U.S. Fish and Wildlife Service, 1011 E Tudor Rd., Anchorage, AK 99503, USA.
RPS-ASA, 55 Village Square Dr., South Kingstown, RI 02879, USA.
Environ Pollut. 2018 Apr;235:652-659. doi: 10.1016/j.envpol.2017.12.057. Epub 2018 Jan 12.
Sea ice decline is anticipated to increase human access to the Arctic Ocean allowing for offshore oil and gas development in once inaccessible areas. Given the potential negative consequences of an oil spill on marine wildlife populations in the Arctic, it is important to understand the magnitude of impact a large spill could have on wildlife to inform response planning efforts. In this study we simulated oil spills that released 25,000 barrels of oil for 30 days in autumn originating from two sites in the Chukchi Sea (one in Russia and one in the U.S.) and tracked the distribution of oil for 76 days. We then determined the potential impact such a spill might have on polar bears (Ursus maritimus) and their habitat by overlapping spills with maps of polar bear habitat and movement trajectories. Only a small proportion (1-10%) of high-value polar bear sea ice habitat was directly affected by oil sufficient to impact bears. However, 27-38% of polar bears in the region were potentially exposed to oil. Oil consistently had the highest probability of reaching Wrangel and Herald islands, important areas of denning and summer terrestrial habitat. Oil did not reach polar bears until approximately 3 weeks after the spills. Our study found the potential for significant impacts to polar bears under a worst case discharge scenario, but suggests that there is a window of time where effective containment efforts could minimize exposure to bears. Our study provides a framework for wildlife managers and planners to assess the level of response that would be required to treat exposed wildlife and where spill response equipment might be best stationed. While the size of spill we simulated has a low probability of occurring, it provides an upper limit for planners to consider when crafting response plans.
预计海冰的减少将增加人类进入北冰洋的机会，从而使曾经无法进入的地区能够进行近海石油和天然气开发。鉴于石油泄漏对北极海洋野生动物种群可能造成的潜在负面影响，了解大型泄漏可能对野生动物造成的影响的程度对于指导应急规划工作非常重要。在这项研究中，我们模拟了在秋季从楚科奇海的两个地点（一个在俄罗斯，一个在美国）释放 25000 桶石油并持续 30 天的石油泄漏事件，并跟踪了 76 天的石油分布情况。然后，我们通过将泄漏事件与北极熊栖息地和移动轨迹图重叠，来确定这种泄漏事件对北极熊及其栖息地可能产生的潜在影响。只有一小部分（1-10%）高价值的北极熊海冰栖息地受到了足以影响北极熊的石油直接影响。然而，该地区 27-38%的北极熊可能接触到了石油。石油始终有最高的可能性到达弗兰格尔岛和赫尔姆霍茨岛，这是重要的巢穴和夏季陆地栖息地。石油直到泄漏发生约 3 周后才到达北极熊。我们的研究发现，在最坏情况下的排放情景下，对北极熊可能产生重大影响，但表明仍有一段时间可以采取有效的遏制措施，使北极熊接触到石油的可能性最小化。我们的研究为野生动物管理者和规划者提供了一个框架，以评估处理暴露的野生动物所需的应对水平，以及溢油应急设备可能最好安置的地点。虽然我们模拟的泄漏规模发生的概率很低，但它为规划者提供了一个上限，以便在制定应对计划时考虑。
