Visitors to Antarctica unintentionally import alien species

07-03-2012   Seeds carried by visitors on their clothing, rucksacks and camera bags may be the cause of the introduction of non-indigenous plants to Antarctica that might pose a threat to natural biodiversity and the functioning of the Antarctic terrestrial ecosystems.

This is the outcome of a study by an international team of scientists that was published earlier this week in the American scientific journal PNAS. Eleven different research groups from 9 different countries worked together on this project. Ad Huiskes, working for the Centre for Estuarine and Marine Ecology, a division of the Netherlands Institute of Ecology (now Royal Netherlands Institute for Sea Research, NIOZ, Yerseke Division) was the head of logistics for this project. Niek Gremmen of Data Analyse Ecologie, an ecological consultancy, was the data analyst.

Steven L. Chown and his colleagues collected and identified over 2,600 plant seeds, that were found on clothes and luggage belonging to scientists and tourists on their way to Antarctica, and they established the origin of these seeds. This research project was conducted in the summer season of 2007-2008 (during the International Polar Year). On the basis of these data, the scientists estimated the risk that non-indigenous seeds would settle, using the scenarios suggested by the Intergovernmental Panel on Climate Change (IPCC).

Plant seeds were found on clothes and luggage of one third of the visitors examined. On average, visitors carried 10 seeds. In addition to the seeds, mosses, lichen and fern spores were found.

Various non-indigenous species have now settled in Antarctica, especially in the area on the western coast of the Antarctic Peninsula, an area with more climate change than anywhere else in the world.

The study also showed that visitors to Antarctica (about 40,000 during the summer season of 2007-2008) had collectively visited nearly all countries in the world, and quite a few of them had also visited Arctic regions and regions with high mountains. About half the seeds reaching Antarctica was from species that can grow in cold regions.

An elaborate risk assessment of non-indigenous species settling in Antarctica is part of the article, which also includes suggestions about how to prevent the import of seeds.

Article #11-19787: ‘Continent-wide risk assessment for the establishment of non-indigenous species in Antarctica’, First Author: Steven L. Chown, Centre for Invasion Biology, University of Stellenbosch, Stellenbosch, SOUTH AFRICA; phone: +2721-808-2385; e-mail: slchown@sun.ac.za

Photograph by Niek Gremmen.
Seeds from one of the samples taken from a visitor to Antarctica.