Massive iceberg A-23A on the move again—is it a threat to penguin habitats?

The world’s largest iceberg, A-23A, which broke off from Antarctica, has begun moving again. Roughly the size of the U.S. state of Rhode Island and weighing one trillion tons, the massive iceberg is now slowly drifting towards South Georgia Island, raising concerns about its potential impact on local wildlife and marine ecosystems.

Could Iceberg A-23A Collide with South Georgia?

For the past eight months, A-23A was trapped in Antarctic currents, but it has recently resumed movement at a speed of approximately 1 km per hour. Scientists estimate that it could reach South Georgia’s continental shelf within two weeks.

Researchers warn that if A-23A reaches South Georgia, it may disrupt ocean currents, affecting food availability for wildlife such as seals and penguins. Similar incidents in the past have had severe ecological consequences. In 2004, a large iceberg collided with the island, causing a drastic decline in the survival rate of young penguins and seals due to food shortages.

Dr. Andrew Myers, an oceanographer at the British Antarctic Survey (BAS), cautioned that A-23A could alter ocean circulation patterns, creating serious challenges for local wildlife, especially for seal and penguin populations that are currently in their breeding season.

However, some experts believe that the iceberg may break apart or melt before reaching South Georgia. Dr. Jan Lieser from the Australian Antarctic Program Partnership noted that "A-23A could fragment into smaller pieces and dissipate," adding that a 80-square-kilometer chunk had already broken off recently.

Link Between Climate Change and Iceberg Movement

Many scientists believe that A-23A’s movement is not just a natural phenomenon but is influenced by climate change. Rising sea temperatures around Antarctica contribute to iceberg calving and movement, making such events more frequent in the future.

South Georgia Island is home to 95–98% of the world’s fur seals and serves as a key habitat for penguins and seabirds. The potential impact of A-23A’s movement on this fragile marine ecosystem requires ongoing scientific research and monitoring.

In 2021, another iceberg, roughly the size of the U.S. state of Delaware, was on course to collide with South Georgia but broke apart before impact.

With continued monitoring efforts, international research teams are using satellites and oceanic sensors to track A-23A in real time, studying its movement and assessing potential ecological consequences.