Contents of report
Breeding Bird Survey
Common Birds Census
Constant Effort Sites
Nest Record Scheme
Waterways Bird Survey
What the categories mean
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MERLIN Falco columbarius
Conservation Listings Long term trend

Table 2/Red (Historical decline)
Biodiversity Steering Group
Conservation Concern List

UK: Probable increase

Status Summary
Having declined substantially over the past two centuries, there are indications that it has increased recently (DETR 2000), perhaps associated with an increased use of forest edge as a nesting habitat (Parr 1994). Breeding performance has tended to improve since the 1960s, probably linked to the declining influence of organochlorine pesticides (Crick 1993).
Annual breeding population changes for this species
are not currently monitored by BTO
Table of productivity information for Merlin
Variable Period
Years Mean
Trend Predicted
in first year
in last year
Change Comment
Clutch size 30 1968-1998 40 None        
Brood size 30 1968-1998 56 Linear increase 3.44 chicks 3.79 chicks 0.35 chicks  
Daily failure rate (eggs) 30 1968-1998 29 None       Small sample
Daily failure rate (chicks) 30 1968-1998 29 None       Small sample


Insufficient data on laying date
available for this species



Insufficient data on CES
available for this species



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Last updated: 7 March, 2001

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