How an iceberg may have stopped emperor penguins from breeding on Coulman Island in 2025

The number of chicks in the Coulman Island emperor penguin colony decreased by about 69% in 2025 compared with 2024, according to research published in Communications Earth & Environment. The authors suggest that a large iceberg, which grounded off the island between July 2025 and January 2026, likely restricted the colony's access to important foraging areas, demonstrating that individual iceberg movements may affect breeding success even when overall sea ice conditions appear favorable.