Frogs the world over are in hot water and they need your help

A multitude of fatal factors have combined forces to give amphibians the dubious honour of becoming the most threatened group of animals on Earth; the silent amphibian assassin chytrid fungus, pollution and habitat degradation, invasive species, and climate change are to blame.

South Australian Rupert Mathwin, Ecologist at Flinders University in Adelaide, told Cosmos that more than 41% of the world’s amphibian species are currently threatened with extinction.

“Sadly, this is predicted to worsen,” he said.

Now, more than ever, a thorough and accurate understanding of the numbers and distribution of local frog species is vital to their management. This means getting all hands (and ears) on deck to monitor them.

While collating all of SA’s frog calls into a single dataset – to study frogs in the Murray River – Mathwin discovered that citizen science data is essential for filling the gaps that exist around government monitoring programs.

Two men teaching three children how to use a mobile app next to a creek
Steve Walker (left) and Rupert Mathwin (right) teach children how to use the FrogSpotter citizen science mobile app to record frog call surveys in Bridgewater, South Australia. Credit: Jason Vanlaarhoven

“Government ecologists routinely monitor specific frog populations to measure the success of conservation activities, and the health of those populations. To assess change over time, ecologists revisit the same populations at the same times of year. This creates a detailed dataset for comparison, but it creates a very narrow focus,” he said.

“Citizen scientists, on the other hand, monitor across seasons and location, which contributes to a much richer picture of frog populations. As a result, they have recorded more than twice as many South Australian frog species as their government colleagues and 18,000 records are from areas with no routine monitoring programmes.

“The dataset also includes times of year and times of day that aren’t captured by routine monitoring. For example, citizen scientists have increased the number of records from January to April by more than 1000%!”

According to Mathwin, 87% of South Australia’s frog call records were collected by citizen scientists in programmes such as iNaturalist, FrogID, and FrogWatch SA.

“Without these programmes we would have no information from some regions.”

FrogWatch SA

The FrogWatch SA citizen science project supports individuals, schools, and local groups to gain a more comprehensive understanding of how South Australia’s 31 frog species are tracking over time.

“South Australia’s citizen scientists began monitoring in 1990 with the advent of a schools-based Frogwatch program, followed by the Environment Protection Authority’s Frog Census in 1994. These programs motivated more than 2,000 volunteers to record their local frog choruses on audio cassettes and send them for expert identification. Audio cassettes have since been replaced with smartphones, but the enthusiasm of participants is stronger than ever,” says Steve Walker, FrogWatch SA Coordinator and Green Adelaide Education Officer.

“The breadth of data collected by citizen scientists allows scientists to determine which environmental factors are important to our frogs, and how we can work together to safeguard their future.”

It’s easy to get involved: download the FrogSpotter app or register with the FrogWatch SA website, and head to a body of water during the early evening to record the frogs calling for three to five minutes.

But don’t fret if all remains quiet! Recording the absence of frogs is just as useful as their presence because it provides information on where frogs are not breeding due to unsuitable conditions at that time.

Each species of frog has its own unique call, and this makes it easier for a panel of experts to identify which ones are present during each survey. It also means that you too can become a frog call expert by using the FrogWatch SA interactive training program.

FrogWatch SA survey recorded on 2 December 2022, in a wetland in the Murray Valley. Experts have identified the presence of the calls of the following species: Peron’s tree frog (Litoria peronii), spotted marsh frog (Limnodynastes tasmaniensis), southern bell frog (Litoria raniformis), and long-thumbed frog (Limnodynastes fletcheri). Credit: submitted by AKriesl

In no time you could be detecting the loud, banjo-like ‘bonk’s’ of the pobblebonk (Limnodynastes dumerilii).

The calls of an eastern banjo frog (Limnodynastes dumerilii). Credit: FrogWatch SA
Photograph of an eastern banjo frog
Eastern banjo frog (Limnodynastes dumerilii). Credit: Steve Walker

Or discerning the long, rapidly pulsed, musical trill of the painted burrowing frog (Neobatrachus pictus).

The calls of the painted burrowing frog (Neobatrachus pictus). Credit: FrogWatch SA
Photograph of a painted burrowing frog
Painted burrowing frog (Neobatrachus pictus). Credit: Steve Walker

If you’re especially lucky you could even discover the harsh, short, and slowly repeated grating ‘cre-e-ek’ of the southern toadlet (Pseudophryne semimarmorata) – a species which has only been recorded at a handful of sites in South Australia over the past 25+ years.

Calls of the southern toadlet (Pseudophryne semimarmorata). Credit: FrogWatch SA
Phtograph of a southern toadlet
Southern toadlet (Pseudophryne semimarmorata). Credit: Steve Walker

Just over the border, in Victoria and New South Wales, researchers are attempting to save an endangered species of frog: the Littlejohn’s tree frog (Litoria littlejohni).

A short documentary film about the species, Saving Littlejohn, is showing at the SCINEMA International Science Film Festival – the largest science film festival in the Southern Hemisphere.

The film looks into the factors threatening this small frog, and what researchers are doing to prevent it from going extinct, including establishing a captive breeding colony, collecting and cryopreserving sperm cells for a biobank, and seeking the help of citizen scientists.

Find out more at the 2023 SCINEMA International Science Film Festival

Watch the 2023 SCINEMA International Science Film festival entry, Saving Littlejohn, by registering to view it for free on the SCINEMA website. 

SCINEMA runs from 1 August to 31 August.

Register for Scinema 2023

SCINEMA runs from August 1 to August 31 every year. Register now to be part of the festival and watch the films for free. REGISTER NOW.

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