BMS schemes

Butterfly Monitoring Schemes

Butterfly Monitoring Schemes (BMS) record butterflies every year, by counting them along fixed routes called transects. This vital information is gathered mainly by citizen scientists (volunteers) who have been trained (or are self-taught) to recognise and identify species and follow the protocols of monitoring along butterfly transects.

Butterflies are one of the best-monitored insect groups in Europe thanks to the long-term monitoring schemes that have been running for decades in some countries. The first Butterfly Monitoring Scheme began in the United Kingdom in 1976 (UKBMS), since then, this methodology has been adopted in many other European countries to monitor butterflies. All use the same standardised survey method, designed by Ernie Pollard, of the Monks Wood Experimental Station in the UK (Pollard and Yates, 1983). The transects (fixed routes) are counted repeatedly through the butterfly season, ideally every week but often less frequently due to the availability of volunteers or due to unsuitable weather. Statistical modeling techniques have been developed to account for uneven sampling and enable standardized assessments of changes in abundance over time. The methodology provides robust data to identify population trends and assess the status of butterfly species.


The eBMS network includes several partners that provide their data every year from the different National Butterfly Monitoring Schemes throughout Europe. Currently, there are 23 partners in 20 different countries with their respective BMS. Click on the countries to see their National BMS websites and discover more about their butterfly monitoring, how to join and contact them.


Austria - AUBMS

Austria (Viel-Falter) - VFBMS

Belgium (Flanders) - BEBMS

Croatia - HRBMS

Czech Republic - CZBMS

Finland - FIBMS

France - FRBMS

Germany - DEBMS

Hungary - HUBMS

Ireland - IRBMS

Italy - ITBMS website

Luxembourg - LUBMS

Lithuania - LTBMS

Norway -  NOBMS

Portugal - PTBMS

Slovenia - SIBMS

Spain (Catalonia) - ES-CTBMS

Spain (Zerynthia) - ES-CBBMS

Spain (excl. Catalonia, Zerynthia) - ESBMS

Sweden - SEBMS

Switzerland - CHBMS

The Netherlands  - NLBMS



The map on the right shows the spatial distribution of transects across major biogeographic regions in Europe from the eBMS database (2020 update map with data until 2019). Graphs: a) Number of transect per year between 1990-2018 in the eBMS database b) Number of schemes in every year (clear colors refer to countries outside EU) between 1990 - 2018.




If you want to set up a new transect in one of these countries, please follow the links in each country and try to contact the main coordinator. Some countries have their own online system to manage national Butterfly Monitoring Schemes. 

For requesting data from the eBMS database, please go to the page eBMS data access policy to read and see how to do this process.