "highway", following tuna pens and boats as they come into shore, drawn by the blood trailing in the water.

Along the way they find a sheltered haven around the Neptune islands, near the entry to Spencer Gulf. There they prey on dolphins and calving seals. Often they're met by scientists or caged divers who release minced fish to attract their attention. Further into the gulf there are millions of tuna, locked in deep-water pens, being fattened for restaurants in Japan.

While they hunt for seals in deeper waters at night, the sharks trawl in shallow water by day, searching for snapper or stingray. The sharks might also come across a swimmer, an abalone diver or a surfer catching a wave. Their instincts tell them human equals food.

"There are schools of salmon that swim along that coast: standard shark food," says Port Lincoln Mayor Peter Davis. "A bloke in a wetsuit looks just like a seal."

So it was for Jake Heron, a 40-year-old Port Lincoln cray fisherman who was mauled by a great white on Sunday while on a Father's Day surfing trip. He survived but needed more than 60 stitches to his thigh, calf and arm.

Only two weeks ago, diver Jarrod Stehbens was killed by a great white 5km out from Adelaide's popular Glenelg Beach.

Fishermen who see great whites daily and are familiar with their movements predict there will be more attacks across Australia's southern waters at popular swimming spots in Victoria and Western Australia. "September is a prime month for feeding sharks," says one Port Lincoln tuna farm diver and surfer. "There will be another attack near Torquay or Cottesloe before the end of the month."

Research shows great whites will be travelling along these stretches during spring. More than 250 white sharks tagged and tracked by the CSIRO cover thousands of kilometres, travelling at a steady speed of 3km per hour. They move up along the east coast during autumn and winter as far north as central Queensland, returning south in the spring. Along Western Australia they move up the coast as far as North West Cape during spring and return south during the summer. It is in the South Australian waters, around Port Lincoln and along the Great Australian Bight, that they congregate from September.

In and around Port Lincoln few people doubt shark numbers have dramatically increased in the past eight years. "There's no way I'd go out on that bay now," says Heron's mate Craig Matena, also a keen surfer. "All Port Lincoln people know, all of the west coast people know, the shark numbers are just huge out there at the moment, and they never used to be."

Blame is apportioned to the $320 million tuna industry, founded 10 years ago. Others point the finger at the ban on hunting great whites, introduced federally in 1997 to protect a species that is considered endangered.

Gavin Roberts, a marine engineer and former professional diver in Queensland, says attacks will continue while the shark remains protected. "I think it's going to keep happening around the coastal area as long as we keep on protecting the great white shark," Roberts says. "It appears the population of great whites is increasing."

Roberts, who gave up diving 10 years ago after a close encounter with a shark, says they will continue to come near suburban beaches as they grow more accustomed to boats and humans. "It's like a dog. If you can train it to go where the food source is, they will continue to go there." Roberts says sharks also have less food available to them than 200 years ago, as commercial fishing has depleted stocks of some species. "We haven't got the seal colonies and the snapper there used to be."

The tuna industry has also noted an increase in shark numbers along the coast but denies it's at fault, instead blaming protection laws. Stehr Group farm manager Robbie Staunton, who has been involved in the industry since it opened at Port Lincoln in the mid-'90s, says shark numbers have slowly increased. "In the first three years we didn't see a single shark," Staunton says. "Two years after they started being protected, I started to see them increase. Farms are out there, there are more boats out there, we see more [sharks]."

When boats leave the harbour after harvesting is over, Staunton says shark sightings drop. "They [sharks] go away and come back again the next year with a friend."

According to federal government research, the number of great white sharks around Australia is not increasing. The CSIRO says while the catch and sighting data is ambiguous, figures suggest "a decline in abundance".

Internationally known diver and marine conservationist Ben Cropp says although there has been a steady rise in the number of fatal attacks off Australian beaches in recent years, the shark population is dwindling. Cropp says the recent spate of attacks is more likely due to more people being in the water. "The coastal boom of the past five years has been enormous," he says. "You have people moving to the coast, spending a lot more time out on the water than they did 20 years ago. The risk of being attacked is like 10 million to one, but if you have twice as many people in the water, those odds are obviously halved."

There have been three attacks -- two of them fatal -- in South Australia since December last year and eight fatalities since 1990. Authorities are allowed to shoot any shark they believe has taken or threatens lives. This summer swimmer safety is reliant on planes patrolling the coastline and a new helicopter watches metropolitan beaches up to a distance of 600m offshore.

In Western Australia, where there have been six fatal shark attacks since 1990, aerial shark patrols will cover beaches from Two Rocks to Avalon Estate, south of Mandurah. Western Australia also has a shark incident emergency response plan, where fisheries department officers use two oceangoing boats while police search for the victim.

With higher populations, warmer weather and longer beach strips for swimmers, NSW and Queensland have recorded most of the shark attacks in Australia since 1900. After five fatal attacks off Sydney beaches between 1934 and 1937, NSW established a shark menace advisory committee in 1937 and 51 surfing and swimming locations are protected by mesh nets. There has only been one fatal attack at a protected beach since the program began.

A shark control program was introduced in Queensland in 1962 in response to a public outcry over fatal attacks on the Sunshine Coast and at Mackay. Queensland now uses a combination of nets and baited hooks on drums. There have been no fatal shark attacks since the control program was introduced on the protected beaches, which stretch from Cairns to the Gold Coast.

A study of shark mitigation by the National Marine Science Centre in Coffs Harbour shows the programs at NSW and Queensland beaches have been "very successful" in reducing the number of shark attacks.

Between December 1900 and March 2005, there have been 120 shark attacks resulting in injury in NSW and 140 in Queensland.

Back in Port Lincoln, the debate is raging about what to do.

The community is divided on a cull because the great whites are also a drawcard for international tourists. Even the town's visitor information centre sells great white T-shirts.

Survivor Heron is worried a shark could attack children swimming in the bay and says the answer is "controlled culling". His daughter Bella, 5, watched from a rocky outcrop as the shark attacked her father. His friend's daughter, Georgia, 10, was waiting on the rocks for her first surf. Either girl could have been a victim.

"They need to do something in Port Lincoln, for the kids' sake. Someone's going to be taken in the bay," Heron says. "The numbers have gone up and there are too many of them. It's time they started controlling the numbers."

Source: www.sharktrust.org