Coppersmith Shannon, Goiran Claire, Sanders Kate Laura, Crowe-Riddell Jenna Margaret, Chateau Olivier, Shine Richard, Udyawer Vinay
School of Biological Sciences, The University of Adelaide, Adelaide, South Australia, Australia.
ISEA & LabEx Corail, Université de La Nouvelle-Calédonie, Nouméa, New Caledonia, New Caledonia.
Mov Ecol. 2025 Aug 28;13(1):62. doi: 10.1186/s40462-025-00592-z.
The efficient acquisition of two critical but spatially separated resources -food and oxygen- governs the daily movements and diving patterns of air-breathing aquatic animals. Unlike pinnipeds, turtles and seabirds, fully marine ('true') sea snakes spend their entire lifecycle at sea and have evolved specialised movement behaviours. However, fine-scale data on the diving behaviour of free-ranging sea snakes remain scarce, limiting our understanding of their ecology and vulnerability to anthropogenic threats.
We used acoustic telemetry to track five individuals of two benthic-foraging sea snake species (Hydrophis stokesii, H. major) in Exmouth Gulf, Western Australia, and Baie des Citrons, New Caledonia. Each snake was continuously tracked using a directional hydrophone for up to 18 h, generating high-resolution, three-dimensional dive paths. After filtering, we analysed 106 dives from 46 h of tracking.
Sea snakes primarily conducted U- and S-shaped dives and spent on average 97.2% of their time submerged. Most U-shaped dives were characterised by limited vertical and horizontal movement. S-shaped dives were more complex, with variable time on the seafloor and occasionally interrupted gradual ascents. Dive duration was positively correlated with post-dive surface interval, while depth and duration of the gradual ascent phase were influenced by environmental depth. We also identified distinctive, repetitive undulations ('wiggles') in the depth profiles of several dives completed by all three tracked H. stokesii.
These high-resolution data provide the first insights into the fine-scale diving patterns of benthic-foraging sea snakes. Like surface-foraging species, they appear to regulate air intake based on environmental depth and may be neutrally buoyant in the gradual ascent phase of S-shaped dives. We hypothesise that this phase facilitates efficient horizontal travel, despite potential increases in predation risk. The 'wiggles' observed in H. stokesii may have a functional role in buoyancy control, energy conservation, or foraging. Our study contributes to a deeper understanding of sea snake diving strategies, with implications for their ecology, physiology, and conservation.
高效获取两种关键但空间上分离的资源——食物和氧气，决定了水生呼吸空气动物的日常活动和潜水模式。与鳍足类动物、海龟和海鸟不同，完全生活在海洋中的（“真正的”）海蛇在海上度过其整个生命周期，并进化出了特殊的运动行为。然而，关于自由活动海蛇潜水行为的精细尺度数据仍然稀缺，这限制了我们对它们的生态学以及它们在面对人为威胁时的脆弱性的理解。
我们使用声学遥测技术在西澳大利亚的埃克斯茅斯湾和新喀里多尼亚的柠檬湾追踪了两种底栖觅食海蛇物种（斯托克斯海蛇、巨头海蛇）的五只个体。每只蛇都使用定向水听器连续追踪长达18小时，生成高分辨率的三维潜水路径。经过筛选，我们分析了46小时追踪过程中的106次潜水。
海蛇主要进行U形和S形潜水，平均有97.2%的时间处于水下。大多数U形潜水的特点是垂直和水平移动有限。S形潜水更复杂，在海底停留的时间可变，偶尔会有逐渐上升的过程被打断。潜水持续时间与潜水后水面间隔呈正相关，而逐渐上升阶段的深度和持续时间受环境深度影响。我们还在所有三只被追踪的斯托克斯海蛇完成的几次潜水深度剖面图中发现了独特的、重复的波动（“摆动”）。
这些高分辨率数据首次揭示了底栖觅食海蛇的精细潜水模式。与表层觅食物种一样，它们似乎根据环境深度调节空气摄入量，并且在S形潜水的逐渐上升阶段可能是中性浮力的。我们假设这个阶段有助于高效的水平移动，尽管捕食风险可能会增加。在斯托克斯海蛇中观察到的“摆动”可能在浮力控制、能量守恒或觅食方面具有功能性作用。我们的研究有助于更深入地理解海蛇的潜水策略，对它们的生态学、生理学和保护具有重要意义。
