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LITTLE OWL Athene noctua
 
Conservation Listings Long term trend

Unlisted/Green
Biodiversity Steering Group: Unlisted

UK: Uncertain
 
Status Summary
The CBC trend for Little Owl shows fluctuations but no clear trend over the long-term, as does the BBS for the late 1990s. However, these trends may not be very reliable because the species is crepuscular or nocturnal and therefore not ideally suited to standard survey methods. A population estimate of c. 7,000 pairs from the BTO/Hawk and Owl Trust's Project Barn Owl (Toms et al. 2000) is the first replicable and reliable estimate for the UK. Although annual sample sizes are small, there are no trends evident in breeding performance for the species.
 
 
Table of population changes for Little Owl
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 30 1968-1998 29 -29 -56 12    
  25 1973-1998 30 -8 -44 39    
  10 1988-1998 28 -22 -45 6    
  5 1993-1998 28 -4 -26 20    
BBS UK 5 1994-1999 84 -8 -31 23    
BBS England 5 1994-1999 81 -5 -29 29    
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information for Little Owl
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 30 1968-1998 13 None       Small sample
Brood size 30 1968-1998 31 None        
Daily failure rate (eggs) 30 1968-1998 12 None       Small sample
Daily failure rate (chicks) 30 1968-1998 17 None       Small sample
 

 

Insufficient data on laying dates
available for this species

 

 

Insufficient data on CES
available for this species

 

   




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Last updated: 14 March, 2001

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