Application of a multi-disciplinary approach to reveal population structure and Southern Ocean feeding grounds of humpback whales: Data and README

State-space modelled data and README files associated with Riekkola et al. (2018). Application of a multi-disciplinary approach to
reveal population structure and Southern Ocean feeding grounds of humpback
whales. Ecological Indicators, 89, 455-465.AbstractObtaining direct measurements to characterise ecosystem function can be hindered by remote or inaccessible regions. Next-generation satellite tags that inform increasingly sophisticated movement models, and the miniaturisation of animal-borne loggers, have enabled the use of animals as tools to collect habitat data in remote environments, such as the Southern Ocean. Research on the distribution, habitat use and recovery of Oceania’s humpback whales (Megaptera novaeangliae) has been constrained by the inaccessibility to their Antarctic feeding grounds and the limitations of technology. In this multi-disciplinary study, we combine innovative analytical tools to comprehensively assess the distribution and population structure of this marine predator throughout their entire migratory range. We used genotypeand photo-identification matches and conducted a genetic mixed-stock analysis to identify the breeding ground origins of humpback whales migrating past the Kermadec Islands, New Zealand. Satellite tracking data and a state-space model were then used to identify the migratory paths and behaviour of 18 whales, and to reveal their Antarctic feeding ground destinations. Additionally, we conducted progesterone assays and epigenetic aging to determine the pregnancy rate and age-profile of the population. Humpback whales passing the Kermadec Islands did not assign to a single breeding ground origin, but instead came from a range of breeding grounds spanning ∼3500 km of ocean. Sampled whales ranged from calves to adults of up to 67 years of age, and a pregnancy rate of 57% was estimated from 30 adult females. The whales migrated to the Southern Ocean (straight-line distances of up to 7000 km) and spanned ∼4500 km across their Antarctic feeding grounds. All fully tracked females with a dependent calf (n = 4) migrated to the Ross Sea region, while 70% of adults without calves (n = 7) travelled further east to the Amundsen and Bellingshausen Seas region. By combining multiple research and analytical tools we obtained a comprehensive understanding of this wide-ranging, remote population of whales. Our results indicate a population recovering from exploitation, and their feeding ground distribution serves as an indicator of the resources available in these environments. The unexpected Kermadec Islands migratory bottle-neck of whales from several breeding grounds, variable distribution patterns by life history stage and high pregnancy rates will be important in informing conservation and management planning, and for understanding how this, as well as other whale populations, might respond to emerging threats such as climate change.

本数据集收录了Riekkola等人（2018年）的研究相关状态空间模型数据和README文件。该研究运用跨学科方法，揭示了座头鲸（Megaptera novaeangliae）在南方海洋的种群结构和摄食地。由于南极摄食地的难以接近以及技术的局限性，对大洋洲座头鲸分布、栖息地利用和恢复的研究受到限制。在本项多学科研究中，我们结合创新的解析工具，全面评估了这一海洋捕食者在整个迁徙范围内的分布和种群结构。我们运用基因型和照片识别匹配，并进行了遗传混合种群分析，以确定经过新西兰克马德克群岛迁徙的座头鲸的繁殖地起源。随后，利用卫星跟踪数据和状态空间模型，识别了18头鲸的迁徙路径和行为，并揭示了其南极摄食地的目的地。此外，我们还进行了孕酮检测和表观遗传衰老分析，以确定群体的妊娠率和年龄分布。经过克马德克群岛的座头鲸并非来自单一的繁殖地起源，而是来自跨越约3500公里海洋的多个繁殖地。样本鲸鱼年龄跨度从幼鲸到67岁的成年鲸，通过对30头成年雌鲸的估计，妊娠率达到了57%。这些鲸鱼迁徙至南方海洋（直线距离可达7000公里），并在其南极摄食地跨越约4500公里。所有携有幼崽的完全追踪雌鲸（n=4）均迁徙至罗斯海地区，而70%的无幼崽成年鲸（n=7）则向东迁徙至阿蒙森海和贝尔林寒海地区。通过结合多种研究和分析工具，我们获得了对这一广布、偏远鲸群群体的全面理解。我们的研究结果指示了正在从过度利用中恢复的群体，其摄食地分布可作为这些环境中资源可用性的指示器。来自多个繁殖地的鲸鱼在克马德克群岛迁徙的意外瓶颈、生命史阶段变化的分布模式以及高妊娠率对于制定保护和管理规划、以及理解这一群体以及其他鲸鱼群体如何应对诸如气候变化等新兴威胁具有重要意义。