Parents 'freak out' after unusual growths found spreading on backyard frogs

Cancers not previously seen in Aussie frogs have been documented. And it's got the families who love them worried.

A toddler sits on a deck looking out at a backyard is the background image. An inset shows a frog with cancer.
Australian parents have been "freaked out" after discovering the frogs their kids love in their backyards are sick. Source: Pergolotti/Frog Safe/Michael Dahlstrom

Parents have reported being “freaked out” after discovering the wild native frogs that their kids love to watch are sprouting globulous growths on their faces.

They’ve collected the infected animals from their backyards and sent them to Deborah Pergolotti who runs the Frog Safe non-profit group which helps rehabilitate the sick and injured. Her team maintains a database containing photographs of the affected animals, as well as information about where they were found, and what they were suffering from.

Strangely what the lab results are consistently showing is that the frogs are suffering from cancer — a disease that has historically been rare in amphibians.

“The public are very concerned about the frogs in their backyards, and almost feel possessive of them, and say: I want it back when it recovers,” Pergolotti told Yahoo News.

“But when you have a cancer case come in, and they call in and ask what was wrong with it, and you say it was cancer they freak out. They say: My kids were handling that frog. And they’re quite disturbed.”

Related: Rare mutant frog living in outback waterhole a 'once in a lifetime' discovery

A green tree frog with a cancerous bulge on its face.
A database contains recent cases of frog cancer found in Australia. Source: Pergolotti/Frog Safe Inc

What worries Pergolotti isn't that there's a risk to kids from frogs, but rather household and agricultural chemicals could be contributing to the development of cancers in frogs.

An Australian Museum and University of NSW study published in April found 36 per cent of frogs in eastern NSW had either a rodenticide or legacy pesticide in their livers.

While it's not known how these chemicals impact frog health in Australia, overseas research has linked pesticides to immune system suppression, malformations, changes in growth, development and reproduction.

Pergolotti would like to see more research funded to investigate whether there is a link, arguing that frogs have been “neglected” for a very long time.

“It’s difficult to find the political will on providing the funding so this can be properly researched,” she said.

“But they should know it’s very worrying for the public that the frogs are disappearing… and getting cancer.

“We very often will have someone turn in a frog, and they’ll say: Look, this is the second one I've seen with this lump on its face. When I saw the first one, I didn't know I should do anything. But then I found it dead a week later.”

A green frog in Australia with a white cancerous growth on its face.
People who find a frog with a suspected cancer are urged to contact Frog Safe for advice. Source: Pergolotti/Frog Safe Inc

The Frog Safe team, which relies on public donations, has been working with a local vet to investigate the problem. They’ve noticed numbers of frogs presenting with cancer slowly climbing, but Pergolotti suspects there are many more frogs suffering from cancer that simply aren’t being noticed.

Since 2020, Frog Safe has encountered four forms of the disease in northern Australia that they hadn’t encountered before.

The most recent was a neoplastic glaucoma found growing inside a frog’s eye. But they’ve also found spindle cell soft tissue sarcoma which resulted in the animal suffering from inflamed and missing skin.

The third type of cancer the team has assessed is subcutaneous, mesenchymal neoplasia, and the fourth is still under investigation.

If you spot a sick or injured frog, you can report it to the Frog Safe team here.

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