The human-mediated movement of species around the world has added several layers of complexity to the management of ecosystems. Once alien species are established in a new region they are extremely difficult or impossible to eradicate, and control is expensive and often ineffective.
Following Charles Elton’s pioneering work, invasion ecology has grown into a mainstream research field focusing on the patterns and processes of human-mediated translocation of alien organisms. As probably the most iconic taxa in conservation, birds provide an ideal natural experiment to test many theories and hypotheses in invasion ecology.
Most people think of Antarctica as completely covered in ice. Ice-free areas cover only 0.4 % of the total continental area and until relatively recently it was thought that most were barren and largely devoid of life.
It may no longer make economic or environmental sense to pursue forestry endeavours using conifers in the Western Cape. If local plantations are to be maintained, invasive pine trees will continue to spread, the Cape’s water supply will continue to dwindle and the unique natural diversity of the fynbos region will be changed forever.
Antarctica is regarded as one of the most pristine environments on Earth. There is, however, a growing concern that the icy continent is being threatened by alien species that are accidentally being brought to the continent in the luggage of tourists and scientists.