Affiliation: | (1) Laboratoire Biodiversité et Fonctionnement des écosystèmes, Université de Metz, UFR SciFA, Campus Bridoux, Av. du Gén. Delestraint, 57070 Metz, France;(2) Equipe Ecologie Evolutive, UMR CNRS 5561 Biogéosciences, Université de Bourgogne, 6 boulevard Gabriel, 21000 Dijon, France;(3) Muséum National d’Histoire Naturelle, Département Milieux et Peuplements Aquatiques, UMR CNRS-UPMC-MNHN BOME 5178, 55 rue Buffon, 75005 Paris, France |
Abstract: | Freshwater biodiversity is threatened by several mechanisms, of which the introduction of non-indigenous species and habitat alteration are the two most important. Exotic species act at various levels of organisation of macroinvertebrate communities, and are involved in different processes mediating their impacts on biodiversity, such as habitat modification or negative interactions with autochthonous fauna. The present work gives a list of the 43 French freshwater non-indigenous species, which represent 1.2% of the French freshwater macroinvertebrates. We provide their geographic origins, their distributions among zoological units by comparison with the native fauna and their functional characteristics according to a recent typology based on bio/ecological traits. An exponential trend of the cumulated number of non-indigenous species was evidenced, with a clumping of invaders within crustaceans and molluscs. Donor areas of non-indigenous species are in majority European, and the Ponto-Caspian basin is identified as the principal one. This pattern could be explained by a spread along waterways but its origin lies in a process of recolonisation of defaunated areas following several episodes of glaciation/deglaciation in Western Europe during the last 80,000 years. Finally, from a functional point of view, non-indigenous species exhibit a limited diversity, with two functional groups representing 80% of them. |