Amphibian Disease Dynamics in a Fragmented Landscape

描述(申请人提供)：新鉴定的真菌病原菌， Batrachochytrium，最近被认为是导致 世界各地的两栖动物。我们的目标是确定壶菌病的起源( 由巴氏杆菌引起的疾病)，并了解人类如何 环境变化影响其流行和传播。我们的研究将 特别关注巴氏杆菌与 山地黄腿蛙(Rana Muscoa)，曾是我国常见的两栖动物 加利福尼亚州的内华达山脉。因此，蝴蝶是一种理想的研究宿主。 尽管种群数量减少了，但仍然很常见，可以用于实验， 而且人群受到旋毛菌病感染的强烈影响。和以前一样 在世界各地，内华达山脉的两栖动物是 承受着越来越多的人为应激源，包括 外来物种引进、栖息地碎片化和化学污染物 这些可能会改变疾病的流行和传播。将团队与 病原真菌、流行病学、两栖动物生态学、种群方面的专业知识 遗传学，统计和机械建模，我们的具体目标 目的是：1)描述巴氏杆菌的来源，以确定其 内华达山脉的两栖动物协会代表了一个古老的协会 或最近这种真菌扩展到以前未感染的青蛙中；2) 描述感染和传播对青蛙种群动态的影响 从现有的4500个数据库中确定的地点的临时复查 内华达山脉的水体；3)开发统计模型来描述 外来鱼类、栖息地碎片化和风媒的影响 农业污染物对青蛙和棘球菌病分布的影响； 以及4)开发详细的机制模型来预测可能的影响 不同的生物机制(包括自然和人为)对 旋毛菌病的发病率、空间分布和持久性，以及 预测该病对R.R.丰度和动态的影响。 番茄酱。考虑到对动物种群中疾病的研究很少 我们的研究结果将为疾病的研究提供重要的见解 其他系统的动态，并帮助努力保护生物多样性 面对新出现的传染病。

DESCRIPTION (provided by applicant): The newly identified fungal pathogen, Batrachochytrium, has recently been implicated as causing the decline of amphibians worldwide. We aim to determine the origin of chytridiomycosis (the disease caused by Batrachochytrium), and understand how anthropogenic environmental changes influence its prevalence and spread. Our research will focus specifically on the relationship between Batrachochytrium and the mountain yellow-legged frog (Rana muscosa), a once-common amphibian in California's Sierra Nevada mountains. R. muscosa is an ideal study host as it is still common enough despite population declines to be used in experiments, and populations are strongly influenced by chytridiomycosis infection. As with animal populations throughout the world, amphibians in the Sierra Nevada are being subjected to an increasing array of anthropogenic stressors including exotic species introductions, habitat fragmentation, and chemical contaminants and these may change the prevalence and spread of disease. Using a team with expertise in pathogenic fungi, epidemiology, amphibian ecology, population genetics, and statistical and mechanistic modeling, our specific objectives are to: 1) describe the origin of Batrachochytrium to determine whether its association with amphibians in the Sierra Nevada represents an old association or a recent expansion of the fungus into previously uninfected frogs; 2) describe the effect of infection and spread on frog population dynamics using temporal resurveys of sites identified from an existing database of 4,500 water bodies in the Sierra Nevada; 3) develop statistical models to describe the effect of nonnative fish, habitat fragmentation, and windborne agricultural contaminants on the distribution of frogs and chytridiomycosis; and 4) develop detailed mechanistic models to predict the likely effects of various biological mechanisms (both natural and anthropogenic) on the incidence, spatial distribution, and persistence of chytridiomycosis, and to predict the impact of this disease on the abundance and dynamics of R. muscosa. Given the paucity of studies of disease in animal populations in the wild, the results of our study will provide important insights into disease dynamics in other systems, and aid in efforts to protect biodiversity in the face of emerging infectious diseases.