Structured aggression and dominance dynamics in long-lived colonial African penguins (Spheniscus demersus)

This study provides rare evidence from a long-lived seabird in captivity, extending insights beyond the short-lived model species that dominate social research. By mapping aggressive interactions as social networks, we demonstrate that dominance rank in African penguins is not determined solely by age or sex: rearing conditions exert long-lasting effects on an individual’s position in the hierarchy. Contrary to the common assumption that artificial rearing impairs social competence, hand- and mix-reared birds consistently outperformed their parent-reared conspecifics. Our results also reveal the dynamic role of age, showing that younger penguins can dominate older individuals, reshaping how we understand the formation of social hierarchies. These findings have direct implications for conservation and zoo management, offering new strategies to improve welfare and social stability in captive penguin populations.