Biosecurity in Antarctica

Antarctica has an extremely harsh and unforgiving environment that excludes most life forms. The air temperature is below freezing most of the year and strong winds emphasise the extreme cold. There is also large variation in the hours of light and darkness throughout the year. It is not a hospitable environment for the survival of plant and animal species including humans. There is a limited amount of free running water and 98% of the continent is covered in ice1 . The conditions in the ocean are better than on the land. Although the conditions are cold, the ocean is abundant with life as the water is warmer than the air temperature2 . The water temperature remains comparatively constant year round. This is due to reduced wind effect as much of the ocean around Antarctica is covered by ice forming a protective layer. There are also large volumes of nutrients for species to feed on. Due to the limited ice-free areas in Antarctica the niches for plants and animals are limited. This is further hampered by the fact that some areas are more exposed to extreme weather conditions, further reducing available habitat. There are two plants that grow in Antarctica, Deschampsia antarctica (Antarctic grass) and Colobanthus quitensis (pearlwort) (McGonigal & Woodworth, 2002; Rubin, 2000). Due to better conditions on the Antarctic Peninsula these species are more common here than elsewhere in Antarctica3 . These species can tolerate the extreme conditions that are present on the continent and can still photosynthesise at freezing point (McGonigal & Woodworth, 2002)