The Red-crowned toadlet

They may not be humongous mammals stomping around the Serengeti but our Red-crowned toadlets are also unusually rare. The first thing to remember though is that they are actually not toads…just tiny frogs with a confusing name.

I first came across the name “Red-crowned toadlet” when it appeared on a list of “vulnerable species” occupying bushland that would ultimately be bulldozed to create a nearby housing estate. Those various creatures threatened with extinction sadly failed to stand in the way of “progress”.

More recently, the Manly Vale Public school expansion involved clearing native vegetation at Manly Dam. The project’s “Environmental Impact Statement” declared the habitat “not suitable” for Red-crowned toadlets. Local citizen scientists, however, found and filmed a healthy population living right there. It didn’t save them though, NSW government’s “Biodiversity Offset scheme” allows developers to pay for “removing” such living inconveniences.

And thereby lies the problem. Red-crowned toadlets like to hang out in the very places that humans also desire. Often on the same sandstone ridges that provide Sydneysiders with such wonderful views.

Our little frog is less than 3 cm long (smaller than a cane toad tadpole). It’s dark brown and has a distinctive T-shaped reddish crown between its eyes (which have horizonal pupils). They also have orangey spots on their body and a striking marbled pattern on their stomachs whilst their fingers and toes are unwebbed.

The red colouring acts as a warning signal to potential predators as the frog is toxic to many birds and reptiles. But to some snakes and bandicoots they’re a juicy snack. Their own food source includes small insects, ants and termites.

This frog is found nowhere else on earth apart from small pockets of woodland in the Sydney basin. Even the slightest levels of pollution of their temporary creeks and soaks prevent them from breeding and minor disturbances can make a local population unviable. Unfortunately, they are in serious decline because of habitat degradation, illegal bush rock removal, hazard-reduction burns, weed invasion, climate change and the deadly chytrid fungus which attacks its skin and nervous system.

The toadlets rarely come out into the open. If there are any around, you’re more likely to hear them before you see them. Their call is a squelchy eeek eek sound, repeated at infrequent intervals which can be heard throughout the year. They tend to hang out in colonies of 20 to 30 individuals and just like with us humans, the females outlast the males. Some live for up to 15 years.

Unusually the red crowned toadlet is a terrestrial amphibian which means it has adapted to mostly survive away from water. During long periods of drought, they will bury themselves under the soil.

They breed in Spring and Summer after rain and lay about 20 jelly-like eggs under leaf litter or rocks which are then guarded by the male. The tadpoles finish their development when a storm comes, and they are washed into temporary pools where they swim free.

The Red-crowned toadlet is a “flagship” species for biodiversity on the Peninsula and is an important indicator of environmental health. We can help them by leaving rocks, logs and leaf litter alone and not straying from defined bush tracks.

To help identify the calls of frog species (and register your own discoveries) download the Frog ID app at frogid.net.au