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.

蓝色贻贝Mytilus spp。一千年后，该综合体重新出现在斯瓦尔巴群岛的北极高地，最近的首次迹象是它于2002年出现在西海岸的伊斯菲约登河口。我们检查了其对选定北大西洋种群的遗传亲和力，以及可能对其近期重新定殖负责的传播方式。我们在这里记录了它在西北海岸线的斯瓦尔巴群岛上以及在伊斯菲约登内收集的长达七年时间的分布。我们第一次记录了潮间带的出现，其中包括靠近冰川前沿的存在。贻贝Mytilus spp的遗传组成。来自不同的斯瓦尔巴群岛的位置揭示出的相似性主要与毛蓝藻种群相似，trossulus及其杂种来自西欧，法罗岛，苏格兰和挪威。重新引入斯瓦尔巴群岛很可能涉及运输和天然或人为的漂浮物。似乎新的运输媒介-大塑料碎片-在此过程中起着重要作用。