Invasive species - American bullfrog (Lithobates catesbeianus) in Flanders, Belgium (post 2018)

Latest version published by Research Institute for Nature and Forest (INBO) on 13 May 2024 Research Institute for Nature and Forest (INBO)

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 35,193 records in English (1 MB) - Update frequency: unknown
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Invasive species - American bullfrog (Lithobates catesbeianus) in Flanders, Belgium (Post 2018) is a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset contains over 24600 occurrences (40 % of which are American bullfrogs) sampled between 2019 until now, in the months April to October. The occurrences were collected through fieldwork and the framework of bullfrog management. Captured bullfrogs were almost always removed from the environment and humanely killed, while the other occurrences are recorded bycatch, which were released upon catch (see bibliography for detailed descriptions of the methods). Therefore, caution is advised when using these data for trend analysis, distribution range calculation, or other. Issues with the dataset can be reported at https://github.com/inbo/sk-analyse

We strongly believe an open attitude is essential for tackling the IAS problem (Groom et al. 2015). 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 it however if you read and follow these norms for data use (http://www.inbo.be/en/norms-for-data-use) and provide a link to the original dataset (https://doi.org/10.15468/daf62d) 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, opendata@inbo.be or https://twitter.com/LifeWatchINBO.

Data from 2010 to 2018 can be found here: https://doi.org/10.15468/2hqkqn

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 35,193 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:

Devisscher S, Brosens D (2024). Invasive species - American bullfrog (Lithobates catesbeianus) in Flanders, Belgium (post 2018). Version 1.32. Research Institute for Nature and Forest (INBO). Occurrence dataset. https://ipt.inbo.be/resource?r=invasive-bullfrog-occurrences2&v=1.32


Researchers should respect the following rights statement:

The publisher and rights holder of this work is Research Institute for Nature and Forest (INBO). 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: 5b8bcba7-cecb-4d95-9865-2830cd4e35aa.  Research Institute for Nature and Forest (INBO) publishes this resource, and is itself registered in GBIF as a data publisher endorsed by Belgian Biodiversity Platform.


Occurrence; American bullfrog; Lithobates catesbeianus; Rana catesbeiana; amphibians; invasive alien species; non-native species; management; captures; eradication; Flanders


Sander Devisscher
  • Metadata Provider
  • Originator
  • Point Of Contact
Research Institute for Nature and Forest (INBO)
Dimtri Brosens
  • Originator
Research Institute for Nature and Forest (INBO)/ Belgian Biodiversity Platform

Geographic Coverage

Flanders, Belgium. Most of the data originate from the province of Antwerp, as this province currently holds the main stronghold of the American bullfrog population.

Bounding Coordinates South West [50.646, 2.483], North East [51.543, 6.086]

Taxonomic Coverage

American bullfrog (Lithobates catesbeianus (Shaw 1802) syn. Rana catesbeiana Shaw 1802)

Kingdom Animalia
Species American bullfrog (Lithobates catesbeianus (Shaw 1802) syn. Rana catesbeiana Shaw 1802) (Amerikaanse stierkikker)

Temporal Coverage

Start Date / End Date 2019-05-07 / 2022-01-01

Sampling Methods

Sampling occurs yearly between April and October. Most of the captures are made with paired fyke nets which are placed at the bottom of ponds and lakes for about 24 hours, but other methods are used as well (indicated in samplingProtocol). With each capture, the number of bullfrogs at each developmental stage is recorded (indicated in lifeStage), as well as bycatch species (native amphibians, fish, non-native crayfish, invertebrates) which were released upon catch. Also recorded are date, location, number of employees involved, and start and end time of the capture event.

Study Extent Bullfrog infested ponds and lakes in Flanders, Belgium.
Quality Control Data collection and species identifications were performed by professional scientists or research assistants.

Method step description:

  1. Data is collected in the field
  2. Raw data for Dwc mapping was created: https://github.com/inbo/sk-analyse/tree/main/output
  3. all data was mapped to DwC: https://github.com/inbo/sk-analyse/tree/main/script
  4. all data was imported in INBO IPT, registered and published to GBIF

Additional Metadata

Purpose The increasing establishment of invasive alien species (IAS) present many challenges for policy makers, managers and researchers. An adequate response to IAS requires accurate and up-to-date information on their distribution. This information can only be provided if IAS data are available and usable by all. American bullfrog is a high profile IAS. Due to its broad global distribution and widespread effects on native biodiversity through various impact mechanisms, American bullfrog is listed as one of the top 100 most invasive alien species in the world by the IUCN (Lowe et al. 2000). The species is suspected to cause substantial ecological damage around large parts of the globe, exerting an additional pressure to already declining amphibian populations. Negative impacts on native biota entail competition, predation and the transmission of pathogens. Subsequently, in Europe, it is listed on the SEBI worst list of invasive non-native species with high impact on biodiversity, as well as the DAISIE list of the worst invasive aliens in Europe. For the same reasons, the species is included in the appendix to the Bern Convention recommendation n° 77 (1999) as a species which has proved to be a strong threat to biological diversity and for which eradication is strongly recommended. Moreover, the EU Wildlife Trade Regulation (338/97) Appendix B prohibits import of the species into the EU since December 1997. It is listed as a species of EU concern sensu the EU Regulation 1143/2014 on the prevention and management of the introduction and spread of IAS. The data in this dataset are useful for scientific purposes such as distribution modelling, as well as early warning and rapid response protocols, but note that bullfrogs (40% of the occurrences) were almost always removed from the environment during the research and eradication campaign.
Alternative Identifiers 5b8bcba7-cecb-4d95-9865-2830cd4e35aa