The British Trust for Ornithology
TREE SPARROW
Passer montanus
Tree Sparrow © Tommy Holden
Conservation listings

Table 3/Red (>=50% Population decline)
Biodiversity Steering Group Priority Species List

Long-term trend
UK: Rapid decline
 
Status summary
Tree Sparrow abundance crashed between the late 1970s and the mid-1980s; abundance was comparatively stable beforehand and has remained so subsequently, as BBS data confirm. Clear range contractions have also occurred (Gibbons et al. 1993). Breeding performance has improved as population sizes have decreased, suggesting that decreases in productivity are not responsible for the decline. Failure rates at the egg stage (16 days, comprising 12 days incubation + 4 days laying), for example, fell from 11% to 6%. It is likely that survival may have been more critical demographic rate, although ring-recovery analyses have produced equivocal results because of small sample sizes (Siriwardena et al. 1998b, 2000b). Features of agricultural intensification, such as reductions in winter stubble availability are likely to be implicated in the decline.
 
 
Table of population changes for Tree Sparrow
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 31 1968-1999 59 -96 -98 -91 >50  
  25 1974-1999 52 -95 -98 -90 >50  
  10 1989-1999 20 -53 -78 -21 >50 Small sample
  5 1994-1999 14 -21 -50 7   Small sample
CBC farmland 31 1968-1999 39 -93 -98 -86 >50  
  25 1974-1999 34 -93 -97 -86 >50  
  10 1989-1999 16 -56 -81 -23 >50 Small sample
  5 1994-1999 11 -22 -59 8   Small sample
BBS UK 6 1994-2000 134 25 2 54    
BBS England 6 1994-2000 114 3 -18 28    
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information for Tree Sparrow
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 31 1968-1999 93 Linear increase 4.78 eggs 5.35 eggs 0.57 eggs  
Brood size 31 1968-1999 104 Linear increase 3.84 chicks 4.51 chicks 0.67 chicks  
Daily failure rate (eggs) 31 1968-1999 122 Curvilinear 0.0072 nests/day 0.0037 nests/day -0.0035 nests/day  
Daily failure rate (chicks) 31 1968-1999 87 None        
Laying date 31 1968-1999 106 None        
 
Insufficient data on CES
available for this species
 




Wider Countryside Home | BTO Home | JNCC Home

This report should be cited as:
Baillie, S.R., Crick, H.Q.P., Balmer, D.E., Beaven, L.P., Downie, I.S., Freeman, S.N., Leech, D.I., Marchant, J.H.,
Noble, D.G., Raven, M.J., Simpkin, A.P., Thewlis, R.M. and Wernham, C.V.
(2002) Breeding Birds in the Wider
Countryside: their conservation status 2001. BTO Research Report No. 278. BTO, Thetford. (http://www.bto.org/birdtrends)

Terms and Conditions of use
Privacy Statement


© British Trust for Ornithology
BTO, The Nunnery, Thetford, Norfolk IP24 2PU, UK. Registered Charity Number 216652
Tel: +44 (0)1842 750050 Fax: +44 (0)1842 750030 Email:

This page last updated: 21 April, 2008

Page created by Susan Waghorn