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MAGPIE Pica pica
 
Conservation Listings Long term trend

Unlisted/Green
Biodiversity Steering Group: Unlisted

UK: Rapid increase, now stable
 
Status Summary
Magpies increased steadily until the late 1980s, when abundance stabilised, a stabilisation apparent in both CBC and BBS indices (Gregory & Marchant 1996). The trend has been associated with increases in breeding performance and earlier laying, as with other corvids, and probably reflects the benefits of a generalist strategy under changing environmental conditions. The decline in nest failure rates has been substantial, for the egg stage (21 days, comprising 17 days incubation + 4 days laying) failure rates have fallen from 45% to 9%, and for the chick stage (25 days) failure rates fell from 36% to 5%. Overall, from egg laying to fledging, the proportion of nests failing has fallen from 65% to 14%, and is likely to be the result of reductions in gamekeeping activity. The trend in laying date can be partially explained by recent climate change (Crick & Sparks 1999). This adaptability has allowed a spread into urban and suburban habitats. Reduced control activities by gamekeepers may also have helped Magpies (Marchant et al. 1990).
 
 
Table of population changes for Magpie
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 30 1968-1998 157 107 74 154    
  25 1973-1998 167 83 61 114    
  10 1988-1998 161 1 -8 7    
  5 1993-1998 162 -1 -6 4    
CBC farmland 30 1968-1998 71 67 . .    
  25 1973-1998 74 57 . .    
  10 1988-1998 77 -1 . .    
  5 1993-1998 75 2 . .    
CBC woodland 30 1968-1998 56 186 . .    
  25 1973-1998 63 102 . .    
  10 1988-1998 68 0 . .    
  5 1993-1998 70 -3 . .    
BBS UK 5 1994-1999 1335 4 0 9    
BBS England 5 1994-1999 1131 1 -3 7    
BBS Scotland 5 1994-1999 31 19 -16 69   Small sample
BBS Wales 5 1994-1999 116 16 -1 36    
BBS N.Ireland 5 1994-1999 49 9 -16 43   Small sample
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information for Magpie
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 30 1968-1998 52 Curvilinear 5.55 eggs 4.91 eggs -0.64 eggs  
Brood size 30 1968-1998 88 Curvilinear 3.19 chicks 3.77 chicks 0.58 chicks  
Daily failure rate (eggs) 30 1968-1998 59 Linear decline 0.0278 nests/day 0.0047 nests/day -0.0231 nests/day  
Daily failure rate (chicks) 30 1968-1998 57 Linear decline 0.0177 nests/day 0.0021 nests/day -0.0156 nests/day  
Laying date 30 1968-1998 40 Curvilinear day 110 day 88 -22 days  
 
Insufficient data on CES
available for this species
   



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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