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The UK Butterfly Monitoring Scheme (UKBMS)

In the UK Butterfly Monitoring Scheme (UKBMS), annual data on the population status of butterflies is derived from a wide-scale program of site-based monitoring and sampling in randomly selected 1km squares. The sampling framework comprises: (1) Weekly butterfly transects (Pollard walks); (2) Reduced effort surveys of habitat specialist species (including timed counts of adults, single species transects, and egg and larval counts); and (3) the Wider Countryside Butterfly Survey (WCBS). The resulting UKBMS dataset is one of the most important resources for understanding changes in insect populations and answering policy questions relating to status and trends in biodiversity... [more]

The scheme has monitored changes in the abundance of butterflies throughout the United Kingdom since 1976. Forty years later, trends in butterfly populations were compiled from a network of over 4,000 locations across all years, with nearly 2,500 sample locations monitored in 2015.

The UKBMS is based on a well-established and enjoyable recording method listed above and has produced important insights into almost all aspects of butterfly ecology.

A new publication, "The State of Butterflies in Britain and Ireland", was launched on May 15th. This book is a follow-up to the hugely successful Butterflies for the New Millenium atlas, and is available to purchase from the publishers, Nature Bureau (price: £14.50 inc. p&p)


The UK Butterfly Monitoring Scheme is organized and funded by Butterfly Conservation (BC), the Centre for Ecology and Hydrology (CEH), the British Trust for Ornithology (BTO), and the Joint Nature Conservation Committee (JNCC). The UKBMS is indebted to all volunteers who contribute data to the scheme.