Penguins are considered important sentinel species for monitoring the marine ecosystems of the Southern Hemisphere. As charismatic umbrella species that when protected help protect their ecosystems and associated services, penguins can function as ambassadors with a vital role in raising awareness about marine life and environmental issues.
In this study, researchers used GBIF-mediated species occurrences of 18 extant species in combination with data on climatic and human stressors to quantitatively assess their impact on global penguin populations.
First, the authors identified 22 penguin distribution hotspots, most of which were shared among several species. Four species, Galápagos (Spheniscus mendiculus), African (S. demersus), yellow-eyed (Megadyptes antipodes) and little penguin (Eudyptula minor), did not share their hotspots with other species. A hotspot in the Macquarie Island region (~1,500 km southeast of Tasmania), however, boasted five co-occurring penguin species.
When assessing the cumulative impact of stressors, the authors found the greatest impact in areas off western Africa, Peru, the Patagonian Shelf and waters around New Zealand and south and east Australia. Within penguin hotspots, the most significant contributor were changes to sea surface temperature.
African (S. demersus), chinstrap (Pygoscelis antarcticus) and Humboldt penguins (S. humboldti) came out as the most potentially impacted of all species, while erect-crested (Eudyptes sclateri) and king penguins (Aptenodytes patagonicus) were the least impacted by environmental and human stressors.