Checklist of alien species in the Scheldt estuary in Flanders, Belgium

22211949-9a6e-445f-86c0-6a0e019bc055 https://ipt.inbo.be/resource?r=alien-scheldt-checklist Checklist of alien species in the Scheldt estuary in Flanders, Belgium Jan Soors Research Institute for Nature and Forest (INBO)

jan.soors@inbo.be Frank Van de Meutter Research Institute for Nature and Forest (INBO)

frank.vandemeutter@inbo.be 0000-0002-9850-1860 Gunther Van Ryckeghem Research Institute for Nature and Forest (INBO)

gunther.vanryckeghem@inbo.be 0000-0001-8788-0001 Tim Adriaens Research Institute for Nature and Forest (INBO)

tim.adriaens@inbo.be 0000-0001-7268-4200 Lien Reyserhove Research Institute for Nature and Forest (INBO)

lien.reyserhove@inbo.be 0000-0001-7484-9267 Sanne Govaert Reserach Institute for Nature and Forest (INBO)

0000-0002-8939-1305 Lien Reyserhove Research Institute for Nature and Forest (INBO)

lien.reyserhove@inbo.be 0000-0001-7484-9267 Frank Van de Meutter Research Institute for Nature and Forest (INBO)

frank.vandemeutter@inbo.be 0000-0002-9850-1860 Jan Soors Research Institute for Nature and Forest (INBO)

2025-12-17 eng The Checklist of alien species in the Scheldt estuary in Flanders, Belgium is a species checklist dataset published by the Research Institute for Nature and Forest (INBO). It contains information on 61 invertebrate alien species occurring in the Belgian Scheldt estuary, detected between 1835 and now. Here it is published as a standardized Darwin Core Archive and includes for each species: the scientific name, higher taxonomy, stable taxon ID (in the taxon core), the year of first introduction and/or last assessment in Flanders (given as a year or year range in the event date in the distribution extension), coarse habitat information (in the species profile extension) and the native range(s), pathway(s) of introduction and degree of establishment in Flanders (in the description extension). Issues with the dataset can be reported at https://github.com/trias-project/alien-scheldt-checklistWe have released this dataset to the public domain under a Creative Commons Zero waiver. We would appreciate it if you follow the INBO norms for data use (https://www.inbo.be/en/norms-data-use) when using the data. If you have any questions regarding this dataset, don't hesitate to contact us via the contact information provided in the metadata or via opendata@inbo.be.This dataset was published as open data for the TrIAS project (Tracking Invasive Alien Species http://trias-project.be, Vanderhoeven et al. 2017), with technical support provided by the Research Institute for Nature and Forest (INBO). It is selected as one of the authoritative sources for the compilation of a unified and reproducible checklist of alien species in Belgium. Checklist GBIF Dataset Type Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_type_2015-07-10.xml Inventorythematic GBIF Dataset Subtype Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_subtype.xml checklist inventory alien species Scheldt estuaries Belgium Flanders TrIAS n/a 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. Creative Commons Zero v1.0 Universal https://spdx.org/licenses/CC0-1.0.html CC0-1.0 The dataset includes information on the presence of alien invertebrate species in Flanders, Belgium 2.53 5.94 51.51 50.67 1865 2020 This checklist includes over 62 alien invertebrate species present in Flanders, Belgium kingdom Animalia phylum Annelida phylum Arthropoda phylum Cnidaria phylum Mollusca phylum Platyhelminthes asNeeded Frank Van de Meutter Research Institute for Nature and Forest (INBO)

