Contents of report
Breeding Bird Survey
Common Birds Census
Constant Effort Sites
Nest Record Scheme
Waterways Bird Survey
Alerts
Summary
What the categories mean
Return to BTO Home Page
.
WOOD WARBLER Phylloscopus sibilatrix
 
Conservation Listings Long term trend

Unlisted/Green
Biodiversity Steering Group Conservation Concern List

UK: Unknown
 
Status Summary
Wood Warblers have a western-biased distribution in Britain and were not monitored well before the inception of the BBS. Little change in range occurred between the two breeding atlas projects (Gibbons et al. 1993) and little change is apparent on the few CBC plots on which the species occurs (Crick et al. 1998). There have also been no significant trends in breeding performance. The BBS shows a significant decline since 1994 that should be monitored carefully to assess the need for conservation action.
 
 
Table of population changes for Wood Warbler
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
BBS UK 5 1994-1999 58 -45 -60 -24 (>25)  
BBS England 5 1994-1999 27 -63 -77 -42 (>50) Small sample
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 30 1968-1998 18 None       Small sample
Brood size 30 1968-1998 39 None        
Daily failure rate (eggs) 30 1968-1998 23 None       Small sample
Daily failure rate (chicks) 30 1968-1998 28 None       Small sample
Laying date 30 1968-1998 34 None        
 
Insufficient data on CES
available for this species
   




[ Welcome | Contents | Introduction | CBC | WBS | BBS | Heronries | CES | NRS | Alerts ]
[ Summary | Discussion | References | Help | BTO Home Page ]

© 2000 British Trust for Ornithology
BTO, The Nunnery, Thetford, Norfolk IP24 2PU
Tel: (+44) (0) 1842 750050 Fax: (+44) (0) 1842 750030 Email: info@bto.org

Last updated: 15 March, 2001

Page created by Susan Waghorn