Ant diversity on Bagaud Island wilderness area (Var, France), before the eradication of two major invasive taxa:Rattus rattus and Carpobrotus spp.

• Main Authors: Berville, Laurence, Passetti, Aurélie, Ponel, Philippe
• Other Authors: Institut de recherche sur la biologie de l'insecte UMR7261 (IRBI), Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement IRD : UMR237-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: French
• Published: HAL CCSD 2015
• Subjects: initial state; ecological restoration; insular ecosystem; biological inventory; ants; fourmis; inventaire biologique; écosystème insulaire; restauration écologique; état initial; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDV.BA.ZI]Life Sciences [q-bio]/Animal biology/Invertebrate Zoology; Argentine; Rattus rattus
• Online Access: https://hal.science/hal-03036820; https://hal.science/hal-03036820/document; https://hal.science/hal-03036820/file/2004b38acc167cd5db4bde02d0456e05.pdf

International audience Involuntary displacement of both fauna and flora species has become an important factor regard to the conservation of biodiversity problematics. As a matter of fact, invading species represent the mean driver of biodiversity loss in isolated and simplified biotopes, such as insular ecosystems. The latter constitute propitious study sites for an assessment of the environmental impacts of invasive taxa; hence many eradication programs have been conducted in order to restore island biodiversity. Nevertheless, post-eradication scientific studies are scarce; in particular those seeking to take into account both benefits and losses of arthropod biodiversity. Bagaud Island wilderness area is an integral nature reserve included in Port-Cros National Park (PNPC) located in Hyères archipelago in southern France. For conservation purpose, the PNPC initiated a ten-year ecological restoration program including the eradication of both Rattus rattus (black rat) and Carpobrotus spp. (iceplant), well known for their negative impacts on the Mediterranean fauna and flora. However, it is essential to provide detailed information on the initial state of the environment to assess the effectiveness of the proposed measures over time. Thus, between 2010 and 2012, the initial state of ant biodiversity has been estimated using several trapping methods in the different habitats. The full set of data of all field campaigns yielded a high number of individuals (8 077) and 28 taxa. In spite of its small size (59 ha), Bagaud Island hosts more than 11.9 % of the French myrmecofauna, on less than 0.001‰ of his territory. Notwithstanding an apparent environment simplicity in terms of resources it would therefore appear that the micro-habitat diversity of the island may explain this high ant diversity. The Argentine ant (Linepithema humile), an invasive species that occurs on the neighboring Port-Cros and Porquerolles Islands, has to date not been reported on Bagaud. Le déplacement involontaire d’espèces de plantes et ...