There are several ongoing studies seeking reasons for the decline in the house sparrow population over the past thirty years.

Once common everywhere it is largely absent in most former locations now. Many theories have been put forward. One suggests the increasing use of unleaded petrol possibly affecting insects. Certainly there are fewer insects around including butterflies and moths clearly demonstrated round my porch light where thirty years ago moths were abundant in late evening but now I rarely see one.

Perhaps there is less natural food available for sparrow nestlings at a crucial period in their development.

However, I have always maintained that the main reason for our cockney sparrers decline is lack of suitable nesting sites.

Traditionally nesting under the eaves of houses and other buildings access is now frequently denied because loft spaces and entry points are sealed to increase insulation.

Not only does this situation apply to sparrows but starlings and swifts, also declining species find fewer nesting opportunities.

I know of some small but thriving house sparrow colonies all of which congregate around older style properties that still offer scope for entry under the gutters.

Old fashioned privet hedges, a common sight around front gardens years ago have largely disappeared as low walls are demolished to allow more car parking spaces so the birds are also deprived of shelter.