Conférence de Peter CONVEY (British Antarctic Survey, Cambridge)

 Olivier Troccaz    07/02/2011 : 09:30


Le lundi 7 février, à 10h30, salle de conférences du Caren, campus de Beaulieu, UR1.

Le lundi 7 février, à 10h30, salle de conférences du Caren, campus de Beaulieu, UR1. Invasions in the Antarctic Abstract : Ice-free habitats on land in Antarctica and the sub-Antarctic are islands surrounded by hostile ice and ocean. Terrestrial ecosystems are extremely isolated, and have developed unique and striking features. True terrestrial vertebrates are generally absent, meaning that most trophic webs consist only of invertebrates. Ecosystem structure is generally simplified, with few true native herbivores or predators present, and the predators in particular having very limited impact on their prey species. Over the last two centuries human activities have led to the accidental introduction and establishment on land of many non-indigenous species of vertebrate, invertebrate and plant, particularly to the ecosystems of the sub-Antarctic islands. These introductions have encompassed a range of trophic functions, some of which are poorly or not represented in indigenous ecosystems, in some cases leading to drastic alterations in ecosystem structure and function. A smaller number of introductions are already apparent in the maritime Antarctic, although the sub-Antarctic provides a direct warning of the likely trajectories of these and any future establishment events. This presentation will give an overview of the impacts of non-indigenous biota in Antarctic ecosystems to date, and their implications in a future where these ecosystems are also faced by some of the most rapid rates of environmental change on the planet. Contact : Peter CONVEY