Category A, B, C species
Species in Categories A, B and C form the British List
Species in Category A have been recorded in an apparently natural state at least once since 1 January 1950.
Species in Category B have been recorded in an apparently natural state at least once between 1 January 1800 and 31 December 1949, but have not been recorded subsequently.
Species in Category C, although introduced, now derive from the resulting self-sustaining populations. View Category C sub-categories
The BOU is responsible for maintaining the British List. Part of this responsibility is to monitor the occurrence of non-native species which may qualify for addition to Category C of the British List. To undertake this we require published information from which to work and which we can quote as reference.
The BOU uses two forms of English names for the British List:
- vernacular English names in popular use by British birders
- the IOC’s standard international English name as per Gill, F & D Donsker (Eds). 2011. IOC World Bird Names (version 2.10). Available at www.worldbirdnames.org [accessed 23/12/11]
Taxonomy used for the List is as per the IOC World Bird List View Taxonomy