Waarnemingen.be - Butterfly occurrences in Flanders and the Brussels Capital Region, Belgium

Version 1.2 published by Natuurpunt on 28 April 2016 Natuurpunt
Publication date:
28 April 2016
Published by:
CC0 1.0

Download the latest version of this resource data as a Darwin Core Archive (DwC-A) or the resource metadata as EML or RTF:

Data as a DwC-A file download 612,934 records in English (16 MB)  - Update frequency: annually
Metadata as an EML file download in English (22 KB)
Metadata as an RTF file download in English (18 KB)


Waarnemingen.be - Butterfly occurrences in Flanders and the Brussels Capital Region, Belgium is a species occurrence dataset published by Natuurpunt and described in Maes et al. 2016 (http://doi.org/10.3897/zookeys.585.8019). The dataset contains over 612,000 butterfly occurrences of 63 species, recorded by volunteers (citizen scientists), mainly since 2008. The occurrences are derived from the database http://www.waarnemingen.be, hosted at the nature conservation NGO Natuurpunt in collaboration with Stichting Natuurinformatie, and are georeferenced using the centroid of their respective 5 x 5 km² Universal Transverse Mercator (UTM) grid cell. Together with the dataset Maes et al. (2016, http://doi.org/10.15468/njgbmh), the dataset represents the most complete overview of butterflies in Flanders and the Brussels Capital Region (north Belgium).

Data Records

The data in this occurrence resource has been published as a Darwin Core Archive (DwC-A), which is a standardized format for sharing biodiversity data as a set of one or more data tables. The core data table contains 612,934 records.

This IPT archives the data and thus serves as the data repository. The data and resource metadata are available for download in the downloads section. The versions table lists other versions of the resource that have been made publicly available and allows tracking changes made to the resource over time.


The table below shows only published versions of the resource that are publicly accessible.

How to cite

Please be aware, this is an old version of the dataset.  Researchers should cite this work as follows:

Vanreusel W, Herremans M, Vantieghem P, Gielen K, Vlinderwerkgroep Natuurpunt, all butterfly recorders (2016): Waarnemingen.be - Butterfly occurrences in Flanders and the Brussels Capital Region, Belgium. Natuurpunt. Dataset/Occurrence. http://doi.org/10.15468/ezfbee Data paper: http://doi.org/10.3897/zookeys.585.8019


Researchers should respect the following rights statement:

The publisher and rights holder of this work is Natuurpunt. To the extent possible under law, the publisher has waived all rights to these data and has dedicated them to the Public Domain (CC0 1.0). Users may copy, modify, distribute and use the work, including for commercial purposes, without restriction.

GBIF Registration

This resource has been registered with GBIF, and assigned the following GBIF UUID: 1f968e89-ca96-4065-91a5-4858e736b5aa.  Natuurpunt publishes this resource, and is itself registered in GBIF as a data publisher endorsed by Belgian Biodiversity Platform.


Occurrence; Observation; butterflies; Lepidoptera; distribution; collection; literature; citizen science; observations; monitoring


Wouter Vanreusel
  • Metadata Provider
  • Originator
Celhoofd cel netwerken & data
Natuurpunt Studie
Coxiestraat 11
2800 Mechelen
Marc Herremans
  • Originator
  • Point Of Contact
Diensthoofd Natuurpunt Studie
Natuurpunt Studie
Coxiestraat 11
2800 Mechelen
Pieter Vantieghem
  • Originator
Vlinderwerkgroep Natuurpunt
Coxiestraat 11
2800 Mechelen
Karin Gielen
  • Originator
Administratief medewerker / Databeheerder
Natuurpunt Studie
Coxiestraat 11
2800 Mechelen
Peter Desmet
  • Metadata Provider
LifeWatch team coordinator
Research Institute for Nature and Forest (INBO)
Kliniekstraat 25
1070 Brussels
Brussels Capital Region

Geographic Coverage

Flanders and the Brussels Capital Region. These regions cover an area of 13,522 km² and 162 km² respectively (13,684 km² in total). This area is situated in the northern of Belgium and represents 45% of the Belgian territory. Flanders is largely covered by agricultural land and urban areas while the Brussels Capital Region is mainly urban. All distribution data were attributed to grid cells of 5 x 5 km² of the Universal Transverse Mercator (UTM) projection. The centroids of the 5 x 5 km² grid cells were calculated using the WGS84 projection with a coordinateUncertaintyInMeters of 3,769 meters (Wieczorek et al. 2004). In total, Flanders and the Brussels Capital Region cover 638 (622 with records) and 9 (all nine with records) grid cells, respectively. The grid cells without records only cover a very small area within Flanders.

