The causes of the decline of the urban House Sparrow population in Britain

By Kate E. Vincent, Ph.D.
In Britain and parts of northwest Europe, House Sparrow Passer domesticus populations have declined markedly since the mid-1980s. This study focused on factors affecting nesting success and annual productivity of nesting House Sparrows along an urban-suburban-rural gradient centred on the city of Leicester, England. The data presented in this thesis suggest that the abundance of invertebrate prey within home ranges of House Sparrows breeding within suburban and rural habitats limits the quantity and quality of chicks raised to fledging. The combined effects of relatively high rates of chick starvation and low body masses at fledging (and consequently low post-fledging survival) observed in surburban localities are large enough to result in rapid population declines.

Kate E. Vincent (2005). Investigating the causes of the decline of the urban House Sparrow Passer domesticus population in Britain. De Montfort University, Ph.D. Thesis.
http://www.katevincent.org/thesis/HouseSparrows%20(final%20version).pdf

Insect crash at root of House Sparrow decline:
http://www.farmlandbirds.net/en/node/21