WORRIED about how to protect your seaside chips from seagulls? Scientists believe the answer lies in an old-fashioned stare down.

The feathered thieves are more likely to strike when they can swoop in under the radar, avoiding the gaze of their victims, researchers say, while staring at the birds makes them less likely to steal your food.

University of Exeter researchers put a bag of chips on the ground and tested how long it took herring gulls to approach when someone was watching them. They compared this to how long it took when the person looked away.

On average, the gulls took 21 seconds longer to approach when being watched. However, the researchers were hampered by the reluctance of some gulls to participate. They attempted to test 74 gulls, but most flew away or would not approach.

Only 27 approached the food, and 19 completed both the “looking at” and “looking away” tests. The findings focus on these 19 gulls.

Lead author Madeleine Goumas, of the Centre for Ecology and Conservation at Exeter’s Penryn Campus, said: “Gulls are often seen as aggressive and willing to take food from humans, so it was interesting to find that most wouldn’t even come near during our tests.

“Of those that did approach, most took longer when they were being watched. Some wouldn’t even touch the food at all, although others didn’t seem to notice that a human was staring at them.”

Goumas added that the team did not look at why individual birds were so different, but it may have been because some might have had positive experiences of being fed by humans. “It seems that a couple of very bold gulls might ruin the reputation of the rest,” she said.

The researchers say their study shows any attempt to manage nuisance behaviour by treating all gulls as being alike could be futile.

The researchers will next investigate how eating human foods affects gulls and their chicks in the long term. The study is published in the journal Biology Letters.