Siriwardena, G.M. et al

Bird counts from the Glastir Monitoring and Evaluation Programme, Wales 2013-2016

The data set consists of bird species counts, recorded in 300 1km squares across Wales, collected as part of the Glastir Monitoring and Evaluation Programme (GMEP). The monitoring programme was set up by the Welsh Government in 2013 to monitor the effects of the Glastir agri-environment scheme on the environment and ran from 2013 to 2016.
The field survey element was based on a stratified random sampling design of 300 x 1km square sites across Wales, and was managed by the UK Centre for Ecology & Hydrology.

Publication date: 2020-06-04

Get the data

This dataset is available under the terms of the Open Government Licence

Format of the data: Comma-separated values (CSV)

You must cite: Siriwardena, G.M.; Taylor, R.M.; Norfolk, D.; Jones, K.; Alison, J.; Astbury, S.; Burden, A.; Emmett, B.A.; Garbutt, A. ; Henrys, P.; Owen, A.; Smart, S.M.; Sharps, K.; Williams, B.; Wood, C.M. (2020). Bird counts from the Glastir Monitoring and Evaluation Programme, Wales 2013-2016. NERC Environmental Information Data Centre.


All use of the data (or any part of it) must be accompanied by an acknowledgement of the source in the following format:

© Crown copyright: Welsh Government licenced under the Open Government Licence v3.0

© Hawlfraint y Goron: Llywodraeth Cymru Mae’r holl gynnwys ar gael dan Drwydded Llywodraeth Agored v3.0

For the avoidance of doubt, if the publication of the Licensed Data is not within Wales, the Welsh form of the acknowledgement wording is not required.


Study area
Temporal extent
2013-03-04    to    2016-06-30

Provenance & quality

The surveys consisted of four (reduced to three from 2015-16 onwards) visits to each square by trained, professional surveyors using standardised protocols. Surveys were equally spaced through mid-March to mid-July. On each visit, the surveyor walked a route that passed within 50m of all parts of the survey square to which access had been secured, beginning at around 06:00 and taking up to five hours. Surveys were not conducted in conditions known to affect the detection of birds, i.e. strong winds and more than light rain. The survey route was started in different places on each visit, so that all areas were visited at least once before 08:00. All birds seen or heard were recorded on high-resolution field maps using standard BTO activity codes. Recording and standardizing route coverage (where surveyors actually walked) was important both between visits and to ensure comparable repeat coverage when squares are revisited.
Data were recorded on standard forms and field maps, which were collated in the British Trust for Ornithology (BTO) Wales office in Bangor and sent to the BTO head office for digital inputting, after being copied physically and electronically in Bangor. Data were then digitized using ArcMap (versions up to v10.5). The process included checking of uncertain counts, species codes and identifications, for which the digitizer checked the data with the surveyor if necessary, before making a judgement on likely record accuracy. Additional checks were intrinsic to subsequent data processing before being loaded into a final database at UK CEH.
To ensure confidentiality of the data with respect to land owners and managers, the locations of 1km squares and survey sites were converted to the centres of the containing 10km Ordnance Survey grid squares.


This dataset is included in the following collections

Glastir Monitoring and Evaluation Programme, Wales, 2013-2016

Supplemental information

Glastir Monitoring and Evaluation Programme (GMEP) website
Website for related survey - Environment & Rural Affairs Monitoring and Modelling Programme (ERAMMP)
Website for related national survey - Countryside Survey

Correspondence/contact details

Alison, J.
UK Centre for Ecology & Hydrology
Lancaster Environment Centre, Library Avenue, Bailrigg


Siriwardena, G.M.
British Trust for Ornithology
Taylor, R.M.
British Trust for Ornithology
Norfolk, D.
British Trust for Ornithology
Jones, K.
British Trust for Ornithology
Alison, J.
UK Centre for Ecology & Hydrology
Astbury, S.
UK Centre for Ecology & Hydrology
Burden, A.
UK Centre for Ecology & Hydrology
Emmett, B.A.
UK Centre for Ecology & Hydrology
Garbutt, A.
UK Centre for Ecology & Hydrology
Henrys, P.
UK Centre for Ecology & Hydrology
Owen, A.
UK Centre for Ecology & Hydrology
Smart, S.M.
UK Centre for Ecology & Hydrology
Sharps, K.
UK Centre for Ecology & Hydrology
Williams, B.
UK Centre for Ecology & Hydrology
Wood, C.M.
UK Centre for Ecology & Hydrology

Other contacts

NERC EDS Environmental Information Data Centre
NERC Environmental Information Data Centre

Additional metadata

Topic categories
agri-environment scheme,  Biodiversity birds,  Environmental survey Glastir Monitoring and Evaluation Programme,  GMEP,  Wales
Environmental Monitoring Facilities
Welsh Government
Spatial representation type
Tabular (text)
Spatial reference system
OSGB 1936 / British National Grid
Last updated
10 November 2021 12:44