Data from: Fishes alleviate the impacts of sediments on host corals

Abstract [Related Publication]:
Mutualisms play a critical role in ecological communities, however the importance and prevalence of mutualistic associations can be modified by external stressors. On coral reefs, elevated sediments are a major stressor, reducing the health of corals and damaging reef resilience. Here, we investigated the influence of sediment stress on the mutualistic relationship between small damselfishes (Dascyllus aruanus and Pomacentrus moluccensis) and their coral host (Pocillopora damicornis). In an aquaria experiment, corals were exposed to sedimentation rates of ~100 mg cm-2 day-1, with and without symbiont fish to test whether: (1) fishes influence the accumulation of sediments on coral hosts, and (2) fishes moderate partial colony mortality and/or condition. Colonies with fishes accumulated much less sediment compared to colonies without fishes, and this effect was strongest for colonies with D. aruanus (five-fold less sediment than controls) as opposed to P. moluccensis (two-fold less sediment than controls). Colonies with symbiont fishes also had up to 10-fold less sediment-induced partial mortality, as well as higher chlorophyll and protein concentrations. These results demonstrate that fish mutualisms vary in the strength of their benefits and indicates that some mutualistic or facilitative interactions might become more important for species health and resilience as stress levels increase.
Methods [Dryad]:

Datasets were collected through a combination of field and aquaria experiments on fish behaviour and coral physiology.

Usage Notes [Dryad]:

Partial colony mortality values for corals in the sediment aquaria experiment: The "colonymortality.csv" data file includes the proportion of the whole colony, P. damicornis, partial mortality at the end of the sediment experiment (28 days treatment exposure). For every coral colony, the sediment and fish treatments are listed, as well as the proportion of colony mortality (propmortality), at the "END" of the experiment. Note that a very small constant (0.001) was added to every colony's proportion mortality, to allow for analysis using a beta regression model (binomial distribution, bounded between 0 and 1).
Tissue values (protein and tissue biomass) sediment aquaria experiment: The "sedaqu.csv" datafile contains the proportion of colony mortality (whole colony) and tissue components of total proteins (protein), and tissue biomass (afdw) of the sample P. damicornis fragments sampled at the beginning ("START" - day 0 after a week of acclimation) and "END" (28 days of treatment exposure) of the sediment experiment in aquaria. For every coral, the phase of the experiment and sediment and fish treatments are listed. All values in the protein and afdw data are expressed per cm2 of surface area.
Chlorophyll tissue components and values for sediment aquaria experiment: The "sedchl.csv" datafile contains the data on the total chlorophyll (A and C2) of the sample P. damicornis fragments sampled at the beginning ("START" - day 0 after a week of acclimation) and "END" (28 days of treatment exposure) of the sediment experiment in aquaria. For every coral, the phase of the experiment and sediment and fish treatments are listed. All values in the chlorophyll data are expressed per cm2 of surface area. Additional information regarding the different chlorophyll components (A and C2) are included in the data sheet.
Supplementary data on Sediment Traps: The "sedtrapsgrain.csv" data file contains supplementary data on the total sediment and sediment grain sizes (small (

摘要 [相关出版物]：
互利共生（mutualism）在生态群落中发挥关键作用，然而互利共生关系的重要性与普遍程度会受到外界胁迫因子的调控。在珊瑚礁（coral reef）生态系统中，过量沉积物是一类主要胁迫因子，会降低珊瑚健康水平并破坏礁体恢复力。本研究探讨了沉积物胁迫对小型雀鲷（宅泥鱼*Dascyllus aruanus*、摩鹿加雀鲷*Pomacentrus moluccensis*）与其珊瑚宿主（杯形珊瑚*Pocillopora damicornis*）之间互利共生关系的影响。
本研究设置水族箱实验（aquaria experiment），将珊瑚分别置于有/无共生鱼类共存的环境中，沉积物沉积速率设置为约100 mg·cm⁻²·d⁻¹，以此验证两个假说：（1）鱼类是否会影响珊瑚宿主表面的沉积物累积量；（2）鱼类是否能够缓解珊瑚群落的部分死亡率或改善珊瑚健康状态。
与无共生鱼类的珊瑚群落相比，有鱼类共存的群落沉积物累积量显著更低，其中宅泥鱼组的效果最为显著（沉积物累积量仅为对照组的1/5），摩鹿加雀鲷组次之（为对照组的1/2）。有共生鱼类的珊瑚群落，沉积物诱导的部分群落死亡率最高可降低至原来的1/10，同时叶绿素与蛋白质浓度也更高。
本研究结果表明，鱼类介导的互利共生关系其收益强度存在差异，同时也暗示随着胁迫水平升高，部分互利或易化交互作用对物种健康与恢复力的重要性可能会显著提升。
方法 [Dryad]：
本数据集通过野外与水族箱联合实验采集所得，实验内容涵盖鱼类行为与珊瑚生理学相关指标。
使用说明 [Dryad]：
沉积物水族箱实验中的珊瑚部分群落死亡率数据：文件"colonymortality.csv"包含了沉积物实验结束时（28天胁迫暴露后）杯形珊瑚*Pocillopora damicornis*全群落的部分死亡率占比。数据中记录了每一个珊瑚群落的沉积物与鱼类处理组信息，以及实验结束时的群落死亡率占比（propmortality）。需注意，为适配β回归模型（beta regression model，二项分布（binomial distribution），取值范围限定为0~1）的分析需求，所有群落的死亡率占比均加入了极小常数0.001。
沉积物水族箱实验的组织指标（蛋白质与组织生物量）数据：文件"sedaqu.csv"包含了在沉积物水族箱实验初始阶段（"START"——驯化1周后第0天）与实验结束时（"END"——28天胁迫暴露后）采集的杯形珊瑚样本的群落全死亡率占比、总蛋白质含量（protein）与组织生物量（afdw）。数据中记录了每一个珊瑚样本的实验阶段、沉积物与鱼类处理组信息。所有蛋白质与afdw指标均以每平方厘米表面积为单位进行归一化表达。
沉积物水族箱实验的叶绿素组织组分与指标数据：文件"sedchl.csv"包含了在沉积物水族箱实验初始阶段（"START"——驯化1周后第0天）与实验结束时（"END"——28天胁迫暴露后）采集的杯形珊瑚样本的总叶绿素（叶绿素A与C2）含量数据。数据中记录了每一个珊瑚样本的实验阶段、沉积物与鱼类处理组信息。所有叶绿素指标均以每平方厘米表面积为单位进行归一化表达。数据集中还附带了不同叶绿素组分（A与C2）的详细说明。
沉积物捕集器补充数据：文件"sedtrapsgrain.csv"包含了总沉积物含量与沉积物粒径（小型（