Map explanation

This map shows where changes occurred in the relative abundance of the species in Wiltshire between 1995-2000 and 2007-2012, as revealed by the fieldwork for Birds of Wiltshire (Wiltshire Ornithological Society 2007) and the shared fieldwork for Bird Atlas 2007-2011 (BTO 2013) and for Wiltshire Tetrad Atlas 2007-2012.


Relative to average

Nos tetrads

More abundant



Equally abundant



Less abundant



Not surveyed in both periods

Grasshopper Warblers breed across Eurasia from northernmost Spain, France, the north Balkans and the Caucasus, north to Ireland, Britain and southern Fenno-Scandia and thence eastwards across Russia to Siberia and Mongolia. They winter in sub-Saharan Africa,
    In Great Britain they are widely distributed, being absent only from Shetland, the Outer Hebrides and upland areas in mainland Scotland and northern England. Their numbers are however thinning out as much of their preferred habitat (young conifer plantations, rough grassland, downland scrub, damp and boggy areas) has been cleared or drained. Bird Atlas 2007-2011 recorded a reduction of 11% in the number of occupied 10km squares in Britain since the 1968-72 Breeding Atlas, most of the decrease occurring in south, central and northeast England, partly offset by increases in Wales, southeast Scotland and, especially, in Ireland.
    In Wiltshire in the 19th century they were described as widespread but in small numbers. In the mid 20th century they were said to be regular but uncommon, nesting in some river valleys and young plantations. Birds of Wiltshire recorded them in 90 tetrads, with breeding probable or confirmed in 33 of them. WTA2 recorded them in 74 tetrads with breeding in 24. Both atlases showed that nesting was mainly confined to Salisbury Plain, with smaller clusters in the valleys of the rivers Ray and Kennet. An RSPB survey carried out on Salisbury Plain in 2000 estimated a total of 264 Grasshopper Warbler territories there, roughly 2.5% of the total British population, though a later recalculation reckoned that this figure was too high and that the total Wiltshire population was between 150 and 275  pairs.

The following references are used throughout these species’ accounts, in the abbreviated form given in quotation marks:
1968-72 Breeding Atlas” – Sharrack, J.T.R. 1976:  The Atlas of Breeding Birds in Britain and Ireland. T. & A. Poyser
1981-84 Winter Atlas” – Lack, P.C. 1986:  The Atlas of Wintering Birds in Britain and Ireland. T. & A. Poyser
1988-91 Breeding Atlas” – Gibbons, D.W., Reid, J.B. & Chapman, R.A. 1993: The New Atlas of Breeding Birds in Britain and Ireland 1988-91. T. & A. Poyser
Birds of Wiltshire” – Ferguson-Lees, I.J. et al. 2007: Birds of Wiltshire, published by the tetrad atlas group of the Wiltshire Ornithological Society after mapping fieldwork 1995-2000. Wiltshire Ornithological Society.
Bird Atlas 2007-2011”-– Balmer, D.E., Gillings, S., Caffrey, B.J., Swann, R.L., Downie, I.S. and Fuller, R.J. 2013: The Breeding and Wintering Birds of Britain and Ireland. BTO Books. 
WTA2” – ("Wiltshire Tetrad Atlas 2 ") the present electronic publication, bringing together the Wiltshire data from “Birds of Wiltshire” and “Bird Atlas 2007-11”, together with data from further fieldwork carried out in 2011 and 2012.
"Hobby" - the annual bird report of the Wiltshire Ornithological Society.