The number of endangered dolphins, turtles, sharks and rays drowning in shark nets off the Australian coast has risen to what conservationists say are “shocking” levels.

In all, 284 dolphins, turtles, sharks and rays were killed in the nets in the latest annual season, according to official data.

Nets are designed to kill sharks to allow swimmers to go into the sea without fear of being bitten, but they are also fatal to many other species, including certain sharks that are harmless to humans.

In New South Wales, there are 51 shark nets installed at numerous beaches, including at all those in Sydney.

Some 480 animals were caught in nets between September last year and April, the newly released data shows.

Of those that died, 183 were classified as threatened or protected, including seven dolphins, six turtles and 14 grey nurse sharks, described as “critically endangered and harmless”.

In addition, 179 rays were also found entangled. Conservationists say even animals released from nets alive may die soon afterwards from the stress and injuries.

Nicola Beynon, of Humane Society International (HSI)/Australia said the figures revealed “a shocking wildlife death toll” and that the death of 14 grey nurse sharks in particular would have a “really significant” impact.

“The recovery plan for the grey nurse shark says the death of just one individual on the east coast is significant because the species is so endangered,” she said.

The Australian government says that despite their appearance "grey nurse sharks are not a threat to divers or swimmers and actually have a very placid nature.”

A survey in 2000 showed their numbers in New South Wales (NSW) could be as low as 292.

The charity, together with the Australian Marine Conservation Society, is calling for the New South Wales government to end the shark-meshing scheme, which they say do nothing to reduce the risk of unprovoked shark injuries to swimmers.

Leonardo Guida, a shark scientist at the society, said: “The only guarantee we have from these nets is the drownings of iconic wildlife like dolphins and turtles. For over 80 years in NSW, tens of thousands of animals have drowned at netted beaches.

“Shark nets were removed along the north coast of NSW because the local communities opposed the unacceptable wildlife death toll. Newcastle, Sydney and Wollongong need to do the same. This must be the last meshing season.”

The trial on the north coast in 2017-18 of newly installed shark nets found that 97 per cent of animals caught were “non-target species” – harmless to bathers. The trial was abandoned after widespread protests.

Government officials in the state have developed other ways to reduce the risk of shark bites, such as more drone surveillance, personal deterrents and education schemes for swimmers.

In Queensland, which also has shark nets, the government lists 19 species of shark on its target list. A scuba diver there was killed last month.

Two swimmers were critically injured in attacks in the waters of the Great Barrier Reef in 2018.

Lawrence Chlebeck, of HSI/Australia, said the alternatives were more effective than nets. “Shark nets are a relic of the past, having been introduced in the 1930s when little was known about shark behaviour and their importance in the ecosystem. Nets don’t make swimmers safer but take a terrible toll on marine life.”

The two organisations point to a recent court tribunal decision over the nets, which stated: “The lethal component of the shark control program does not reduce the risk of unprovoked shark interactions. The scientific evidence before us is overwhelming in this regard.”

In the previous season, 2018-19, 395 animals were reported to have been caught in the nets; 372 of them were “non-target” species, and 179 were either threatened or protected. Seven dolphins were killed, six turtles died, and 199 “non-target” sharks were killed.

In the 2017-18 season 403 animals were captured in nets – an increase of 30 on the previous year. Of those, 369 were “non-target species” and most were threatened and/or protected); some 223 were killed.

Ms Beynon said then: “Every year the NSW Department of Primary Industries releases these shocking statistics, and every year the NSW government decides to put the nets back in the water. This year they must surely reconsider.”

The Independent has asked the New South Wales government to respond.

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