SDG 15 | ECOSYSTEM LIFELand Issues
The increase in temperatures in the Antarctic Peninsula and the melting of ice have caused movements in the colonies of these birds
The discovery of a new penguin colony should be cause for joy among biologists and other experts, but the reality is totally different. “What this new presence indicates is a notable effect of climate change in that area,” warns Andrés Barbosa, a researcher at the National Museum of Natural Sciences of the Higher Council for Scientific Research (CSIC).
This new colony is of Juanito penguins (Pygoscelis papua under its scientific nomenclature) and the remote place is Andersson Island, in the Antarctic Peninsula. A Greenpeace Arctic Sunrise expedition corroborated the finding. “We are seeing a process in which this species of penguin is spreading into a new habitat,” warns Louisa Casson, a member of the NGO.
For the first time the red beaks of this species of penguin have been seen in the easternmost part of the Antarctic Peninsula. The juanito are birds that, unlike their other brothers, flee from the cold and frozen lands and waters of Antarctica. “They are breeding further south: a biological manifestation of sea ice loss,” says Casson.
Last summer, the World Meteorological Organization (WMO) issued an alert: “”The Antarctic Peninsula – the northwestern tip of the continent near South America – is one of the areas of the planet in which there is a faster rate of warming : almost 3 °C in the last 50 years”.
“This is the climate crisis happening right before our eyes,” reveals Casson. A risk that is reflected in the daily life of these small birds. Penguins, together with sharks or molluscs, provide an early warning of a danger such as the impacts of climate change”, point out the scientists.
The increase in the temperature of the oceans and the melting of Antarctica has meant that the Papuans “are expanding their distribution area,” says Barbosa. “It is one of the southernmost records for juanito penguins,” Greenpeace officials certify. “Until recently there was too much ice for them to successfully raise chicks,” they add.
Before this discovery, only one solitary gentoo nest had been found this far south, but researchers have now discovered a colony of 75 gentoo chicks on Andersson Island. “The gentoo penguin populations are increasing”, details Barbosa.
disappearance of species
The juanito are an example of adaptation to climate change, but not everyone can say the same. A recent expedition to Antarctica discovered that the chinstrap penguin colonies on Elephant Island had collapsed, “their populations on the peninsula have also decreased considerably due to the decrease in krill (a species of crustacean) derived from climate change” says Barbosa.
As the ice disappears in the Antarctic Peninsula, the Juanito colonize new territories, while the Adelie (Pygoscelis adeliae) recede, since they depend on sea ice for food and reproduction. “It shows a worrying decline in its populations that could lead it to disappear locally in the South Shetlands archipelago,” warns the Spanish CSIC researcher.
The increase in water temperature and melting directly affects their way of life and also their eating habits. “The reason for the changes is mainly related to climate change and the effect that occurs in the decline of krill,” explains Barbosa.
This small, shrimp-like crustacean inhabits the waters of Antarctica and makes up a large part of the aquatic population that the penguins eat. “The increase in temperature means that there is less sea ice, which is where the phytoplankton that the krill feed on develops. Therefore there is less food for the krill and their population is reduced. As a consequence, species highly dependent on this prey such as the chinstrap and Adélie penguin suffer this reduction », he explains.
But, the lack of their main food is not the only problem that these Antarctic birds face. “To the threats that have been mentioned above, we should add contamination,” responds Barbosa.
An investigation led by Barbosa and members of the National Museum of Natural Sciences, of the Higher Council for Scientific Research (MNCN-CSIC), has shown the high content of microplastics, such as polyester and polyethylene, among other particles of anthropic (human) origin, in the body of Antarctic penguins.
The study analyzed the feces of three species of penguins: the Adelie penguin (Pygoscelis adeliae), the Chinstrap (Pygoscelis antarcticus) and the Gentoo penguin (Pygoscelis papua). The results of the analysis show that the diet of the three species is composed of different proportions of krill, 85% in the case of the Adélie penguin; 66% in the chinstrap and 54% in the juanito. “The presence of pollutants in Antarctica is a matter of concern, both microplastics, such as mercury, other heavy metals and also persistent organic pollutants,” he warns.