University of Sussex
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Dataset for "Inter-species stimulus enhancement: Herring gulls (Larus argentatus) mimic human food choice during foraging"

posted on 2023-05-23, 08:33 authored by Paul GrahamPaul Graham, Franziska Feist, Kiera Smith

Dataset for paper published in Royal Society Biology Letters (May, 2023)

The datasheets contain the record of attentional markers, per bird for the primed and free choice conditions.The attentional markers were head turns, approaches and pecks.

Sheet 1: 2022

Head turn data was only collected in 2022; thus only n=93.

Used for analysis of differences between FC, PC1 and PC2, and for differences in head turn frequency by age.

Condition = Condition type (PC1, primed condition 1; PC2, primed condition 2; FC, free condition)

PC1 and PC2 were summed due to insignificant differences between them -> PC.

Average_Head_turns_per_minute = average number of head turns counted per minute the individual was in camera view

For Approaches and Pecks:

No = no peck/approach occurred

Yes = approach/peck occurred irrespective of colour-match

Cor = peck at/approach towards the crisp bag that colour-matched the hand-held one

NCor = peck at/approach towards the crisp bag that did not colour-match the hand-held one

Both = both colour-matched and non-colour-matched approach/peck occurred

Approach_YN and Peck_YN are occurrences of approaches and pecks irrespective of whether they occurred towards the biased side.

Sheet 2: 2021 and 2022 summed

Combined peck and approach data from 2021 and 2022; thus n=183.

Used for analysis of approach and peck occurrence, age differences in approaches and pecks, as well as investigation of whether gull choices matched the hand-held item.

Held_Item and Pecked_Item are the colours of the crisp bags (blue and green) held by the experimenter and chosen by the gull, respectively.

This was used to test whether Held_Item influenced Pecked_Item 


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 gull’s 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 demonstrator’s 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.