Asked by: Liam Johnson, Plymouth
No. They have always been very aggressive, particularly when defending nesting sites. What they are becoming is more numerous. In the wild, herring gulls might only raise one chick to maturity for every 10 breeding pairs per year. The rest are lost to predation from other seabirds, birds of prey and seals. In contrast, gulls that nest in cities have more secure nests and much greater access to food, mostly from rubbish bins and landfill sites. Street lighting also allows birds to forage at night.
For example, Bristol now has more than 2,000 breeding pairs of gulls, each of which can raise two or three chicks a year. The increased population density means that humans are much more likely to encroach on nesting territory. Seagulls will actively defecate and vomit on anyone they perceive as a threat, before resorting to dive bombing.
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