Coastal biodiversity and introduced species in Arctic Norway

Metabarcoding of 32 sediment samples from Kongsfjorden, Norway, identified more than 150 taxa from two areas of the genome (gene CO1 and 18S DNA). From these, one potential alien species, the tunicate Botrylloides violaceus was identified. The potential negative impacts of B. violaceus and other invasive colonial tunicates are significant and increased temperatures in the future are likely to enhance vegetative growth where it has established. The threat suggested by impacts in other invasion areas indicates that targeted action to prevent B. violaceus from entering Svalbard should be initiated. Knowledge of the biodiversity around Svalbard is more sparse than for the more available marine areas. Some species might have been overlooked in the past and received a status as invasive when they are possibly native. This results show that metabarcoding has great potential for monitoring the presence of alien species in environmental samples in the Arctic and could be used to establish a baseline. CBMP- coast expert groups from other arctic areas reports on ongoing initiatives to identify arctic aliens to have a proper baseline whereby further biodiversity monitoring effort can be performed.