Saturday, July 25

Why gulls live on our chimney pots

The Clean Air Acts of 1956 and 1968 allowed London boroughs to establish smoke control zones. Almost overnight it became an offence within such areas to burn fuel which generated “dark smoke” – and yes – the law clearly defines a shade of grey that constitutes dark smoke. These Acts all but banned the use of traditional domestic fireplaces burning wood and coal. As a result, most domestic fireplaces have become purely ornamental or a home for inherently smokeless gas and electric heating systems.

These laws were introduced in response to the heavy, unhealthy smogs that once made headlines. The worse of them all was The Great Smog of 1952. A five-day period in early December of that year saw London smothered by a thick yellow-grey cloud, much of it generated by dirty domestic coal fires. Visibility across the city was reduced to a few yards making driving difficult or impossible. Public transport ground to a halt. The smog even seeped indoors, causing concerts and movie screening to be cancelled.

The Great Smog also demonstrated a powerful, but deadly, relationship between pollution and public health. As sulphur dioxide and smoke particles peaked (up to seven times higher than normal), so did the number of deaths. By the time the air cleared, at least 4000 premature deaths had been attributed to the Great Smog. More recent research suggests that correct figure may have been closer to 12,000.

The Clean Air Acts have proved incredibly effective. London’s air is remarkably clear for a city of seven million people. The city’s many dormant chimney pots have also become popular nesting spots. Our own home at Swiss Cottage hosts an annual gull nest atop our main chimney stack. This week we spotted the first of this year’s brood attempting to fly the nest.

As happened last year, the young gull became stranded on a window sill part way down our building where it remains for several days. We last saw it striding around the neighbour’s yard on Thursday evening. It was gone by Friday. I wonder if our local fox had a tasty meal overnight?

UPDATE - July 27
Sunday evening we saw an young gull on the neighbour's roof ridge. Shortly after we also saw our fox run by with a large garbage bag in his mouth. It would seem that our baby gull has survived its flying lessons and our fox isn't going hungry.

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