Collaborative Research: Recovery of Seamount Precious Coral Beds From Heavy Trawling Disturbance

复原力和相关的恢复概念提供了对生态系统功能、连通性和演替的洞察。在海洋领域，大多数复原力研究侧重于浅水生态系统，但深海越来越多的人为影响使深海复原力和恢复的研究变得至关重要，深海硬底质生境和大规模扰动受到的关注最少。具有讽刺意味的是，对海底的关键人为影响之一--拖网捕鱼--为理解从大规模干扰中恢复的过程提供了一种实验设计。海山有很高比例的硬底质生境，采样地点谨慎，而且受到拖网捕鱼的广泛干扰，为研究复原力的恢复方面提供了一个极好的天然实验室。此外，海山上深海珊瑚的丰富性、数量优势、高生物量和多样性使它们成为这些研究的理想模式生物。该项目的目标是检查遥远的西北夏威夷群岛和皇帝海山链的一系列地点，以解决这一假设，该假说基于对受干扰海山的低弹性和十年恢复时间的预测，即尽管拖网捕鱼30多年前结束，但西北夏威夷群岛的深海珊瑚床仍未恢复。为了验证这一假设，PIS将使用自动和远程水下航行器在三个水平的拖网捕鱼强度下对一系列重复的海山进行调查，并对海山动物，特别是深海珊瑚进行有针对性的采样。PIS将侧重于海山群落的三个具体方面：群落结构，使用经核实的大小-年龄曲线的珍贵珊瑚的年龄结构，以及使用DNA微卫星的珍贵珊瑚的遗传结构。使用这些方法，PIs将能够预测自珊瑚在任何特定海山上殖民以来的时间以及最近殖民者的来源人口。这些海山代表着自专属经济区建立以来增加的时间因素的自然实验，并提供了一个在十年时间尺度上解决海山恢复问题的无与伦比的机会。老化工具和微卫星的强大组合将使PI不仅可以限制深海珊瑚殖民的时间尺度，而且还可以限制殖民者的招募速度和来源。这些结果将对海山上的关键生态过程提供重要的见解，从而为进一步的科学和管理提供信息。这项提议将支持两名处于职业生涯早期的STEM科学家。它还将通过培训两名研究生和本科生作为研究实习，帮助培养一支有竞争力的STEM劳动力队伍。除了初级科学，私人侦察还将获得样本和基因数据，其他研究人员将分别通过博物馆和公共数据库获取这些样本和基因数据。

Resilience, and the related concept of recovery, provides insights into ecosystem function, connectivity, and succession. In the marine realm, most resilience studies have focused on shallow-water ecosystems but increasing anthropogenic impacts in the deep-sea are making studies of resilience and recovery in the deep-sea time-critical, with deep-sea hard-substrate habitats and large-scale disturbances having received the least attention. Ironically one of the key anthropogenic impacts to the seafloor, fish trawling, provides an experimental design to understand processes of recovery from large-scale disturbance. Seamounts, with a high proportion of hard-substrate habitat, discreet locations for sampling, and extensive disturbance from fish trawling, provide an excellent natural laboratory to study the recovery aspect of resilience. Additionally, the abundance, numerical dominance, high biomass, and diversity of deep-sea corals on seamounts make them ideal model organisms for these studies.The goal of this project is to examine a series of locations in the far Northwestern Hawaiian Islands (NWHI) and the Emperor Seamount Chain (ESC) to address the hypothesis, based on predictions of low resilience and decadal recovery times for disturbed seamounts, that deep-sea coral beds in the NWHI have not recovered despite the end of trawling 30+ years ago. To test this hypothesis, the PIs will survey a series of replicate seamounts at three levels of fish trawling intensity using autonomous and remote underwater vehicles to conduct surveys and targeted sampling of the seamount fauna and especially deep-sea corals. The PIs will focus on three specific aspects of the seamount communities: community structure, age structure of precious corals using a verified size-age curve, and genetic structure of precious corals using DNA microsatellites. Using these methods the PIs will be able to predict the time since coral colonization on any particular seamount as well as source populations of the recent colonizers.These seamounts represent a natural experiment with the added factor of time since the establishment of the exclusive economic zone, and provide an unparalleled opportunity to address seamount recovery on decadal time scales. The powerful combination of aging tools and microsatellites will allow the PIs not only to constrain time scales of deep sea coral colonization, but also rates of recruitment and source of the colonizers. The results will provide significant insights into key ecological processes on seamounts, thus serving to inform further science as well as management. This proposal will support two STEM scientists in the early stages of their careers. It will also contribute to developing a competitive STEM workforce through training of two graduate students as well as undergraduate students as research internships. Besides the primary science, the PIs will also obtain samples and genetic data that will be made accessible to other researchers through museums and public databases, respectively.