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As anyone who has ever had a boardwalk pizza slice snatched from their hand can attest, gulls are a bit of a menace when it comes to food. These birds thrive in human-created areas, where they find lots of things to mooch off us. A new study from researchers at the University of Exeter demonstrated that—at least for the herring gulls of Falmouth and Penzance, two towns in South West England—human touch may be the key to identifying tasty morsels.

“Lots of species haven’t been able to do well in these environments,” says lead author Madeleine Goumas, an animal behavior scientist who studies birds. Herring gulls, on the other hand, “seem to be doing quite well in urban areas, which is interesting for a seabird.” In previous research, Goumas and her coauthors documented that herring gulls are less likely to steal your food while you are staring them down. She did that experiment by putting clear plastic bags containing french fries down in front of different gulls, and then either staring at them or looking away. As she did the experiment, she says, “I was thinking, are they coming over because they just go ‘oh, there are some [french fries] there, or are they thinking… ‘I’ll go and check it out because I’ve seen a human handle it?’” If that was the case, it would mean that the herring gulls had learned to associate humans and food directly. She designed an experiment to find out.

A diagram of a bird
The set-up. Goumas et al

Goumas approached individual adult gulls who were essentially just hanging around. In each instance, she placed two buckets on the ground in front of the gull, equidistant from one another. Underneath each bucket was a packaged blueberry flapjack like this one here—basically, a granola bar in a partially transparent wrapper. “I didn’t want to actually feed the gulls,” Goumas says—human food isn’t great for gulls, and she didn’t want to contribute to habituating them to people further. She also weighted the packages so the gulls couldn’t just fly away with them.

“People get quite annoyed about gulls, and some councils actually have a bylaw saying that you shouldn’t feed them,” she says. She didn’t want her work to encourage more human-gull conflict.

After setting up the buckets and a video camera, she lifted the buckets to reveal the flapjacks. She then picked up one of the flapjacks, still in its package, and handled it for 20 seconds in front of the gull before putting it back down. Then she stepped away and waited for two minutes to see if the gulls approached, recording the whole process on video.

Goumas approached 38 gulls in total. Twenty-four pecked at one of the flapjacks, and 19 of those went for the one Goumas had handled in front of them. At 79 percent, that’s the vast majority of those who bothered to peck. But some did nose the unhandled flapjack: researchers speculate that the sole fact a human was nearby might have made it more attractive to the gulls.

The researchers wanted to check if the same dynamic would play out with non-food objects, so they repeated the experiment in a new area with sponges cut into the shape and size of flapjacks. In that case, 65 percent of the 41 gulls they approached pecked at the sponge that Goumas had handled. The researchers say that’s not much different from the levels you’d expect to see if the two sponges were no different and a gull chose one or the other by chance. While gulls are curious about new objects—something that some other animals might be very wary of—they’re specifically more interested in food people have touched, not just objects we handle.

These results suggest that, for herring gulls at least, human cues can suggest where to find food in human environments. But they might also suggest something broader: “it is highly unlikely that herring gulls are the only wild animals to use human behavioral cues in urban environments,” the researchers write.

Although they might have adapted to live among humans, not every gull is as brave as the ones that Goumas captured on camera. “A lot of gulls did fly away. A lot of them are very nervous,” she says.

Understanding urban animals like gulls could help us do a better job of living alongside them, but Alison Greggor, a San Diego Zoo Global animal behaviorist who studies birds and was not involved in the new research, says it should also enhance our respect for them. “Animals that are living in urban environments are still wild animals,” she says.

Urban wildlife use the behavioral tools they already have—like looking for social cues, which birds are well versed in—to navigate an environment that looks very different than the one they evolved to occupy. “Animals can only survive alongside the changes people make in the environment often by responding behaviorally,” Greggor says. “In my mind, we should give these birds a lot of respect for being able to adjust quickly.”