ae7542e2-bf37-4391-b47e-96ed3f6fe096 English ISO/IEC 8859-1 (also known as Latin 1) dataset dataset NERC EDS Environmental Information Data Centre Lancaster Environment Centre, Library Avenue, Bailrigg Lancaster LA1 4AP UK info@eidc.ac.uk https://eidc.ac.uk/ EIDC website The Environmental Information Data Centre (EIDC) is the UK's national data centre for terrestrial and freshwater sciences. information pointOfContact 2026-01-09T10:10:35 UK GEMINI 2.3 OSGB 1936 / British National Grid United Kingdom Butterfly Monitoring Scheme: species trends 2023 2025-02-11 publication https://catalogue.ceh.ac.uk/id/ae7542e2-bf37-4391-b47e-96ed3f6fe096 10.5285/ae7542e2-bf37-4391-b47e-96ed3f6fe096 doi: Botham, M.S., Middlebrook, I., Heywood, J., Harrower, C., Conway, R., Roy, D.B. (2025). United Kingdom Butterfly Monitoring Scheme: species trends 2023. NERC EDS Environmental Information Data Centre 10.5285/ae7542e2-bf37-4391-b47e-96ed3f6fe096 This dataset provides linear trends, over varying time periods, for the Collated Indices of individual butterfly species across the UK. The main statistical values derived from a linear regression (slope, standard error, P-value) are presented for the entire time series for each species (1976# to 2023), for the last 20 years, and for the last decade. In addition, trends are classified based on the direction and significance of a linear slope together with an estimated percentage change for that time period. These trend data are provided for all UK butterfly species for which we have sufficient data (58 species). Trends are calculated by performing a linear regression on the annual Collated indices for each species. Collated indices are calculated using a log-linear model incorporating individual site indices from all monitored sites across the UK for a given species in a given year. Trends across different time series allow us to determine the long and short-term status of individual species. This is enables us to focus conservation and research and also to assess species responses to conservation already in place. The UK Butterfly Monitoring Scheme is organized and funded by Butterfly Conservation (BC), the UK Centre for Ecology & Hydrology (UKCEH), 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. This work was supported by the Natural Environment Research Council award number NE/R016429/1 as part of the UK-SCAPE programme delivering National Capability. #Because the Collated indices are only calculated for each species in years in which it was recorded on five or more sites, the starting year for the series is later than 1976 for a number of rarer species. Full details about this dataset can be found at https://doi.org/10.5285/ae7542e2-bf37-4391-b47e-96ed3f6fe096 Botham, M.S. UK Centre for Ecology & Hydrology enquiries@ceh.ac.uk https://orcid.org/0000-0002-5276-1405 ORCID record ORCID is an open, non-profit, community-driven effort to create and maintain a registry of unique researcher identifiers and a transparent method of linking research activities and outputs to these identifiers. information author Middlebrook, I. Butterfly Conservation imiddlebrook@butterfly-conservation.org https://orcid.org/0000-0002-0448-9144 ORCID record ORCID is an open, non-profit, community-driven effort to create and maintain a registry of unique researcher identifiers and a transparent method of linking research activities and outputs to these identifiers. information author Heywood, J. British Trust for Ornithology james.heywood@bto.org author Harrower, C. UK Centre for Ecology & Hydrology enquiries@ceh.ac.uk https://orcid.org/0000-0001-5070-5293 ORCID record ORCID is an open, non-profit, community-driven effort to create and maintain a registry of unique researcher identifiers and a transparent method of linking research activities and outputs to these identifiers. information author Conway, R. Butterfly Conservation rconway@butterfly-conservation.org author Roy, D.B. UK Centre for Ecology & Hydrology enquiries@ceh.ac.uk https://orcid.org/0000-0002-5147-0331 ORCID record ORCID is an open, non-profit, community-driven effort to create and maintain a registry of unique researcher identifiers and a transparent method of linking research activities and outputs to these identifiers. information author Botham, M. UK Centre for Ecology & Hydrology enquiries@ceh.ac.uk pointOfContact NERC EDS Environmental Information Data Centre info@eidc.ac.uk custodian NERC EDS Environmental Information Data Centre info@eidc.ac.uk publisher UK Centre for Ecology & Hydrology enquiries@ceh.ac.uk owner Butterfly Conservation EMAIL NOT PROVIDED owner British Trust for Ornithology EMAIL NOT PROVIDED owner Natural Environment Research Council EMAIL NOT PROVIDED owner Joint Nature Conservation Committee EMAIL NOT PROVIDED owner Environmental Monitoring Facilities theme GEMET - INSPIRE themes, version 1.0 2008-06-01 publication lepidopteran GEMET - Concepts, version 4.1.3 2019-01-28 creation Biodiversity Environmental survey annual butterflies England Northern Ireland Scotland United Kingdom Wales UK-SCAPE otherRestrictions no limitations otherRestrictions This resource is available under the terms of the Open Government Licence otherRestrictions Contains UK Butterfly Monitoring Scheme (UKBMS) data © copyright and database right Butterfly Conservation, the UK Centre for Ecology & Hydrology, British Trust for Ornithology, and the Joint Nature Conservation Committee. otherRestrictions If you reuse this data, you should cite: Botham, M.S., Middlebrook, I., Heywood, J., Harrower, C., Conway, R., Roy, D.B. (2025). United Kingdom Butterfly Monitoring Scheme: species trends 2023. NERC EDS Environmental Information Data Centre https://doi.org/10.5285/ae7542e2-bf37-4391-b47e-96ed3f6fe096 textTable English utf8 environment 2023-01-01 2023-12-31 -8.648 1.768 49.864 60.861 Comma-separated values (CSV) NERC EDS Environmental Information Data Centre info@eidc.ac.uk distributor https://data-package.ceh.ac.uk/data/ae7542e2-bf37-4391-b47e-96ed3f6fe096 Download the data Download a copy of this data download https://data-package.ceh.ac.uk/sd/ae7542e2-bf37-4391-b47e-96ed3f6fe096.zip Supporting information Supporting information available to assist in re-use of this dataset information dataset dataset Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 Trends are calculated by performing a linear regression on the annual Collated Indices for each species. Indices are calculated for all species (across Wider Countryside Butterfly Survey squares and traditional UKBMS sites) using the Generalised Abundance Index (GAI) method developed in 2016 with an additional modification that the data from each site in each year is weighted in the final stage relative to the proportion of the species flight period surveyed that year for that site. They give a statistical measure of how the abundance of each species has changed on monitored sites since 1976, over the last 20 years, and over the last decade. Because the Collated indices are only calculated for each species in years in which there was sufficient data available, the starting year for the series is later than 1976 for a number of rarer species