Éradication de mammifères introduits en milieux insulaires : Questions préalables et mise en application

Abstract

During the last five centuries, along with the reduction of biogeographic barriers, a great number of alien species were introduced by men, intentionally or not, in nearly all ecosystems throughout the world. Most of these introductions failed and a majority of the others didn't raise any problem. But some of them led to major economic losses and/or biological diversity reduction. The insular vegetal and animal communities are little diversified, often disharmonic, and characterized by an important rate of endemic species when compared with those of continental ecosystems. These communities are therefore particularly vulnerable to alien species. For these reasons and because of the small size of islands which allows experimental studies, most operations of eradication took place in this type of ecosystems since the 1960s, mammal species being the main target. This paper offers an approach to improve the decision and the technical implementation in view of the eradication of alien mammals on islands. These recommendations are founded on the experiences of brown rat eradication from ten Brittany Islands (1994-1996) and those of rabbit eradication from three islands of the Kerguelen Archipelago (1992-1999).