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.
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.
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