Since the 1940s, some herring and lesser black-backed gulls have used rooftops for nesting. It's not known exactly what prompted this move, but abundant inland sources of food and safe, predator-free nesting sites on rooftops were definite factors.

The 1956 Clean Air Act prevented rubbish tip operators burning waste, so gulls took advantage of the huge amount of organic material increasingly generated by our 'throw-away' society and sent to landfill. Many urban streets are also frequently replete with discarded food and accessible rubbish and some people feed gulls.

The birds nesting on roofs of houses are most likely to be herring gulls, whilst lesser black-backed gulls tend to concentrate on the larger expanses of industrial or commercial buildings with flat roofs. Although numbers of roof-nesting gulls, especially lesser black-backed gulls, are still increasing, the overall population of herring gulls is plummeting, making them a red list species. The lesser black-backed gull population has also declined in recent years.

Government licences allow the killing of urban gulls only as a last resort, where a significant risk to public health or safety has been identified. While we understand that roof-nesting gulls can cause problems, we question the appropriateness of lethal control on a declining, red-listed species and highlight the need to comply with European bird protection law.

Furthermore, it is extremely difficult to distinguish between the nests, eggs or downy chicks of herring and lesser black-backed gull - even fledged young look identical to all but an expert eye. This makes species-specific control measures difficult.