• Fact: Shark nets do not provide a complete barrier. "The shark mesh nets do not act as a complete barrier to sharks reaching beaches as they are not permanently set in the water, do not cover the whole length of the beach, and do not extend from the water surface to the seabed. In fact, approximately 40% of shark entanglements occur on the beach side of the nets, because sharks are able to swim over and around the nets." – Point two in the Fisheries Scientific Committees listing of shark meshing as a key threatening process
Source: http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0005/208319/FR24-shark-meshing.pdf
Image source: http://www.abc.net.au/science/articles/2002/03/07/2116717.htm
• Fact: Open water shark mesh nets are different to small-meshed shark-proof swimming enclosures in estuaries. These form a true barrier running surface to bottom and strung with both ends to shore. The small mesh size ensures that sharks are not caught or injured, but also means they cannot be used in open water where the nets could be damaged or destroyed by rough surf
• Fact: Shark nets used at open beaches in NSW have holes 50cm wide, large enough to entangle sharks and other large marine species. Shark nets are not intended to form complete barriers, but reduce the risk of attack by catching and killing sharks
Source: http://www.abc.net.au/science/articles/2002/03/07/2116717.htm
Misconception 2 – Shark nets act as a deterrent to shark migration patterns as sharks actively avoid the nets
• Fact: No evidence exists to support this hypothesis. First proposed in a paper by Reid and Krogh (1992, p232), they immediately discard it in the next sentence of the paper, stating that the random temporal placement of nets and varying positions of nets on different days do not support the view that sharks actively avoid nets. Currently the hypothesis still remains unfounded. The sole function of these nets is to kill sharks and reduce their population.
Misconception 3 – The risk of shark attack in Australia, particularly around NSW is very high and therefore killing sharks as well as harmless bycatch is a justifiable risk reduction.
• Fact: Since 1970, shark attack fatalities in Australia have averaged 1.1 per year. In the last 36 years, the NSW population and tourist numbers have increased significantly. In this period there have been only 4 shark-attack fatalities.
• Fact: In other cities such as Florida, America there are numerous shark attacks every year. Despite this, shark nets and culling have never been adopted with the public accepting the risk.
• Fact: In Australia no attempts have been made to quantify the actual risk of shark attacks in terms of numbers of swimmers for a given period of time in a specific area. Thus we have no way of knowing whether the risk of shark attack is increasing, decreasing or remaining level
Misconception 4 – The removal of shark nets will result in a rapid increase in the number of shark attacks. The reason there are no shark attacks today is that shark nets are protecting our beaches.
• Fact: Sharks have very low reproductive potential, only laying a few eggs. Because of this it takes a long time for reduced shark populations to recover, and is why shark numbers are declining worldwide.
• Fact: Shark populations today are very much lower than they were in the 1930s when attacks were more frequent
• Fact: Shark populations were abnormally high in the 1930s due to remains from the Homebush abbatoir flowing out to sea, changing migration patterns. As these human related food sources are no longer available, it is unlikely that shark populations will ever reach those numbers again.
Source: Paxton, J. Misconceptions about Shark Attacks and N.S.W. Shark Meshing (2006) Australian Museum, Sydney.
Accessible online http://nccnsw.org.au/index.php?option=com_docman&task=doc_details&gid=237&Itemid=99999999
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