Data from: Dr. D Bergstrom, Australian Antarctic Division, redrawn with permission
Example: An Alien on sub-Antarctic Heard Island
Annual Poa (Poa annua), is a grass, native to Europe. The grass has been unintentionally distributed by man to many other places on the globe and has now a cosmopolitan distribution. It has been found on many sub-Antarctic islands. On Marion Island the species is spreading vigorously and is outcompeting the native vegetation. On Heard Island it was initially recorded in 1987 in two recently deglaciated areas not previously exposed to human visitation, while at the same time being absent from known sites of past human habitation. Consequently, it is thought to have been naturally introduced, possibly from the Îles Kerguelen where it is widespread.
(Photo by Kate Kiefer, Australian Antarctic Division)