Abstract Cold-water corals form high biodiversity habitats in the deep sea. They are generally long-lived, slow-growing, and thus particularly vulnerable to anthropogenic impact. We used high-definition imagery to quantify the impact and assess the recovery of deep-sea corals that were affected by the 2010 Deepwater Horizon oil spill in the Gulf of Mexico. Over three hundred Paramuricea spp. colonies were imaged yearly between 2011 and 2017 at five sites, and the images were digitized to quantify health, hydroid overgrowth, identify branch loss, and track recovery patterns. Although the median level of impact decreased after 2011 at all impacted sites, it has been stable since then and remained higher than at the reference sites. Recovery depended on the initial level of impact to the colonies, which negatively affected the ability of individual branches to recover or remain healthy. The effect of initial impact on recovery between consecutive years was still visible seven years after the spill, indicating a long-term, non-acute, impact on the colonies. Injured corals were also more likely to lose branches, and branch loss was still significantly higher at some of the impacted sites between 2016 and 2017, indicating an ongoing effect of the spill, which may eventually lead to delayed mortality. The methodology we employed allows us to successfully detect small changes in the health of corals. We suggest the establishment of image-based coral-monitoring sites to collect baseline data on coral biology, assess the efficacy of Marine Protected Areas, and detect future anthropogenic impact to these vulnerable deep-sea ecosystems.

中文翻译：

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经过七年的监测，深水地平线漏油对深海珊瑚的长期影响

摘要 冷水珊瑚在深海形成了高度生物多样性的栖息地。它们通常寿命长、生长缓慢，因此特别容易受到人为影响。我们使用高清图像来量化影响并评估受 2010 年墨西哥湾深水地平线漏油事件影响的深海珊瑚的恢复情况。超过三百种Paramuricea spp。2011 年至 2017 年间，每年在五个地点对菌落进行成像，并将图像数字化以量化健康、水生植物过度生长、识别分支损失并跟踪恢复模式。尽管 2011 年后所有受影响地点的影响中位数水平有所下降，但此后一直保持稳定，并保持高于参考地点的水平。恢复取决于对殖民地的初始影响程度，这对单个分支恢复或保持健康的能力产生了负面影响。在泄漏事件发生七年后，对连续几年恢复的初始影响仍然可见，表明对殖民地的长期、非急性影响。受伤的珊瑚也更有可能失去树枝，2016 年至 2017 年期间，一些受影响地点的树枝损失仍然明显更高，表明泄漏的持续影响，最终可能导致死亡延迟。我们采用的方法使我们能够成功检测珊瑚健康的微小变化。我们建议建立基于图像的珊瑚监测站点，以收集珊瑚生物学的基线数据，评估海洋保护区的功效，并检测未来对这些脆弱的深海生态系统的人为影响。