Szereday Sebastian, Chew Kok Lynn, Voolstra Christian R
Non-profit enterprise for coral reef research and restoration, Coralku Solutions, Kuala Lumpur, Malaysia.
Department of Biology, University of Konstanz, Konstanz, Germany.
Commun Biol. 2025 Aug 28;8(1):1294. doi: 10.1038/s42003-025-08657-w.
Thermal screening of coral source material is likely crucial to enhancing long-term restoration success under ocean warming. It is unclear, however, whether reef-based donor colonies retain their thermal tolerance in a nursery environment. Here, we used CBASS acute thermal assays to compare standardized thermal tolerance thresholds (ED50s) of donor colonies from Acropora cytherea and Acropora florida from two sites in Pulau Lang Tengah, Malaysia to their 'nursery propagules' reared in a common garden coral nursery over 365 days. CBASS assays of reef-based donors and their nursery counterparts were conducted in parallel and over two seasons to assess retention of thermal tolerance following nursery rearing. After 6 months, average ED50s of A. cytherea nursery corals were significantly lower compared to their reef-based donor colonies, but such difference disappeared after 365 days. By comparison, no such differences were measurable for A. florida and thermal tolerances were retained. Further, we did not observe trade-offs between growth and thermal thresholds for either species. Based on our findings, in situ thermal tolerance differences are likely adaptive and, consequently, either retained or recovered in longer-term restoration settings. Our findings further imply that thermal screening should be conducted prior to nursery propagation to avoid selection based on long-term acclimation artifacts.
对珊瑚源材料进行热筛选可能对提高海洋变暖情况下长期恢复的成功率至关重要。然而，尚不清楚基于珊瑚礁的供体群体在育苗环境中是否能保持其耐热性。在此，我们使用CBASS急性热试验，比较了来自马来西亚浪中岛两个地点的多孔鹿角珊瑚和弗罗里达鹿角珊瑚的供体群体与其在普通花园珊瑚苗圃中饲养365天的“育苗繁殖体”的标准化耐热阈值（半数效应剂量）。对基于珊瑚礁的供体及其在苗圃中的对应物进行的CBASS试验是并行进行的，且跨越两个季节，以评估育苗饲养后耐热性的保持情况。6个月后，多孔鹿角珊瑚育苗珊瑚的平均半数效应剂量与其基于珊瑚礁的供体群体相比显著降低，但365天后这种差异消失。相比之下，弗罗里达鹿角珊瑚没有可测量的此类差异，且耐热性得以保持。此外，我们没有观察到这两个物种在生长和热阈值之间存在权衡。基于我们的研究结果，原位耐热性差异可能具有适应性，因此，在长期恢复环境中可能会保留或恢复。我们的研究结果还意味着，应在苗圃繁殖之前进行热筛选，以避免基于长期驯化假象的选择。
