Contents of report
Breeding Bird Survey
Common Birds Census
Constant Effort Sites
Nest Record Scheme
Waterways Bird Survey
Alerts
Summary
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GREY WAGTAIL Motacilla cinerea
 
Conservation Listings Long term trend

Unlisted/Green
Biodiversity Steering Group
Conservation Concern List

UK: Uncertain
Linear Waterways: Rapid decline
 
Status Summary
Grey Wagtail populations are densest in northern and western Britain, where the CBC and WBS do not provide representative coverage, but the WBS will cover the species' habitat very well. The trends shown by both surveys are very similar to those for Pied Wagtail, notably featuring a rapid decline through the 1970s, but subsequently remaining stable. The similarity in the trends suggests that they have similar causes. Grey Wagtail breeding performance has improved markedly over time, suggesting that it cannot be the demographic rate responsible for the decline or for holding the population constant subsequently. (The change in the 12-day nestling stage failure rates is from 16% to 9%.)
 
 
Table of population changes for Grey Wagtail
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 30 1968-1998 18 45 -21 388   Unrepresentative? small sample
  25 1973-1998 19 -24 -49 42   Unrepresentative? small sample
  10 1988-1998 20 8 -23 49   Unrepresentative? small sample
  5 1993-1998 20 2 -20 23   Unrepresentative? small sample
WBS waterways 23 1975-1998 57 -48 -61 -30 >25  
  10 1988-1998 65 -18 -33 -2    
  5 1993-1998 67 -7 -18 4    
BBS UK 5 1994-1999 138 40 14 73    
BBS England 5 1994-1999 86 24 -5 61    
BBS Scotland 5 1994-1999 24 107 24 246   Small sample
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information for Grey Wagtail
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 30 1968-1998 43 Linear increase 4.8 eggs 5.01 eggs 0.21 eggs  
Brood size 30 1968-1998 88 Linear increase 4.06 chicks 4.5 chicks 0.44 chicks  
Daily failure rate (eggs) 30 1968-1998 65 None        
Daily failure rate (chicks) 30 1968-1998 63 Curvilinear 0.0146 nests/day 0.0081 nests/day -0.0065 nests/day  
Laying date 30 1968-1998 68 None        
 
Insufficient data on CES
available for this species
   




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Last updated: 15 March, 2001

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