RAPID: Collaborative Research: Predicting the Spread of Multi-Species Coral Disease Using Species Immune Traits

珊瑚礁生态系统以旅游、渔业和海岸保护等形式为美属维尔京群岛(USVI)和美国其他地区的社会提供了大量的经济资源。然而，珊瑚礁是最受威胁的海洋环境之一，珊瑚礁疾病正在对这些宝贵的系统产生毁灭性的影响。2019年初，发现了一种与石珊瑚组织丧失疾病(SCTLD)描述相匹配的多物种快速组织丧失疾病，严重影响了美属维尔京群岛(USVI)圣托马斯西南海岸附近的一处珊瑚礁。在过去的四年里，SCTLD一直在摧毁佛罗里达州东南部的珊瑚礁社区，最近在加勒比海周围的不同地区，包括墨西哥、牙买加和圣马丁，都有报道。维尔京群岛大学研究人员的快速调查认为，圣托马斯西南50平方公里的区域是疾病的初始发病区域，但可能会在美属维尔京群岛、英属维尔京群岛和波多黎各蔓延。这项研究进行了实验，以了解这种疾病如何影响珊瑚物种的免疫特征，并将美国西弗吉尼亚州的疾病样本与佛罗里达州的样本进行微生物学和生理学比较。它还研究了改变珊瑚群落的物种组成如何影响疾病的传播和影响。总体目标是建立一个模型，根据珊瑚物种组合预测多种疾病传播对珊瑚礁的影响。该项目对至少2名本科生、2名硕士研究生和3名博士生的研究培训做出了贡献，他们受益于交叉调查人员的指导。研究小组包括美属维尔京群岛和佛罗里达珊瑚疾病咨询委员会的代表，该委员会确保将研究结果迅速传达给这两个地区的管理机构。珊瑚疾病是对加勒比珊瑚礁系统的一个重大且日益严重的威胁。最近的研究结果表明，珊瑚物种的免疫特性可以预测疾病的抵抗力，从而预测在多物种珊瑚疾病下对珊瑚群落结构的影响。这种流行病在美属维尔京群岛的爆发提供了一个前所未有的机会，可以检验关于珊瑚抵抗力、耐受性和免疫特性对疾病传播的影响的假设，在疫情爆发的早期阶段，这可能会深刻改变加勒比海珊瑚礁的多样性。据推测，高度敏感物种的丰富决定了1)疾病在最初发病区域下游的礁石地点出现，以及2)疾病在礁石地点内的传播。此外，3)移走或处理高度敏感物种的珊瑚礁下游地点，所有易感珊瑚的免疫反应都较低，发病较晚，现场疾病传播较慢。为了验证这些假设，两个实验直接比较了物种对疾病暴露的反应，并测试了物种组合对珊瑚免疫功能和疾病传播的影响。这些实验的结果旨在提供一个可推广的模型，以根据珊瑚物种组合来预测多物种疾病传播对珊瑚礁的影响。该项目的成果包括将USVI疾病与佛罗里达SCTLD进行直接比较，以及更好地了解在多物种动物园早期，高度敏感的宿主物种的丰富如何影响疾病的传播。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Title: Predicting the Spread of Multi-Species Coral Disease Using Species Immune TraitsCoral reef ecosystems provide substantial economic resources to the societies of the United States Virgin Islands (USVI) and other US locations in the forms of tourism, fishing and coastal protection. However, reefs are among the most threatened marine environments, and coral disease is having a devastating impact on these valued systems. In early 2019, a multi-species rapid tissue loss disease matching the description of stony coral tissue loss disease (SCTLD) was found severely affecting a reef off the southwest coast of St. Thomas in the US Virgin Islands (USVI). SCTLD has been devastating coral reef communities in southeast Florida for the last four years, and was very recently reported from disparate areas around the Caribbean, including Mexico, Jamaica, and St. Martin. Rapid surveys by the investigators at the University of the Virgin Islands believe that a 50 km2 area southwest of St. Thomas is the initial incidence area of the disease, but will likely spread across the USVI, British Virgin Islands, and Puerto Rico. This study performs experiments to understand how this disease affects coral species immune traits and compares the microbiology and physiology of disease samples in the USVI to samples from Florida. It also examines how changing the species composition of a coral community affects the spread and impact of the disease. The overall aim is to produce a model to predict the impact of multi-species disease spread on reefs based on coral species assemblages. The project contributes to the research training of at least 2 undergraduates, 2 M.S. students, and 3 Ph.D. students, who benefit from cross-investigator mentoring. The research team includes representatives to the Coral Disease Advisory Committees for the USVI and Florida, which ensures rapid communication of findings to management bodies in both regions. Coral disease is a significant and increasing threat to Caribbean coral reef systems. Recent results demonstrate that coral species immune traits can predict disease resistance, and thus, forecast impacts to coral community structure, under multi-species coral disease. The onset of this epizootic in the USVI offers an unprecedented opportunity to test hypotheses about the impact of coral resistance, tolerance and immune traits on disease spread during the early stages of an outbreak that could profoundly change the diversity of Caribbean reefs. It is hypothesized that the abundance of highly susceptible species dictates 1) the onset of disease at reef sites downstream of the initial incidence area, and 2) the spread of disease within reef sites. Furthermore, 3) downstream reef sites where highly susceptible species are removed or treated show lower immune responses in all susceptible corals, later onset of disease, and slower within-site disease spread. To test these hypotheses, two experiments directly compare species responses to disease exposure and test the effect of species assemblage on coral immune function and disease spread. Results from these experiments aim to inform a generalizable model to predict the impact of multi-species disease spread on reefs based on coral species assemblages. Results of this project include direct comparison of the USVI disease to Florida SCTLD and a better understanding of how the abundance of highly susceptible host species impacts the spread of disease during the early onset of a multi-species panzootic.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.