Biological Invasions

, Volume 14, Issue 3, pp 567–577 | Cite as

Humans introduce viable seeds to the Arctic on footwear

  • Chris Ware
  • Dana M. Bergstrom
  • Eike Müller
  • Inger Greve AlsosEmail author
Original Paper


Expanding visitation to Polar regions combined with climate warming increases the potential for alien species introduction and establishment. We quantified vascular plant propagule pressure associated with different groups of travelers to the high-Arctic archipelago of Svalbard, and evaluated the potential of introduced seeds to germinate under the most favorable average Svalbard soil temperature (10°C). We sampled the footwear of 259 travelers arriving by air to Svalbard during the summer of 2008, recording 1,019 seeds: a mean of 3.9 (±0.8) seeds per traveler. Assuming the seed influx is representative for the whole year, we estimate a yearly seed load of around 270,000 by this vector alone. Seeds of 53 species were identified from 17 families, with Poaceae having both highest diversity and number of seeds. Eight of the families identified are among those most invasive worldwide, while the majority of the species identified were non-native to Svalbard. The number of seeds was highest on footwear that had been used in forested and alpine areas in the 3 months prior to traveling to Svalbard, and increased with the amount of soil affixed to footwear. In total, 26% of the collected seeds germinated under simulated Svalbard conditions. Our results demonstrate high propagule transport through aviation to highly visited cold-climate regions and isolated islands is occurring. Alien species establishment is expected to increase with climate change, particularly in high latitude regions, making the need for regional management considerations a priority.


Alien Non-indigenous Dispersal Germination Human-mediated dispersal Propagule pressure 



We thank the many people who assisted in footwear sampling at the Svalbard airport, and the 259 participants who kindly gave up their shoes for cleaning after arrival. We would also like to thank the staff at the Svalbard Airport for allowing us to conduct the study on airport premises. Financial assistance for this project was received from the Svalbard Environmental Protection Fund. This project is closely aligned with the IPY Aliens in Antarctica Project. Finally, we wish to extend our thanks to three anonymous reviewers for their comments on the manuscript.


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Chris Ware
    • 1
  • Dana M. Bergstrom
    • 2
  • Eike Müller
    • 1
  • Inger Greve Alsos
    • 1
    • 3
    Email author
  1. 1.The University Centre in Svalbard (UNIS)LongyearbyenNorway
  2. 2.Australian Antarctic Division, Department of the Environment, Water, Heritage and the ArtsKingstonAustralia
  3. 3.Tromsø University MuseumTromsøNorway

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