They are the scourge of the seaside, the bandits of the beachfront. Now scientists have gleaned an insight into why seagulls are drawn to stealing holidaymakers’ chips: they actively prefer food that has been handled by humans.
Researchers from Exeter University’s Penryn campus in Cornwall presented herring gulls in several Cornish towns with two identical flapjacks, one of which the gulls had seen in a person’s hand. Of the 38 gulls that were tested, 24 pecked at one of the flapjacks and 19 of these — nearly 80 per cent — chose the one that had been handled.
The birds are kleptoparasites, which means they pilfer food from other animals. The strategy has allowed them to adapt to new environments, including seaside tourist hotspots.
“UK herring gull numbers are declining, but urban populations have increased,” Madeleine Goumas, of the Centre for Ecology and Conservation at Penryn campus, who led the latest study, said.
Despite increasing interactions between humans and gulls, little is known about the cognitive underpinnings of urban gull behaviour, she added. “We wanted to find out if gulls are simply attracted by the sight of food, or if people’s actions can draw their attention.”
Laura Kelly, a co-author of the study published today in the Royal Society Open Science, said the findings highlighted the need to dispose of food waste properly.
The same researchers reported last year that fixing a seagull with a hard stare was often effective in scaring them off. The UK population of herring gulls fell by 60 per cent from 1969 to 2015, putting the birds on the red list of Birds of Conservation Concern. Nevertheless, a YouGov poll in 2016 found that 44 per cent of people backed a cull.
For the Exeter study, a researcher approached individual gulls and placed two buckets on the ground in front of them, each covering a wrapped flapjack taped to a piece of slate to stop the gulls making off with it.
The buckets were then removed, and the researcher picked up one of the flapjacks, handled it for 20 seconds, and then placed it back on the ground.
To see if gulls were responding to human handling alone, the experiment was repeated with two non-food items, sponges cut to be the same size and shape as the flapjacks. The gulls showed no extra interest in the handled sponge. This suggests, the researchers said, that handling draws their attention to food in particular.
From The Times Science Correspondent
Owl notes the research was conducted on Cornish Herring Gulls but thinks their Devon cousins behave the same way.