Official Statistics: Point of first release for statistics on abundance of UK butterflies (2018 publication; includes data up to 2017)
Trends of UK butterfly species are based on results of the UK Butterfly Monitoring Scheme (UKBMS), presented at UK level, and at country level where there are sufficient data. The UKBMS helps the UK to meet its obligations under the European Habitats Directive (for Marsh Fritillary and Large Blue), and to report on, implement or deliver country biodiversity strategies and biodiversity indicators.
The UK Butterfly Monitoring Scheme is organized and funded by Butterfly Conservation, the Centre for Ecology and Hydrology, British Trust for Ornithology, and the Joint Nature Conservation Committee. The UKBMS is indebted to all volunteers who contribute data to the scheme.