The re-appearance of the Mytilus spp. complex in Svalbard, Arctic, during the Holocene: The case for an arrival by anthropogenic flotsam

• Published in: Global and planetary change 2021-07, Vol.202, p.103502, Article 103502
• Main Authors: Kotwicki, L., Weslawski, J.M., Włodarska-Kowalczuk, M., Mazurkiewicz, M., Wenne, R., Zbawicka, M., Minchin, D., Olenin, S.
• Format: Article
• Language: English
• Subjects: Arctic; Genetics; Global change; Mytilus spp; Plastic litter; Re-introduction; Vectors
• ISSN: 0921-8181; 1872-6364
• DOI: 10.1016/j.gloplacha.2021.103502

The blue mussel Mytilus spp. complex has re-appeared in the high Arctic in Svalbard after a thousand years, with the first recent indication of its appearance in 2002 at the mouth of Isfjorden on the west coast. We examine its genetic affinity to selected North Atlantic populations and the modes of spread that may be responsible for its recent re-colonisation. We record here its distribution on Svalbard archipelago along the north-western coastline and within Isfjorden collected over a seven years period. We record for the first time the intertidal occurrence that includes a presence close to a glacier front. Genetic composition of mussels Mytilus spp. from different Svalbard locations reveal similarities mainly with populations of M. edulis, M. trossulus and their hybrid from Western Europe, Faroe Island, Scotland and Norway. The re-introduction to Svalbard most probably involved shipping and natural or anthropogenic flotsam. It seems that a new transport vector - large plastic debris - plays a significant role in this process. •The recent reappearance of Mytilus in the Arctic is a fact.•A massive plastic litter drift as a transportation platform.•“Island biogeography” theory as an explanation for the spread of the blue mussel.