Urban gulls adapt their foraging behaviour to human activity


By Kelly-Louise Ray, Masters, Biology

Have you ever settled down to enjoy some hot chips, only for a gull to suddenly swoop down and snatch them? Recent research has revealed that gulls are even smarter than we think, as they know when and where to strike in order to increase their chances of a tasty snack.

A team of researchers from the University of Bristol’s Engineering and Life Sciences faculties fitted mini GPS-tracker backpacks to lesser black-blacked gulls to identify three frequently visited sites: a school, a waste centre and Clifton Down.

The researchers combined GPS data with observations at each site: the number gulls, the number of people and whether a human-created food source was present. The results showed that gulls flocked to the school coinciding with the morning and lunch breaks, when students were consuming food.

Speaking to The Guardian, Dr Anouk Spelt, lead author of the paper said: ‘At the school there were not many gulls around until break time. Then you saw them sitting on the rooftops. The moment the bell went off, they all flew up and started looking for leftovers.’

The gulls also targeted the waste centre, mainly visiting between the opening and closing times on weekdays when fresh waste is unloaded.

However, at Clifton Down, the gulls did not correspond with the number of people present – they mainly visited early in the morning, which the researchers attributed to the abundance of earthworms.

Multiple gull species worldwide have moved inland, establishing urban-nesting populations and thriving in these relatively novel environments. Still commonly referred to as ‘seagulls’, the GPS-tracker backpacks revealed that the gulls in this study never visited the sea, despite its close proximity. The gulls spent the majority of their time in the city, leading the researchers to advocate the more apt name of ‘urban gulls’.

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While gulls in urban settlements are thriving and have undergone rapid population increases in the last 40 years, it is not widely known that populations elsewhere are in decline. The reason for their success in urban environments is not well understood and may be due to a number of factors including warmer temperatures, fewer predators and safe rooftop nesting sites.

This study suggests that the ability of gulls to adapt their foraging behaviour according to human activity may be one of these reasons.

So, what can you do to prevent sneaky gulls from stealing your food? One tactic may be to stare them down – researchers at University of Exeter found that staring at herring gulls made them less likely to steal food!

Featured Image: Epigram / Kelly-Louise Ray