Crinoid beds of Leptometra phalangium (Müller, 1841) have been identified as sensitive habitats by the General Fisheries Commission for the Mediterranean (GFCM) due to their high vulnerability to bottom trawl fisheries. Poorly resilient to physical damage, L. phalangium has been listed as a potential indicator of Vulnerable Marine Ecosystems (VMEs) in the Mediterranean Sea. If fishing activities represent the main cause of habitat destruction for this species, the ongoing changes in climate conditions may rapidly exacerbate the process. In this study, we developed an ensemble Species Distribution Modeling framework to predict the potential habitat of L. phalangium for present-days in the Mediterranean Sea, and used the model to infer potential changes in its spatial distribution by 2050 under two different climate scenarios (IPCC Representative Concentration Pathways RCP2.6 and RCP8.5). True presence-absence records were used and correlated to a parsimonious set of environmental predictors considered as important drivers of benthic species distribution. In present conditions, L. phalangium seems to be widely distributed along the continental slopes of the western and central Mediterranean. This crinoid is often described as confined to the continental shelf-break (100–200 m), but our results show that it can be found over a wider depth range, between 100 and 500 m. Our predictions obtained for the mid-21st century indicate an important habitat loss for L. phalangium under future climate conditions, mainly in the central and southern basins. Declines of 50 to 70 % in its suitable habitat were predicted under RCP2.6 and RCP8.5 compared to present-day predictions. Climate refugia (i.e., areas where environmental conditions remain suitable for the species in the future) were restricted to the northwestern basin (e.g., Gulf of Lion, the Catalan Sea, the Balearic Sea, Ligurian Sea) and in the southern Adriatic Sea. Provided by a robust statistical framework, climate refugia predictions, along with uncertainty assessments, must support the identification of priority areas for the conservation of VME indicator species by governmental bodies and regional management organizations.

中文翻译：

---

气候变化情景下易危甲壳类 Leptometra phalangium 的栖息地变化


Leptometra phalangium （Müller， 1841） 的甲壳类海床已被地中海渔业总委员会 （GFCM） 确定为敏感栖息地，因为它们对底拖网渔业的高度脆弱性。L. phalangium 对物理损伤的抵抗力差，已被列为地中海脆弱海洋生态系统 （VME） 的潜在指标。如果捕鱼活动是该物种栖息地破坏的主要原因，那么气候条件的持续变化可能会迅速加剧这一过程。在这项研究中，我们开发了一个集合物种分布建模框架来预测当今地中海 L. phalangium 的潜在栖息地，并使用该模型推断在两种不同气候情景 （IPCC 代表性浓度途径 RCP2.6 和 RCP8.5） 下到 2050 年其空间分布的潜在变化。使用了真实的存在-不存在记录，并与一组被认为是底栖物种分布重要驱动因素的简洁环境预测因子相关联。在目前的情况下，L. phalangium 似乎广泛分布在地中海西部和中部的大陆斜坡上。这种甲壳类动物通常被描述为局限于大陆架断裂（100-200 m），但我们的结果显示，它可以在 100 到 500 m 之间的更宽深度范围内找到。我们对 21 世纪中叶的预测表明，在未来气候条件下，主要是在中部和南部盆地，L. phalangium 将失去重要的栖息地。与目前的预测相比，RCP2.6 和 RCP8.5 预测其适宜栖息地的下降幅度为 50% 至 70%。气候避难所（即，环境条件在未来仍然适合该物种的区域）仅限于西北盆地（例如，狮子湾、加泰罗尼亚海、巴利阿里海、利古里亚海）和亚得里亚海南部。在强大的统计框架下，气候避难所预测以及不确定性评估必须支持政府机构和区域管理组织确定保护 VME 指标物种的优先区域。