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LESSER WHITETHROAT Sylvia curruca
 
Conservation Listings Long term trend

Unlisted/Green
Biodiversity Steering Group
Conservation Concern List

UK: Fluctuating with no long-term trend
Scrub (CES): Moderate decline
 
Status Summary
Lesser Whitethroat abundance tended to be stable (albeit with short-term fluctuations) from the 1960s until the late 1980s, but there is evidence for a moderate decline from then on in the CBC, CES and BBS trends. These changes were significant and large enough over the relevant period to trigger BTO Alerts from all three schemes. The causes of the decline warrant conservation concern and research action. Productivity on CES plots has declined recently.
 
 
Table of population change for Lesser Whitethroat
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 30 1968-1998 55 -13 -40 26    
  25 1973-1998 59 -20 -41 9    
  10 1988-1998 54 -31 -44 -18 >25  
  5 1993-1998 51 -10 -23 3    
CBC farmland 30 1968-1998 31 10 . .    
  25 1973-1998 32 -13 . .    
  10 1988-1998 33 -12 . .    
  5 1993-1998 31 8 . .    
CES adults 14 1984-1998 44 -44 . . [>25*]  
  10 1988-1998 51 -53 . . [>50*]  
  5 1993-1998 52 -45 . . [>25*]  
CES juveniles 14 1984-1998 45 -37 . . [>25*]  
  10 1988-1998 52 -54 . . [>50*]  
  5 1993-1998 54 -59 . . [>50*]  
BBS UK 5 1994-1999 195 -31 -42 -17 (>25)  
BBS England 5 1994-1999 186 -31 -43 -17 (>25)  
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information for Lesser Whitethroat
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Percentage juveniles (CES) 14 1984-1998 57 Smoothed trend 98 productivity index 100 productivity index 2%  
Percentage juveniles (CES) 10 1988-1998 66 Smoothed trend 113 productivity index 100 productivity index -11%  
Percentage juveniles (CES) 5 1993-1998 69 Smoothed trend 148 productivity index 100 productivity index -33%[>25]  
 

 

Insufficient data on clutch size
available for this species

 

 

Insufficient data on brood size
available for this species

 

 

Insufficient data on nest failure
available for this species

 

 

Insufficient data on nestling failure available for this species

 

Insufficient data on laying date
available for this species
   




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Last updated: 15 March, 2001

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