Les articles de Fabien Verniest

Exposure of wetlands important for nonbreeding waterbirds to sea-level rise in the Mediterranean

de Fabien Verniest, Thomas Galewski, Olivier Boutron, Laura Dami, Pierre Defos du Rau, Anis Guelmami, Romain Julliard, Nadège Popoff, Marie Suet, Loic Willm, et al.
In Conservation Biology, 2024 (May, 2024), e14288
En ligne : onlinelibrary.wiley.com[...]

Sea-level rise (SLR) is expected to cause major changes to coastal wetlands, which are among the world's most vulnerable ecosystems and are critical for nonbreeding waterbirds. Because strategies for adaptation to SLR, such as nature-based solutions and designation of protected areas, can locally reduce the negative effects of coastal flooding under SLR on coastal wetlands, it is crucial to prioritize adaptation efforts, especially for wetlands of international importance for biodiversity. We assessed the exposure of coastal wetlands important for nonbreeding waterbirds to projected SLR along the Mediterranean coasts of 8 countries by modeling future coastal flooding under 7 scenarios of SLR by 2100 (from 44- to 161-cm rise) with a static inundation approach. Exposure to coastal flooding under future SLR was assessed for 938 Mediterranean coastal sites (≤30 km from the coastline) where 145 species of nonbreeding birds were monitored as part of the International Waterbird Census and for which the monitoring area was delineated by a polygon (64.3% of the coastal sites monitored in the Mediterranean region). Thirty-four percent of sites were threatened by future SLR, even under the most optimistic scenarios. Protected study sites and study sites of international importance for waterbirds were, respectively, 1.5 and 2 times more exposed to SLR than the other sites under the most optimistic scenario. Accordingly, we advocate for the development of a prioritization scheme to be applied to these wetlands for the implementation of strategies for adaptation to SLR to anticipate the effects of coastal flooding. Our study provides major guidance for conservation planning under global change in several countries of the Mediterranean region.

Anticipating the effects of climate warming and natural habitat conversion on waterbird communities to address protection gaps

de Fabien Verniest, Isabelle Le Viol, Romain Julliard, Laura Dami, Anis Guelmami, Marie Suet, Wed Abdou, Hichem Azafzaf, Nadjiba Bendjedda, Taulant Bino, et al.
In Biological Conservation, 279 (March, 2023), 10
En ligne : www.sciencedirect.com[...]

Thermal adjustment of waterbird communities to climate warming is crucial but hampered by natural habitat conversion, increasing their climatic debt. As it is, in contrast, facilitated in protected areas, assessing the adequacy of the current protected areas network with respect to future climate and land-use changes and identifying priority sites to protect is of major importance. In this study, we assess the thermal adjustment limitations that non-breeding waterbird communities might experience by the end of the 21st century in the Mediterranean region to highlight priorities for wetland protection. Priorities were set by combining the exposure of waterbird communities to natural habitat conversion and climate warming with their thermal specialization. The latter was calculated using winter abundance data of 151 species from 2932 sites of the International Waterbird Census in 21 Mediterranean countries. Exposure was assessed using future projections of temperature and land-use under four CMIP6 scenarios (SSP1–2.6, SSP2–4.5, SSP3–7.0, and SSP5–8.5). We found that strictly protected areas are located in wetlands whose waterbird communities, without protection, would likely experience high limitations in thermal adjustment in the coming decades. This highlights that the location of existing protected areas may effectively support the thermal adjustment of waterbird communities to future climate warming. However, 490 sites considered at risk lack protection, including 32 sites of international importance for waterbirds, stressing the need to strengthen the protected areas network in these sites in priority. Our study provides important guidance for conservation planning in the Mediterranean region to support waterbird responses to climate change. /
Dans notre étude, nous avons évalué les difficultés potentielles des communautés d’oiseaux d’eau hivernants à ajuster leur composition aux futurs changements de température en combinant la spécialisation thermique de la communauté avec deux métriques d’exposition à l’augmentation future des températures hivernales et à la perte future d’habitats naturels à l’horizon 2090 selon quatre scénarios futurs différents. Nous avons ainsi constaté que les aires protégées, et notamment celles strictement protégées, sont situées dans des zones humides dont les communautés d'oiseaux d'eau, sans protection, auraient probablement connu de fortes difficultés d'ajustement thermique au cours des prochaines décennies. Cela met en évidence la pertinence de l'emplacement des aires protégées existantes qui pourront faciliter de manière efficace l'adaptation thermique des communautés d'oiseaux d'eau au réchauffement climatique futur. Cependant, nous avons également identifié 490 sites à risque et ne bénéficiant d'aucun statut de protection, dont 32 sites d'importance internationale pour les oiseaux d'eau, ce qui souligne la nécessité de renforcer le réseau d'aires protégées méditerranéen dans ces sites en priorité.

