Quantifying the population-level cost of amphibian chytridiomycosis in a changing montane ecosystem

背景两栖动物壶菌病的流行对世界许多地区的生物群落和生态系统造成了严重的危害。我们的研究表明，Batrachochytrium dendrobatium（Bd）正在欧洲广泛引入。然而，我们还没有数据来确定这些引进对幼稚的，本地的，两栖动物物种和社区的多样性和动态的影响，在短，中，时间尺度。研究系统本研究将利用我们自2003年以来收集的伊比利亚数据集。我们调查了126个地点的助产士蟾蜍（Alytes obstricans），并确定了31个发生感染的地点。最值得注意的是，这项调查表明，Bd已被引入到比利牛斯山脉西部的一个小地区。自2007年以来，我们一直通过收集患病率、病原体基因型和死亡率数据来详细跟踪该地区的感染情况。学生将能够使用该数据集来评估关于生物和非生物驱动因素在调节无症状和有症状感染之间的宿主-病原体动态方面的相对作用的假设。通过建立在我们以前的工作，学生将有机会匹配感染和未感染的湖泊，跨越广泛的海拔高度。与此同时，他们将获得细粒度的气象变量以及受感染湖泊的死亡率数据。这将使学生能够测量在空间和时间尺度上归因于BD感染的死亡率。对协变量（生物和非生物）的分析将用于模拟受感染人群与未受感染人群的相对生存能力，我们对气候变化如何影响这些山脉的理解将用于制定未来的预测。该项目的合作伙伴（BRL）有着研究Bd的历史，可以追溯到病原体的最初发现，并且在减轻壶菌病的影响方面有一个全球推广计划。合作者（CNRS）在研究比利牛斯山脉Bd的出现方面发挥了关键作用，并且是RACE（Chytridiomycosis对欧洲两栖动物生物多样性的风险评估）的关键合作伙伴。该项目建立在TWJG和MCF之间强大的工作关系的基础上，已经产生了15篇出版物和目前共同持有的NERC赠款。他们还共同监督NERC学生对Bd的遗传学和毒力，其研究结果将被整合到这个博士项目。

Background The emerging panzootic of amphibian chytridiomycosis has had profound deleterious effects on communities and ecosystems in many areas of the world. Our research has shown that Batrachochytrium dendrobatidis (Bd) is being widely introduced across Europe. However, we do not yet have the data to ascertain the effects of these introductions on the diversity and dynamics of naïve, and native, amphibian species and communities across short, and medium-length, timescales. Study System This study will make use of an Iberian dataset that we have been collecting since 2003. We have surveyed midwive toads (Alytes obstetricans) in 126 sites, and have identified 31 where infection occurs. Most notably, this survey has shown that Bd has been introduced into a small region of the western Pyrenees. Within this region, we have been tracking infection in detail since 2007 by collecting prevalence, pathogen genotypes, and mortality data. The student will be able to use this dataset to evaluate hypotheses about the relative roles of biotic and abiotic drivers in modulating the host-pathogen dynamic between asymptomatic and symptomatic infection. By building upon our previous work, the student will have the opportunity to match infected and uninfected lakes that span a wide range of altitude. At the same time, they will have access to fine-grain meteorological variables as well as mortality data for infected lakes. This will allow the student to measure the amount of mortality that is attributable to Bd-infection across spatial and temporal scales. Analysis of the covariates (biotic and abiotic) will be used to model the relative viability of infected versus uninfected populations, and our understanding of how climate-change will effect these mountains will be used to develop future predictions. The project partner (ZSL) has a history of working on Bd that goes back to the original discovery of the pathogen, and whom have a global-outreach program in mitigating the effects of chytridiomycosis. The collaborators (CNRS) have a key role in studying the emergence of Bd in the Pyrenees and are key partners in RACE (Risk Assessment of Chytridiomycosis to European amphibian biodiversity). This project builds upon a strong working relationship between TWJG and MCF that has yielded 15 publications and a current co-held NERC grant. They also co-supervise a NERC student on the genetics and virulence of Bd, whose findings will be integrated into this PhD project.