Feist, F. | Search bioRxiv

bioRxiv2022

Inter-species stimulus enhancement: Herring gulls (Larus argentatus) read human behaviour during foraging

Herring gulls are one of the few species that thrive in anthropogenic landscapes and their familiarity with people makes them an excellent target for studies of inter-species social cognition. Urban gulls pay attention to human behaviour in food-related contexts and we set out to investigate whether such cues can be used to redirect a gulls attention to potential food items in their environment. Herring gulls were given free choice of two differently coloured anthropogenic food items in the presence of a demonstrator, who was either sitting still or pretending to eat food from an item that matched one of the secondary food items. We found that a demonstrator mimicking eating significantly increased the likelihood of an approach or peck. Furthermore, 95% of pecks were directed towards the secondary food item which colour-matched the demonstrators food item. The results show situation-dependent attentional modulation in gulls, whereby gulls are able to use human cues for stimulus enhancement and foraging decisions. Given the relatively recent history of urbanisation in herring gulls, this cross-species social information transfer is likely to be a by-product of the cognitive flexibility inherent in kleptoparasitic species.

animal behavior and cognition↗

bioRxiv2022

An Ethogram Identifies Behavioural Markers of Attention to Humans in European Herring Gulls (Larus argentatus)

Herring gulls are one of few species thriving in anthropogenic landscapes. Their history of urbanisation and familiarity with people makes them a good target for studies of human-wildlife interactions. Previous research highlights a connection between food-stealing behaviour, success in anthropogenic areas, and increased attention towards humans, raising questions about the exact extent of a gulls knowledge of human food cues. To explore these, behavioural responses to human cues in a food-related context were investigated and presented in a systematic ethogram, which identified three distinct markers of attention. Head turns, approaches, and angular body position all differed significantly between control and food conditions, showing that attention towards humans in a food-related context was upregulated and reflected in behaviour. In food condition trials, head turns occurred more often and gulls faced towards the experimenter with occasional approaches that were never seen in control conditions. Additionally, juvenile gulls exhibited less head turns, indicating lower vigilance, while neither approaches nor pecks differed between age groups. Interestingly, no group effects on attentional markers were found. Acoustic and behavioural human food-like cues alone seemed insufficient to elicit these responses, indicating that gulls specifically paid attention to the details of human behaviour. These results show situation-dependent attentional modulation in gulls and provide a description of attentive behaviours that can be used in further study. SummaryUrbanised herring gulls successfully benefited from anthropogenic food sources. We showed that human food-centred behaviours directly modulated the attentional states of gulls.

animal behavior and cognition↗