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Turtles and unexploded bombs prove to be happy bedfellows

THIS dry season, the cycle of life has continued as normal for the flatback sea turtles that nest on Bare Sand Island, a deserted patch of sand dunes off the coast west of Darwin.

Females of the vulnerable species have laid their eggs on the beach at night, oblivious to daytime efforts to search for unexploded bombs. From 1945 to 1979 the island was part of a practice target range used by the air force. A three-year clean-up project, begun in May by the Department of Defence, has already unearthed four large bombs that were still ''in fair condition'', as well as an abundance of empty cartridge cases and projectiles.

While its violent past may make Bare Sand Island seem a poor spot for a turtle nursery, the opposite has been the case.

Jess Abrahams, the northern marine campaigner for the Australian Marine Conservation Society, said a lack of predators on the barren island, such as dogs, dingoes and large lizards, has resulted in it having a very high success rate for hatchlings.

The flatbacks, which nest close to the shoreline, have also coexisted uneventfully for decades with the unexploded ordnance buried further inland.

Instead, many of the threats to the turtles lie offshore.


Mr Abrahams said that it was disappointing that the important breeding ground would not be protected by a network of marine reserves proposed by the federal government for the north-west and north of the continent.

Only 3 per cent of northern waters would be fully protected by the draft plan, he said. ''The sea turtles hatching on Bare Sand Island, which then swim into the Timor Sea, have been left vulnerable to oil spills, seabed mining, and commercial and recreational fishing by this inadequate proposal.''

Other endangered turtle species, such as the green and hawksbill, also feed on nearby shallow reefs. ''The area is incredibly rich in marine biodiversity,'' he said.

The federal Environment Minister, Tony Burke, announced eight proposed marine reserves in northern waters - covering almost 122,000 square kilometres - in August and the plan is open for community feedback until November 28.

Mr Burke said the government had developed its draft plan after consulting environmental groups, the fishing industry, recreational fishers and other marine users, and it covered major habitat for flatback, green and hawksbill turtles, dugongs and sawfish in the north.

As part of the project to clear Bare Sand Island and two other islands of unexploded ordnance, defence contractors first marked them with a network of grids and used hand-held electromagnetic equipment to search down to half a metre.

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