Individual-based model of population dynamics in a sea urchin of the Kerguelen Plateau (Southern Ocean), Abatus cordatus, under changing environmental conditions

• Published in: Ecological Modelling
• Main Authors: Arnould-Pétré, Margot, Guillaumot, Charlène, Danis, Bruno, Féral, Jean-Pierre, Saucède, Thomas
• Other Authors: Biogéosciences UMR 6282 (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Biologie Marine, Université libre de Bruxelles (ULB), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement IRD : UMR237-Centre National de la Recherche Scientifique (CNRS), IPEV programme PROTEKER (No.1044), French LTER Zone ATelier Antarctique (ZATA), Belgian Science Policy Office (BELSPO, contract n◦BR/132/A1/vERSO), contribution no. 13 to the “Refugia and Ecosystem Tolerance in the Southern Ocean” project (RECTO; BR/154/A1/RECTO) funded by the Belgian Science Policy Office (BELSPO), French Foundation for Research on Biodiversity and its partners (FRB - www.fondationbiodiversite.fr), “Fonds pour la formation `a la Recherche dans l’Industrie et l’Agriculture” (FRIA) and « Bourse fondation de la mer », IPEV programme PROTEKER (No.1044)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: Kerguelen; Climate change; Model sensitivity; Endemic echinoderm; Dynamic energy budget; Individual-based model; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Antarctic; Indian; Kerguelen Islands; Southern Ocean; Antarc*
• Online Access: https://hal.archives-ouvertes.fr/hal-03018516; https://doi.org/10.1016/j.ecolmodel.2020.109352

International audience The Kerguelen Islands are part of the French Southern Territories, located at the limit of the Indian and Southern oceans. They are highly impacted by climate change, and coastal marine areas are particularly at risk. Assessing the responses of species and populations to environmental change is challenging in such areas for which ecological modelling can constitute a helpful approach. In the present work, a DEB-IBM model (Dynamic Energy Budget – Individual-Based Model) was generated to simulate and predict population dynamics in an endemic and common benthic species of shallow marine habitats of the Kerguelen Islands, the sea urchin Abatus cordatus. The model relies on a dynamic energy budget model (DEB) developed at the individual level. Upscaled to anindividual-based population model (IBM), it then enables to model population dynamics through time as a result of individual physiological responses to environmental variations. The model was successfully built for a reference site to simulate the response of populations to variations in food resources and temperature. Then, it was implemented to model population dynamics at other sites and for the different IPCC climate change scenarios RCP 2.6 and 8.5. Under present-day conditions, models predict a more determinant effect of food resources on population densities, and on juvenile densities in particular, relative to temperature. In contrast, simulations predict a sharp decline in population densities under conditions of IPCC scenarios RCP 2.6 and RCP 8.5 with a determinant effect of water warming leading to the extinction of most vulnerable populations after a 30-year simulation time due to high mortality levels associated with peaks of high temperatures. Such a dynamic model is here applied for the first time to a Southern Ocean benthic and brooding species and offers interesting prospects for Antarctic and sub-Antarctic biodiversity research. It could constitute a useful tool to support conservation studies in these remote regions ...