A new study on king penguins (Aptenodytes patagonicus) has found that these seabirds prioritize prey accessibility over sheer abundance when foraging, challenging a long-held ecological theory. The research, published in the journal Ecology Letters on July 10, 2026, used GPS trackers and underwater cameras to monitor penguin foraging behavior near the Crozet Islands in the southern Indian Ocean.
Scientists from the University of Oxford and the French National Centre for Scientific Research (CNRS) observed that penguins consistently chose to hunt in areas where prey, such as lanternfish and squid, were easier to capture, even when those areas had lower overall prey density. This contradicts the classic 'Ashmole's halo' hypothesis, which posits that large seabird colonies deplete nearby food resources, forcing birds to travel farther to find abundant prey.
Lead author Dr. Emily Carter of Oxford University stated, 'We found that king penguins are not simply following the highest concentration of fish. Instead, they are making complex decisions based on the energetic cost of capturing each prey item. This suggests that the structure of the marine environment, including factors like water clarity and prey depth, plays a more critical role than previously thought.'
The study tracked 50 penguins over two breeding seasons, recording over 10,000 foraging dives. The data showed that penguins traveled an average of 30 kilometers from their colony, but selected foraging sites based on the ease of prey capture, not the total biomass available. This behavior has implications for understanding how seabird populations will respond to climate change and shifting prey distributions.
Dr. Carter added, 'If penguins are limited by accessibility rather than abundance, then changes in ocean conditions that affect prey behavior or distribution could have a disproportionate impact on their foraging success. This is a crucial insight for conservation efforts in a warming world.'
