Clicks, bonks and dripping taps: listen to the calls of 6 frogs out and about this summer

The banjo frog, Limnodynastes dumerilii
Jodi Rowley, Author provided

Jodi Rowley, Australian Museum

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Frog calls are iconic sounds of summer in Australia. There are more than 240 species native to Australia, almost all of which are found nowhere else on Earth.

While some of Australia’s frog species prefer the cooler months, spring and summer are the best times to see and hear the majority of them. This is particularly true in tropical Australia, where most frog species only emerge from their hiding places in the wet season, filling summer nights with their choruses.

Most of us will hear frogs before we see them. In all Australian frog species, male frogs call to attract female frogs to mate with. Each species has a unique advertisement call, so you don’t need to see a frog to identify it.

Males typically call from near water bodies, where they hope to breed, and call mostly at night, preferring to shelter in the heat of the day. As a result, the best place to encounter frogs is near a water body such as a pond, creek or wetland, and the best time is after dark.

This article contains recordings of six unique frog calls. Depending where you live, you might just hear one on a quiet, summer night. But first, let’s explore why frogs are so important to our ecosystems.

Read more:
Australians recorded frog calls on their smartphones after the bushfires – and the results are remarkable

From rainforests to deserts

Frogs are exquisitely adapted to almost all kinds of habitats in Australia, from rainforests to deserts. In some of the wettest forests, some frogs such as the northern ornate nursery frog (Cophixalus ornatus) have done away with the need for tadpoles, developing into tiny frogs in the egg.

The stonemason toadlet, Uperoleia lithomoda
Jodi Rowley, Author provided

In the driest parts of Australia, where it doesn’t rain for months at a time, frog species such as the eastern water-holding frog (Cyclorana platycephala) spend most of their lives underground. These frogs are protected from dehydration by a “cocoon” of their own skin and skin secretions. They only pop above the surface when it’s wet enough for them to breed in the flood waters.

While many species are common, more than 30 are threatened with extinction. On top of that, we’ve already lost at least four species — part of out natural heritage, gone forever.

The major frog threats are disease (particularly chytridiomycosis, caused by the amphibian chytrid fungus), habitat loss and modification, introduced species and climate change.

We should care that our frogs are disappearing, as they are an important part of healthy ecosystems. Frogs are major consumers of invertebrates, and are also eaten by a wide array of predators including fish, birds and mammals. Tadpoles may also be the dominant grazers in aquatic systems, helping keep streams from clogging up with algae. When frogs disappear, other animals follow, and ecosystems are forever altered.

Read more:
A deadly fungus threatens to wipe out 100 frog species – here’s how it can be stopped

When meeting your local frogs, be careful not to disturb them or their habitat, and clean your shoes if going to more than one area of frog habitat so you don’t accidentally spread frog disease. One of the best ways to learn about your local frogs, and to help understand and conserve them, is by recording their calls using the free FrogID app.

Here are some of the frog species you are likely to hear, and maybe even see, this summer.

1. Peron’s tree frog

Peron’s tree frog (Litoria peronii) is a large frog species that can be found in southern Queensland, New South Wales, Victoria and southeastern South Australia.

With cream to dark grey skin flecked with tiny emerald spots, cross-shaped pupils, and a loud, laugh-like call, this frog species is very commonly encountered around our homes — often hiding in pot plants, watering cans or even our letterboxes.

2. Motorbike frog

While the haunting call of the moaning frog (Heleioporus eyrei) fills autumn and winter nights around Perth, the motorbike frog (Litoria moorei) makes up a large part of Perth’s summer soundtrack.

Common in backyards throughout the southwest of Western Australia, this species is named after its drawn-out call, resembling an old motorbike racing up the street, changing gears.

This large tree frog, variably marbled with green and gold, often basks in the sun on reeds during the day.

3. Striped marsh frog

The striped marsh frog (Limnodynastes peronii) is commonly heard but rarely seen throughout its range along eastern Australia from north Queensland to Tasmania, and into the eastern edge of South Australia.

Its call is familiar to many, resembling a tennis ball being hit, or a dripping tap. This species loves backyard ponds, and is found even in the most built-up areas of cities, creating foamy nests for their eggs after a successful night of calling.

Adults have smooth, striped brown skin, and long, spidery toes. Males can be distinguished by females as they have much more robust arms.

4. Banjo frog

Banjo frogs occur throughout much of Australia, with a familiar loud “bonk” call, somewhat resembling the pluck of a banjo string reverberating from dams, wetlands and slow-flowing sections of streams and rivers.

During dry times, banjo frogs bury themselves underground, emerging after, or sometimes just before, summer rains. They are large, rather solid, frogs with a round snout, and are often mistaken for cane toads.

There are four species of banjo frog. In the southeast, the eastern banjo frog (Limnodynastes dumerilii) is very common, particularly in farm dams. Meanwhile, the northern banjo frog (Limnodynastes terraereginae) lives in northern NSW and throughout much of Queensland.

The giant banjo frog (Limnodynastes interioris) can be found in inland NSW and Victoria, and the western banjo frog (Limnodynastes dorsalis) is found in southwestern Western Australia.

5. Stonemason toadlet

The stonemason toadlet (Uperoleia lithomoda) is a tiny brownish-grey burrowing frog found across the top of Australia: in north Queensland, the Northern Territory and Western Australia.

This species emerges from underground after heavy monsoonal rains, and males produces an extraordinarily loud call that sounds like a harsh “click”.

