真菌生生不息 黃腿山蛙難倖免 | 台灣環境資訊協會-環境資訊中心

真菌生生不息 黃腿山蛙難倖免

2007年08月14日
摘譯自2007年8月9日ENS美國,加州,柏克萊報導;丁秋仁編譯;蔡麗伶審校

黃腿山蛙(圖片來源: UC Berkeley)據一份基因研究報告發現,一種具高威脅性的真菌可藉由交配繁殖來傳播,使得現在美國加州內華達山區黃腿山蛙的蹤跡遍地難尋,也讓使其脫離絕種險境的工作更為困難。

黃腿山蛙往昔是內華達山區為數最多的兩棲類生物,但是過去30年來,上萬隻山蛙卻於數百處棲地死亡。

研究顯示,真菌對黃腿山蛙帶來的威脅性遠高於外來魚群的侵害,因為該生菌具有遠距離傳播能力,且可經由生物的交配行為長存於環境之中。

研究召集人摩根(Jess Morgan)指出,人類在不經意的情況下也會幫助真菌傳播,鞋底或汽車輪胎中的泥沙皆會潛藏孢子,因此其生長不受距離限制。此外,孢子同樣可能透過鳥類挾帶,將活動範圍擴展至山區。

真菌究竟如何造成蛙類死亡尚未有一定的解釋,不過大多數的科學家相信,是因為這些被感染的兩棲生物皮膚吸收水分的功能受到破壞所致。

Persistent Fungus Key to Sierra Nevada Frog Deaths
BERKELEY, California, August 9, 2007 (ENS)

A deadly fungus that has wiped out mountain yellow-legged frogs across California's Sierra Nevada can spread by sexual reproduction, complicating efforts to save the frogs from extinction, finds a new genetic analysis.

Once the most abundant amphibian in the Sierra Nevada, tens of thousands of mountain yellow-legged frogs have died at hundreds of sites over the past 30 years.

The study suggests that the fungus played a bigger role than the non-native fish because of its ability to spread over long distances and persist in the environment through sexual reproduction.

The fungus can be spread by people who transfer the spores around the world in dirt on shoes or car tires, warns the study's lead author Jess Morgan. Spores also can be carried across mountain ranges by birds.

Exactly how this fungus kills the frogs it infects is still unclear, but most scientists believe it disrupts the skin's ability to absorb water.

全文及圖片詳見ENS