Anticiper les changements climatiques pour protéger la biodiversité des zones humides

de Fabien Verniest, Isabelle Le Viol
In The Conversation, 207483 (Juillet, 2023)
En ligne : theconversation.com[...]

Les aires protégées jouent un rôle clé dans la conservation de la biodiversité. Alors que de nombreuses devraient voir le jour d’ici à 2030 suite à l’accord de Kunming-Montréal, il est essentiel de penser leur emplacement afin d’anticiper au mieux les futures menaces pour la biodiversité.
Ainsi, en Méditerranée, de très nombreuses zones humides menacées par d’importants changements futurs de climat et d’usage des terres ne sont toujours pas protégées. Cette situation pourrait compromettre l’adaptation au changement climatique des oiseaux qu’elles abritent.

Coupling future climate and land-use projections reveals where to strengthen the protection of Mediterranean Key Biodiversity Areas

de Fabien Verniest, Thomas Galewski, Romain Julliard, Anis Guelmami, Isabelle Le Viol
In Conservation Science and Practice, Online (October, 2022), 17
En ligne : onlinelibrary.wiley.com[...]

Identifying sites that are both important for biodiversity and likely to be heavily affected by anthropogenic pressures in the future is crucial to settle priorities in the implementation of conservation measures, such as the designation of new protected areas. Although assessing the exposure of terrestrial Key Biodiversity Areas to global change would support such identification, it has never been performed to our knowledge. In addition, previous exposure assessments have been limited to few metrics of climate change and have not considered other global change components. Here, we assess the extent to which terrestrial (including inland water) Key Biodiversity Areas are exposed to future climate change and land-use modifications in 29 countries of the Mediterranean region, and identify countries where additional protection efforts are most needed. To this end, we calculated two local and two regional exposure metrics using projections of climate and land-use for late 21st century under four scenarios that were used in the sixth assessment report of the Intergovernmental Panel on Climate Change (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5). These four exposure metrics were subsequently combined into an exposure index ranking sites from least to most exposed to climate and land-use changes. We highlight that the most exposed non-protected Key Biodiversity Areas are located in countries where the protection of this network is lowest (i.e., high number and percentage of non-protected sites). We also found that Key Biodiversity Areas were overall more exposed than the rest of the study zone and that the sites most in need of conservation actions were similar across future scenarios. Our study reinforces the pressing necessity to strengthen and extend conservation measures in Mediterranean Key Biodiversity Areas, especially in Middle-East and Maghreb countries whose Key Biodiversity Areas are both at risk to be strongly affected by anthropogenic pressures and insufficiently protected.

Gap analysis of the Ramsar site network at 50: over 150 important Mediterranean sites for wintering waterbirds omitted

de Nadège Popoff, Elie Gaget, Arnaud Béchet, Laura Dami, Pierre Defos Du Rau, Ilse Geijzendorffer, Anis Guelmami, Jean-Yves Mondain-Monval, Christian Perennou, Marie Suet, et al.
In Biodiversity and conservation, 30 (July, 2021), 19
En ligne : link.springer.com[...]

The Mediterranean Basin is a biodiversity hotspot. Wetlands make a key contribution to this status, but many of them remain outside the Ramsar network fifty years after the establishment of the Ramsar Convention. Here we evaluate the extent to which the Mediterranean Ramsar network covers wetlands of international importance for wintering waterbirds using the Ramsar Convention criteria 2 (species of conservation concern), 5 (> 20,000 waterbirds) and 6 (1% of a population). These criteria were applied to 4186 sites in 24 Mediterranean countries using counts of 145 wintering waterbird species from 1991 to 2017. We identified 161 sites of international importance for waterbirds that have not yet been declared as Ramsar sites, which could be added to the 180 current Mediterranean Ramsar sites established based on waterbird criteria (criteria 5 and/or 6). Among these sites, a subset of 32 very important sites reached double the required level for at least one criterion and 95 were not protected by any site conservation status. Coastal wetlands represented half of the Ramsar gap for waterbirds. We identified that an additional 1218 monitored sites could be provisionally considered as internationally important and thus require more survey efforts to assess their status. This study highlights a lack of participation of the Mediterranean countries to build the Ramsar network for wetland protection. Our results should help policymakers and managers to prioritize future Ramsar site designation, notably in the Middle East and Western European region where important gaps were identified.