Contents of report
Breeding Bird Survey
Common Birds Census
Constant Effort Sites
Nest Record Scheme
Waterways Bird Survey
What the categories mean
Return to BTO Home Page
Conservation Listings Long term trend

Table 4/Amber
(25-49% Distribution decline)

Biodiversity Steering Group
Concern List

UK: Probable decline
Status Summary
Grasshopper Warbler was Amber-listed because of a contraction in range up to the 1988-1991 Atlas, reportedly due to habitat loss (Gibbons et al. 1993). CBC analysis cannot be conducted reliably because of a small sample size but a rapid population decline is believed to have occurred. The BBS shows fluctuations in abundance but no net change. If given suitable habitat and conditions, the species has a high reproductive potential, demonstrated by a detailed analysis of the NRS dataset (Glue 1990).
Table of population changes for Grasshopper Warbler
Source Period
Years Plots
Alert Comment
BBS UK 5 1994-1999 59 -3 -34 41    
BBS England 5 1994-1999 26 -2 -44 73   Small sample
The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB
No productivity information available for this species



The report should be cited as: Baillie, S.R., Crick, H.Q.P., Balmer, D.E., Bashford, R.I., Beaven, L.P., Freeman, S.N., Marchant, J.H., Noble, D.G., Raven, M.J., Siriwardena, G.M., Thewlis, R. and Wernham, C.V. (2001) Breeding Birds in the Wider Countryside: their conservation status 2000. BTO Research Report No. 252. BTO, Thetford. (

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