Wider Countryside Butterfly Survey

Small Tortoiseshell by Josie Latus

The Wider Countryside Butterfly Survey (WCBS) is the main scheme for monitoring population changes of the UK's common and widespread butterflies. It is important in both assessing the changing status of widespread butterfly species and in providing an indicator of the health of the wider countryside. Data from this scheme feeds into the UK Butterfly Monitoring Scheme (UKBMS).

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 and we now have data from the WCBS, carried out on BBS squares spanning back to the pilot years of 2007 and 2008.

All BBS volunteers can take part in the WCBS by making extra visits to their square between May and August to count butterflies.

If you would like to get involved, all you need to get started is tell us at bbs [at] bto.org so we can allocated your BBS square for the WCBS and then either download the


instructions (PDF, 260.74 KB)

recording form

recording form (PDF, 95.12 KB)
or email bbs [at] bto.org to request a paper pack of forms. Square allocation for the WCBS on BBS squares and all WCBS data from BBS squares are entered into the UKBMS data entry system. For guidance on how to register your BBS square for the WCBS on the UKBMS website, please email bbs [at] bto.org.

Entering data for the WCBS

WCBS online simple instructions for WCBS-BBS squares:

1. Register at www.ukbms.org/mydata/ (register button is at top right hand side of the screen). When choosing your username on this website, it is helpful to us if you use your BTO username.

2. Wait for us to email you to confirm that your account has been linked to your square(s). This can only be done during working hours, so please be patient.

3. Once allocated the square, log in to the UKBMS website. Go to ‘My Sites’ to review the details of your route, change Location Type to WCBS-BBS in the drop down menu then press Run Report.

4. Go to ‘My Walks’ to enter the data from your weekly walks. First change the Site Type to WCBS-BBS in the drop down menu then find the date of your walk in the calendar and click on the little green ‘plus’ sign. You can now enter details of your survey.

Latest results

The latest results of the UK Butterfly Monitoring Scheme (UKBMS), updated with the data from 2019, are now available. Butterfly numbers can fluctuate markedly between years in response to weather conditions. 2019’s unusually warm and wet summer proved particularly conducive to the successful development of the immature stages preceding a strong emergence of adults. Marbled White, which had its best year in the 44-year series of monitoring data, saw its annual abundance up by 66% on the previous year; Ringlet was up by 23%, Dark Green Fritillary by 51%, and Meadow Brown by 38%. 2019 was also a very good year for two of our migrant butterflies, with Red Admiral annual abundance up by 195% (the fifth best year in the series for this species) and Painted Lady was up by a massive 1,993% (the third best year in the series).

It wasn’t all good news for butterflies though, as the Common Blue dropped in annual abundance by 54% (compared with 2018), Adonis Blue by 40%, Green-veined White by 43% and Large White by 40% – all four species had below average years. Of particular concern is the rare Heath Fritillary, restricted to a tiny number of sites in southern England. This butterfly saw its annual abundance drop by 34%, an ongoing decline that raises fears for its long-term future.

The annual changes in the abundance of 57 different butterfly species since the 1970s presented here are based on analyses of the counts undertaken every year by thousands of volunteers that participate in the scheme. In addition to counts made by Breeding Bird Survey participants and Butterfly Conservation volunteers for the Wider Countryside Butterfly Survey, these trends use information from traditional weekly butterfly transects as well as timed counts for some species.


The latest publications using WCBS data can be viewed on the BBS related reports and newsletters webpage. This includes the WCBS newsletters and the UKBMS Annual Report.

WCBS Partners

British Trust for Ornithology logo
Butterfly Conservation logo
UK Centre for Ecology & Hydrology logo
JNCC logo

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