The effects of flow velocity on the fitness-related behaviours of Mesocentrotus nudus remain largely unknown, greatly hampering the efficiency of stock enhancement. To explore the appropriate velocities for stock enhancement, we investigated dislodgement and immobilization velocities up to 90 cm s−1. The experimental results showed that M. nudus (test diameter of ~30 mm) were dislodged at 73.50 ± 7.7 cm s−1 and that M. nudus movement occurred only when the flow velocity was less than 33.40 ± 2.7 cm s−1. Three flow velocities less than 33.40 ± 2.7 cm s−1 (2, 10 and 20 cm s−1) were subsequently used to study the effects of flow velocities on covering behaviour and the righting response time of M. nudus. The downstream movement velocity of M. nudus was significantly larger than that upstream at 2 cm s−1 (P = 0.016) and 10 cm s−1 (P = 0.008), but not at 20 cm s−1 (P = 0.222). The righting response time of M. nudus was significantly longer at 20 cm s−1 than that at 2 cm s−1 (P = 0.015). The present study indicates that a flow velocity less than 20 cm s−1, preferably 2–10 cm s−1, is probably appropriate for the stock enhancement of M. nudus. Notably, the current study is a laboratory investigation without considering the hydrographic complexity in the field. Further studies should be carried out to investigate the long-term effects of water flow on feeding and growth of M. nudus both in the laboratory and the field.

中文翻译：

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流速对海胆 Mesocentrotus nudus 健康相关行为的影响：关于种群增强的新信息

流速对体适能相关行为的影响裸中尾鱼仍然很大程度上未知，极大地阻碍了库存增加的效率。为了探索库存增强的适当速度，我们研究了高达 90 cm s 的移位和固定速度-1. 实验结果表明，M. nudus（测试直径约为 30 mm）在 73.50 ± 7.7 cm s 处脱落-1然后M. nudus仅当流速小于 33.40 ± 2.7 cm s 时才会发生运动-1. 三个流速小于 33.40 ± 2.7 cm s-1（2、10 和 20 cm s-1) 随后用于研究流速对覆盖行为和翻正响应时间的影响M. nudus. 下游运动速度M. nudus在 2 cm s 处明显大于上游-1(磷= 0.016) 和 10 cm s-1(磷= 0.008)，但不是在 20 cm s-1(磷= 0.222)。扶正响应时间M. nudus在 20 cm s 处明显更长-1比 2 cm s-1(磷= 0.015)。本研究表明，流速小于 20 cm s-1, 最好是 2-10 cm s-1, 可能适用于库存增强M. nudus. 值得注意的是，目前的研究是一项实验室调查，没有考虑该领域的水文复杂性。应进行进一步的研究，以调查水流对摄食和生长的长期影响。M. nudus在实验室和现场。