Marine Mammal Watch, collected from the Research Vessel Sikuliaq, Northern Bering Sea to Chukchi Sea, 2023

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覆盖范围的大幅缩减与海表温度的持续上升。该区域核心科学不确定性之一，是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，以及秋季海冰形成时间的滞后现象。上层海洋水文特征、浮游生物生产力与平流输送、水层-底栖耦合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，一支国际科学家合作团队搭建了协同式分布式生物观测站（Distributed Biological Observatory, DBO），该观测站包含多营养级的选定生物测量项目，同时配套卫星与锚系观测数据。当前DBO聚焦5个区域生物"热点"站位，可在横跨纬度梯度的生物高生产力区域开展标准化采样与监测：DBO 1（SLIP）——圣劳伦斯岛（St. Lawrence Island, SLI）以南海域，DBO 2（奇里科夫）——圣劳伦斯岛以北海域，DBO 3（楚科奇海南部），DBO 4-NE（东北楚科奇海），以及DBO 5（巴罗峡谷）。除成套生物物理采样项目外，DBO还在可行条件下沿科考船航线开展海鸟调查与海洋哺乳动物观测，以实现对这些高营养级捕食者响应北极太平洋扇区海洋生态系统变化的监测。