Have you ever considered that the one of the most diverse places on earth can be directly under your feet?

When we walk, our shoes pick up various seen and unseen organisms.  Many of us walking through a field or park may be stepping on and carrying seeds from various plants. Seeds blow in the wind and also creep into the crevices of our clothes and bags.  As carriers, we then transport them to new areas, making each of us essentially a seed planter. At first glance this seems like a nice job description.  However, the problem lies in the fact that seeds can find themselves in uncharted territory.

In Antarctica, the landscape has changed dramatically in recent years. As the climate is warming, the Antarctic Peninsula is uncovering more areas that are “ice-free”.  These areas are particularly vulnerable as alien species have flourished here.  This is in large part due to the transfer of seeds from visitors to the continent.  Environment correspondent Richard Black of BBC News wrote in his article, “Alien invaders threaten Antarctic fringes,” that an average of 9.5 seeds are carried by each visitor to this continent.  Many of these seeds, coming from as far as the North hemisphere, can survive and thrive in the warmer areas of the continent, potentially causing a major ecological shift.

Some invasive species, such as the grass species Poa annua, have taken over some of the sub-Antarctic islands such as South Georgia.  It is thought that scientists brought this seed to parts of Antarctica due to the proximity of Poa annua grasslands to the different science research stations.

South Georgia has an even bigger problem. Due to whaling expeditions, rats have infested grasslands and have become the dominant predatory species. Perhaps this island is a microcosm of what is to come in the great White Continent.  Covered with rats.

What is the solution? Well, we can’t completely prevent all unwanted seed from arriving in Antarctica, no matter how hard we try. However, organizations are trying to help reduce the amount of alien seed arriving and surviving on the continent. The International Association of Antarctic Tour Operators (IAATO) has been working diligently to ensure that visitors are “seed-free” and some science organizations have created guidelines for checking of vehicles, bags and clothes for seeds. Perhaps extra surveillance of visitors will ensure that Antarctica never becomes a vast grassland.

For more information:

http://www.bbc.co.uk/news/science-environment-17258799

http://blog.earth-touch.com/nature-news/south-georgias-rats-get-the-death-sentence/