Butterfly Conservation has access to a massive amount of data about butterflies. It is vital. It tells us what species are in decline and where to find them.
This information is gathered by volunteers. We'd like your help too.
Recording can take as much or as little time as you like. You can do it anywhere you see a butterfly that you can identify, whether in your garden or at the top of a mountain.
Butterfly Conservation's general recording scheme is known as Butterflies for the New Millennium or BNM.
It covers all species of butterflies across the UK and is run in conjunction with the national Biological Records Centre (part of the Centre for Ecology & Hydrology).
BNM was launched when it became clear that butterfly distributions had changed substantially since the previous national survey in the 1970s.
From 1995 to 1999, Britain and Ireland were completely resurveyed. More than 10,000 volunteers and hundreds of organisations participated, contributing over 1.6 million butterfly sightings. The resulting data formed the basis of a major book - The Millennium Atlas of Butterflies in Britain and Ireland.
The BNM has continued since then, undertaking back-to-back five-year surveys of butterfly distributions across the UK and amassing over 12 million sightings. Historical records (dating back to the 17th Century) have been added too and, as a result, we can assess long-term changes in the distributions of all our butterfly species.
The results so far
Many species have declined at alarming rates over recent decades. Others are spreading northwards into new areas, probably because of global warming. Since the 1970s, three-quarters of butterfly species have declined in distribution in Britain and over one third are listed as threatened on the Red List of British Butterflies. The records gathered through the BNM scheme form a key component of the regular State of the UK's Butterflies reports.
Continued recording is essential in order to gauge the extent of these changes. Despite, the immense volunteer effort many areas are still under-recorded. You can help by sending your butterfly sightings to your local BNM Co-ordinator. They will check the sightings and compile them into a local database, before forwarding your observations onto the national BNM recording scheme.
The BNM database is a powerful tool for research, for example into the effect of global warming, and has been used in many scientific papers (see recent publications).
Butterflies are good indicators of environmental change and the quality of our countryside and urban landscape. They are easy to record and identify and can be used as a barometer of many thousands of other, less well known insects.
Come and join us
BNM is vital to the conservation of butterflies and to raising awareness of their plight. It also enables many people to play an active part in the conservation effort. If you want to come and join us, contact your local Butterfly Conservation Branch or BNM Co-ordinator, or find more information on how to get started here.