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BTO Blueline
CARRION CROW
Corvus corone
Carrion Crow © Mike Weston
 
Conservation listings
Europe (C. corone/cornix): no SPEC category (favourable conservation status in Europe, not concentrated in Europe)
UK (C. corone/cornix): Green
Long-term trend 
England: rapid increase
Distribution maps
Maps and statistics from British and Irish
atlases can be viewed here.
Status summary
Carrion Crows have increased steadily since the 1960s (Gregory & Marchant 1996) and both the CBC and the BBS indicate that the increase is continuing. This trend has been associated with increases in nesting success and earlier laying (perhaps an effect of climate change: Crick et al. 1997) and probably reflects the species' adaptability to changing habitats and the exploitation of ephemeral food resources in intensive agriculture. Reduced control activities by gamekeepers may also have contributed (Marchant et al. 1990), as may an increase in roadside carrion.
 
CBC/BBS UK graph
 
Table of population changes for Carrion Crow
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC/BBS England 35 1967-2002 458 110 76 168    
  25 1977-2002 596 55 37 88    
  10 1992-2002 1257 19 12 27    
  5 1997-2002 1659 7 3 14    
BBS UK 9 1994-2003 1734 8 3 14    
BBS England 9 1994-2003 1416 18 12 25    
BBS Scotland 9 1994-2003 149 -15 -29 3    
BBS Wales 9 1994-2003 161 -1 -15 14    
BBS acknowledgement
 
BBS UK graph
BBS England graph
BBS Scotland graph
BBS Wales graph
 
Table of productivity changes for Carrion Crow
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 34 1968-2002 36 None        
Brood size 34 1968-2002 82 Curvilinear 2.86 chicks 2.61 chicks -0.25 chicks  
Daily failure rate (eggs) 34 1968-2002 54 Linear decline 0.0158 nests/day 0.0028 nests/day -0.013 nests/day  
Daily failure rate (chicks) 34 1968-2002 45 Linear decline 0.0068 nests/day 0.0021 nests/day -0.0047 nests/day  
Laying date 34 1968-2002 34 Curvilinear day 106 day 97 -9 days  
 
Clutch size graph
Brood size graph
Egg nest failure graph
Chick nest failure graph
Laying date graph
Insufficient data on CES
available for this species
 
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This report should be cited as:
Baillie, S.R., Marchant, J.H., Crick, H.Q.P., Noble, D.G., Balmer, D.E., Beaven, L.P., Coombes, R.H.,
Downie, I.S., Freeman, S.N., Joys, A.C., Leech, D.I., Raven, M.J., Robinson, R.A. and Thewlis, R.M. (2005)
Breeding Birds in the Wider Countryside: their conservation status 2004.
BTO Research Report No. 385. BTO, Thetford. (http://www.bto.org/birdtrends)

Pages maintained by Susan Waghorn and Iain Downie: Last updated 18 January, 2006