RUI: Beyond cleaning symbiosis: Ecology of

RUI：超越清洁共生：生态学

• 批准号: 1536794
• 负责人: Paul Sikkel
• 金额: $ 92.94万
• 依托单位: Arkansas State University Main Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2021-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1536794&HistoricalAwards=false
• 关键词: RUI; Beyond; cleaning; symbiosis; Ecology

Most research on the complex biological interactions that inhabit coral reefs has focused on larger organisms that are easily observed by divers. However, marine scientists are increasingly aware of the importance of the tiny organisms that make up the "smaller majority." This includes parasites, organisms that feed on other organisms without killing them, which may make up as many as 80% of the species on coral reefs. Among the most important parasitic organisms on coral reefs are gnathiid isopods, so-called 'ticks of the sea', that share many similarities with blood-feeding ticks and other arthropods on land. Like ticks and mosquitoes, gnathiids transmit malaria-like blood parasites. In high numbers, they can remove enough blood to kill adult fish, but even a single gnathiid can kill a juvenile fish. Thus, gnathiids may have a significant effect on coral reef communities through their effects on coral reef fishes. This project will use an integrative interdisciplinary approach involving field and laboratory observations and experiments, and molecular tools. In addition to contributing to our understanding of life in our oceans, this research will provide continued support for U.S. Doctoral and Masters students and will create valuable research opportunities for undergraduates from multiple institutions. The project will further build on the investigators existing relationships with resource managers, local divers, fishers, and boat operators, as well as K-12 schools and environmental education programs, and will contribute to local economies. A major goal of our outreach efforts will include an exhibit featuring our research at Coral World Ocean Park on St. Thomas, participation in Virgin Islands radio programs, and hosting high school students from South Carolina Governor's School.The overall goal this investigation is to understand the ecology of fish-parasite interactions on coral reef and associated ecosystems. This project focuses on fish-parasitic gnathiid isopods, the most common ectoparasites of coral reef fishes that are best known for their role in cleaning symbiosis, as the major food item of cleaner fishes. However, their abundance, host range, role as micropredator, disease vector, and potential prey item for other species, as well as their strong association with the benthos suggests the potential for much stronger community impacts. The goals for this project are to: 1) characterize the factors influencing local gnathiid isopod density by examining the role of fish-hosts, benthic cover, gnathiid predators including cleaners, and gnathiid conspecific attraction; 2) determine and quantify variation in host exploitation and the effects of gnathiid density on larval fish-host recruitment. To accomplish the first objective, the investigators will trap gnathiids from the substrate at sites in the Caribbean, Australia, and the Philippines. Variables associated with benthic habitat as well as local fish communities will be quantified and compared with local gnathiid abundance. Laboratory experiments will be conducted to determine the effects of different host species on gnathiid growth and reproduction and to determine the role of conspecific attraction in the formation of aggregations. Predators of gnathiids will be identified through examination of gut contents and through laboratory feeding studies. To accomplish the second objective, patterns of host-exploitation will be determined by DNA barcoding of blood meals from wild-caught gnathiids and results compared with the availability of different host species. To determine the effects of gnathiids on early life history stages of coral reef fishes, gnathiid abundance will be manipulated on small artificial patch reefs onto which newly-settled reef fishes will be transplanted.

大多数关于栖息在珊瑚礁上的复杂生物相互作用的研究都集中在潜水员容易观察到的更大的生物上。然而，海洋科学家越来越意识到构成“较小多数”的微小生物的重要性。这包括寄生虫，即以其他生物为食而不杀死它们的生物，它们可能占珊瑚礁上多达80%的物种。珊瑚礁上最重要的寄生生物是节肢等足目动物，也就是所谓的“海中的扁虱”，它们与陆地上以血液为食的扁虱和其他节肢动物有许多相似之处。像扁虱和蚊子一样，蚊虫传播类似疟疾的血液寄生虫。在数量较多的情况下，它们可以清除足够多的血液来杀死成鱼，但即使是一只爬行动物也可以杀死一条幼鱼。因此，珊瑚虫可能通过对珊瑚礁鱼类的影响而对珊瑚礁群落产生重大影响。这个项目将使用一种综合的跨学科方法，包括现场和实验室观察和实验，以及分子工具。除了有助于我们了解海洋中的生命外，这项研究还将为美国博士生和硕士研究生提供持续支持，并将为来自多个机构的本科生创造宝贵的研究机会。该项目将进一步加强调查人员与资源经理、当地潜水员、渔民和船只运营商以及K-12学校和环境教育项目的现有关系，并将为当地经济做出贡献。我们外展工作的一个主要目标将包括在圣托马斯的珊瑚世界海洋公园举办一次展览，展示我们在维京群岛广播节目中的研究，并接待南卡罗来纳州州长学校的高中生。这项调查的总体目标是了解珊瑚礁和相关生态系统上鱼类和寄生虫相互作用的生态学。该项目重点关注鱼类寄生的节肢等足目动物，这是珊瑚礁鱼类最常见的体外寄生虫，以其在清洁共生方面的作用而闻名，是清洁鱼类的主要食物项目。然而，它们的丰度、寄主范围、作为微型捕食者、疾病媒介和其他物种的潜在猎物的作用，以及它们与底栖动物的密切联系，表明它们可能会对群落产生更大的影响。该项目的目标是：1)通过研究鱼类宿主、底栖生物覆盖物、包括清洁剂在内的节肢动物捕食者和节节节肢动物同种吸引的作用来表征影响当地节肢动物等足类密度的因素；2)确定和量化宿主利用的变化以及节节节虫密度对幼鱼-宿主补充的影响。为了实现第一个目标，研究人员将在加勒比海、澳大利亚和菲律宾的地点从底物中捕获蚊虫。将对与底栖生境以及当地鱼类群落相关的变量进行量化，并与当地的节肢动物丰度进行比较。将进行实验室实验，以确定不同寄主物种对节肢动物生长和繁殖的影响，并确定同种吸引在聚集形成中的作用。将通过检查肠道内容物和实验室饲养研究来识别节肢动物的捕食者。为了实现第二个目标，将通过对野生捕获的蜘蛛血粉进行DNA条形码编码，并将结果与不同宿主物种的可用性进行比较，来确定宿主利用的模式。为了确定珊瑚虫对珊瑚礁鱼类早期生活史阶段的影响，将在小型人工斑块礁上操纵珊瑚虫的丰度，将新定居的珊瑚礁鱼移植到上面。