Economic impacts of invasive alien plants in France
Invasive alien species can have an array of negative impacts including direct impacts on biodiversity, habitats and ecosystem services. In addition, invasive alien species can have high economic costs which can be associated with damage and loss (e.g. reduced crop yield, damage to infrastructure) and/or prevention and management (e.g. education, biosecurity, control and eradication). France has a long history of global trade and tourism which can lead to the entry of invasive alien species. Data on observed and potential costs of invasive alien species in France were collected from literature searches and targeted data collection from experts and stakeholders. From a list of 14 of the costliest invasive alien species in France, six entries were invasive alien plants: Ambrosia artemisiifolia (Asteraceae – EPPO List of Invasive Alien Plants), A. polystachya (Asteraceae), Baccharis halimifolia (Asteraceae – EPPO A2), Lagarosiphon major (Hydrocharitaceae - EPPO List of Invasive Alien Plants), Ludwigia spp. and Reynoutria (Fallopia) spp. Costs related to invasive alien plants can vary depending on the species. For example, for A. artemisiifolia much of the associated costs (estimated to be over EUR 500 million between 1993-2018 for mainland France and the French overseas territories) are related to the impact the species can have on human health. The pollen of A. artemisiifolia can cause allergic reactions in humans, e.g. pollinosis (hay fever). Medical care costs will significantly rise in France if mitigation measures aimed at limiting the proliferation of A. artemisiifolia are not further increased. For L. major, the majority of the estimated costs (almost EUR 1.5 million between 1993-2018 for mainland France and the French overseas territories) are due to management costs, the removal of the species from waterbodies using specialized mechanical equipment is expensive.
Sources
Renault D, Manfrini E, Leroy B, Diagne C, Ballesteros-Mejia L, Angulo E, Courchamp F (2021) Biological invasions in France: Alarming costs and even more alarming knowledge gaps. In: Zenni RD, McDermott S, García-Berthou E, Essl F (Eds) The economic costs of biological invasions around the world. NeoBiota 67, 191–224. https://doi.org/10.3897/neobiota.67.59134