Nowakowski A Justin, Whitfield Steven M, Eskew Evan A, Thompson Michelle E, Rose Jonathan P, Caraballo Benjamin L, Kerby Jacob L, Donnelly Maureen A, Todd Brian D
Department of Wildlife, Fish, and Conservation Biology, University of California, Davis, One Shields Ave., Davis, CA, 95616, USA.
Conservation and Research Department, Zoo Miami, Miami, FL, 33177, USA.
Ecol Lett. 2016 Sep;19(9):1051-61. doi: 10.1111/ele.12641. Epub 2016 Jun 24.
The fungal pathogen Batrachochytrium dendrobatidis (Bd) has caused the greatest known wildlife pandemic, infecting over 500 amphibian species. It remains unclear why some host species decline from disease-related mortality whereas others persist. We introduce a conceptual model that predicts that infection risk in ectotherms will decrease as the difference between host and pathogen environmental tolerances (i.e. tolerance mismatch) increases. We test this prediction using both local-scale data from Costa Rica and global analyses of over 11 000 Bd infection assays. We find that infection prevalence decreases with increasing thermal tolerance mismatch and with increasing host tolerance of habitat modification. The relationship between environmental tolerance mismatches and Bd infection prevalence is generalisable across multiple amphibian families and spatial scales, and the magnitude of the tolerance mismatch effect depends on environmental context. These findings may help explain patterns of amphibian declines driven by a global wildlife pandemic.
真菌病原体蛙壶菌（Batrachochytrium dendrobatidis，简称Bd）引发了已知规模最大的野生动物疫情，感染了500多种两栖动物。目前尚不清楚为何有些宿主物种会因疾病相关的死亡率而减少，而其他物种却能存活下来。我们引入了一个概念模型，该模型预测，随着宿主与病原体环境耐受性之间的差异（即耐受性不匹配）增加，变温动物的感染风险将会降低。我们利用来自哥斯达黎加的局部尺度数据以及对超过11000次Bd感染试验的全球分析来检验这一预测。我们发现，感染率会随着热耐受性不匹配的增加以及宿主对栖息地改造的耐受性增加而降低。环境耐受性不匹配与Bd感染率之间的关系在多个两栖动物科和空间尺度上具有普遍性，并且耐受性不匹配效应的大小取决于环境背景。这些发现可能有助于解释由全球野生动物疫情导致的两栖动物数量下降模式。