With bumpy skin, they resemble toads enough to be called “toadlets”, and are often mistaken for young cane toads (Rhinella marina).

6. Eastern dwarf tree frog

The eastern dwarf tree frog (Litoria fallax) is highly adaptable and usually found along the east coast, from north Queensland to the borders of NSW and Victoria.

In recent years, it has also established populations in Victoria, well outside its native range, likely as a result of hitchhiking on produce or nursery plants.

Like the motorbike frog, the eastern dwarf tree frog is often seen during the day, basking in the sun, and will even call during the day on vegetation far from water.

The Conversation

Jodi Rowley, Curator, Amphibian & Reptile Conservation Biology, Australian Museum

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Australians recorded frog calls on their smartphones after the bushfires – and the results are remarkable

Jodi Rowley

Jodi Rowley, Australian Museum and Will Cornwell, UNSW

Frogs are one of the most threatened groups of animals on Earth. At least four of Australia’s 240 known frog species are extinct and 36 are nationally threatened. After last summer’s bushfires, we needed rapid information to determine which frogs required our help.

This was a challenging task. The fire zone ranged from southern Queensland through New South Wales and Victoria, to Kangaroo Island off South Australia. The area was too large for scientists alone to survey, especially with COVID-19 travel restrictions.

But all was not lost. Thousands of everyday citizens across the fire zone, armed with their mobile phones, began monitoring their local frogs through an app called FrogID.

In research published today, we reveal how 45 frog species, some rare and threatened, were recorded calling after the fires. This has allowed us to collate a snapshot of where frog species are surviving – at least for now.

A hand holds a mobile phone displaying the FrogID app.
The FrogID app means anyone can help monitor frog numbers.
Jodi Rowley

Good news for a change

In late 2019 and early 2020, more than 17 million hectares of forest burned in Australia. By size, it was the largest fire season in southeastern Australia since European occupation.

Scientists knew the damage to many plant and animal species was likely to be dramatic, particularly for species already in trouble. Many of Australia’s frog species are already vulnerable, due to pressures such as disease and habitat loss. There was a very real risk the fires had pushed many frog species closer to extinction. However, information on how frogs respond to fires has historically been limited.

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FrogID is a free app downloaded to smart phones. Led by the Australian Museum, the project allows anyone to record a frog call and upload it. The FrogID team then identifies the species by its call, to create a national frog database.

Since the app launched in November 2017, more than 13,000 citizen scientists have recorded the calls of about 220,000 frogs across Australia. Before last summer’s fires, app users had submitted 2,655 recordings of 66 frog species in what would later become fire zones. This gave us a remarkable understanding of the frogs present before the fires.

Burnt bushland
In some places, the fires burnt so intensely it was hard to imagine any wildlife survived.
Dean Lewins/AAP

Within four months of the fires, app users submitted 632 recordings. These confirmed the existence of 45 of the 66 frog species known to live in the fire zones. Hearteningly, all 33 summer-breeding frog species recorded before the fires were also detected afterwards. In other words, there were no obviously “missing” frog species.

The frog species recorded most frequently in burnt areas were common, broadly distributed species of low conservation concern. These include the common eastern froglet (Crinia signifera) and striped marsh frog (Limnodynastes peronii).

However, rare and threatened species were also recorded in fire-damaged areas. These included:

  • the vulnerable southern barred frog (Mixophyes balbus), which lives in patches of forest along the NSW east coast. The species was recorded ten times after the fires in northern NSW

  • the mountain frog (Philoria kundagungan), endangered in NSW and known only from the headwaters of streams in a few pockets of rainforest in far northern NSW and southern Queensland. It is rarely encountered but was recorded once after the fires

  • the endangered giant barred frog (Mixophyes iteratus), found in forest from southeast Queensland to central NSW. It was recorded twice after the fires.

There was no clear trend in the ecological group or lifestyle of species that were detected post-fire. Burrowing frogs, tree frogs and ground-dwelling frogs were all detected, as were stream, pond, and land-breeding species.

Frog hides in burnt leaf litter
In many places, frogs survived the inferno against the odds.
Jodi Rowley

A powerful tool

The FrogID records are good news. They show some species have survived in the short term, and male frogs are calling to attract female frogs to mate with.

But there is still much we don’t know about the fate of these frogs. For example, many frogs species in southeastern Australia don’t call in the cooler months, so we don’t yet have a clear picture of how these species have fared over winter.

The frogs’ longer-term prospects also remain uncertain. Fire damage varies dramatically from place to place, and the survival of a frog species in one burnt area does not guarantee its survival in another. We remain worried about species with small geographic ranges, especially rainforest species more sensitive to fire.

Read more:
A deadly fungus threatens to wipe out 100 frog species – here’s how it can be stopped

We urgently need more information on how last summer’s fires affected Australia’s frogs. This is particularly important given the more frequent and severe fires predicted under climate change, combined with all the other threats frogs face.

Traditional biodiversity surveys by professionals will be needed. This is especially true for frog species of high conservation concern at remote or inaccessible sites, for which the FrogID app has little or no data.

But continued data collection by citizen scientists, through projects such as FrogID, will remain powerful tools. They allow information to be gathered quickly and at scale. This raises the chances that species suffering most after a catastrophic event might get the help they need.The Conversation

Jodi Rowley, Curator, Amphibian & Reptile Conservation Biology, Australian Museum and Will Cornwell, Associate Professor in Ecology and Evolution, UNSW

This article is republished from The Conversation under a Creative Commons license. Read the original article.