Emperor penguins depend on stable Antarctic sea ice for breeding and raising chicks; unprecedented sea ice loss in 2023 caused near-total breeding failure across multiple colonies, signalling a climate crisis for the species.
The 2023 breeding failure provided a real-time welfare crisis at landscape scale. Chicks that had survived months of parental brooding and feeding fell into the freezing Southern Ocean when ice broke up before their feathers were waterproof, drowning within hours. The helplessness of adult birds that could not prevent this outcome, and the loss of their breeding season investment, represents a profound disruption of one of the most remarkable life histories in the animal kingdom. Adults that survive colony failure must undertake their energy-intensive annual moult with bodies depleted from a breeding season that produced no offspring. Repeated breeding failures reduce lifetime reproductive success and eventually population viability. The welfare of emperor penguins is directly determined by greenhouse gas emissions decisions made by humans thousands of kilometres from Antarctica.