During the dependency period in mammals with parental care, offspring must develop the behavioral skills that allow them to forage independently and thus survive into early adulthood. Deep-diving Weddell seals (Leptonychotes weddellii) are a model species for research on diving physiology, yet previous studies lack a thorough investigation into the diving behavior of dependent pups when they first begin to enter the water. To capture fine-scale dive behavior during the dependency period, we deployed time-depth recorders (TDRs) on Weddell seal pups (n = 18) from the age of 1 week through 7 weeks, during the 2017 and 2019 breeding seasons in McMurdo Sound, Antarctica. Dive parameters were correlated with time of day, age, sex, and weaning status, to characterize diving behavior, and we used raw wet/dry data to determine which times of the day pups were most likely to be in the water. Pups made their deepest and longest dives and had the longest post-dive durations in the morning hours. Pups were in the water more during the late night and morning hours than in the afternoon. Whereas dive depth significantly increased with age, dive duration significantly increased with age and after weaning. Post-dive duration significantly decreased with age and after weaning. We discuss how dependent pups may prioritize the development of swimming and navigational abilities as opposed to building and practicing foraging skills.

中文翻译：

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威德尔海豹（Leptonychotes weddellii）幼崽的早期潜水行为

在有父母照顾的哺乳动物的依赖期，后代必须发展行为技能，使它们能够独立觅食，从而存活到成年早期。深潜威德尔海豹 (Leptonychotes weddellii) 是潜水生理学研究的典范物种，但之前的研究缺乏对幼崽刚开始入水时的潜水行为进行彻底调查。为了捕捉依赖期间的精细潜水行为，我们在麦克默多湾的 2017 年和 2019 年繁殖季节为 1 周至 7 周龄的威德尔海豹幼崽 (n = 18) 部署了时间深度记录器 (TDR) , 南极洲。潜水参数与一天中的时间、年龄、性别和断奶状态相关联，以表征潜水行为，我们使用原始的湿/干数据来确定一天中幼犬最有可能在水中的时间。小狗进行了最深和最长的潜水，并且在早上的潜水后持续时间最长。与下午相比，幼犬在深夜和早上更多地在水中。虽然潜水深度随着年龄的增长而显着增加，但潜水持续时间随着年龄和断奶后显着增加。潜水后持续时间随着年龄和断奶后显着减少。我们讨论了依赖幼崽如何优先发展游泳和导航能力，而不是建立和练习觅食技能。与下午相比，幼犬在深夜和早上更多地在水中。虽然潜水深度随着年龄的增长而显着增加，但潜水持续时间随着年龄和断奶后显着增加。潜水后持续时间随着年龄和断奶后显着减少。我们讨论了依赖幼崽如何优先发展游泳和导航能力，而不是建立和练习觅食技能。与下午相比，幼犬在深夜和早上更多地在水中。虽然潜水深度随着年龄的增长而显着增加，但潜水持续时间随着年龄和断奶后显着增加。潜水后持续时间随着年龄和断奶后显着减少。我们讨论了依赖幼崽如何优先发展游泳和导航能力，而不是建立和练习觅食技能。