Changes to Category C of the British List

2 November 2005 | Marek Walford

You've probably heard that the BOU have undertaken a review of category C species and published a paper. It's a long document (11,349 words) so to save you the trouble of reading it thoroughly I've extracted the relevant information with regards to the Berkshire List. Category C has been split into six sub-categories but for the sake of simplicity I'll refer to them as a whole. In summary the changes are:

Species Old category New category
Snow GooseA,EA,C,E
Greater Canada GooseA,C,EC,E
Barnacle GooseA,EA,C,E
Muscovy DuckERefer to JNCC
Red-crested PochardA,EA,C,E
Feral PigeonA,EA,C,E

Effect on the Berkshire List

Category E species (escaped birds) are generally considered not tickable while category C species (feral birds) are generally considered tickable. So, Berkshire listers will be most interested in those species that have been added to category C.

Snow Goose

The only population listed in the report as being self-sustaining, and therefore tickable is in Argyll. The paper says the following about Hampshire:

An increasing number of birds has been encountered in the county with 29 present in 1996, including five breeding pairs (no young seen) at Eversley. Numbers declined to 13 in 2003 with one or two pairs attempting to breed annually at Stratfield Saye (young seen in 1999 and 2000), including a mixed pair with Greylag Goose (Hampshire Ornithological Society, Ogilvie & RBBP 2002, 2003). This declining and localized population is not considered to be self-sustaining, although continued monitoring is recommended as this could change.

Barnacle Goose

The only populations listed in the report as being self-sustaining, and therefore tickable are in Bedfordshire and Norfolk/Suffolk. The paper says the following about Hampshire:

Hampshire: population between 190 and 270 individuals with breeding regularly confirmed, including up to 24 pairs fledged 42 young at Stratfield Staye (1998) with eight pairs (20 fledged young) in 2002 (Hampshire Bird Report 1997-2003).

Red-crested Pochard

Red-crested Pochard was in categories A and E. Category E birds are not tickable but category A birds are. Most Berks birders have been ticking RCP for years. If you search your sole you know that the bird you ticked at Theale didn't come from continental Europe, but from the Cotswold Water Park in Wiltshire. Luckily, you need not feel dirty or ashamed any more as the Wiltshire population is now considered to be self-sustaining.


Berks birders may feel a little robbed of a tick when it comes to Barnacle Goose but there is some hope. Buried deep in the paper is the following sentence.

The BOU will not act as arbiters or assessors of other local populations once a species has been admitted to The British List, but will periodically review published data by the RBBP, county and regional bird reports and other publications to monitor that specific species continue to satisfy their Category C status.

This suggests that the BOU considers county record committees, with access to up-to-date information to be in the best position to judge whether a population is self-sustaining. So it appears that whether or not we can tick Barnacle Goose is in the hands of the Berks Records Committee.