Shark net
[1][2] The nets in Queensland, Australia, are typically 186m long, set at a depth of 6m, have a mesh size of 500mm and are designed to catch sharks longer than 2m in length.
[3] The nets in New South Wales, Australia, are typically 150m long, set on the sea floor, extending approximately 6m up the water column, are designed to catch sharks longer than 2m in length.
[9] The large mesh size of the nets is designed specifically to capture sharks and prevent their escape until eventually, they drown.
In March 1935, for example, two people — one at North Narrabeen and one at Maroubra — perished after great white shark attacks in a single week.
The meshing was never designed to enclose a piece of water, as barrier nets couldn't survive a surf zone.
But over time, even without adjusting for the spread of the program across almost all Sydney beaches and into Wollongong and Newcastle, the catch declined.
Today's New South Wales meshing annual average catch is 143 sharks, many of which are released alive.
[13] Shark nets result in incidence of bycatch, including threatened and endangered species like sea turtles, dugongs, dolphins and whales.
[16] New South Wales and Queensland also utilize acoustic pingers attached to the nets to reduce bycatch of dolphins, whales and other marine mammals.
[13] They suggest alternatives such as surf lifesaving patrols, public education on shark behaviour, radio signals, sonar technology and electric nets.
Political scientist Christopher Neff notes, "Internationally, shark nets have been labeled a 'key threatening process' for killing endangered species."
He adds: " ... killing endangered species to boost public confidence or to show government action is not workable.
We continue our stance against shark nets and maintain our rescue operations to save dolphins, whales, turtles that become entrapped within them, along with working with the authoritative agencies to research improved methods which will lessen the impact on our marine life".
[29] The NSW prawn trawling industry alone results in 64 tonne of shark as bycatch each year,[16] with two thirds dying.
[30] Tuna and swordfish longline fishing off the coast of South Africa reported 39,000 to 43,000 sharks died each year between 1995 and 2005.
[30] Sharksavers estimates that in total 50 million sharks are caught unintentionally each year as bycatch by the commercial fishing industry.
Nets are lifted every 24 to 48 hours for servicing so as to prevent rotting, to clean out debris and to remove dead sharks and other marine life.
The department states that the nets have "never been regarded as a means of absolutely preventing any attacks", but help to deter sharks from establishing territories.
They include the following: A fatal attack in Queensland occurred in January 2006 at Amity Point on North Stradbroke Island.
