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Breeding Bird Survey
Common Birds Census
Constant Effort Sites
Nest Record Scheme
Waterways Bird Survey
Alerts
Summary
What the categories mean
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GREAT TIT Parus major
 
Conservation Listings Long term trend

Unlisted/Green
Biodiversity Steering Group Conservation Concern List

UK: Moderate increase
 
Status Summary
Great Tits have increased since the 1960s with two brief periods of stability or shallow decline breaking up the steady upward trajectory. The BBS suggests that the increase is continuing, especially in England. A positive effect of increasing winter food provision by humans is one possible explanation for the increase. Changes in different aspects of breeding performance are contradictory but CES productivity shows a shallow decline, which may be related to high population levels (density-dependent competition).
 
 
Table of population changes for Great Tit
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 30 1968-1998 210 50 34 69    
  25 1973-1998 217 28 15 41    
  10 1988-1998 208 10 5 16    
  5 1993-1998 215 7 4 11    
CBC farmland 30 1968-1998 89 61 . .    
  25 1973-1998 89 27 . .    
  10 1988-1998 90 14 . .    
  5 1993-1998 89 12 . .    
CBC woodland 30 1968-1998 85 27 . .    
  25 1973-1998 90 21 . .    
  10 1988-1998 96 5 . .    
  5 1993-1998 102 3 . .    
CES adults 14 1984-1998 86 10 . .    
  10 1988-1998 98 19 . .    
  5 1993-1998 107 15 . .    
CES juveniles 14 1984-1998 87 0 . .    
  10 1988-1998 100 5 . .    
  5 1993-1998 110 -8 . .    
BBS UK 5 1994-1999 1460 12 7 18    
BBS England 5 1994-1999 1201 9 3 14    
BBS Scotland 5 1994-1999 102 31 4 64    
BBS Wales 5 1994-1999 112 21 1 44    
BBS N.Ireland 5 1994-1999 36 60 2 153   Small sample
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information for Great Tit
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 30 1968-1998 95 None        
Brood size 30 1968-1998 163 Linear decline 7.36 chicks 6.75 chicks -0.61 chicks  
Daily failure rate (eggs) 30 1968-1998 156 Linear decline 0.0062 nests/day 0.0037 nests/day -0.0025 nests/day  
Daily failure rate (chicks) 30 1968-1998 129 None        
Laying date 30 1968-1998 118 None        
Percentage juveniles (CES) 14 1984-1998 94 Smoothed trend 119 productivity index 100 productivity index -16%  
Percentage juveniles (CES) 10 1988-1998 107 Smoothed trend 120 productivity index 100 productivity index -16%  
Percentage juveniles (CES) 5 1993-1998 117 Smoothed trend 121 productivity index 100 productivity index -17%  
 

 

   



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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