Twenty years ago my garden and the street in which I live rang with the sound of frogs calling after dark - at times it was deafening and drowned out the sound of the television news presenter.
Frogs of different species were in my letterbox, in the garden trees, catching moths on the window sills, hopping about on my patio and frequently in the house.
No more.
Anyone living in urban areas of the NSW Northern Rivers region would be aware that fewer frog species and fewer numbers within those frog species have been part of garden, park and nature reserve landscapes over the last twenty years.
Loss of habitat due to land clearing, drainage or development, depredation by introduced species, over use of herbicides/pesticides by councils and homeowners, decease in available food sources and disease are taking their toll on local frog populations.
When one sees the scale writ large it is terrible to behold.......
The
Guardian, 29
March 2019:
A deadly disease that
wiped out global populations of amphibians led to the decline of 500 species in
the past 50 years, including 90 extinctions, scientists say.
A global research
effort, led by the Australian National University, has for the first time
quantified the worldwide impact of chytridiomycosis, or chytrid fungus, a
fungal disease that eats away at the skin of amphibians.
The disease was first
discovered in 1998 by researchers at James Cook University in Queensland
investigating the cause of mysterious, mass amphibian deaths.
Chytridiomycosis is
caused by two fungal species, both of which are likely to have originated in Asia,
and their spread has been facilitated by humans through activities such as the
legal and illegal pet trade.
Forty-two researchers
worked on the new study,
published in Science on Friday, which pinpoints the extent of the disease and
how devastating it has been for frog, toad and salamander species.
They found evidence that
at least 501 species had declined as a result of chytrid fungus and 90 of those
were presumed or confirmed extinct.
“The results are pretty
astounding” Benjamin Scheele, a research fellow at the ANU and the project’s
lead researcher, said.
“We’ve known that
chytrid is really bad for the better part of two decades but actually
researching and quantifying those declines, that’s what this study does.”
The scientists
identified declines in amphibian species in Europe, Africa, Central and South
America and Australia because of the disease.
Scheele said there were
no declines in Asia because species had evolved to be naturally resistant.
The impact of the
disease has been hardest in Central and South America and in eastern Australia,
where it flourishes in cool and moist conditions. It does not survive at
temperatures above 28C.
In Australia, chytrid
fungus is present in upland areas along the Great Dividing Range, down to the
Otways in Victoria, and the edges of South Australia and Tasmania.
It is also found in some
of the cooler mountain areas of Queensland.
Scheele said in Australia alone, there were 240 species
of amphibian, 40 of which the researchers believed had suffered population
declines as a result of chytrid fungus.
Seven of those 40 are believed to be extinct. One of
those is the mountain mistfrog, which was last
year added to a group of species the Australian government has been
assessing to determine whether it should be moved to the national list of extinct
wildlife.
Other species, including both the southern and northern
corroboree frog, have suffered because of chytrid fungus, but large-scale
captive breeding programs have worked to prevent their extinction..... [my
yellow highlighting]
