Amphibians under threat

this is an article from a British paper the Guardian it shows is about the decline of amphibians across the world. i don't know if any of the other newspapers of the world have reported this

Farewell to the frog?

Alok Jha, science correspondent
Friday October 15, 2004
The Guardian

A third of the world's amphibian species are in danger of extinction, according to the first ever global survey of the animals. Scientists think that the mysterious collapse in numbers might be a warning that our environment may be in a worse state than we think - amphibians are known to be the most sensitive of all animals to subtle changes in their ecosystems.
There is also a new spectre that has come to haunt the frogs, toads, salamanders and newts that live in and out of water - a fungus that has already destroyed entire populations in many parts of the world and could spread to Britain.

Scientists have known since the 1980s that the many of the world's amphibian species are vanishing but the scale of decline revealed by the new survey, published today in Science, has stunned them. Nobody knows what is causing the devastation but it is likely to be loss of habitat to pollution, climate change and increasing competition with humans.

More than 500 scientists from more than 60 countries took part in the three-year Global Amphibian Assessment, a study of the world's 5,743 known amphibian species. One in three - a total of 1,856 species altogether - are threatened with extinction, they say. The latest count shows 122 amphibian species have become extinct in the past 20 years.

At the global level, scientists say that the drop in amphibian numbers could be an indicator of the poor state of our environment. "Amphibians feel the effects of water pollution, climate change before other forms of life including mankind," said Neil Cox, a programme officer with the joint World Conservation Union and Conservation International biodiversity assessment unit, which coordinated the survey. "They are the best indicators overall of environmental health largely because their porous skins allow for water transpiration and movement of chemicals."

But damage to the environmental is not the whole story. Many species have disappeared from pristine habitats that have suffered little environmental damage. "This is thought to be a response partly to outbreak of the disease chytridiomycosis," said Mr Cox.

The disease is caused by a fungus of the chytrid family called Batrachochytrium dendrobatidis and it infests the skin of adult amphibians and the mouth-parts of their larvae. "Amphibians drink through their skin and they also breathe through their skin, so anything that happens to their skin really screws them up," said Dr Matthew Fisher, a molecular epidemiologist at Imperial College London. "Tadpoles carry it but they're absolutely healthy. It's when they morph into little froglets that they die instantly - as soon as they hop out of the pond."

There is no practical treatment for the disease, which is concentrated mainly in Australia, North and Central America and the Caribbean, and it is spreading. The fungus has been implicated in the extinction of the Kihansi spray toad from Tanzania and, in Europe, it has been found infesting the common midwife toad.

There have been no confirmed cases of the disease in Britain, but it could be just a matter of time.

Thanks William. That article and many more like it that have appeared in the papers around the world since yesterday are based on the Global Amphibian Assessment that I posted about in a separate thread

(Message edited by TJ on October 15, 2004)

Interesting reading William, thanks for passing that on.

A link to an article about the subject: http://www.iucn.org/themes/ssc/programs/gaa/gaa_EN.htm

Greets
~Mark

Hopefully breeders will be able to combat the decline.

Tim: i saw your report, i thought that it could back yours up.

Ben: we can only hope that, but it will be hard to do anything about the disease.

anyone: in another report i read that manderin newts were used in traditional chinese medicine, is this true?

william, it is true, if you dig through the tylo forum there are pics of large quantites of dried tylos being sold on the chinese medicine market.

here is the picture: (from the "shanjing as food" post on the tylo board)



(Message edited by ira on October 15, 2004)

Because the newts are poisonous do you think they may have some affect on people's health. Not saying I support this, I think it's horrid.

William, now I see

Science magazine has also published a fairly detailed report drawing from the assessment, but I only have a hard copy of it...

Benjamin, there's the saying, "One man's elixir is another man's poison." Things that are considered "poisonous" by some people are used by others, in moderation, precisely because of the desirable effect they have on the human body. Toad-lickers and shroomers can testify to this

Cynops pyrrhogaster was once used by men to seduce (read: drug) women -- sort of an Oriental version of Spanish Fly . I'm sure consumption of Tylototriton has some effect the human body, though I have no idea if it can really cure anything...

Chytrid is treatable in amphibians via antifunglas but the problem is in the enviroment as the fungus can persist in the soil potentially for decades. The actual cause of death in chytrid infected amphibians is still unknown at this point (last I checked) but not all species are equally susceptiable to the various strains of the fungus. Atelopus in Central and South America are very susceptiable for another example. Chytrid has recently been documented in Asia and last I have heard has been located in every country where a serious search has looked for it.
The current origin theory is that it originated in Xenopus as Xenopus populations in the wild show chytrid infections and are not affected by the fungus. Xenopus as a carrier would explain the rapid dissemination of chytrid world wide as a lab animal and being used for a number of years in pregnancy testing. The water used to house Xenopus is then dumped into the wastewater stream allowing infection downstream.

Just some chytrid comments.

Ed

And to think of people saying that the fungus was merely a natural uncontrollable/preventable problem.