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TREE PIPIT Anthus trivialis
 
Conservation Listings Long term trend

Unlisted/Green
Biodiversity Steering Group Conservation Concern List

UK: Unknown
Lowland England: Rapid decline

 
Status Summary
Tree Pipits occur in greatest abundance in Wales, north England and Scotland, and thus the marked CBC decline may reflect the range contraction that has occurred in central and south-east England (Gibbons et al. 1993). This is confirmed by the contrasting patterns of change shown by the BBS in Scotland and England. While populations have increased in Scotland, there has been a substantial decline in England over the past 5 years, corroborating the decline shown by the CBC over the same time period. Improvements have occurred in breeding performance with a substantial increase in brood size and a decline in failure rates over the 17 day egg stage (13 days incubation + 4 days laying) from 55% to 17%. The causes of the population decline are unclear, but may be linked to changing forest structure (with maturity) and increased grazing pressure in woodland (Vanhinsbergh et al. 2001).
 
 
Table of population changes for Tree Pipit
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 30 1968-1998 33 -77 -88 -65 >50 Unrepresentative
  25 1973-1998 32 -77 -87 -64 >50 Unrepresentative
  10 1988-1998 21 -68 -81 -54 >50 Unrepresentative
  5 1993-1998 20 -31 -53 -13 >25 Unrepresentative, small sample
BBS UK 5 1994-1999 119 21 -1 48    
BBS England 5 1994-1999 64 -26 -43 -3 (>25)  
BBS Scotland 5 1994-1999 27 86 19 190   Small sample
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
 
 
Table of productivity information for Tree Pipit
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Brood size 30 1968-1998 29 Linear increase 4.33 chicks 4.74 chicks 0.41 chicks Small sample
Daily failure rate (eggs) 30 1968-1998 12 Linear decline 0.0453 nests/day 0.0104 nests/day -0.0349 nests/day Small sample
Daily failure rate (chicks) 30 1968-1998 18 None       Small sample
Laying date 30 1968-1998 17 Curvilinear day 145 day 132 -13 days Small sample
 
Insufficient data on CES
available for this species
   




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Last updated: 15 March, 2001

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