Global Frog Decline

I've written on this topic before - but feel it's worth a revisit after I came across a graceful tree frog today.

Usually nocturnal, so seldom seen moving around during the heat of the day it gave me pause. Maybe it had been disturbed by a hunting animal (my guess would be a snake), or maybe it was compelled to re-locate thanks to the numerous green ants foraging around the elephant ear plant it was on. Possibly it had simply picked the wrong spot to snooze in and was getting a grilling from the sun ... who can say?.

Thing is though that as I was considering all of this I was struck by just how few frogs we've been seeing. And the more I thought about it the more I realised that in actuality, over the last decade or so that I have been observing frogs in N.Qld; their numbers have reduced dramatically.

Perhaps some sort of tipping point has been reached?

The first major review of Australian frogs was published in 1961 and listed 94 species. In the subsequent *45 years of research (*quote from 2006) that figure has more than doubled. Sadly, for the past 20 years there has also been an attrition which has now become extremely serious. This phenomenon has been called “declining frog populations”.

Frogs are sensitive to aquatic environmental pollution and it is mainly for this reason that their demise has attracted considerable concern. Frogs lay naked, unprotected eggs in fresh water. The eggs and tadpoles are therefore exposed to aquatic pollutants which either interferes with growth processes (thus causing abnormalities), or are so toxic that they will kill them. ^

As you may or may not be aware - frogs (and other amphibians) are true indicator species. Meaning their health or lack thereof is like an ecological barometer. Healthy environments = healthy frog populations. The very fact that these animals are still in decline should be worrying the living hell out of all of us.

It should be front page news (unfortunately there's no space left for news in the news, what with all those endless, daft bloody master chef/rules/reality clownathons).

So let me appeal to our most over-riding instinct: Self-preservation.

... the loss of frogs is particularly disturbing. The reason for this is that complex glands in frog skin secrete a wide variety of chemical compounds of benefit to human and animal medicine. These compounds include novel antibiotics, mosquito repellents, and even a glue which is being tested for its use in surgery.

Much of this work is being undertaken in Australia and does not require a single frog to be killed. If frog species disappear, the opportunity to search for other new secretions will disappear as well

Ya gotta wonder how many treatments or even cures are just waiting to be discovered?.

But we really shouldn't have to be manipulated into wanting our croaky little mates to be doing well - they should be valued simply on their own merit.

There is an excellent article on another significant threat to amphibians - here's an excerpt and link:

... among wildlife diseases, the chytrid fungus known as Batrachochytrium dendrobatidis, or Bd for short, is the most severe. The fungal disease, which affects frogs and salamanders, was first identified in 1998 following a series of mass amphibian die-offs in Australia.

Since then, Bd has spread to six continents and contributed to the severe decline or extinction of at least 200 amphibian species. Frogs and the chytrid fungus

Graceful tree frog (Litoria gracilenta)

A museum piece?

The trigger for Australian awareness was the extinction of the Gastric Brooding Frog, (Rheobatrachus silus) in southeast Queensland

Credit: Mike Tyler, 1973

The above pic is from an Australian Geographic post on the attempt to 'revive' the species using frozen genetic material. They succeeded in creating an embryo - however, it did not survive.

The article continues:

... the research highlights the need for Australia to develop a bank of genetic material so that if the technology proves itself, future species extinctions can be avoided.

Half of all amphibians are in decline and 30 per cent are faced with extinction, largely as a result of human activity, says Simon.

The results of the project were presented in the US on Friday at TED conference for researchers discussing the possibility of bringing other extinct species back, including the woolly mammoth, the moa and the dodo.

Grim isn't it?. It's almost as if we've admitted defeat and the best we can hope for is that in some indeterminate time in the future we'll be able to clone the wildlife we were unable to protect when they were alive.

This though begs the question - where are we going to put anything we 'revive'?. Special clone zoos?. Science labs?. Who knows, maybe Amazon will drone a clone right to your door?.

But hey, it may not be this bad. Could be that I've overdosed on dystopian Netflix doco's recently ...

And wouldn't you know it? Look who turned up at the back door - our old friend the Green Tree Frog (Litoria Caerulea).

... nice to see ya buddy

If you've got time, I'd be really interested in hearing from anyone else who has noticed a decline in their local amphibian populations ...

So with that in mind, take care - Paul.

If you'd like to check the Australian Species Profile and Threats Database for frogs you can start here:
Threats Database

Oh and just in case I've managed to bum you out completely - here's an article from Cracked (to remind us just how much we really don't know) Questions You Won't Believe Science Can't Answer