Minimizing wildlife impacts for offshore wind energy development: Winning tradeoffs for seabirds in space and cetaceans in time

Although offshore wind energy development (OWED) offers a much-needed renewable energy alternative to fossil fuels, holistic and effective methods for evaluating environmental impacts on wildlife in both space and time have been lacking. The lengthy environmental compliance process, estimated to incur a 7–10 year permitting timeline [1], has been identified as a significant impediment to offshore energy development in U.S. waters. During operation, seabirds can collide and be displaced by turbines. During episodic pre-operation phases, cetaceans are most heavily impacted acoustically by pile driving (and similarly seismic air gun surveys for oil and gas exploration). The varying nature of impacts in space and time leads us to conclude that sites should be selected in space to minimize long-term operational impacts on seabirds, and timing of surveying and construction activities to be conducted in times of the year when sensitive migratory marine mammals are least present. We developed a novel spatiotemporal decision support framework that interactively visualizes tradeoffs between OWED industry profits and wildlife sensitivities, in both space and time. The framework highlights sites on a map that are the most profitable and least sensitive to seabirds. Within the U.S. Mid-Atlantic study area, the New York Call Areas are particularly well optimized for minimal impact on seabirds with maximal profits to OWED. For a given site, pre-operational activities (e.g. pile driving and seismic air gun surveying) are advised by cetacean sensitivity across months of the year that minimize impacts on migratory cetaceans, particularly those of highest conservation concern such as the North Atlantic right whale (Eubalaena Glacialis). For instance, within optimal sites for the New York Call Area the least impacting months are May and June. Other taxa are certainly affected by OWED and should be incorporated into this framework, but data on their distributions and/or sensitivities is currently less well known. Built with open-source software made publicly available, the authors hope this framework will be extended even more comprehensively into the future as our knowledge on species distributions and OWED sensitivities expands for streamlining environmental compliance.

尽管海上风电开发（offshore wind energy development, OWED）作为化石燃料的替代性可再生能源方案，能够有效缓解能源需求，但目前仍缺乏可在时空维度上全面且高效评估其对野生动物环境影响的系统性方法。据估算，美国海域内的海上风电开发需经历长达7至10年的环境合规审批流程[1]，这一冗长的流程已被证实是阻碍海上能源开发的关键因素。在项目运营阶段，海鸟可能与风力涡轮机发生碰撞，或因涡轮机的干扰而被迫迁徙流离。在阶段性的项目预运营阶段，鲸类会受到打桩作业（以及油气勘探中类似的气枪震源勘探）带来的严重声学干扰。鉴于环境影响在时空维度上的异质性，我们认为应从空间维度优化场址选择，以最大程度降低运营阶段对海鸟的长期影响；同时，勘测与施工作业的时间安排应避开敏感洄游海洋哺乳动物的主要活动期。为此，我们研发了一款全新的时空决策支持框架，可在时空维度上交互式可视化展示海上风电开发产业收益与野生动物敏感性之间的权衡关系。该框架可在地图上标注出兼具高开发收益与低海鸟敏感性的最优场址。在美国中大西洋研究区域内，纽约招标区（New York Call Areas）的优化方案尤为出色，可在最大化海上风电开发收益的同时，将对海鸟的影响降至最低。针对特定场址，预运营作业（如打桩与气枪震源勘探）的开展时间应参考全年各月份的鲸类敏感性分布，以最大程度降低对洄游鲸类的影响，尤其是那些具有极高保护价值的物种，例如北大西洋露脊鲸（Eubalaena Glacialis）。例如，在纽约招标区的最优场址中，对鲸类影响最小的时段为每年5月与6月。当然，其他类群的生物也会受到海上风电开发的影响，理应被纳入该框架，但目前关于这些生物的分布与敏感性的数据仍较为匮乏。本框架基于开源软件开发并已公开，作者期望随着我们对物种分布与海上风电开发敏感性的认知不断深化，该框架能够得到更全面的扩展，从而助力简化环境合规流程。