Recent estimates of blue (Balaenoptera musculus) and humpback (Megaptera novaeangliae) whale ship-strike deaths on the US west coast are above the Potential Biological Removal limit determined by the National Marine Fisheries Service. Beginning in 2015, the National Oceanographic and Atmospheric Administration requested voluntary Vessel Speed Reductions (VSR) in the designated shipping routes off San Francisco, California, USA, in order to decrease whale mortality from ship strikes. We applied a ship strike model based on whale density and Automatic Identification System (AIS) vessel data. We bootstrapped speeds from vessels that transited when no VSR was in place to assess the effect of the VSR on strike mortality rates. Finally, we calculated the expected mortality for hypothetical compliance scenarios by programmatically imposing speed caps. Average predicted mortality for the region was 2.7 blue whales and 7.0 humpback whales in a 4 month period. Compared to years prior to the VSR (2012−2014), vessel speeds during the VSR were slower. This lowered blue whale deaths within the shipping lanes by 11–13% and humpback whale deaths by 9–10% in 2016−2017. If 95% of mariners adhered to recommended 10 knot (kn) limits in the shipping lanes alone, we predicted twice as many blue whale and 3 times as many humpback whale deaths would be avoided relative to current adherence. Adding a 10 kn speed limit (with 95% coope ration) at the ends of each of the lanes would result in about 5and 4-fold reductions in blue whale and humpback whale mortality, respectively, relative to current practices. Our approach can evaluate ship strikes and mitigation measures for whale populations around the globe.

中文翻译：

---

评估减速措施对降低高风险地区鲸鱼撞击死亡率的有效性

最近对美国西海岸蓝鲸（Balaenoptera musculus）和座头鲸（Megaptera novaeangliae）鲸鱼船撞死亡的估计高于国家海洋渔业局确定的潜在生物清除限制。从 2015 年开始，美国国家海洋和大气管理局要求在美国加利福尼亚州旧金山附近的指定航线上自愿降低船舶速度 (VSR)，以减少船舶撞击造成的鲸鱼死亡率。我们应用了基于鲸鱼密度和自动识别系统 (AIS) 船舶数据的船舶撞击模型。我们从没有 VSR 时通过的船只引导速度，以评估 VSR 对罢工死亡率的影响。最后，我们通过以编程方式施加速度上限来计算假设合规场景的预期死亡率。该地区在 4 个月内的平均预测死亡率为 2.7 头蓝鲸和 7.0 头座头鲸。与 VSR 之前的几年（2012-2014 年）相比，VSR 期间的船舶速度较慢。这使 2016-2017 年航道内的蓝鲸死亡人数减少了 11-13%，座头鲸死亡人数减少了 9-10%。如果 95% 的海员仅在航道上遵守建议的 10 节 (kn) 限制，我们预测相对于目前的遵守情况，蓝鲸数量将增加两倍，座头鲸死亡人数将减少 3 倍。相对于目前的做法，在每条车道的末端增加 10 kn 的速度限制（95% 合作）将分别使蓝鲸和座头鲸的死亡率减少约 5 倍和 4 倍。我们的方法可以评估船舶撞击和全球鲸鱼种群的缓解措施。