Contents of report
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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SAND MARTIN Riparia riparia
 
Conservation Listings Long term trend

Table 4/Amber (European status)
Biodiversity Steering Group
Conservation Concern List

UK: Fluctuating with no long-term trend
 
Status Summary
New analytical techniques now allow long-term population trends to be produced for Sand Martin for the first time. The WBS shows a stable population with some fluctuations, but movements of whole colonies may cause problems with the survey and may have obscured the true long-term trends. Winter rainfall in the species' sub-Saharan wintering grounds are believed to affect annual survival and thus abundance in the following breeding season.
 
 
Table of population changes for Sand Martin
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
WBS waterways 23 1975-1998 18 70 -11 276   Small sample
  10 1988-1998 24 -11 -35 57    
  5 1993-1998 26 16 -11 55    
BBS UK 5 1994-1999 92 15 -11 48    
BBS England 5 1994-1999 61 17 -14 60    
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information for Sand Martin
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Brood size 30 1968-1998 12 None       Small sample
 
Insufficient data on clutch 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 dates
available for this species

 

 

Insufficient data on CES
available for this species

 

   




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Last updated: 15 March, 2001

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