Antarctic penguins emit up to 7 million tonnes of methane a year, study finds

Research from the Institute of Marine Sciences of Andalusia (ICMAN) and the University of Granada has revealed that large colonies of chinstrap penguins in Antarctica contribute a significant amount of methane to the atmosphere. Methane, a potent greenhouse gas, has a greater impact on global warming than carbon dioxide. The study, published in the journal Climate and Atmospheric Science, estimates that the guano produced by these penguins generates around 490,000 tonnes of methane annually.

This is comparable to emissions from other recognized natural sources, such as all the world's coastal ocean areas. Prior to this study, most methane emissions research had focused on human activities, such as fossil fuel use, agriculture, and waste management, as well as domesticated animals.

The guano that accumulates in these bird colonies, which can house tens of thousands of individuals, creates intense methane emission hotspots. These hotspots have never been measured or quantified until now. The research team conducted direct gas measurements in two large penguin colonies on Deception Island in the South Shetland Islands archipelago.

They also utilized drones with optical sensors to map the guano-covered surfaces and estimate the populations. If these findings are extrapolated to all Antarctic land areas influenced by penguins, emissions could reach up to 7 million tonnes of methane per year. This amount is comparable to global estimates for other major methane sources associated with animal activity, such as termites.

The authors of the study believe that this phenomenon should be included in global emissions inventories. They also emphasize the need to study how climate change could affect this emission process by impacting both penguin populations and the soil microorganisms responsible for methane production as the guano decomposes.