Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel.
Morris Kahn Marine Research Station, The Leon H. Charney School of Marine Sciences, University of Haifa, Sdot Yam, Israel.
Sci Rep. 2021 Sep 13;11(1):18134. doi: 10.1038/s41598-021-97447-5.
Globally, species are migrating in an attempt to track optimal isotherms as climate change increasingly warms existing habitats. Stony corals are severely threatened by anthropogenic warming, which has resulted in repeated mass bleaching and mortality events. Since corals are sessile as adults and with a relatively old age of sexual maturity, they are slow to latitudinally migrate, but corals may also migrate vertically to deeper, cooler reefs. Herein we describe vertical migration of the Mediterranean coral Oculina patagonica from less than 10 m depth to > 30 m. We suggest that this range shift is a response to rapidly warming sea surface temperatures on the Israeli Mediterranean coastline. In contrast to the vast latitudinal distance required to track temperature change, this species has migrated deeper where summer water temperatures are up to 2 °C cooler. Comparisons of physiology, morphology, trophic position, symbiont type, and photochemistry between deep and shallow conspecifics revealed only a few depth-specific differences. At this study site, shallow colonies typically inhabit low light environments (caves, crevices) and have a facultative relationship with photosymbionts. We suggest that this existing phenotype aided colonization of the mesophotic zone. This observation highlights the potential for other marine species to vertically migrate.
全球范围内，物种为了追踪因气候变化而不断变暖的最佳等温线，正试图迁徙。石珊瑚受到人为变暖的严重威胁，这导致了珊瑚的多次大规模白化和死亡事件。由于珊瑚在成年后是固着的，而且性成熟的年龄相对较大，它们在纬度上迁移的速度较慢，但珊瑚也可能垂直迁移到更深、更冷的珊瑚礁。在此，我们描述了地中海珊瑚 Oculina patagonica 从不到 10 米的深度向 >30 米深处的垂直迁移。我们认为这种范围的转移是对以色列地中海沿岸快速变暖的海面温度的一种响应。与跟踪温度变化所需的巨大纬度距离相比，这种物种向更深的地方迁移，那里夏季水温低 2°C。对深海和浅海同种生物的生理学、形态学、营养位置、共生体类型和光化学的比较只揭示了少数深度特异性差异。在这个研究地点，浅海群体通常栖息在低光照环境（洞穴、裂缝）中，与光合共生体具有兼性关系。我们认为，这种现有的表型有助于定居在中层带。这一观察结果强调了其他海洋物种垂直迁移的潜力。
