A report for ministers from civil servants suggests that the vendor who sells seed for them in the square might have his licence withdrawn. Alternatively, anti-pigeon wire and spikes could be placed on surrounding roosting places; this has already been tried elsewhere in London.
''But ministers might judge we don't need to do anything about the pigeons,'' said a spokeswoman for the department. ''After all, they are part of the square's attraction for many visitors, and the fact that seed is sold there means the birds are in better condition than in some other places.''
The report considers the possibility of using a trained hawk to frighten them off, and of shooting and poisoning them. But it points out that the public might be unhappy about a major cull, and that it would be impossible to eliminate pigeons entirely from the square.
Meanwhile the London Evening Standard, in a public-spirited gesture, has had ten pigeon corpses analysed by a laboratory in Norwich which found they harboured a rich variety of disease-causing organisms, including those which cause food poisoning, thrush and skin lesions. The laboratory also looked at the contents of the birds' digestive tracts. There they found the remains of Chinese takeaway food, bread and a small piece of plastic yellow carton from the McDonald's hamburger chain.