Collaborative Research: Hunting Behavior and Energetics of Free-Ranging Weddell Seals

这个合作研究项目的重点是韦德尔海豹能够在寒冷、黑暗的南极快冰环境中觅食的行为和精力适应。 为了回答这个问题，假设相关的一般觅食策略，觅食位置，搜索模式，猎物检测，运动性能，潜水成本和觅食效率的自由放养威德尔海豹（Leptonychotes weddellii）将进行测试。 此外，还将研究潜水期间的运动性能和行为，以估计与狩猎有关的成本和从狩猎中获得的好处（捕获猎物的类型和频率）。 这项研究将为海洋哺乳动物觅食策略提供独特的见解，并将有助于生理学（潜水和能量学）和生态学（觅食理论和行为生态学）领域。 拟议的研究建立在对麦克默多湾威德尔海豹的研究基础上，使用动物携带的视频系统/数据记录器记录海洋哺乳动物在深度的行为、生理和运动性能。 这提供了威德尔海豹狩猎策略，捕食者-猎物的相互作用和相应的估计潜水代谢的第一次观察。 研究中使用的隔离冰孔协议允许海豹选择潜水的深度和持续时间，但它们必须返回到一个地方呼吸，这限制了它们的活动范围。 此外，它们无法离开水面或与其他海豹互动，并且可能比自然觅食时暴露在更低的猎物密度下。 新的焦点是完全自由放养的海豹的行为和能量学，所有重要的限制都已被删除。 虽然目前的研究已经证明了威德尔海豹觅食的重要新原则，并增加了对潜水行为和游泳表现的理解，但现在必须确定这些原则是否适用于不受约束的动物。 这项研究将继续雇用一个多学科的科学家团队，并提供高技能的技术支持。 研究结果将促进对威德尔海豹觅食生态学的理解，并为其他海洋哺乳动物物种的类似研究奠定基础，这些物种在开放的海洋中更难研究。 最后，通过将研究从孤立的冰洞扩展到完全自由放养的条件，这项研究将为威德尔海豹在南极海洋生态系统中作为顶级捕食者的作用提供新的见解。

The focus of this collaborative research project is on the behavioral and energetic adaptations enable Weddell seals to forage in the cold, dark, Antarctic fast-ice environment. To answer this question, hypotheses related to general foraging strategy, foraging location, searching mode, prey detection, locomotor performance, the cost of diving and foraging efficiency of free-ranging Weddell seals (Leptonychotes weddellii) will be tested. In addition, locomotor performance and behavior during diving to estimate the costs associated with hunting and the benefits gained from hunting (type and frequency of prey captures) will be examined. This study will provide unique insight into marine mammal foraging tactics and will contribute to fields of physiology (diving and energetics) and ecology (foraging theory and behavioral ecology). The proposed study builds on research on Weddell seals in McMurdo Sound using an animal-borne video system/data logger to record the behavior, physiology and locomotor performance of marine mammals at depth. This provided first observations of Weddell seal hunting strategies, predator-prey interactions and corresponding estimates of diving metabolism. The isolated-ice-hole protocol used in the study allows seals to choose the depth and duration of a dive, but they must return to a single place to breathe, which limits their range of movement. In addition, they are unable to haul out of the water or interact with other seals and may be exposed to lower prey densities than when foraging naturally. The new focus is the behavior and energetics of completely free-ranging seals, for which all significant constraints have been removed. Although the current study has demonstrated important new principles in Weddell seal foraging and has increased understanding of diving behavior and swimming performance, it is now essential to determine whether those principles apply to unconstrained animals. The study will continue to employ a multidisciplinary team of scientists with highly skilled technical support. The results will advance the understanding of the foraging ecology of Weddell seals and create a basis for similar research on other species of marine mammals that are more difficult to study in the open ocean. Finally, by extending the study from an isolated ice hole to completely free-ranging conditions, this research will provide new insight into the role of Weddell seals as apex predators in the Antarctic marine ecosystem.