Behavioral responses to light of early life stages provide insights on the development of photosensitivity in nocturnal species such as Stichopus cf. horrens. In this study, the onset of nocturnal feeding behavior, growth, and survival during early juvenile development (0.56 ± 0.16 cm; 47 days post-settlement) of the species were investigated for 30 days, in the presence (S) or absence (W) of artificial shelters and under three light regimes: constant light (24 L), constant dark (24D), and a 12 -h light, 12 -h dark period (12 L:12D). Juveniles in all treatments fed initially during daytime hours but eventually exhibited a shift to nocturnal feeding by day 11. This behavioral shift to nocturnality was delayed among individuals under constant dark conditions. Continuous light exposure without shelter resulted in low juvenile survival and mass mortality in some replicates of the treatment. In contrast, growth and survival were highest for juveniles in constant dark. This study showed the endogenous control of feeding in this species. It also demonstrated that growth increases significantly when early juveniles are reared with shelters or in constant dark. Optimizing the light regime and type of shelter can improve food accessibility and juvenile growth without hindering the development of photosensitivity in early juveniles. Further studies are needed to enhance the nursery culture of this species.

中文翻译：

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疣状海参 Stichopus cf. 早期幼鱼夜间摄食和光敏性的发育。霍伦斯

生命早期阶段对光的行为反应提供了对夜间物种（如刺参）光敏性发展的见解。恐怖。在这项研究中，在存在 (S) 或不存在 (W ) 的人工庇护所和三种光照条件：恒定光照 (24 L)、恒定黑暗 (24D) 和 12 小时光照、12 小时黑暗期 (12 L:12D)。所有处理中的幼鱼最初在白天进食，但最终在第 11 天表现出转向夜间进食。这种向夜间进食的行为转变在持续黑暗条件下的个体中被延迟。在一些重复的治疗中，没有庇护所的连续光照导致低幼鱼存活率和大量死亡率。相比之下，幼鱼在持续黑暗中的生长和存活率最高。该研究显示了该物种对摄食的内源控制。它还表明，当早期的幼鱼在庇护所或持续黑暗中饲养时，生长显着增加。优化光照条件和庇护所类型可以改善食物的可及性和幼鱼的生长，而不会阻碍幼鱼光敏性的发展。需要进一步研究以加强该物种的苗圃养殖。它还表明，当早期的幼鱼在庇护所或持续黑暗中饲养时，生长显着增加。优化光照条件和庇护所类型可以改善食物的可及性和幼鱼的生长，而不会阻碍幼鱼光敏性的发展。需要进一步研究以加强该物种的苗圃养殖。它还表明，当早期的幼鱼在庇护所或持续黑暗中饲养时，生长显着增加。优化光照条件和庇护所类型可以改善食物的可及性和幼鱼的生长，而不会阻碍幼鱼光敏性的发展。需要进一步研究以加强该物种的苗圃养殖。