Bounding Coordinates South West [50.68, 2.54], North East [51.51, 5.92]

Taxonomic Coverage

The datasets covers 49 of the 67 indigenous as well as 3 regular migrant butterfly species (Colias croceus, C. hyale, and Vanessa cardui). Aporia crataegi, Argynnis adippe, and Argynnis aglaja no longer have breeding populations in Flanders and recent observations are all considered as vagrant individuals in this dataset. 8 vagrant species with photographic evidence, that most likely spontaneously reached Flanders (Apatura ilia, Brenthis ino, Cupido argiades, Iphiclides podalirius, Lampides boeticus, Nymphalis xanthomelas, Polyommatus coridon and Pontia daplidice), are also included. Nomenclature is according to Fauna Europaea (http://www.faunaeur.org/full_results.php?id=7).

Kingdom Animalia (animals)
Phylum Arthropoda
Class Insecta (insects)
Order Lepidoptera (moths & butterflies)
Family Hesperiidae, Lycaenidae, Nymphalidae, Papilionidae, Pieridae

Temporal Coverage

Start Date / End Date 1900-01-25 / 2014-12-31

Sampling Methods

Butterfly observations (species, date, location, observer) were recorded by volunteers/citizen scientists at http://www.waarnemingen.be. Since 2011, 69% of the records had a precision of 25m or less. Because of the increasing popularity of mobile apps using GPS readings in the field, this proportion increased with 5% per year to reach 77% in 2015.

Study Extent See geographic coverage.
Quality Control Recorded data are constantly verified by butterfly experts (including professional entomologists) taking collection specimens, the observer’s species knowledge, added photographs and known species list of locations into account. The validation procedure from www.waarnemingen.be consists of an interactive procedure in which observers can be asked for additional information by a team of validators, after which the validator manually adds a validation status. Records that are not manually validated are additionally checked by an automated validation procedure that takes into account the number of manually validated observations within a specified date and distance range. 11% of the butterfly records submitted to the data portal www.waarnemingen.be are supported by photographs. The validation status is indicated in the field identificationVerificationStatus.

Method step description:

  1. Not provided.

Bibliographic Citations

  1. Maes D, Vanreusel W, Herremans M, Vantieghem P, Brosens D, Gielen K, Beck O, Van Dyck H, Desmet P, Vlinderwerkgroep Natuurpunt (2016) A database on the distribution of butterflies (Lepidoptera) in northern Belgium (Flanders and the Brussels Capital Region). ZooKeys 585: 143-156. doi: 10.3897/zookeys.585.8019 http://doi.org/10.3897/zookeys.585.8019
  2. Daniëls L (1991). JNM-Dagvlinderprojekt. Euglena, 10: 26-27.
  3. De Prins W (1998). Catalogue of the Lepidoptera of Belgium, Koninklijk Belgisch Instituut voor Natuurwetenschappen, Brussel, 235 pp.
  4. De Selys-Longchamps E (1837). Catalogue des Lepidoptères ou Papillons de la Belgique. Luik. 14-21.
  5. Hackray J, Sarlet L, Berger L (1969). Catalogue des macrolépidoptères de Belgique. Lambillionea (suppl.), 67: 1-256.
  6. Kühn E, Feldmann R, Harpke A, Hirneisen N, Musche M, Leopold P, Settele J (2008). Getting the public involved in butterfly conservation: Lessons learned from a new monitoring scheme in Germany. Israel Journal of Ecology & Evolution, 54: 89-103. doi: 10.1560/IJEE.54.1.89 http://doi.org/10.1560/IJEE.54.1.89
  7. Maes D, Van Dyck H (1996). Een gedocumenteerde Rode lijst van de dagvlinders van Vlaanderen, Mededelingen van het Instituut voor Natuurbehoud Instituut voor Natuurbehoud, Brussel, 154 pp.
  8. Maes D, Van Dyck H (1999). Dagvlinders in Vlaanderen - Ecologie, verspreiding en behoud, Stichting Leefmilieu i.s.m. Instituut voor Natuurbehoud en Vlaamse Vlinderwerkgroep, Antwerpen/Brussel, 480 pp.
  9. Maes D, Vanreusel W, Jacobs I, Berwaerts K, Van Dyck H (2012). Applying IUCN Red List criteria at a small regional level: A test case with butterflies in Flanders (north Belgium). Biological Conservation, 145: 258-266. doi: 10.1016/j.biocon.2011.11.021 http://doi.org/10.1016/j.biocon.2011.11.021
  10. Maes D, Vanreusel W, Van Dyck H (2013). Dagvlinders in Vlaanderen: nieuwe kennis voor betere actie, Uitgeverij Lannoo nv, Tielt, 542 pp.
  11. Maes D, Brosens D, Beck O, Van Dyck H, Desmet P, Vlinderwerkgroep Natuurpunt, all butterfly recorders (2016): Vlinderdatabank - Butterflies in Flanders and the Brussels Capital Region, Belgium. Research Institute for Nature and Forest (INBO). Dataset/Occurrence. http://doi.org/10.15468/njgbmh Data paper: http://doi.org/10.3897/zookeys.585.8019 http://doi.org/10.15468/njgbmh
  12. Wieczorek J, Guo QG, Hijmans RJ (2004). The point-radius method for georeferencing locality descriptions and calculating associated uncertainty. International Journal of Geographical Information Science, 18: 745-767. doi: 10.1080/13658810412331280211 http://doi.org/10.1080/13658810412331280211

