Comment: Marine parks increase risk of shark attacks

THE North Coast of NSW has experienced a sharp increase in shark sightings and attacks over the past two years. There have been 13 reported attacks, including three fatalities and hundreds of shark sightings on the section of coast between Forster and Byron Bay. Local swimmers and tourist numbers have plummeted and the impacts are being felt by local businesses. While debate rages amongst the public and government, and while scientists and experts scramble for solutions, there are some facts being ignored that are critical to the issue.

ENVIRONMENT NEWS: How many sharks are too many?

The benefits of marine parks have been well documented both here and abroad. The debate may rage on as to who should and shouldn’t be allowed to use certain areas but there is little doubt as to their effectiveness. While we frequently hear researchers and conservationists outlining the many and various benefits of marine protected areas, we seldom hear about the negatives.

A recent study commissioned by the Australian Marine Conservation Society found that marine protected areas have up to twice as many large fish species as non-marine protected areas, and up to five times more fish biomass. This is a somewhat crude and simplistic, yet arguably conclusive measure of the effectiveness of marine parks in relation to fish stocks, I’m sure most would agree. However, worryingly, the report goes on to reveal the bit that the conservationists and politicians seemingly don’t want us to hear, and that is that they also increase shark numbers by up to 14 times that of non-marine protected areas. The laws of the food chain are well known and documented, and, so it follows that if we increase the biomass of the lower end species then the top end predator numbers will also surely increase.

The NSW North Coast is home to some of NSW’ first marine parks. Are we now experiencing some of the unforeseen effects of marine parks in the form of increased human interaction with dangerous sharks? The Cape Byron MP, created in 2002, is at the centre of the recent series of attacks and sightings. It’s a large park, bigger than any in Victoria, and is nearing the age that the study shows has significant benefits for size and abundance of marine life. In other words, the Cape Byron MP is a mature marine park.

Other significant marine parks that have seen recent attacks include the Solitary Islands MP (created 1998) and Port Stephens MP (2005). Of the three recent shark attack fatalities in NSW, two were in marine parks and the other one less than 10km from a marine park. The sites are Campbell’s Beach at Coffs harbour, Shelly Beach at Ballina and Clarke’s Beach at Byron bay. This week’s attack on surfer Sam Morgan occurred only a few kilometres from cape Byron MP.

It’s also worth considering the situation on the French island of Réunion in the Indian Ocean, which has seen 18 attacks, including seven fatalities, since 2011. In 2013 the situation got so bad that the government banned all swimming and surfing and their tourism economy has since been devastated. In 2007 shark fishing was banned and a marine park established along the island’s coast. Many locals blame the marine park for the spate of attacks .

While it could be argued that the same rate of attacks have not occurred in NSW marine parks further south, such as the Batemans Bay MP, it should be noted that the three northern NSW parks in question represent a peak cross-over point of the three big man eaters. These include the tiger and bull sharks of the sub tropics and the great white shark from the temperate south. These three sharks are not found together in abundance further south, however they do occur off Sydney during the warm flush of the east Australian current each summer.

Recent results from the Reef Life Survey conducted by the Underwater Research Group show a significant increase in warm water fish in Sydney. If that’s accurate then we can expect to see increased activity in sub-tropical shark species such as tiger sharks. It should also be noted that activity levels of the other big man eaters, bulls and whites are also known to increase in warmer waters.

In Jan 2016 the Marine Estate Authority will be finalising a draft proposal for management of the Hawkesbury bio-region. The region includes most of Sydney, including the harbour, and the draft is expected to include marine sanctuary zones. Given what we now know about the success of marine parks – and the resulting increase of shark activity – is this something we really want for Sydney and surrounds? Sydney has a population of about five million people, many of which spend their recreation time in or on Sydney’s Harbour, waterways and 400 plus beaches.

The Baird government is scrambling to find ways to combat increasing shark numbers and attacks. But by implementing more marine parks for Sydney, they could be inadvertently making the problem worse by increasing shark numbers. Can Mike Baird assure the people of Sydney that the introduction of a marine park next to our largest city won’t lead to a repeat of what is happening in northern NSW right now?

As a staunch advocate of improving aquatic environments, including the shark population, I am in favour of marine parks. But not in major population areas like Sydney, and not when the evidence clearly links increased risk of shark attacks within close proximity of marine parks.

What's your reaction?

Related Posts

Load More Posts Loading...No More Posts.