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

Latest version published by Natuurpunt on Apr 30, 2021 Natuurpunt
Publication date:
30 April 2021
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 1,298,346 records in English (41 MB) - Update frequency: not planned
Metadata as an EML file download in English (18 KB)
Metadata as an RTF file download in English (14 KB)


Waarnemingen.be - Butterfly occurrences in Flanders and the Brussels Capital Region, Belgium is a species occurrence dataset published by Natuurpunt and described (v1.4) in Maes et al. (2016, https://doi.org/10.3897/zookeys.585.8019). The dataset contains close to 1.3 million butterfly (Lepidoptera excluding moths) occurrences of 69 naturally occurring species (native, vagrant or migrant species), recorded by volunteers (citizen scientists), mainly since 2008. Together with the dataset Maes et al. (2016, https://doi.org/10.15468/njgbmh), it represents the most complete overview of butterflies in Flanders and the Brussels Capital Region (north Belgium). The occurrences are derived from the database http://www.waarnemingen.be, hosted at the nature conservation NGO Natuurpunt in collaboration with Stichting Natuurinformatie. Standardized information regarding the occurrence's sex, lifeStage, behavior, occurrenceRemarks, and samplingProtocol is included as well.

Generalized and/or withheld information: location information is generalized to 5 x 5 km² Universal Transverse Mercator (UTM) grid cells. Observer name, exact XY-coordinates, toponyms, and photographs are not included in the published dataset, but are known in the source database.

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) and provide a link to the original dataset (https://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 provide more information or know how you have used the data, so please contact us via the contact information provided in the metadata or natuurdata@natuurpunt.be.

The publication of this dataset is supported by INBO and funded by Research Foundation - Flanders (FWO) as part of the Belgian contribution to LifeWatch.

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

Researchers should cite this work as follows:

Vanreusel W, Herremans M, Vantieghem P, Gielen K, Desmet P, Swinnen K, Vlinderwerkgroep Natuurpunt, all butterfly recorders (2021): Waarnemingen.be - Butterfly occurrences in Flanders and the Brussels Capital Region, Belgium. v1.10. Natuurpunt. Dataset/Occurrence. https://doi.org/10.15468/ezfbee


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; observations; citizen science; Natuurpunt; waarnemingen.be; observation.org; Occurrence


Wouter Vanreusel
  • Metadata Provider
  • Originator
Natuurpunt Studie
Marc Herremans
  • Originator
  • Point Of Contact
Natuurpunt Studie
Pieter Vantieghem
  • Originator
Vlinderwerkgroep Natuurpunt
Karin Gielen
  • Originator
Natuurpunt Studie
Peter Desmet
  • Metadata Provider
  • Originator
Research Institute for Nature and Forest (INBO)
Kristijn Swinnen
all butterfly recorders

Geographic Coverage

Flanders and the Brussels Capital Region. These regions are situated in the north of Belgium and cover an area of 13,522 km² and 162 km² respectively (13,684 km² in total or 45% of the Belgian territory). Flanders is largely covered by agricultural land and urban areas while the Brussels Capital Region is mainly urban. All occurrence data are generalized to grid cells of 5 x 5 km² of the Universal Transverse Mercator (UTM) coordinate system, with the grid codes indicated in the field verbatimCoordinates. The WGS84 centroids of these grid cells are calculated in decimalLatitude/Longitude with a coordinateUncertaintyInMeters of 3,769 meters using Wieczorek et al. (2004). The coordinateUncertaintyInMeters is larger than the expected 3,536 meters due to an unknown geodetic datum being used for older observations.

Bounding Coordinates South West [50.67, 2.53], North East [51.51, 5.94]

Taxonomic Coverage

The dataset covers 69 butterflies species (Lepidoptera excluding moths) observed in Flanders and the Brussels Capital Region, Belgium. It includes 50 of the 69 native species, 3 regular migrants (Colias crocea, C. hyale, and Vanessa cardui) and 2 new-native species that are breeding in Flanders (Brenthis daphne and Pieris manni). 5 species (Aporia crataegi, Boloria selene, Coenonympha tullia, Fabriciana adippe, and Speyeria aglaja) no longer have breeding populations in Flanders and recent observations are all considered as vagrant individuals in this dataset. The Satyrium pruni observations are probably introduced. The remaining 8 species are vagrants that most likely spontaneously reached Flanders (Apatura ilia, Brenthis ino, Cupido argiades, Iphiclides podalirius, Lampides boeticus, Lysandra coridon, Nymphalis xanthomelas, and Pontia daplidice). Nomenclature is according to Fauna Europaea (https://fauna-eu.org/).

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

Temporal Coverage

Start Date / End Date 1902-07-15 / 2018-12-31

Sampling Methods

The observations (species, date, location, observer) were recorded by volunteers (citizen scientists) at http://www.waarnemingen.be.

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 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. 10% of the observations in this dataset are supported by a photograph on waarnemingen.be. The validation status is indicated in the field identificationVerificationStatus, the link to the original record in references.

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. https://doi.org/10.3897/zookeys.585.8019
  2. 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. https://doi.org/10.15468/njgbmh Data paper: https://doi.org/10.3897/zookeys.585.8019
  3. 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. https://doi.org/10.1080/13658810412331280211

Additional Metadata

Alternative Identifiers 1f968e89-ca96-4065-91a5-4858e736b5aa