Over a quarter of Australia’s 219 frog species occur in the Wet Tropics region on the north-east coast of Queensland, an area of approximately 894,000 hectares between Townsville and Cooktown.
However frogs in these tropical rainforests are disappearing, especially from high altitude rainforests where a large diversity of frogs live and unique species occur on just a single mountain top.
Currently around 21 frog species are under threat, listed as Vulnerable, Rare or Endangered in Queensland by the Nature Conservation Act 1999. Some of these species have not been recorded in the wild for some years and may already be extinct.
Why frogs matter
Frogs and other amphibians profoundly enhance our lives and our world in countless ways. In addition to their intrinsic value as a beautiful part of nature, they offer many benefits to us:
They play an important role in the food web as both predator and prey, maintaining the delicate balance of nature. Where they are disappearing, detrimental effects are already being documented.
Amphibians eat pest insects, benefiting successful agriculture around the world and minimizing the spread of diseases, including malaria.
The skin of amphibians has substances that protect them from some microbes and viruses, offering possible medical cures for a variety of human diseases, including HIV and AIDS.
1. Pollution really gets under a frog’s skin
Beginning in the early 1980s, biologists began to realize that amphibians such as frogs are extremely sensitive to pollution and other environmental stresses.
Amphibians’ skin is highly permeable, allowing them to drink and breathe but at the same time this means they are exposed more directly to pollutants and environmental radiation. In addition, their eggs are laid in ponds and other water bodies, so they can absorb whatever chemical pollution may be present throughout their early developmental period. 
2. Evicted with nowhere to go
As frogs have complex life cycles, they require different environments for different stages of their lives and scientists agree that habitat loss, degradation and fragmentation will be the biggest threat to amphibians in the long run.
In Australia, current rates of land clearing are still among the highest in the world and dramatically adding to the decline in frog numbers as species struggle to find food, fresh water, suitable resting places and mates.
3. Climate change drying out ponds
Higher temperatures increase evaporation from and the drying out of frog breeding pools and as a result the deaths of tadpoles and frogs eggs. It is also likely that increases in temperature (drier conditions) could result in higher adult mortality, due to increased rates of internal water loss through their permeable skin.
4. Introduced and killing our wildlife
Domestic pets and feral animals are a major threat to our wildlife. In Australia the number of native animals killed by dogs and cats is estimated as high as 18 million native animals per year.
While domestic cats may be tame they are still natural predators and also threaten wildlife. It is estimated that cats kill 3.8 million native Australian animals each year, including frogs.
Feral pigs also impact on frog habitat. They dig up soil to find roots, shoots and worms and at the same time destroy vegetation and cause massive erosion and habitat loss around watercourses and throughout rainforests, the frogs’ home.
5. Disease spreading and unstoppable
The most immediate threat to frogs is a parasitic fungus called amphibian chytrid, a disease that is deadly to hundreds of amphibian species and has quickly spread from Africa across the planet over the past 30-40 years.
The disease is currently unstoppable and untreatable in the wild, even in protected areas. In the environments where it thrives, the fungus can kill 80 percent of native amphibians within months, leading to widespread amphibian extinctions.
The disease may also be exacerbated by climate change as warmer temperatures dry the moist areas where amphibians thrive, and cause stress that may lead to greater susceptibility to disease.
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