Pre-assessments of plant conservation status in islands: the case of French Overseas Territories

• Published in: Biodiversity and Conservation
• Main Authors: Véron, Simon, Bernard, Arthur, Lebreton, Elise, Rodrigues-Vaz, Carlos, Durand, M, Procopio, L, Hélion, M, Gayot, M, Viscardi, Guillaume, Krupnick, G, Carrington, C, Boullet, Vincent, Mallet, Bertrand, Dimassi, Abassi, Pailler, Thierry, Hivert, Jean, Lebouvier, Marc, Agnola, Pierre, Bruy, David, Gateblé, Gildas, Lannuzel, Guillaume, Meyer, Shankar, Gargominy, Olivier, Gigot, Guillaume, Invernon, Vanessa, Leblond, Sébastien, Pignal, Marc, Tercerie, Sandrine, Muller, Serge, Rouhan, Germinal
• Other Authors: Institut de Systématique, Evolution, Biodiversité (ISYEB ), Muséum national d'Histoire naturelle (MNHN)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD France-Sud )-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université de Montpellier (UM), Herbier de Nouvelle-Calédonie (Herbier NOU), Institut de Recherche pour le Développement (IRD Nouvelle-Calédonie ), Office Français de la Biodiversité (OFB), Ministère des Outre-mer, Muséum national d’Histoire naturelle (MNHN)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2023
• Subjects: Red List; Pre-assessments; Islands; Tracheophytes; French overseas territories; Endemics; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDE.MCG]Environmental Sciences/Global Changes; [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics; Antarctic; Antarc*
• Online Access: https://hal-mnhn.archives-ouvertes.fr/mnhn-03952485; https://hal-mnhn.archives-ouvertes.fr/mnhn-03952485/document; https://hal-mnhn.archives-ouvertes.fr/mnhn-03952485/file/Paper%20pre-assessment%20_%20HAL.pdf; https://doi.org/10.1007/s10531-023-02544-8

International audience Assessment methods have been developed to estimate a preliminary conservation status for species and subsequently to facilitate the building of Red Lists. Such pre-assessment methods could be particularly useful in the French Overseas Territories (FOTs) where Red Lists tend to be outdated or absent and where a high number of endemic species face detrimental anthropogenic pressures. We first aimed to conduct a preliminary assessment (hereafter, pre-assessment) of the conservation status of endemic plants from Guadeloupe, Martinique, Réunion, Mayotte, French sub-Antarctic islands, New Caledonia, and Scattered Islands. We then compared the various methods used in conducting the pre-assessment and discussed ways to adapt these methods to small territories. We compiled occurrence data of endemic species identified thanks to a previous taxonomic work and pre-assessed their conservation status under Red List criteria A and B and the use of a Random Forest algorithm. We then measured the accuracy, specificity, and sensitivity of each method based on existing Red Lists. The Random Forest algorithm and a method based on range-size performed best at correctly attributing conservation status. Using these pre-assessment methods, we estimated that up to 60% of the endemic flora of the FOTs is potentially threatened. Range restriction but also anthropogenic pressures were key factors that explained these risks. Pre-assessment methods are useful tools to get a first measure of species conservation status. These methods should be adapted to the territories considered and their conservation issues in order to reach a good performance.