Understanding sampling and taxonomic biases recorded by citizen scientists


Projects involving citizen scientists have greatly increased over the last decade and understanding errors associated with such projects has been identified as an important step. NatureWatch NZ is a biodiversity recording system accessible to members of the public. The “NZ wasps, ants, bees and parasitoids (Hymenoptera) project” was initiated within NatureWatch NZ in December 2012, and comparisons were analysed between these records and the known Hymenoptera fauna of the New Zealand region. Over the course of 1 year 25 members contributed 360 records from 186 taxa, including the discovery of several introduced species new to New Zealand. There was a strong geographical bias to the records, with the majority being based around the major cities. Aculeates (stinging wasps) were significantly over-represented in the NatureWatch records. Only half (55 %) of taxa were identified to species level, with a further 28 % at genus level, and 17 % identified above genus level (family, order). Furthermore, the majority (65 %) of taxa were recorded only once, and only a few taxa were recorded >5 times (top records were “Ichneumonidae”, “Hymenoptera”, Anthidium manicatum, and Apis mellifera). It is probable that these same biases also exist for many other taxonomic groups in projects operated by citizen scientists lacking set protocols. Caution should be exercised on the subsequent use, compilation, and analysis of citizen science, especially without prior examination of records and potential biases.

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Thanks to all the NatureWatch NZ contributors of the Hymenoptera project. Thanks to the two anonymous reviewers for improving the manuscript. This work was supported by the MBIE through funding of the “Defining New Zealand’s Land Biota” programme. The project and its details are available to view at http://naturewatch.org.nz/projects/nz-wasps-ants-bees-and-parasitoids-hymenoptera (registration required).

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Correspondence to Darren F. Ward.

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Ward, D.F. Understanding sampling and taxonomic biases recorded by citizen scientists. J Insect Conserv 18, 753–756 (2014). https://doi.org/10.1007/s10841-014-9676-y

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  • Conservation
  • Public
  • Hymenoptera
  • New Zealand
  • Observation