The trillion-ton slab of ice, called a megaberg, could slam into South Georgia Island and get stuck or be guided around it by currents.

In 1902, British explorer Robert Falcon Scott spotted a large group of large black and white birds at Ross Island, Antarctica. This was among the many milestones of Scott’s famous Discovery expedition: the first breeding colony of emperor penguins. Now, only 124 years since this penguin colony was discovered, emperor penguins have officially been listed as endangered, along with the Antarctic fur seal. As the world warms, Antarctic krill are shifting southwards and sea ice is shrinking at record levels. And these unprecedented changes are having a domino effect on these species. These are the first penguin and pinniped – marine mammals that have front and rear flippers – to be given this conservation status in the Southern Ocean. Their perilous situation is a critical turning point, and shows how rapidly the Antarctic environment is changing. At the same time, the spread of highly contagious avian influenza, or bird flu, adds a new and immediate threat to Southern Ocean wildlife, compounding the pressures of climate change on stressed species. Dramatic declines linked to climate change The first emperor penguin breeding colony was discovered at Cape Crozier, on Ross Island, during Robert Falcon Scott’s Discovery expedition in 1902. A decade later,...