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CHAFFINCH Fringilla coelebs
 
Conservation Listings Long term trend

Unlisted/Green
Biodiversity Steering Group: Unlisted

UK: Shallow increase
 
Status Summary
Chaffinch abundance increased rapidly during the 1970s and 1980s, but numbers seem to have stabilised since 1990 since a similar pattern is shown by each of the CBC, CES and BBS indices. The stabilisation has been associated with a reduction in annual survival, which could be a density-dependent effect (Siriwardena et al. 1999). There is also some evidence of improvements in breeding performance during the population increase (declines in egg-stage nest failure rates and increased brood sizes). Trends in laying date can be partially explained by recent climate change (Crick & Sparks 1999). Chaffinches are well-adapted to suburban and garden habitats, as well as highly fragmented woodland and hedgerows, so may have benefitted from the environmental changes from which other seed-eating passerines have suffered. They are also less dependent upon the open-field, cropped habitats that have been affected most by agricultural intensification.
 
 
Table of population changes for Chaffinch
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 30 1968-1998 216 21 9 36    
  25 1973-1998 223 23 13 34    
  10 1988-1998 212 -1 -5 4    
  5 1993-1998 220 1 -3 4    
CBC farmland 30 1968-1998 94 27 . .    
  25 1973-1998 94 25 . .    
  10 1988-1998 94 3 . .    
  5 1993-1998 95 3 . .    
CBC woodland 30 1968-1998 85 3 . .    
  25 1973-1998 90 13 . .    
  10 1988-1998 97 -5 . .    
  5 1993-1998 102 -1 . .    
CES adults 14 1984-1998 76 20 . .    
  10 1988-1998 86 10 . .    
  5 1993-1998 95 -5 . .    
CES juveniles 14 1984-1998 54 52 . .    
  10 1988-1998 63 15 . .    
  5 1993-1998 71 -6 . .    
BBS UK 5 1994-1999 1730 3 0 6    
BBS England 5 1994-1999 1342 3 0 6    
BBS Scotland 5 1994-1999 192 1 -8 11    
BBS Wales 5 1994-1999 134 -14 -23 -3    
BBS N.Ireland 5 1994-1999 53 64 20 123    
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 

 
Table of productivity information for Chaffinch
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 30 1968-1998 89 None        
Brood size 30 1968-1998 143 Linear increase 3.61 chicks 3.8 chicks 0.19 chicks  
Daily failure rate (eggs) 30 1968-1998 170 Curvilinear 0.0307 nests/day 0.0362 nests/day 0.0055 nests/day  
Daily failure rate (chicks) 30 1968-1998 118 None        
Laying date 30 1968-1998 115 Curvilinear day 129 day 121 -8 days  
Percentage juveniles (CES) 14 1984-1998 80 Smoothed trend 106 productivity index 100 productivity index -6%  
Percentage juveniles (CES) 10 1988-1998 92 Smoothed trend 112 productivity index 100 productivity index -11%  
Percentage juveniles (CES) 5 1993-1998 101 Smoothed trend 104 productivity index 100 productivity index -4%  
 
   


The report should be cited as: Baillie, S.R., Crick, H.Q.P., Balmer, D.E., Bashford, R.I., Beaven, L.P., Freeman, S.N., Marchant, J.H., Noble, D.G., Raven, M.J., Siriwardena, G.M., Thewlis, R. and Wernham, C.V. (2001) Breeding Birds in the Wider Countryside: their conservation status 2000. BTO Research Report No. 252. BTO, Thetford. (http://www.bto.org/birdtrends)




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