Metabarcoding improves detection of eukaryotes from early biofouling communities: implications for pest monitoring and pathway management

In this experimental study the patterns in early marine biofouling communities and possibleimplications for surveillance and environmental management were explored using metabarcoding,viz. 18S ribosomal RNA gene barcoding in combination with high-throughput sequencing. Thecommunity structure of eukaryotic assemblages and the patterns of initial succession were assessedfrom settlement plates deployed in a busy port for one, five and 15 days. The metabarcoding resultswere verified with traditional morphological identification of taxa from selected experimentalplates. Metabarcoding analysis identified > 400 taxa at a comparatively low taxonomic level andmorphological analysis resulted in the detection of 25 taxa at varying levels of resolution. Despitethe differences in resolution, data from both methods were consistent at high taxonomic levels andsimilar patterns in community shifts were observed. A high percentage of sequences belonging togenera known to contain non-indigenous species (NIS) were detected after exposure for only oneday