Résumé
Question: Transfers of fresh fruits and vegetables between countries via passengers or commercial trade enables insects such as Tephritidae (Diptera commonly named 'fruit flies') to colonize new areas, causing crop losses as well as displacement of indigenous species. Islands are very sensitive areas to alien species introductions, making application of import regulations important to protect local agriculture. In Réunion Island (Indian Ocean), 309 import pathways of fruits and vegetables have been identified using data registered between 2007 and 2012. The question, raised by the French Ministry of Agriculture to Anses (Agency for Food, Environmental and Occupational Health & Safety), was to rank the pathways representing a potential infestation risk by some of the 224 fruit flies species considered as the most threatening. Methods: Two methods were developed: an information system, gathering information collected in databases, websites and publications, helped to identify the potentially infested pathways. A decision support system enabled pathways ranking according to the fruit flies hierarchy established using Promethée multi-criteria methoda. Results: 55 risky import pathways were ranked, linked with potential infestation by 16 fruit fly species belonging to the genera Anastrepha, Bactrocera, Ceratitis, Dacus and Rhagoletis. Because of their high probability of entry and establishment, the threatening species would be, in order of importance, B. invadens, C. rosa (the African strain), B. dorsalis (separated from B. invadens), B. tryoni and D. vertebratus. The most risky pathways would be, in order of importance, fresh fruits from the genus Citrus, Prunus, as well as Cucumis melo and Cucumis sativus, all coming from South Africa, then Citrus imported from Madagascar and peaches from Zambiab. Conclusion: The ranking of pathways allowed by our method enables the customs risk manager to better define border management measures and to adapt the control of each pathway according to the threat linked to the fruit flies potentially conveyed. (Texte intégral)