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Our previous experiment, published in 2022, showed that urban herring gulls perceive men shouting as a threat. When we played back recordings of men shouting “No! Stay away! That’s my food, that’s my pasty!”, gulls moved away, just like they did in response to our playback of another gull’s alarm calls that signal danger.
These findings made us wonder whether gulls foraging in towns are fearful of human vocalisations in general, or whether they are sensitive to the way we speak to them.
Recent studies have indicated that gulls pay attention to subtle human cues, like our gaze direction and handling of food items. They even colour-match the crisp packet we’re eating from when given the choice between two differently coloured options. Given how attuned urban gulls seem to be to our behaviour, my colleagues and I predicted that they would be similarly sensitive to our sounds.
We asked five British men to record themselves saying “No! Stay away! That’s my food, that’s my pasty!” in a shouting voice, and then a second time in a neutral, “speaking” voice. We used male voices in our experiment as most wildlife crimes against gulls reported in the media are committed by men. Although we did not test this, it seems likely that gulls are more wary of men’s voices compared to women’s voices – as found in nestling jackdaws as well as in African elephants. Men are more likely to represent a threat to these animals than women or children.
We also needed to check whether the gulls showed fearful behaviour to sound played from our speaker in general. So, as a control trial, we used the song of European robins (of which we downloaded five recordings from the Xeno-Canto library). We edited these sound clips (five per treatment) so that they were all of the same duration (30 seconds) and volume when played back to our gull test subjects.
We conducted all our experimental trials in Cornish coastal towns where gulls are known to take food from people – it was these bold individuals we were most interested in testing for their responses to human sounds. We started each experimental trial by luring a gull to the ground with a clear, sealed plastic container filled with fries. Once the gull approached the container, we started a 30-second playback of one of our three treatments: a man speaking, a man shouting the same words or a robin singing.
We found that gulls exposed to the shouting and speaking treatments were significantly more likely to flinch, to stop pecking at the food container and to leave the area, compared to gulls exposed to robin song. Of the gulls that left the area, those that were shouted at would most often fly away, whereas gulls that were spoken to tended to waddle away. These findings suggest that urban herring gulls pay attention to our tone of voice and are more likely to leave in a hurry when addressed angrily.
Our results may not surprise you. Dog owners may tell you that dogs respond to the way we talk to them, and often look “guilty” when we scold them. Domestic horses can also tell the difference between positive and negative human vocalisations. They freeze for longer when they hear human growling than human laughter.
However, we have domesticated these species for thousands of years, while herring gulls have only started breeding on our roofs in the last century. It therefore seems likely that gulls have learned to associate our aggressive or angry intonations with threat. For gulls, being shouted at is more commonly associated with being chased than with being fed, after all.
Herring gulls might give the impression that they are thriving, given their apparent abundance in coastal towns in summer. But they are on the RSPB’s red list of species of highest conservation concern. Their coastal population is only half of what it was 50 years ago. This is probably due to a combination of fish depletion, disturbance, culling, disease and egg predation by animals like rats and foxes.
But my team’s research points to easy, non-violent ways we can mitigate conflict with a species that is just making the best of a bad situation. For example, in 2019, we found that simply staring at herring gulls can get them off your food. And we know that gulls go where the food is. So another important thing you can do is not feed them.
Neeltje Boogert is a Royal Society Dorothy Hodgkin Research Fellow at the University of Exeter.
