Growling Grass Frog colour and pattern variations

Although not usually quite as spectacular as the leucistic frog I wrote about in my previous blog entry, Growling Grass Frogs can be found in a large range of colours and patterns. They normally range from a bright, iridescent green, to a dull, dark brown and their patterns can be equally as variable, ranging from virtually no markings to quite intricate patterns of brown, green and gold. The frogs are a cream colour underneath and many exhibit a brilliant blue on the groin and thighs.

During my recent field season, I collected genetic samples from the frogs by taking a small section of the toe webbing on one of the back feet. This also served as a method for identifying frogs that were recaptures. I took a photo of every Growling Grass Frog I caught, which I then used to compare individual markings and identify who I had recaptured. This was quite straightforward for some frogs, however others were more challenging to identify. This is because each frog can change colour, depending on environmental conditions or mood, so one individual can change from a dull brown to an emerald green within a short period of time. Another really interesting observation (which further complicated identification) was that markings also changed over time as the frogs grew.

During my field work I’ve come across some particularly interesting markings on Growling Grass Frogs. One of my favourites is the ‘moustache frog’, which i’ve included in the pictures below.

Showing ‘greener’ variations

Olive to dark brown colour variations

Note the blue thigh

This individual had a blue markings down to its foot

A ‘typical’ quarry frog – very brown

Moustache frog!