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

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.