Data from: Environmental DNA metabarcoding reliably recovers arthropod interactions which are frequently observed by video recordings of flowers

Environmental DNA (eDNA) metabarcoding promises to be a cost- and
time-efficient monitoring tool to detect interactions of arthropods with
plants. However, observation-based verification of the eDNA derived data
is still required to confirm whether the arthropods indeed previously
interacted with the plant. Here we conducted a comparative analysis of the
performance of eDNA metabarcoding and video camera observations to detect
arthropod communities associated with sunflowers (Helianthus annuus, L.).
We compared the taxonomic composition, interaction type, and diversity by
testing for an effect of arthropod interaction time and occupancy on
successful taxon recovery by eDNA. We also tested if pre-washing of the
flowers successfully removed eDNA deposition from before the video camera
recording, thus enabling a reset of the community for standardized
monitoring. We find that eDNA and video camera observations recovered
distinct communities, with about a quarter of the arthropod families
overlapping. However, the overlapping taxa comprised ~90% of the
interactions observed by the video camera. Interestingly, eDNA
metabarcoding recovered more unique families than the video cameras, but
approx. two-third of those unique observations were rare species. The
eDNA-derived families were biased towards plant sap-suckers, showing that
such species may deposit more eDNA than e.g. transient pollinators. We
also find that pre-washing of the flower heads did not suffice to remove
all eDNA traces, suggesting that eDNA on plants may be more temporally
stable than previously thought. Our work highlights the great potential of
eDNA as a tool to detect plant-arthropod interactions, particularly for
specialized and frequently interacting taxa.