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

9726567南大洋的科斯塔海洋、沿海和远洋环境具有季节性高生产力的特点。在过去几十年中，人们清楚地看到，这些环境虽然总体上是富有成效的，但也经历了相当大的年际和年内变化。因此，脊椎动物捕食者可用的猎物资源在空间和时间上都可以高度可变。自20世纪80年代末S以来，对南极半岛南设得兰群岛北部地区猎物资源的这种时空变异性进行了经验性测量。南极毛海豹是一种亚极地迁徙的哺乳期短的海豹，是南设得兰地区日益占主导地位的海洋捕食者。其生活史是以觅食旅行和短暂探访交替进行的模式为特征的，以提供单一后代；这使科学家能够在与测量猎物分布和丰度相同的时间和空间尺度上衡量母体投资。该项目将量化与在南设得兰大西洋毛海豹种群中观察到的策略变化相关的觅食成本和产妇投资。不同觅食模式的能量成本和收益，以及同时测量能量消耗、食物摄入量、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将使用最先进的技术来完成。这些测量将与国家海洋和大气管理局南极海洋生物资源计划将进行的小规模和大规模海洋调查相吻合，该计划也有助于支持该项目。这项研究将使科学家能够将觅食环境的生物学特征(猎物组成、分布和丰度)和物理特征与自由活动的海洋脊椎动物捕食者的觅食成功、母体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.