14-km iceberg cut off food supply, causing 69% drop in Antarctic penguin chicks

A 14-kilometre iceberg cut off food supply to an emperor penguin colony at Antarctica's Coulman Island.

Chick numbers dropped by 69% in the 2025 breeding season, with only 6,658 live chicks recorded.

The iceberg calved in March 2025 and drifted towards Coulman Island, blocking the colony's route to feeding grounds.

Parents had to travel farther to find food, impacting chick survival.

The research was published in Communications Earth & Environment.