I was fortunate enough to have the opportunity to speak with Mike Tyler in the early some time ago and questioned him about the disappearance of Rheobatracus silus. At that stage they were uncertain of the exact cause. However, Mike said that he felt it was clearly an environmental factor as the frogs had survived for a further three years in the laboratory i.e. in captivity.
As Geckphotographer says, it is definitely attributable to the Amphibian Chytrid Fungus. The amphibian declines and extinctions began in northern NSW / southern Qld and move northwards, chronologically, through areas of pristine rainforest containing fast flowing streams. The occurrence of the fungus has now been documented from those areas in which marked amphibian declines took place.
It is worth noting the over collection of Rheobatracus silus by pharmaceutical companies is not correct and is not considered as a contributing factor to the frog’s decline by those that have investigated what happened and should know.
The likelihood of discovery of a surviving population is not good given the very specific habitat requirements of these frogs, their correspondingly limited natural distribution and their demonstrated susceptibility to the fungus.
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