Investigating the causes of the decline of the urban house sparrow Passer domesticus population in Britain
type: CreativeWork
description: In Britain and parts of northwest Europe, House Sparrow Passer domesticus populations have declined markedly in urban-suburban landscapes since the mid-1980s. Little is known about the demographic mechanisms or environmental causes of these population declines, although lack of winter seed has been implicated as a cause of the decline in House Sparrow numbers on English farmland (Hole, 2001). 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. Chick diet (inferred from faecal remains), habitat selection by foraging adults and over-winter survival were also studied. Data were collected during 2001-2003 from 9 study areas spread along the urbanisation gradient. Most sparrows in most study areas nested in or close to domestic gardens. Counts of territorial males declined by 28% between 2001 and 2003, with the largest declines in rural villages (25%) and suburban fringe (16%) and a small increase (4%) in the urban centre. Annual productivity (the estimated number of fledged young/pair/year) was 25% lower in suburban areas and 18% lower in rural areas than that measured during a recent study of farmland House Sparrows in Oxfordshire. The main cause of this lower productivity was starvation of chicks, (usually the first 5-6 days after hatching) during June and July. Chicks were more likely to starve if their diet contained a high proportion of vegetable material (mainly supplementary food) or ants, and less likely to starve if their diet contained a high proportion of spiders. The number of young sparrows successfully fledging, and the aggregate chick biomass, per nesting attempt were greater in home ranges containing relatively high proportions of deciduous shrub, trees and grass, and relatively little concrete. During June and July 2003, more young fledged from home ranges containing a higher density of aphids. Dipteran prey (Tipulids a…
abstract: In Britain and parts of northwest Europe, House Sparrow Passer domesticus populations have declined markedly in urban-suburban landscapes since the mid-1980s. Little is known about the demographic mechanisms or environmental causes of these population declines, although lack of winter seed has been implicated as a cause of the decline in House Sparrow numbers on English farmland (Hole, 2001). 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. Chick diet (inferred from faecal remains), habitat selection by foraging adults and over-winter survival were also studied. Data were collected during 2001-2003 from 9 study areas spread along the urbanisation gradient. Most sparrows in most study areas nested in or close to domestic gardens. Counts of territorial males declined by 28% between 2001 and 2003, with the largest declines in rural villages (25%) and suburban fringe (16%) and a small increase (4%) in the urban centre. Annual productivity (the estimated number of fledged young/pair/year) was 25% lower in suburban areas and 18% lower in rural areas than that measured during a recent study of farmland House Sparrows in Oxfordshire. The main cause of this lower productivity was starvation of chicks, (usually the first 5-6 days after hatching) during June and July. Chicks were more likely to starve if their diet contained a high proportion of vegetable material (mainly supplementary food) or ants, and less likely to starve if their diet contained a high proportion of spiders. The number of young sparrows successfully fledging, and the aggregate chick biomass, per nesting attempt were greater in home ranges containing relatively high proportions of deciduous shrub, trees and grass, and relatively little concrete. During June and July 2003, more young fledged from home ranges containing a higher density of aphids. Dipteran prey (Tipulids a…
author: Vincent, Kate E.
license: https://dora.dmu.ac.uk/bitstreams/74854e22-94b7-4726-8236-06e084e8ad17/download
date published: 2005
date modified: 2026-07-24T06:18:40Z
provider: De Montfort University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: De Montfort University