Collaborative Research: Determining Factors Affecting Distribution and Population Variability of the Ice-obligate Weddell Seal

威德尔海豹是世界上最靠南的哺乳动物，在南极洲周围有极地分布；南极洲的麦克默多海峡是地球上研究得最好的哺乳动物种群之一。然而，尽管如此，人们对非洲大陆人口在气候变化下的生存状况知之甚少。一个复杂的问题是南极商业企业的潜在影响：一个以齿鱼为目标的渔业，齿鱼是威德尔海豹的重要猎物。虽然在繁殖季节很容易发现和统计威德尔海豹的数量，但由于在南极洲大片地区进行调查的后勤困难，目前还没有对整个大陆威德尔海豹数量的可靠估计。要了解海豹种群对渔业和气候变化的反应，需要进行大规模的估计，因为这些变化的驱动因素比任何单一种群都要大，并且可能对大陆不同地区的海豹产生不同的影响。当深色海豹在冰上活动时，我们将利用它们容易被探测到的优势，从卫星图像中估算出它们的丰度。该项目将生成南极威德尔海豹全球分布和数量的基线数据，并将环境变量与种群变化联系起来，以更好地了解随着海冰栖息地的不断变化，该物种将如何生存。这些结果将有助于理清气候变化和渔业作业的影响，这些结果对于制定有关渔业捕捞限制、对环境的影响和海洋保护区价值的适当国际政策是必要的。该项目还将进一步实现国家科学基金会培养新一代科学家和向公众提供科学发现的目标。它将通过与几个非政府组织和一般公众的联系，让所有年龄的“坐卧不坐”的科学家参与进来。任何可以上网的人，包括身体上无法直接参与实地研究的人，都可以参与这个项目，同时通过项目的互动网站了解极地生态的多个方面。具体而言，本研究项目将：1)量化威德尔海豹在南极洲周围的分布；2)确定环境变量（如快冰范围、海洋生产力、水深测量）对栖息地适宜性和占用的影响。为此，该项目将通过一个商业公民科学平台，在高分辨率卫星图像上对海豹进行众包计数。然后，通过广义线性模型将整个大陆海豹的变化与栖息地变量联系起来。将测试特定变量，如快速结冰范围，以确定它们对人口在空间和时间上的变化的影响。该项目包括一个严格的计划，以确保数据集的质量控制，包括来自其他国家科学基金会南极科学计划同时资助的本地化项目的地面真实数据。

The Weddell seal is the southern-most mammal in the world, having a circumpolar distribution around Antarctica; the McMurdo Sound population in Antarctica is one of the best-studied mammal populations on earth. However, despite this, an understanding of how populations around the continent will fare under climate change is poorly understood. A complicating matter is the potential effects of a commercial enterprise in the Antarctic: a fishery targeting toothfish, which are important prey for Weddell seals. Although the species is easily detected and counted during the breeding season, no reliable estimates of continent-wide Weddell seal numbers exist, due to the logistic difficulties of surveying vast regions of Antarctica. Large-scale estimates are needed to understand how seal populations are responding to the fishery and climate change, because these drivers of change operate at scales larger than any single population, and may affect seals differently in different regions of the continent. We will take advantage of the ease of detectability of darkly colored seals when they the on ice to develop estimates of abundance from satellite images. This project will generate baseline data on the global distribution and abundance of Weddell seals around the Antarctic and will link environmental variables to population changes to better understand how the species will fare as their sea ice habitat continues to change. These results will help disentangle the effects of climate change and fishery operations, results that are necessary for appropriate international policy regarding fishery catch limits, impacts on the environment, and the value of marine protected areas. The project will also further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. It will engage "arm-chair" scientists of all ages through connections with several non-governmental organizations and the general public. Anyone with access to the internet, including people who are physically unable to participate in field research directly, can participate in this project while simultaneously learning about multiple aspects of polar ecology through the project's interactive website. Specifically, this research project will: 1) Quantify the distribution of Weddell seals around Antarctica and 2) Determine the impact of environmental variables (such as fast ice extent, ocean productivity, bathymetry) on habitat suitability and occupancy. To do this, the project will crowd-source counting of seals on high-resolution satellite images via a commercial citizen science platform. Variation in seal around the continent will then be related to habitat variables through generalized linear models. Specific variables, such as fast ice extent will be tested to determine their influence on population variability through both space and time. The project includes a rigorous plan for ensuring quality control in the dataset including ground truth data from other, localized projects concurrently funded by the National Science Foundation's Antarctic Science Program.