Aerial colonization of high Arctic islands by invertebrates: The diamondback moth Plutella xylostella (Lepidoptera: Yponomeutidae) as a potential indicator species

Abstract

The restricted animal communities of the high Arctic islands are due, in part, to extreme geographical isolation. Migration via wind currents is one mechanism by which invasion of new species may occur. Here, we describe immigration of the non-resident migratory moth, Plutella xylostella, into Svalbard during 2000. This was associated with a warm south-easterly air mass that crossed from W. Russia: moths appear to have covered the 800 km to Svalbard in under 48 h, flying at an altitude between 500 and 1500 m. These events thus provide a case study for wind-dispersed movements of invertebrates to high Arctic regions. Climate change scenarios predict increased frequency of such air masses and also of the warm dry weather associated with increased aerial insect transport. The general factors determining successful colonization of the high Arctic by wind-dispersed animals are discussed, using P. xylostella as a model species whose important life history and physiological attributes are well known.