Seagulls steal your chips because they’re smart, a new study using coloured crisp packets suggests.
University of Sussex scientists say herring gulls are learning how to mimic the food choices of humans, known as ‘stimulus enhancement’.
Using colour to test the stimulus enhancement theory, the researchers positioned one blue crisp packet and one green crisp packet in the immediate vicinity of both individual and groups of herring gulls along Brighton’s seafront.
Nearby, a human experimenter ate from a blue or green crisp packet. The researchers found that the gulls would turn their heads to watch the experimenter and, in most cases, then pecked at the matching crisp packet to attempt to find food.
The research shows that gulls observe humans and the food options they select, and use that knowledge to determine their own food choices.
The researchers point out that this behaviour is a sign of intelligence.
Prof Paul Graham, Professor of Neuroethology at the University of Sussex said: “While we know that animals learn from each other, we rarely see animals learning from a totally different species when it comes to food preferences.
“This interaction with humans is relatively modern, and what we can see is that gulls have adapted to thrive in urban environments by mimicking human food choices.
“Gulls didn’t evolve to like chips. Over time they have had to learn to engage with humans in order to source food. It is therefore a sign of intelligence.
“But gulls may be less likely to steal our food if we focus on reducing litter. That’s because littering increases gulls’ ability to learn about how our different food options and how they taste.”