Most of the houses of East Sheen in south-west London were built on farmland as part of the great explosion of suburbia between the 1890s and 1930s. The houses are solid and the rear gardens long. There are ancient copses in nearby Richmond Park and the surrounding patches of common land but most of the garden trees were planted by the first residents and have grown over the years to maturity, just as the hedges of hawthorn and privet have grown taller and thicker. Patient gardening turns the soil and throws up worms and hundreds of other varieties of insect. A consequence of all this activity is that, with the destruction of wild woodland and the poisoning of farmland by chemical fertilizers, perhaps the safest place for wild birds is now a leafy suburb – apart, that is, from the large number of cats, sitting with deadly patience under hedges and in long grass, but I’ll come back to them.