Another expert says drone technology may have prevented shark attack at Coogee beach on Saturday

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A shark behaviour expert says Tony Abbott “doesn’t understand the science” after the former prime minister called for sharks to be culled in the wake of an attack at a Sydney beach.

Leah Stewart, a 35-year-old woman, was bitten on the leg and arm by what was thought to be a great white shark on Saturday morning.

Exclusive A vast area of the Bellingshausen Sea should be covered by sea ice by now, with one expert calling the loss of ice ‘depressing’

Antarctica’s west coast is missing an area of winter sea ice the size of France, sparking concerns for threatened penguins other marine life and global sea levels.

One expert said the loss of ice in the Bellingshausen Sea was “depressing” and the failure of ice to form could have intensified a heatwave over the continent’s peninsula last week that saw daytime temperatures peak at 15.4C which is more than 20C above average.