The Non-native Species First Records dataset (short: FirstRecords) contains years of first records when a non-native species was first recorded in a region (mostly countries, but also sub-national units). The first records were gathered in a collaborative effort involving >50 researchers worldwide from various sources consisting of online databases, scientific publications, reports and personal collections. A full list of data sources is provided in the file "FirstRecord_main_dataset_sources.csv". The dataset and the workflow to generate the dataset are described in detail here: Truong Renard, T. & Seebens, H. (under review) A global dataset of first records of non-native species. Please cite this publication when using the dataset. The publication also contains usage notes, which should be carefully read before using this dataset. The publication also includes a detailed description of the randomisation process for first records provided as time intervals, the handling of first records without permission for sharing, and the assignment of confidence levels. The repository provides the following files: FirstRecords_dataset_public_v.4.0.csv: Main dataset containing information of taxon, location, invasion status, and first record FirstRecords_dataset_public_v.4.0.csv: Table providing taxonomic information for each taxon in the FirstRecords dataset including original names FirstRecords_main_dataset_sources.csv: Table of data sources used to compile the FirstRecords dataset FirstRecords_location_table_public_v.4.0.csv: Table of locations including their original names IntroData_raw_2026_public.xlsx: Input dataset of the records before harmonisation. This dataset should only be used for re-running the workflow rather than any analyses. The workflow to generate the FirstRecords dataset is available on Zenodo: ... Key publications using this dataset and providing more information about potentials and limitations are: Seebens, H., Blackburn, T. M., Dyer, E. E., Genovesi, P., Hulme, P. E., Jeschke, J. M., … Essl, F. (2017). No saturation in the accumulation of alien species worldwide. Nature Communications, 8(1), 14435. https://doi.org/10.1038/ncomms14435 Seebens, H., Blackburn, T. M., Dyer, E. E., Genovesi, P., Hulme, P. E., Jeschke, J. M., … Essl, F. (2018). Global rise in emerging alien species results from increased accessibility of new source pools. Proceedings of the National Academy of Sciences, 115(10), E2264–E2273. https://doi.org/10.1073/pnas.1719429115 Seebens H, Bacher S, Blackburn TM, Capinha C, Dawson W, Dullinger S, Genovesi P, Hulme PE, Kleunen M, Kühn I, Jeschke JM, Lenzner B, Liebhold AM, Pattison Z, Pergl J, Pyšek P, Winter M, Essl F (2021) Projecting the continental accumulation of alien species through to 2050. Global Change Biology 27: 970–982. https://doi.org/10.1111/gcb.15333 

Version 4.0 represents a fully revised and extended version of 3.1. The workflow to generate the dataset has been rewritten and published, making the workflow fully transparent and reproducible. Among others, the new version contains a confidence level for each first record to indicate the quality of the originally provided information on first record.