The Role of Oceanographic Features and Prey Distribution on Foraging Energetics and Reproductive Success of the Antarctic Fur Seal, Arctocephalus Gazella

9726567 COSTA南大洋的海洋沿海和远洋环境的特点是季节性高生产力。在过去几十年中，人们已经清楚地看到，这些环境虽然总体上是生产性的，但也经历了相当大的年际和年际变化。 因此，脊椎动物捕食者的可用猎物资源可以是高度可变的空间和时间。 自20世纪80年代后期以来，南极半岛的北方南设得兰群岛地区的猎物资源的这种空间和时间的变化已被经验性地测量。南极软毛海豹是一种哺乳期短的亚极地迁徙otariid，是南设得兰群岛地区日益占主导地位的海洋捕食者。它的生活史模式的特点是觅食旅行与短期访问交替提供一个单一的后代;这使科学家能够在相同的时间和空间尺度上测量母体投资作为测量猎物的分布和丰度。该项目将量化觅食成本和产妇投资与观察到的南设得兰群岛的北极软毛海豹种群的战略变化。将使用最先进的技术，同时测量能量消耗、食物摄入、潜水深度、潜水持续时间、一天中的时间、潜水频率、游泳速度和觅食位置，以完成不同觅食模式的能量成本和效益。这些测量将与国家海洋和大气管理局的南极海洋生物资源方案进行的小规模和大规模海洋学调查同时进行，该方案也有助于支持这一项目。 这项研究将使科学家能够将生物学特征（猎物组成，分布和丰度）和觅食环境的物理特征与自由放养的海洋脊椎动物捕食者的觅食成功，母性投资和繁殖成功联系起来。

9726567 COSTA Marine coastal and pelagic environments of the Southern Ocean are characterized by seasonal high productivity. Over the last several decades it has become clear that these environments, while generally productive, also undergo considerable inter- and intra-annual variability. Consequently, available prey resources for vertebrate predators can be highly variable spatially and temporally. This spatial and temporal variability of prey resources has been measured empirically for the northern South Shetland Islands region of the Antarctic Peninsula since the late 1980's. The Antarctic fur seal, a sub-polar migratory otariid with a short lactation period, is an increasingly dominant marine predator of the South Shetlands region. Its life history is pattern is characterized by foraging trips alternating with short visits to provision a single offspring; this allows scientists to measure maternal investment on the same temporal and spatial scale as measurements of distribution and abundance of prey. This project will quantify the foraging costs and maternal investment associated with changes in strategies observed in populations of South Shetland Ataractic fur seals. Energetic costs and benefits of different foraging patterns with simultaneous measurement of energy expenditure, food intake, dive depth, dive duration, time of day, and dive frequency, swim speed and foraging location will be accomplished using state of the art techniques. These measurements will coincide with small and large scale oceanographic surveys to be conducted by the National Oceanic and Atmospheric Administration's Antarctic Marine Living Resources program, which is also contributing to the support of this project. The research will allow scientists to link biological characteristics (prey composition, distribution and abundance) and physical characteristics of the foraging environment with foraging success, maternal investment and reproductive success for a free-ranging marine ve rtebrate predator.