Penguin poo snow melt is accelerating across parts of Antarctica, according to new research that links penguin guano to faster-thawing snow through blooms of snow algae.
Snow algae are microscopic, single-celled plants that survive some of the planet’s coldest conditions. When nutrients are limited, the algae produce red pigments that protect cells from sunlight and slow growth. In nutrient-rich conditions, the algae shift into a growth mode, packing cells with green chlorophyll to maximize photosynthesis.
Snow dominated by green algae absorbs far more solar energy than snow tinted red, which means it warms and melts more quickly. The new study set out to quantify how penguin waste influences that shift.
Alia Khan of the University of Colorado and colleagues sampled red and green snow along the coast of the West Antarctic Peninsula, collecting from areas with and without nearby penguin colonies. The team found that penguins track guano across snowfields, unintentionally fertilizing algae and promoting green blooms that increase how much sunlight the snow absorbs.
The results, published in the Journal of Geophysical Research: Biogeosciences, indicate that penguin activity can amplify local melting by boosting green snow algae. Projections of Antarctic melt do not currently account for this pathway, the researchers noted, and it could become more significant as penguin populations shift farther south with warming temperatures.
How penguin poo snow melt intensifies
The mechanism is straightforward, scientists said. Nutrients from guano spur algae to grow greener, the darker snow surface takes in more solar energy, and melt rates climb. As penguins waddle into new territory closer to the South Pole, the area influenced by this fertilization effect could expand.
For Pacific communities, including Hawaiʻi with strong ties to polar research and sea level science, the findings add another nuance to understanding how biological processes can interact with climate to shape future ice and ocean conditions.
