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BACKGROUNDBlack rats, Rattus rattus, and mat-forming iceplants, Carpobrotus aff. acinaciformis and Carpobrotus edulis, are pervasive pests on Mediterranean islands. Their cumulative impacts on native biotas alter the functioning of island ecosystems and threaten biodiversity. A report is given here of the first attempt to eradicate both taxa from a protected nature reserve in south-eastern France (Bagaud Island). In order to minimise unwanted hazardous outcomes and produce scientific knowledge, the operations were embedded in a four-step strategy including initial site assessment, planning, restoration and monitoring. RESULTSTrapping, which resulted in the removal of 1923 rats in 21045 trap-nights, made it possible to eliminate a substantial proportion of the resident rat population and to reduce the amount of rodenticide delivered in the second stage of the operation. Forty tons of Carpobrotus spp. were manually uprooted from a total area of 18000 m(2); yet careful monitoring over a decade is still required to prevent germinations from the seed bank. CONCLUSIONTwo years after the beginning of the interventions, both eradication operations are still ongoing. Biosecurity measures have been implemented to reduce reinvasion risks of both taxa. With the long-term monitoring of various native plants and animals, Bagaud Island will become a reference study site for scientific purposes.

International audience; Landscape connectivity is generally considered to facilitate gene flow between populations. Hence, highly connected hedgerow networks are often thought to support higher gene flow than disconnected hedgerow networks or open landscapes. In order to test this hypothesis, we studied gene flow between Primula vulgaris populations at the landscape level. Our results indicated a strong spatial genetic autocorrelation that is significantly more pronounced in the dense and connected hedgerow network than in the open and disconnected ones up to 400 m. This was interpreted as a restriction to pollen dispersal due to hedgerow density and limited dispersal of seeds by ants. Thus spatial connectedness does not provide a high biological connectivity.