DOI: 10.5061/dryad.ghx3ffbpf
title: Recordings of aquatic macroinvertebrates by volunteers (2018-2020) and professionals (2013-2019) in the Netherlands

description: Volunteers have become more and more involved in monitoring the quality of
 the environment in which they live. Traditionally, water quality
 monitoring is the field of professionals at water authorities, however,
 community initiatives have been undertaken to monitor abiotic conditions
 in waterbodies. To date, biological water quality assessment based on data
 collected by volunteers remains scarce. A citizen science project on
 biological water quality assessment was launched in the Netherlands in
 2018. In this project, volunteers collect macroinvertebrates from in a
 nearby waterbody, identify and count the number of specimens, and register
 their catch through a web portal to instantaneously receive a water
 quality score based on their data. This study compares the data from the
 volunteers with the data from professionals focussing on type of sampled
 waterbody, sampling period, observed animals and water quality. The
 analyses show that volunteers and professionals seldomly sample the same
 waterbody, that there is some overlap in sampling period, and that
 volunteers more frequently sampled smaller water bodies and more urban
 waters. The citizen science project is thus yielding useful spatially and
 temporally complementarity data. The assessments by volunteers and
 professionals likely differ in character and thoroughness. Volunteers
 collected significantly lower numbers of animals per sample and fewer
 animals from soft sediments but more mobile individuals from the open
 water column. As a result, the water quality scores between volunteers and
 professionals differ. To bridge these differences, new tools and processes
 may need to be developed to further increase the value of monitoring
 biological water quality by volunteers for professionals.
description: The data from the citizen science project were retrieved from the
 original website 'waterdiertjes.nl' and cover the period
 2018-2020. Only relevant fields are included in the dataset being location
 code, year, month and date of samping, user ID, watertype, latin name of
 taxa and abundance. Multiple recordings at the same location on the same
 date and nearly time were aggregated into one sampling. Each line equals
 the abundance of one taxon at a specific location and specific date.
 Taxonomy follows the British Freshwater name trail (Orton R, Bebbington A,
 Bebbingon J. 1996. The freshwater name trail. Field Studies Council
 Publications, Telford, UK.) The data from the
 professionals were retrieved from the original website
 'waterkwaliteitsportaal.nl' and cover the period 2013-2019. Only
 macroinvertebrate recordings were retrieved that were collected following
 the multihabitat approach (Barbour, Stribling, Verdonschot. 2006. The
 multihabitat approach of USEPA’s rapid bioassessment protocols: benthic
 macroinvertebrates. Limnetica. 25: 839-850) with a standardized sampling
 length of 5 m. The data were aggregated to the same taxonomic level as
 used by the citizen science project 'waterdiertjes.nl' and thus
 following the British Freshwater name trail (Orton R, Bebbington A,
 Bebbingon J. 1996. The freshwater name trail. Field Studies Council
 Publications, Telford, UK.). All other taxa were disregarded.