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Breeding Bird Survey
Common Birds Census
Constant Effort Sites
Nest Record Scheme
Waterways Bird Survey
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Summary
What the categories mean
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CHIFFCHAFF Phylloscopus collybita
 
Conservation Listings Long term trend

Unlisted/Green
Biodiversity Steering Group
Conservation Concern List

UK: Fluctuating with no long-term trend
 
Status Summary
Chiffchaff abundance crashed in the late 1960s/early 1970s in common with that of other trans-Saharan warblers (Siriwardena et al. 1998), subsequently remaining stable for a decade before recovering strongly from the mid-1980s onwards. This recovery can be seen in the CBC and CES. Climate change can partially explain the trend towards earlier laying (Crick & Sparks 1999). However, over-winter survival may be the critical driver of changes in abundance as it is for Whitethroat and Sedge Warbler.
 
 
Table of population changes in Chiffchaff
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 30 1968-1998 131 14 -9 46    
  25 1973-1998 135 52 25 88    
  10 1988-1998 151 43 28 61    
  5 1993-1998 163 25 17 35    
CBC farmland 30 1968-1998 43 49 . .    
  25 1973-1998 42 86 . .    
  10 1988-1998 51 64 . .    
  5 1993-1998 54 44 . .    
CBC woodland 30 1968-1998 66 -12 . .    
  25 1973-1998 71 22 . .    
  10 1988-1998 83 24 . .    
  5 1993-1998 90 16 . .    
CES adults 14 1984-1998 62 92 . .    
  10 1988-1998 72 25 . .    
  5 1993-1998 81 26 . .    
CES juveniles 14 1984-1998 73 115 . .    
  10 1988-1998 85 15 . .    
  5 1993-1998 97 37 . .    
BBS UK 5 1994-1999 882 -7 -13 -1    
BBS England 5 1994-1999 753 -7 -13 -1    
BBS Wales 5 1994-1999 86 -15 -31 4    
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information for Chiffchaff
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 30 1968-1998 27 None       Small sample
Brood size 30 1968-1998 30 None       Small sample
Daily failure rate (eggs) 30 1968-1998 34 None        
Daily failure rate (chicks) 30 1968-1998 30 None       Small sample
Laying date 30 1968-1998 40 Curvilinear day 135 day 123 -12 days  
Percentage juveniles (CES) 14 1984-1998 81 Smoothed trend 94 productivity index 100 productivity index 6%  
Percentage juveniles (CES) 10 1988-1998 95 Smoothed trend 118 productivity index 100 productivity index -15%  
Percentage juveniles (CES) 5 1993-1998 105 Smoothed trend 96 productivity index 100 productivity index 4%  
 
   




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Last updated: 15 March, 2001

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