Reducing penguin numbers may exacerbate climate change | the animals

Iron is a critical component of Southern Ocean ecosystems. It is a food source for many phytoplankton in the ocean. Penguins play a crucial role in this, according to a study published Tuesday in Nature Communications, because they eat plankton and their droppings are released back into the water.

Researchers calculated the volume of feces, or guano, from a colony of chinstrap penguins on Deception Island, off the coast of the Antarctic Peninsula, by processing drone images with artificial intelligence. Thanks to chemical analyzes of this guano, they found a very high concentration of iron, about 3 milligrams per gram.

If these figures were extrapolated to the entire population, this would amount to 521 tons of iron per year. Penguins are therefore an important player in the iron cycle, but their contribution has halved in the past 40 years, as has populations.

The oceans annually ‘capture’ a third of the carbon dioxide emitted into the atmosphere thanks to the photosynthesis system by phytoplankton. Whales also play their role by eating krill, but the role of seabirds such as penguins has not yet been studied.

Unlike whales, which spend their lives in different parts of the oceans, penguins often stay in the same place throughout their lives. “They provide more concentrated iron recycling in the places where they reside,” says Oleg Belyaev, one of the study’s authors and researchers.

The population collapse of these birds, along with climate change, has the authors concerned about a potential problem in the balance of the Southern Ocean ecosystem and its ability to store carbon dioxide from the atmosphere. “This research aims to make people aware of the ecological importance of these seabirds,” Believ concludes.