Invasive alien species are considered one of the most significant threats to the unique biodiversity of Antarctica and these aliens are hitching a ride on us! Steven Chown, from the Centre for Invasion Biology at Stellenbosch University and his research team estimated that 70,000 seeds are brought into the continent by tourists and scientists each year. In fact, Chown’s findings indicate that scientists are more to blame than the tourists, even though they should be most aware of the problems caused by invasive species.
Chown and his team collected the clothing, footwear, walking poles, day packs and even camera bags from 853 people, approximately 2% of the annual total number of visitors. Using vacuum cleaners the team collected material from the visitor’s belongings and counted, sorted and identified all plant seeds hitchhikers. Over the course of one year, 7,000 scientists inadvertently brought in around 39,000 seed hitchhikers, whilst over the same period 33,000 tourists imported are far more conservative 32,000 alien seeds.
“Scientists tend to have gear they use more than once and tend also to visit many natural sites” Chown explains. “Often tourists are issued with new outer gear for a visit or make only a single visit to Antarctica and have special gear for the trip”.
The seed hitchhikers were predominantly identified as known invasive species of other cold areas like the Arctic and the islands around Antarctica. By mapping the entry points for these seeds, and comparing this with the localised climates, Chown and his team produced a map of Antarctica that shows the Western Antarctica Peninsula is most at risk from these alien hitchhikers.
Chown does suggest some simple ways of reducing the numbers of future unwanted guests. “Take gear that’s new, and if this is not possible, then clean gear thoroughly. Vacuum clean the pockets, check Velcro very closely and remove seeds. Remove inner linings from camera bags and clean everything out. Wash walking poles, tripods and boots. Easy and very effective”.
Quotes taken from the Not Exactly Rocket Science acrticle