DISSERTATION RESEARCH: Amphibian Parasites and Immunity: Newts as a Model for Understanding Amphibian Disease Ecology

青蛙和火蜥蜴的种类在全球范围内正在减少，其中一些显然是由于新的或更严重的疾病的出现。虽然这些流行病的确切原因尚不清楚，但它们很可能受到人类引起的环境变化的影响，这些变化影响到两栖动物对病原体的暴露和易感性。依赖温度的免疫对两栖动物的疾病动态可能特别重要，导致在春季或变化的气候条件下增加感染的敏感性。本项目使用常见的温带蝾螈作为模式物种来研究：(1)两栖动物感染和免疫的季节性；(2)导致最近两栖动物灭绝所涉及的鱼尾类真菌暴发的因素；以及(3)构成Newt寄生虫群落的生态过程。捕获-标记-再捕获方法将与实验室和野外实验相结合，用于测试解释在空间和季节调查中观察到的纽特种群及其寄生虫模式的假说。这项研究将对季节温度波动对两栖动物免疫防御的影响、一种重要真菌病原体的传播动力学以及两栖寄生虫的群落生态提供见解。通过深入了解两栖动物疾病生态学的一般原理，研究两栖类动物的多种免疫参数和寄生虫种类将对我们理解人类引起的环境变化如何影响两栖动物种群的疾病动态产生更广泛的影响。该项目将支持一位博士生的学位论文研究。

Frog and salamander species are declining worldwide, some apparently due to the emergence of new or more severe diseases. While the precise causes of these epidemics are unclear, they are likely to be influenced by human-induced environmental changes affecting both exposure and susceptibility of amphibians to pathogens. Temperature-dependent immunity may be particularly important to disease dynamics in amphibians, leading to increased susceptibility to infection in springtime or under changing climatic conditions. This project uses the Red-spotted newt, a common temperate salamander, as a model species for studying: (1) seasonality in infection and immunity in amphibians, (2) factors leading to outbreaks of an Ichthyophonus-like fungus implicated in recent amphibian die-offs, and (3) ecological processes structuring the newt parasite community. Capture-mark-recapture methods coupled with lab and field experiments will be used to test hypotheses which explain patterns observed in spatial and seasonal surveys of newt populations and their parasites. This research will provide insights into the effects of seasonal temperature fluctuations on amphibian immune defenses, the transmission dynamics of an important fungal pathogen, and the community ecology of amphibian parasites. Studying multiple immune parameters and parasite species in newts will lead to a broader impact on our understanding of how human-induced environmental changes affect disease dynamics in amphibian populations, by providing insight into general principles of amphibian disease ecology. This project will support the dissertation research of a doctoral candidate.