Sunday, 16 October 2016

Not impressed by the arguments made for shark netting the NSW Far North Coast

The following article was one of the more balanced media reports on shark attacks on the NSW North Coast since the fatality at Ballina in 2015.

A fatality which brought shark attack deaths in the region to seven in thirty-four years – that is, an average of one fatality every 4.85 years.

The Sydney Morning Herald, 15 October 2016:

The Baird government's decision to drop its opposition to shark nets for the state's northern beaches ignored recommendations of one of its own departments and the scientific consensus, experts say.

Another shark bite last week – the sixth since the start of 2015 for the Ballina-Byron area alone – was the last straw for Premier Mike Baird. On Wednesday, he explained his backflip, saying it was time to "prioritise human life over everything".

Only one fatality has been recorded in the state's 51 netted beaches since their introduction in Sydney in 1937, back in 1951. There have, though, been 33 so-called unprovoked attacks some serious ones.

"We need some sort of protection," said Richard Beckers, owner of Ballina Surf shop and a supporter of the nets.

Mr Beckers said he had cancelled $100,000 in orders after two incidents in as many weeks. Sales of body and surf boards have dived about 90 per cent as surfers head to beaches considered safer elsewhere….

Until last week, Mr Baird – himself a keen surfer – had resisted calls for the nets. Instead, he heeded advice from scientists who argue there is little evidence nets alone make beaches safer while killing thousands of marine creatures over the years.

The policy reversal "is a political decision – it's not based on data," said Culum Brown, an associate professor at Macquarie University. "The costs are well known and there's little to nothing in terms of benefits."

Existing nets are typically 150 metres long and about six metres deep, allowing plenty of space for sharks to get around, over or under them.

A parliamentary inquiry earlier this year recommended the Department of Primary Industries "move toward replacement of current shark meshing with more ecologically sustainable technologies".

Colin Simpfendorfer, director of the Centre for Sustainable Tropical Fisheries and Aquaculture at James Cook University, said great white sharks have been protected for two decades in a bid to reverse their population's steep decline.

"The whole point [of nets] is that they catch sharks," Professor Simpfendorfer said. "You are looking to reduce the abundance of sharks where people want to swim."

The 189 sea creatures caught in the existing nets in 2014-15 included 44 target sharks – whites, tigers and bulls – as well as harmless shark species, dolphins and turtles. Of these, 116 died before they could be released, government data shows.

Over the past century, the national annual deaths from sharks is 1.3 people on average, rising to two people during the past five years, according to Taronga Zoo's shark file. Australians make an estimated 100 million visits to the beach a year.

By contrast, five people died from dogs in 2013, with 44 killed by falling out of bed, the Australian Bureau of Statistics said.

"You're more likely to get killed by bees or by horses than by sharks," Professor Brown said.

Of course the NSW Coalition Government, and particularly Premier Mike Baird furiously chasing electoral popularity in the face of falling poll numbers, is not inclined to step back from the recent back flip on shark netting.

Readers can make up their own minds about whether trying to lay shark netting on the NSW Far North Coast in the face of an increasingly warm and fast Australian Eastern Current and frequently gale-driven coastal seas is going to work.

The Baird Government's $16 million attempt earlier this year to install shark netting at Lighthouse Beach, Ballina and Seven Mile Beach, Lennox Head failed miserably due to predictable rough conditions, large swells and sand movement along the coast.

Below are excerpts from Changing patterns of shark attacks in Australian waters (2011) by John G. West Coordinator, Australian Shark Attack File, Taronga Conservation Society Australia.

