Erratum: Using DNA metabarcoding for assessing chironomid diversity and community change in mosquito controlled temporary wet-lands (Metabarcoding and Metagenomics 2 (e21060) DOI: 10.3897/mbmg.2.21060)

Abstract

Explanation regarding the background leading to this corrigendum The main reasons for this corrigendum were discrepancies between the detected number of chironomids in a report from 2014 and the MBMG article, published in 2018. In the MBMG article from 2018, overall more chironomids were reported that were not detected in the report from 2014. The reasons for this are outlined below. In general, the abundance data used in this study were part of a project conducted in 2013, which investigated the influence of mosquito control with Bti on the food web. This study was approved and financed by the town Neustadt an der Weinstrasse (Germany). The township requested a project report, which was due in March 2014. By this time, the data were not finally evaluated. In particular, a taxonomic training course for determining Chironomidae subfamilies was attended later in the year 2014 by some of the project participants. After this training, we found out that many chironomids of the subfamily Orthocladiinae were wrongly determined as Cecidomyiidae. This had direct impacts on the results and created differences in comparison to the report that was published 2014. All detected differences between the report and this manuscript are listed below in Table SI1. In this context of clarification, we came across some additional mistakes in the Microsoft Access database query of the abundance data, where a filter was missing for excluding traps that dried out during summer. In addition, the project in 2013 was conducted over a longer period, namely 18 weeks after initial Bti application (WAA). In the MBMG article, we only used the data until WAA13, because after this week, too many traps dried out, with only some data points for aquatic insects remaining. However, in the originally-published MBMG article, we falsely included emergence data of all individuals until WAA18, including terrestrial taxa from traps that dried out. This mistake has now been corrected, which led to a reduction in the number of detected taxa and individuals, including chironomids and mosquitoes (see article in “tracked changes” below). For full transparency, a new Suppl. material 3 with all abundance data has now been added to the corrected version of our article. Due to the strong within-site heterogeneity and the resulting highly variable numbers of chironomids detected per trap within each site, we reduced our overall statement of a clearly negative Bti effect on the chironomid community and discuss the need for more true replicates to overcome the problem of a highly-patchy chironomid distribution within a water body. We have restructured the start of the abstract and introduction to emphasise the importance of chironomids in bioassessments (by moving sections of the text up). The authors apologize for any inconveniences resulting from these changes and want to explicitly thank the editorial staff for the very thorough review of our study and support in correcting the mistakes. Finally, we would like to point out that the mistake only affected the overall abundance data, but the metabarcoding part of the study was not concerned and has not been changed.