Butterfly distribution records for the UK from Butterfly Conservation, up to 2019

Butterfly Conservation

Description

UK butterfly distribution data from the Butterflies for the New Millennium (BNM) recording scheme, run by Butterfly Conservation. This dataset comprises occurrence records of butterfly species collected by volunteers, professionals and the public. The data include records of all resident butterfly species plus natural migrants, but exclude adventive species. Records were made from a wide range of terrestrial habitats and throughout the year and were collated from multiple source datasets or surveys. All records were checked by local taxonomic expert volunteers (County Recorders) prior to inclusion. Records are presented at 2km x 2km (tetrad) grid square resolution (unless deemed to be sensitive records).

For more information about butterflies, recording and the UK recording scheme please visit https://butterfly-conservation.org/butterflies. This dataset includes derived information from the UK Butterfly Monitoring Scheme, which is organised and funded by Butterfly Conservation, the UK Centre for Ecology and & Hydrology, British Trust for Ornithology, and the Joint Nature Conservation Committee. Information about UKBMS and its Open Government Licence data is available from https://ukbms.org/

Geographic Description

This dataset represents almost complete coverage of 10km x 10km grid squares in the United Kingdom, the Isle of Man and the Channel Islands. Location is given as the dominant Vice County for each record in Great Britain; for Northern Ireland a nominated Vice County is selected where more than one overlap the grid square.

Purpose

Multiple datasets have been collated to create the BNM database from which this dataset is derived. Data are collected for different original purposes including personal interest or site monitoring. Contribution to the BNM dataset is for the purpose of maintaining a UK-wide understanding of the distribution of butterflies, and how this has changed over time, to inform science, conservation and education.

The purpose of this dataset is to inform public understanding, biodiversity conservation and scientific research regarding the current and past distribution of butterfly species at landscape, county, regional and national scales in the UK. For local or site-level decisions, finer scale BNM records are more appropriate and access to such data and appropriate interpretive advice should be sought from local environmental records centres or Butterfly Conservation.

Data quality

We have a high degree of confidence in the dataset overall and believe that all reasonable steps have been taken to ensure that records are correct and complete. Verification of records is undertaken by expert volunteers at the local (county) level and subsequent checks are also made on the UK dataset. Records are accepted from untrained amateurs, as well as skilled volunteers and professionals, but UK butterflies are a relatively easy group of organisms to identify (compared with almost any other invertebrate taxa). This fact, together with the verification provided by local experts (as described above) gives good grounds for confidence in veracity of the dataset. Apparent errors in the data should be reported to the administrator for further investigation. The records have not been systematically checked using NBN Record Cleaner but local verifiers are encouraged to use this tool as part of their process.

Methods

The primary source of data is as direct field observations made by volunteers, nature conservation professionals, natural historians and members of the public gathered through Butterfly Conservation's branches and scheme, local environmental records centre and other organisations. No specific methodology is required: occurrence records of any life-cycle stage of any butterfly species seen anywhere in the county at any time of the year by any recorders are accepted, subject to verification. However, standard minimum recording requirements exists and recorders are encouraged to adopt them (e.g. an exact date). Recorders are also encouraged to note the exact or approximate abundance of each species seen. Recorders are encouraged to use iRecord-linked online data capture such as iRecord Butterflies app. A secondary source of data is from the literature and museum specimens, particularly for pre-1970 records. For example, such records were extracted from the literature (in an unsystematic way and with a strong bias towards rarer species) by BRC for the Atlas of Butterflies in Britain and Ireland (Heath et al. 1984).

Citation

Butterfly distribution data from the Butterflies for the New Millennium recording scheme, courtesy of Butterfly Conservation.

Digitised records