Stunning blue-skinned frog is a rare genetic mutant

A rare blue frog found in the Kimberley region of Western Australia has stunned researchers, who say the unusual colouring is probably due to a genetic mutation causing it to lose certain skin pigments.

As its name suggests, the magnificent tree frog (Litoria splendida) is already a spectacular animal, so when Jake Barker at the Australian Wildlife Conservancy’s Charnley River-Artesian Range Wildlife Sanctuary saw a bright blue specimen on a bench in a workshop in April, he was shocked.

The amphibians are normally a vibrant green, which is a common colour for tree frogs and is thought to camouflage them.

“I knew as soon as I saw it that it was rare,” says Barker. “It’s not often that you get to see a blue frog.” It has been seen a number of times since, but won’t be captured for research, he says.

“It’s far too pretty and far too unique and it would be a pity to take it away from its natural habitat,” says Barker. “We’ll leave it to live out its days and hopefully get to see it many more times in the future.”

Jodi Rowley at the Australian Museum in Sydney says the animal may be the “most beautiful, aberrant-coloured frog” that she has ever seen. “And I have seen tens of thousands of frogs.”

From the photos she has seen, Rowley says the frog is at least 2 to 3 years old. The species may live to be 20 years old, so the blue individual is likely to be around for a while unless caught by a predator.

She says frogs’ skin colour is determined by the combination of three chemicals – melanophores, which provide blacks and browns; xanthophores, which provide yellow pigments; and iridophores, which reflect blue colours. Normally, the yellows and blues combine to make green, but it is thought the new blue frog has a mutation that means it is missing the yellow pigments and the blue dominates.

“Blue is probably a bit more obvious to predators,” says Rowley, “which is why we don’t see many blue frogs.”