frank.vandemeutter@inbo.be 0000-0002-9850-1860 The source data for this standardized checklist is a Google Spreadsheet and re-uploaded regularly at https://docs.google.com/spreadsheets/d/1V_rQhyz_AjszobCMxBe-xFWI3kUNLrYzMeqyUNt3Vc4/edit#gid=0 This raw data file was uploaded to a GitHub repository (https://github.com/trias-project/alien-scheldt-checklist). We developed a RMarkdown script to document and perform the transformation of the data to Darwin Core, which includes the following steps: Perform some basic data cleaning of the raw data. Generate stable and unique identifiers for each taxon (taxonID). Create a taxon core file (http://rs.gbif.org/core/dwc_taxon.xml). Create a distribution extension file (http://rs.gbif.org/extension/gbif/1.0/distribution.xml), including standardization of the distribution date range and event dates. Create a species profile extension file (http://rs.gbif.org/extension/gbif/1.0/speciesprofile.xml), with coarse habitat information. Create a description extension file (http://rs.gbif.org/extension/gbif/1.0/description.xml), with standardized pathway of introduction (using the pathway vocabulary from the Convention on Biological Diversity (2014)), native range, and degree of establishment (based on Blackburn et al. (2011)). The resulting Darwin Core data files are uploaded to the INBO IPT and documented with metadata. The dataset is published and registered with GBIF. Within the Belgian part of the Schelde estuary, benthos has been monitored by INBO since 1996. Most of the alien species were found since then. Prior to 2008, sampling was conducted every third year at fixed intertidal and subtidal stations in an increasing quantity of sites: from 51 sampling sites in 1999 up to 75 in 2005. At each sampling site, 3 core samples (diameter: 3.5 cm; depth: 10 cm) were collected. In case of subtidal samples, these were obtained from a Reineck boxcorer (diameter: 15 cm; depth: 10 cm). Sampler size was chosen to reduce highly laborious sorting effort of samples with high densities of oligochaetes (occasionally more than 1 106 individuals m-²). Sediment samples were stored in 4% formaldehyde. In the laboratory, samples were sieved in two steps over mesh sizes of 250 μm and 1000 μm. Benthic invertebrates were sorted, identified to species level, and counted. Since 2008, samples have been collected each year, following a stratified random sampling design; 212 stations are stratified by salinity zone, subtidal depth, and intertidal elevation. Two core samples (diameter: 4.5 cm; depth: 15cm) were collected at each station, fixed in 4% formaldehyde, and taken to the laboratory. These were sieved over mesh sizes of 500 μm and 1000 μm and subsequently treated as described for the samples collected prior to 2008. Since 2013 hyperbenthic monitoring occurs at 6 fixed stations; five locations along the Scheldt and one along its major tributary the Rupel. Other locations are sporadically sampled. For regular monitoring a bongonet (diameter, mesh 1mm) is pulled back and forth by 2 persons at low tide over 100m (total distance 200m). As part of projects, occasional samplings occur with the bongo net or less frequent using a benthic sledge (width 1m, heigh 50cm). Samples are always taken along the shoreline at low tide, with the exception of a series of bongo net samples taken from a boat near the surface in the navigation channel. All samples were fully sorted and all species identified to the lowest level possible. Very large samples (1000s of specimens) were subsampled (usually 1/8). All records are individually validated by species experts (resource creators of this dataset). Tracking Invasive Alien Species (TrIAS) Tim Adriaens 0000-0001-7268-4200 author Peter Desmet 0000-0002-8442-8025 author Quentin Groom 0000-0002-0596-5376 principalInvestigator Diederik Strubbe 0000-0002-2613-4985 author Sonia Vanderhoeven 0000-0002-6298-5373 author Imagine a future where dynamically, from year to year, we can track the progression of alien species (AS), identify emerging species, assess their current and future risk and timely inform policy in a seamless data-driven workflow. One that is built on open science and open data infrastructures. By using international biodiversity standards and facilities, we would ensure interoperability, repeatability and sustainability. This would make the process adaptable to future requirements in an evolving IAS policy landscape both locally and internationally. The project Tracking Invasive Alien Species (TrIAS) aims to do this for Belgium. For a full project description, see Vanderhoeven et al. (2017, https://doi.org/10.3897/rio.3.e13414). TrIAS is funded by the Belgian Science Policy Office (BELSPO) call for Belgian Research Action through Interdisciplinary Networks (BRAIN). Belgium The project builds on two components: 1) The establishment of a data mobilization framework for alien species data from diverse data sources and 2) the development of data-driven procedures for risk evaluation based on risk modelling, risk mapping and risk assessment. TrIAS uses facilities from the Global Biodiversity Information Facility (GBIF, http://www.gbif.org), standards from the Biodiversity Information Standards organization (TDWG, http://www.tdwg.org) and expertise from the Open science lab for biodiversity (https://oscibio.inbo.be) to create and facilitate a systematic workflow. Alien species data are gathered from a large set of regional, national and international initiatives, including citizen science data, with a wide taxonomic scope from marine, terrestrial and freshwater environments. Observation data are funnelled in repeatable ways to GBIF. In parallel, a Belgian checklist of alien species is established, benefiting from various taxonomic and project-based checklists foreseen for GBIF publication. 2021-04-30T13:49:30.332+02:00 dataset Soors J, Van de Meutter F, Van Ryckeghem G, Adriaens T, Reyserhove L, Govaert S (2025). Checklist of alien species in the Scheldt estuary in Flanders, Belgium. Version 1.9. Research Institute for Nature and Forest (INBO). Checklist dataset. https://ipt.inbo.be/resource?r=alien-scheldt-checklist&v=1.9 Blackburn TM, Pysek P, Bacher S, Carlton JT, Duncan RP, Jarosik V, Wilson JRU & Richardson DM (2011) A proposed unified framework for biological invasions. Trends in Ecology and Evolution 26: 333-339. Convention on Biological Diversity (2014) Pathways of introduction of invasive species, their prioritization and management. UNEP/CBD/SBSTTA/18/9/Add.1. Secretariat of the Convention on Biological Diversity, Montreal. https://www.cbd.int/doc/meetings/sbstta/sbstta-18/official/sbstta-18-09-add1-en.pdf Vanderhoeven S, Adriaens T, Desmet P, Strubbe D, Backeljau T, Barbier Y, Brosens D, Cigar J, Coupremanne M, De Troch R, Eggermont H, Heughebaert A, Hostens K, Huybrechts P, Jacquemart A, Lens L, Monty A, Paquet J, Prévot C, Robertson T, Termonia P, Van De Kerchove R, Van Hoey G, Van Schaeybroeck B, Vercayie D, Verleye T, Welby S, Groom Q (2017) Tracking Invasive Alien Species (TrIAS): Building a data-driven framework to inform Collection data 22211949-9a6e-445f-86c0-6a0e019bc055/v1.9.xml