This dataset includes information on site visits carried out as part of the UK Ruddy Duck Eradication Programme which began in September 2005. It includes details of all visits, some of which were made with the purpose of culling Ruddy Ducks, while some were made with the sole intention of counting the numbers of Ruddy Ducks present on the site. Please note: for columns W to Y, data refers to an assessment made in the field. More accurate checks were made at a later date in the laboratory - see columns AD to AI. Column AA (Number of Wounded Ducks left on site) is an estimate of the maximum number of birds thought to have been wounded but not dispatched before leaving the site. Codes for other species present are those used by the British Trust for Ornithology and others. Attribution statement: ©Crown Copyright, APHA 2016