Abstract 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 an individual-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 where access and bio-monitoring represent challenging issues.

中文翻译：

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在不断变化的环境条件下，基于个体的凯尔盖朗高原（南大洋）海胆种群动态模型 Abatus cordatus

摘要 凯尔盖朗群岛是法属南部领地的一部分，位于印度洋和南洋的边界。它们受气候变化的影响很大，沿海海域尤其处于危险之中。在生态建模可以构成有用方法的这些领域，评估物种和种群对环境变化的反应具有挑战性。在目前的工作中，生成了 DEB-IBM 模型（动态能量预算 - 基于个体的模型）来模拟和预测凯尔盖朗群岛浅海栖息地的地方性和常见底栖物种海胆 Abatus cordatus 的种群动态。该模型依赖于在个人层面开发的动态能量预算模型 (DEB)。升级到基于个人的人口模型 (IBM)，然后，由于个体对环境变化的生理反应，它可以模拟随时间变化的种群动态。该模型已成功用于参考地点，以模拟人口对食物资源和温度变化的反应。然后，它被用于模拟其他地点的人口动态以及不同的 IPCC 气候变化情景 RCP 2.6 和 8.5。在当前条件下，模型预测食物资源对人口密度，特别是对幼鱼密度的决定性影响，与温度有关。相比之下，模拟预测在 IPCC 情景 RCP 2.6 和 RCP 8 的条件下人口密度会急剧下降。5 具有决定性影响，由于与高温峰值相关的高死亡率，在 30 年的模拟时间后，水变暖导致最脆弱人群灭绝。这种动态模型首次应用于南大洋底栖和育雏物种，为南极和亚南极生物多样性研究提供了有趣的前景。它可以构成一个有用的工具来支持这些偏远地区的保护研究，在这些偏远地区，访问和生物监测是具有挑战性的问题。