Saturday, December 30, 2006

The amazing camouflage of Crinia georgiana

Not only can't you find them, but they also call like a duck!

I refer to a small frog called the Quacking Frog or Tschudi's Froglet, Crinia georgiana.

Does it really sound like a duck? Well listen here:
(Recording compliments of Frogs Australia Networks)

The Quacking Frog grows to 4 cm in length (although usually around 3 cm) and is very common in shallow freshwater swamps and rocky outcrops from Esperance (600 km SSE of Perth), to Gingin (around 100 km north of Perth). During their breeding season (winter to early spring), their calls are deafening, but try and find one and you either have to be very good or very lucky.

In this photo there is an adult frog making up most of the frame. Can you see it?

I dare say you could find it well enough after I had told you it was there, but if you were casually looking at the same area, most would not. Not only do the colors blend beautifully into the background, but also the body comprises many bumps, skin folds and wavy lines. This disguises the outline of the frog, providing an almost perfect camouflage.

Take the frog away from its natural environment and it has quite distinctive coloration. The red around the groin is typical to adults of both sexes, plus the golden patch on the upper eyelids (in some areas apparently, the eyelids can be red). These are the most distinctive recognition features.

Quacking Frog, Crinia georgiana

Just look at the bumps on this fellow!


And the skin folds and wavy lines on this one! That golden blotch on its flank can also be white.


This Quacking Frog is not impressed by being picked up, but you can see more clearly the golden patches above the eyes and the very granular belly.


So because frogs can't always be seen, to discover the secrets of your bush, you may have to visit in the evening (during the mating season) and just listen. Often there are so many calls from different species, it can be difficult to identify them all, but this is still the best way to ascertain the number of frog species in your area.
Frogs are not only very cute, but are also an important part of the ecosystem, so look after them by protecting their habitat. However do take the kids and enjoy the educational experience of frogging on a pleasant mild evening, only make sure you leave your discoveries where you find them.


6 comments:

Anonymous said...

Not the prettiest frog I've ever seen, but definitely cute in it's own way.....especially that last picture.

I think it's the eyes that make frogs such endearing creatures.

It's camouflage is amazing. If I had seen a wrinkled up froggie like that I would have been tempted to offer it a good feed :)

Great stuff !

hv

Anonymous said...

>>>"Not only can't you find them, but they also call like a duck!"<<<

To think ourselves ever so more clever than animals is completely unwarranted hubris!! As to the camouflage, it could teach the army a thing or two on uniform design.

And anyway, when I see a frog, I just simply go to water, they are just sooooooooooo cute - , I'll kiss 'em for free, without the promise of becoming a princess.

You speak of protecting their habitat - at the risk of sounding stupid: how can *I* do that?

Anonymous said...

PS: Not really nature, but....

There is a cute little poem by Germany's greatest poet, Johann Wolfgang von Goethe, about Frogs which I'm tempted to post here. It's pretty unenlightened as far as wild-life goes, (it was written in 1821 when froggies still had a bad press) and spouts the quaint old-fashioned moral of "promises will be broken". It tells the story of how, one winter, when all the little froggies were locked in under the frozen lake, they promised, that - if they were ever let out again of this icy prison, they would not "croak" anymore, but sing like nightingales.

When the spring thaw finally came, and they got back to the warming surface, they forgot their promise and croaked away as loudly and happily as before.

Here is how it looks in its original language (German):



Die Frösche

Ein großer Teich war zugefroren;
Die Fröschlein, in der Tiefe verloren,
Durften nicht ferner quaken noch springen,
Versprachen sich aber im halben Traum,
Fänden sie nur da oben Raum,
Wie Nachtigallen wollten sie singen.
Der Tauwind kam, das Eis zerschmolz,
Nun ruderten sie und landeten stolz
Und saßen am Ufer weit und breit
Und - quakten wie for alter Zeit.

and here is a (not very literal) translation, unfortunately I cannot source the translator:

Frogs

A POOL was once congeal'd with frost;
The frogs, in its deep waters lost,
No longer dared to croak or spring;
But promised, being half asleep,
If suffer'd to the air to creep,
As very nightingales to sing.
A thaw dissolved the ice so strong,--
They proudly steer'd themselves along,
When landed, squatted on the shore,
And croak'd as loudly as before.

WA said...

Hi MissAnthropy, thanks again for your interest. Frogs are beautiful animals and such an important part of our environment. They are also an indicator of the health of our wetter habitats.

So how do we protect their habitat, I think like most things connected with wildlife, simply respect! We do not respect habitat when we knock it down, fill it in, drain or pollute it, because what we are doing is more than destroying a wetland, we are destroying an entire ecosystem. Plus the froggies will sing you love songs for your efforts! :)

Anonymous said...

Nice work again Jack. What a master of disguise this fella is. I looked up Crinia in my copy of Cogger's Reptiles and Amphibians of Australia and I notice that the 5 WA species all live in the south-west. If I don't learn anything else today, at least I now know theres a frog that quacks!!! Warm Regards Woollybutt (Peter)

WA said...

Thanks Woollybutt, pleased you enjoyed it.