Moaning Frog

AmphibianAustralia

11 Nov

Heleioporus eyrei

The moaning frog is named for its call, which sounds like a slow and drawn-out moan. This burrowing frog is native to southwestern Western Australia, where its calls can keep people up at night — it's recommended to gently flood the frog's burrow each night until the moaning male moves on.

Ribbit, Quak, Kero Kero

What does a frog sound like? If you learned English growing up, you were probably taught that a frog goes "ribbit" or "croak". You might expect a frog to go "cra cra" if you're Italian. In German, a frog goes "quak" like a duck, in Hungarian it's "brekeke", in Polish it's "kum kum", and in Japanese it's "kero kero". The onomatopoeic interpretations of a frog's voice are many and varied, however, few would describe a frog as "moaning". But that's exactly what one anuran from Australia sounds like.

Moaning Frogs

Autumn in southwest Western Australia (beginning in March) brings the first heavy rains, and with the downpour, a chorus of lustful, moaning frogs. Beneath the soft sands of swamps, inside moist burrows, sit hundreds of rotund little frogs — measuring no longer than 6.6 centimetres (2.6 in) — with portly bodies, stout limbs, and bulbous eyes. As night falls, one frog begins to call; a long, drawn-out, mournful-sounding moan. Then another joins in. And another, until an entire choir of frogs sings from beneath the ground. They fill the night air with their echoing moans, their haunting song, almost like the howling of wolves.

The male frogs are the "moaners". They call for only about one month out of the year as the first rains arrive, trying to attract females to their burrows. While the males advertise themselves from under the soil, the females hop about in the dark, searching for the most alluring moaner. Once a female chooses a male, she enters his burrow, crawls down to the moist soil at the very bottom, and deposits her egg mass (as many as 300 eggs) before leaving — a fairytale love story this is not. Fertilized by the male, this foamy, white mass of eggs will eventually turn into hundreds of wriggling tadpoles.

Ideally, a male's burrow is dug in a low-lying area so that the heavy rains flood his underground lair and provide for his aquatic progeny a way to escape. The tadpoles — each some 5 cm (2 in) long and coloured black and gold — writhe in their foamy nurseries until freed by the flood waters. They then swim up to the surface, leaving the underworld and hopefully finding their way to a larger body of water where they'll hide and feed for 2 to 3 months until they can metamorphose into adult frogs.

Beating the Heat

Summertime in southwestern Australia is sunny, hot, and arid. The streaming rainwaters have long dried up and the surviving tadpoles are now frogs mottled in greys and browns. They hop away from their drying birthplaces, dispersing into the surrounding bushland where they'll hunt for insects, spiders, worms and snails. But, if the sun and heat become too much for their sensitive amphibian skins, they might return to their subterranean habits, burying themselves beneath moist soil and going dormant through the worst of the summer.

Several frog species can weather hot and dry conditions through estivation — a torpor or dormancy in which metabolic activity is slowed — including the ornate horned frog of South America, the African bullfrog, and the striped burrowing frog of northeastern Australia. And while it makes sense for a burrowing frog, living in the hot and arid Australian bush, to estivate during the summer months, as of now, there's not enough evidence to conclude that the moaning frog is an estivating frog.

A Froggy Choir Down Under

For such small animals, frogs can be impressively loud — no doubt urged on by evolution, with the loudest males often wooing the most females. Mostly, moaning frogs don't settle near humans. They'll pass through a garden or visit a pond to catch some grub, and then keep hopping along; dopey-looking but charming little visitors. But people living near wetland areas, the breeding stages for these anurans, are liable to have a different impression of these frogs. A month of moaning and mating for the frogs can be a month of sleepless nights for the frog's neighbours. How does one deal with the ceaseless wailing of a horny male? Well, if a moaner takes up residence near your home, you can locate his burrow with a flashlight, then use a bucket or water hose to gently flood his burrow — it might take a few nights of repeated flooding before he gets the message and decides to move on.

But the moaning frog isn't the only bellower Down Under. Western Australia is replete with an entire orchestra of vocalising amphibians. There's a humming frog that hums and trills and a ticking frog that concludes its calls with a 'tk...tk...tk'. A quacking frog that quacks like a duck and a hooting frog that hoots like an owl. A chattering rock frog that croaks in Morse code and a bilingual froglet with a distinct two-part call. There's a wailing frog, a whooping frog, and a squelching frog. It's a wonder that anyone in Western Australia gets any sleep at night.

A humming frog (*Neobatrachus pelobatoides*).

A hooting frog (*Heleioporus barycragus*).

A whooping frog (*Heleioporus inornatus*).

**Where Does It Live?**

⛰️ Swampy areas with soft sands and surrounding bushlands.
📍 South-western Western Australia.

‘Least Concern’ as of 21 May, 2021.

IUCN

Size // Small
Length // Up to 6.6 cm (2.6 in)
Weight // N/A
Activity: Nocturnal 🌙
Lifestyle: Solitary 👤
Lifespan: N/A
Diet: Omnivore
Favorite Food: Small bugs, spiders, and worms 🐛
Class: Amphibia
Order: Anura
Family: Limnodynastidae
Genus: Heleioporus
Species: H. eyrei

The male frogs are the moaners — they sit in burrows beneath the sandy soil and moan into the night, yearning for the attention of a female.

An entire choir of moaning frogs sounds weirdly eerie; almost like the distant howling of wolves in the night.

These frogs only moan for about one month out of the year, beginning in March with the first heavy rains.

Females hop around above ground, listening for the best moan. Having chosen a mate, a female enters his burrow, deposits a mass of up to 300 eggs at the bottom, and then leaves — not being one for romance. The male then fertilises the eggs.

When rainwater floods the burrow, the eggs hatch into black-and-gold tadpoles, each some 5 centimetres (2 in) long — as they metamorphose into tailless and portly adults, the largest females will grow no larger than 6.6 cm (2.6 in).

During the austral summer, when the land is hot and dry, these frogs leave the desiccated marshlands to hop around in the bush — hunting for insects, spiders, worms and snails.

Being a burrowing frog, it's speculated that this species buries itself in moist soil and estivates — entering a state of dormancy in which metabolism is lowered — through the worst of the summer, but there isn't any conclusive evidence of this yet.

Although moaning frogs rarely settle near humans, a misplaced and horny male in the backyard can mean a month of nightly moaning. If a male settles near your home, it's recommended that you gently flood his burrow with water for a few nights until he decides to move on.

Moaning frogs aren't the only rowdy frogs Down Under. Western Australia hosts an entire parade of moaners, hummers, and wailers. A few of these vocal amphibians include the quacking frog, whooping frog, chattering rock frog, humming frog, squelching frog, and bilingual frog.