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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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DUNNOCK Prunella modularis
 
Conservation Listings Long term trend

Table 4/Amber
(25-49% Population decline)

Biodiversity Steering Group Conservation Concern List

UK: Moderate decline
Woodland: Rapid decline
 
Status Summary
Dunnock abundance crashed between the mid-1970s and mid-1980s, after a period of population stability. Since the mid-1980s, no recovery has occurred but the CBC, CES and BBS all show abundance to have been stable. The cause of the decline remains unknown. There has been little variation in survival over time (Siriwardena et al. 1998) and breeding performance tends to have increased.
 
 
Table of population changes for Dunnock
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 30 1968-1998 205 -46 -54 -37 >25  
  25 1973-1998 210 -46 -54 -38 >25  
  10 1988-1998 188 -7 -15 2    
  5 1993-1998 193 -2 -8 4    
CBC farmland 30 1968-1998 93 -44 -53 -33 >25  
  25 1973-1998 92 -45 -55 -34 >25  
  10 1988-1998 91 -1 -12 9    
  5 1993-1998 92 2 -5 10    
CBC woodland 30 1968-1998 71 -58 -66 -47 >50  
  25 1973-1998 75 -56 -65 -46 >50  
  10 1988-1998 74 -17 -27 -7    
  5 1993-1998 78 -9 -14 -2    
CES adults 14 1984-1998 91 -13 . .    
  10 1988-1998 104 -10 . .    
  5 1993-1998 113 -1 . .    
CES juveniles 14 1984-1998 88 -15 . .    
  10 1988-1998 101 -10 . .    
  5 1993-1998 111 -10 . .    
BBS UK 5 1994-1999 1414 7 2 13    
BBS England 5 1994-1999 1169 5 0 10    
BBS Scotland 5 1994-1999 97 9 -15 38    
BBS Wales 5 1994-1999 102 16 -4 39    
BBS N.Ireland 5 1994-1999 37 174 58 372   Small sample
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information for Dunnock
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 30 1968-1998 104 Linear increase 3.91 eggs 4.18 eggs 0.27 eggs  
Brood size 30 1968-1998 110 Linear increase 3.42 chicks 3.67 chicks 0.25 chicks  
Daily failure rate (eggs) 30 1968-1998 146 Curvilinear 0.0269 nests/day 0.026 nests/day -0.0009 nests/day  
Daily failure rate (chicks) 30 1968-1998 116 None        
Laying date 30 1968-1998 83 None        
Percentage juveniles (CES) 14 1984-1998 95 Smoothed trend 99 productivity index 100 productivity index 1%  
Percentage juveniles (CES) 10 1988-1998 109 Smoothed trend 102 productivity index 100 productivity index -2%  
Percentage juveniles (CES) 5 1993-1998 117 Smoothed trend 106 productivity index 100 productivity index -6%  
 
   




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Last updated: 15 March, 2001

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