ABSTRACT. Although infrequent, shark attacks attract a high level of public and media interest, and often have serious consequences for those attacked.
Data from the Australian Shark Attack File were examined to determine trends in unprovoked shark attacks since 1900, particularly over the past two decades.
The way people use the ocean has changed over time. The rise in Australian shark attacks, from an average of 6.5 incidents per year in 1990–2000, to 15 incidents per year over the past decade, coincides with an increasing human population, more people visiting beaches, a rise in the popularity of water-based fitness and recreational activities and people accessing previously isolated coastal areas.
There is no evidence of increasing shark numbers that would influence the rise of attacks in Australian waters. The risk of a fatality from shark attack in Australia remains low, with an average of 1.1 fatalities year1 over the past 20 years.
The increase in shark attacks over the past two decades is consistent with international statistics of shark attacks increasing annually because of the greater numbers of people in the water.
Over the 218 years for which records were available, there have been 592 recorded unprovoked incidents in Australian waters, comprising 178 fatalities, 322 injuries and 92 incidents where no injury occurred.
Most of these attacks have occurred since 1900, with 540 recorded unprovoked attacks, including 153 fatalities, 302 injuries and 85 incidents where no injury occurred.
Attacks have occurred around most of the Australian coast, most frequently on the more densely populated eastern coast and near major cities (Fig. 1).
In the first half of the 20th century, there was an increase in the number of recorded shark attacks, culminating in a peak in the 1930s when there were 74 incidents (Fig. 2).
The number of attacks then dropped, to stabilise ,35 incidents per decade from the 1940s to the 1970s. Since 1980, the number of reported attacks has increased to 121 incidents in the past decade (Fig. 2).
There had been a decrease in the average annual fatality rate, which had fallen from a peak of 3.4 year1 in the 1930s, to an average of 1.1 year1 for the past two decades.
The number of fatal attacks relative to the number of total attacks per decade has also decreased over this period, from 45% in the 1930s to 10% in the past decade. These declining chances of a shark attack resulting in fatality are also reported elsewhere in the world (Woolgar et al. 2001; Burgess 2009).
In the 20-year period of the 1930s and 1940s, the fatality ratio was 1:2.4 incidents. In the past 20 years, the fatality ratio has been 1:8.5 incidents.
Comparison of attacks per capita indicated that the number of incidents was highest in the 1930s, at 10 attacks per million people per decade, decreasing to an average of 3.3 attacks per million people per decade until the 1990s.
The past two decades have exhibited an increase in attacks, up to 3.5 attacks per million people per decade (1990–1999) and 5.4 attacks per million people per decade 2000–2009 (Fig. 3).
In the 20 years since 1990, there have been 186 reported incidents, including 22 fatalities (Table 1).
This represents a 16% increase in reported attacks during 1990–1999 and a 25% increase over the past 10 years (Fig. 3).
The majority of attacks occurred in New South Wales (NSW) with 73 incidents (39%), then Queensland with 43 incidents (23%), Western Australia (WA) with 35 incidents (19%), South Australia with 20 incidents (11%), Victoria with 12 incidents (6%), Tasmania with two incidents (1.5%) and Northern Territory with one incident (0.5%)
Patterns of attack have changed substantially over time as a result of the changing population and human behaviour.
If human activity related to water-based activities and the use of beaches, harbours and rivers continues to change, we can expect to see further changes in the patterns, distribution, frequency and types of attacks in the future.
Encounters with sharks, although a rare event, will continue to occur if humans continue to enter the ocean professionally or for recreational pursuit.
It is important to keep the risk of a shark attack in perspective. On average, 87 people drown at Australian beaches each year (SLSA 2010), yet there have been, on average, only 1.1 fatalities per year from shark attack over the past two decades.
It is clear that the risk of being bitten or dying from an unprovoked shark attack in Australia remains extremely low.
According to Taronga Conservation Society there have been 216 recorded unprovoked shark attacks in New South Wales in the last 100 years of which 48 were fatal. 


The unintended impacts of shark mesh was on show on Saturday, with a juvenile humpback whale becoming entangled in a net near Coolangatta on the Gold Coast. The calf's mother helped keep the animal near the surface long enough for a patrol to arrive and cut the whale free. [The Sydney Morning Herald, 15 October 2016]

in 1951, New South Wales recorded its worst year of shark encounters at netted beaches, with three separate incidents, including the fatality of local surf ski champion Frank Olkulich (21) who was fatality bitten at a Newcastle Beach called Merewether while treading water……In the 23 years, since September 1992, there has been 21 unwanted shark encounters at netted beaches in NSW; almost one per year*. This doesn’t include the death of a 15-year old boy who drowned after being caught in a shark net at Shoal Bay in March 2007.[3] It does however include the shark incident on 12 February 2009 at Bondi Beach when Glen Orgias (33) lost his left hand after being bitten by a 2.5m white shark while surfing and the severe bite that Andrew Lindop (15) received by a suspected 2.6m white shark at Avalon Beach on 1 March 2009……In January 2012, surfer Glen Folkard was severely bitten by a bull shark at Redhead Beach, north of Sydney. This incident is still waiting a review by DPI, New South Wales, and, along with another two unwanted shark encounters at meshed beaches, was meant to be part of the programme’s 5-year review in September 2014. At the time of this article, this review has still not been finalised. [Sea Shepherd, 5 August 2015]

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