Additional Metadata

To allow anyone to use this dataset, we have released the data to the public domain under a Creative Commons Zero waiver (http://creativecommons.org/publicdomain/zero/1.0/). We would appreciate however, if you read and follow these norms for data use (http://www.natuurpunt.be/normen-voor-datagebruik [in Dutch]) and provide a link to the original dataset (http://doi.org/10.15468/ezfbee) whenever possible. If you use these data for a scientific paper, please cite the dataset following the applicable citation norms and/or consider us for co-authorship. We are always interested to know how you have used or visualized the data, or to provide more information, so please contact us via the contact information provided in the metadata, marc.herremans@natuurpunt.be or opendata@inbo.be. Information withheld: in the original database, the observer’s name, the exact XY-coordinates and the toponym are known.

Purpose Butterflies are among the best studied insects in the world and have always attracted the attention of both professional researchers, amateur naturalists, butterfly collectors, and the wider public (Kühn et al. 2008). Butterflies are widely considered as interesting study systems for ecology, evolution, behaviour, and conservation biology (e.g., Watt and Boggs 2003). Many butterflies have been collected and subsequently stored in museum or private collections. Furthermore, entomologists have often published lists of observed species during excursions to special habitats or have made overviews of regional or national butterfly faunas. In Belgium, entomology in general and lepidopterology in particular, have a long tradition with the first faunas already published only seven years after its independence in 1830 (De Selys-Longchamps 1837). Since then, several authors have updated the Belgian butterfly fauna based on collections or observations (e.g., Hackray et al. 1969; De Prins 1998). In 1991, the youth and nature organization Jeugdbond voor Natuur en Milieu (JNM) launched a butterfly project with the aim to publish a distribution atlas of the butterflies of Flanders, north Belgium (Daniëls 1991). To do so, a first step consisted of collecting all historical collection and literature data. Secondly, a working group was organised in cooperation between JNM, De Wielewaal (which later became Natuurpunt) and the INBO that set up a citizen science project to obtain as many butterfly observations with a good spatial coverage over Flanders. The data gathered during this project (period 1991-1998) were used to compile a first Red List (Maes and Van Dyck 1996) and a distribution atlas of butterflies in Flanders, including the Brussels Capital Region (Maes and Van Dyck 1999). Recently, both the Red List (Maes et al. 2012) and the distribution atlas (Maes et al. 2013) were updated using recent distribution data recorded through www.waarnemingen.be, a data portal launched by Natuurpunt, the largest nature conservation NGO in Belgium, where citizen-scientists can store and keep track of their recordings. Here, we publish both the historical and the more recent data used for the Red List and the distribution atlases as a data paper on a UTM grid cell resolution of 5 x 5 km².
Alternative Identifiers 1f968e89-ca96-4065-91a5-4858e736b5aa