“nützLINK” – a monitoring approach for beneficial arthropods in agricultural landscapes in Germany

Abstract: Reports of global declines have highlighted the need for reliable long-term estimates of insect populations to identify potential drivers of declines, perform taxa-specific risk assessments, and to measure potential effects of implemented conservation strategies. In this context, data on groups providing important ecosystem services is of particular interest. The MonViA project aims to address this by establishing a comprehensive long-term monitoring in agricultural landscapes in Germany.
In this study, a monitoring approach for hoverflies, which provide both pollination (adults)
and pest control (larvae), was developed and tested. Orchard meadows as stable habitats were selected as spatial matrix and conventional insect traps and non-invasive approaches like eDNA analysis and automated monitoring were used in an effort to provide reliable long-term data at low cost. Data from four years of hoverfly sampling as well as some lessons learned are presented in this paper.