This article suggests that the number of sparrows in Britain has fallen by as much as 68% in the past three decades. The decline has been put down to the fact that many people pave over their gardens and remove trees causing a decline in the the insects that the birds eat. The article suggests that sparrows have disappeared from cities such as London, Bristol and Edinburgh. The problem is that many chicks are starving to death in the nest because they are not getting enough food to become strong enough to fly. Chick survival was found to be higher in areas where there were more insects such as aphids. There are things you can do to encourage sparrows such as growing honeysuckle, wild roses, hawthorn and fruit trees and leaving some untidy areas in your garden to encourage more insects. I have noticed that we don't have a lot of sparrows in our area, but they do seem to like the berries in our hedge and this time of year we tend to have a small community that take advantage of the seasonal food. After reading this article I don't think I will trim the hedge until the birds have had chance to take full advantage of all the berries, it might look a little untidy but I'm sure the sparrows will appreciate the extra food this winter.