SGER: Investigating the Spread and Causes of Amphibian Declines in Tropical America

在1990年至1997年之间，PI观察到在中美洲山区两个偏远的受保护地点的河岸无尾猿数量突然和无法解释的下降。这些下降的原因尚不清楚，但根据五年多的个人观察、人口统计数据和对死青蛙的尸检结果（由D. E. Green）， PI假设这两次下降可能归因于两种微生物病原体：真菌和病毒。调查表明，这两个地点受到的影响与导致哥斯达黎加蒙特维德两栖动物大量死亡的是同一种病原体，过去10年来这三个地点两栖动物的连续消失证明了一种高度传染性病原体正在通过中美洲地峡传播。PI将提议组织一个多学科快速反应和评估小组，试图在两栖动物死亡这一明显的“前沿”之前跳跃。该小组将调查两栖动物群和环境的健康状况，以记录它们在衰退期间的变化。可能的成员包括爬虫学家、病理学家、毒理学家、内分泌学家、寄生虫学家和流行病学家。研究小组将以系统的方式调查这些地点，通过调查所有生命阶段，测量被认为导致或促成两栖动物数量下降的环境因素，并收集个体进行全面的医学诊断评估，来确定两栖动物数量下降的机制。该小组将通过对已经发生和预计会发生下降的高地地区进行调查，确定中美洲和南美洲这种下降的地理范围。

Lips 9807583 Between 1990-97 the PI has observed the sudden and unexplained decline of the riparian anurans at two remote, protected sites in montane Central America. Causes of these declines are unknown, but based on over five years of personal observations, demographic data, and results of autopsies on dead frogs (by D. E. Green), the PI hypothesizes that these two declines may be attributed to two microbial pathogens: a fungus, and a virus. The PI suggests that these two sites were affected by the same agent as that which decimated the amphibians of Monteverde, Costa Rica, and that the sequential disappearance of amphibians at these three sites over the past 10 years is evidence of a highly contagious pathogen moving through the Central American isthmus. The PI will propose to organize a multidisciplinary Rapid Response and Assessment Team that would attempt to jump ahead of this apparent "front" of amphibian mortality. The team would survey the health of both the amphibian fauna and the environment to document the changes in each during a decline. Likely members would include herpetologists, pathologists, toxicologists, and endocrinologists, parasitologists, and epidemiologists. The team would survey these sites in a systematic way to determine the mechanisms of amphibian declines by surveying all life stages, measuring environmental factors thought to cause or contribute to declines, and collecting individuals for full medical diagnostic evaluations. The team would determine the geographic extent of this decline in Central and South America by surveying select upland areas where declines have occurred, and where declines are expected to occur.