Marine Mammal Watch, collected from the Research Vessel Sikuliaq, Northern Bering Sea to Chukchi Sea, 2024

The Pacific sector of the Arctic Ocean is experiencing major reductions in seasonal sea ice extent and increases in sea surface temperatures. One of the key uncertainties in this region is how the marine ecosystem will respond to seasonal shifts in the timing of spring sea ice retreat and/or delays in fall sea ice formation. Variations in upper ocean water hydrography, planktonic production and advection, pelagic-benthic coupling and sediment carbon cycling are all influenced by sea ice and temperature change. To more systematically track the broad biological response to sea ice retreat and associated environmental change, an international consortium of scientists have developed a coordinated Distributed Biological Observatory (DBO) that includes selected biological measurements at multiple trophic levels, along with satellite and mooring measurements. The DBO currently focuses on five regional biological "hotspot" locations that allows for consistent sampling and monitoring at biologically productive locations across a latitudinal gradient: DBO 1 (SLIP)-south of St. Lawrence Island (SLI), DBO2 (Chirikov)-north of SLI, DBO3 (southern Chukchi Sea), DBO4-NE (northeast) Chukchi Sea, and DBO5-Barrow Canyon. In addition to a suite of biophysical sampling, the DBO also includes seabird surveys and a marine mammal watch along the ship’s track whenever possible, to provide a means to detect responses of these upper-trophic level predators to changes in the Pacific Arctic marine ecosystem.北冰洋太平洋扇区正经历季节性海冰范围的大幅缩减与海表温度的持续升高。该区域的核心不确定性之一，在于海洋生态系统将如何响应春季海冰消退时间的季节性偏移，以及/或秋季海冰形成的延迟。上层海洋水文状况、浮游生物生产力与平流过程、浮游-底栖耦合作用以及沉积物碳循环的变化，均受海冰与温度变化的影响。为更系统地追踪海洋生物对海冰消退及相关环境变化的整体响应，一个由多国科学家组成的国际联盟开发了协同式分布式生物观测站（Distributed Biological Observatory, DBO）。该观测站涵盖多营养级生物测量项目，同时配套卫星与锚系观测方案。目前，DBO聚焦于5个区域性生物“热点”点位，可在横跨纬度梯度的生物高产出区域开展标准化采样与监测：DBO 1（SLIP）——圣劳伦斯岛（St. Lawrence Island, SLI）以南区域；DBO 2（奇里科夫）——圣劳伦斯岛以北区域；DBO 3（楚科奇海南部）；DBO 4-NE（楚科奇海东北部）；以及DBO 5（巴罗峡谷）。除整套生物物理采样项目外，DBO还会在可行条件下沿科考航线开展海鸟调查与海洋哺乳动物观测，以此为途径监测这些顶级营养级捕食者对太平洋北极海洋生态系统变化的响应。