Tag Archives: Karrie Rose

Help scientists identify why dead frogs are unexpectedly turning up across eastern Australia

Australian scientists are calling on citizen scientists to help them understand why frogs in eastern Australia are dying in what seems to be record numbers.

Here’s more from a July 28, 2021 essay by Jodi Rowley (curator, Amphibian & Reptile Conservation Biology, Australian Museum at the University of New South Wales [UNSW]), and Karrie Rose (Australian Registry of Wildlife Health – Taronga Conservation Society, University of Sydney) for The Conversation (can also be found as a July 28, 2021 news item on phys.org), Note: Links have been removed,

Over the past few weeks, we’ve received a flurry of emails from concerned people who’ve seen sick and dead frogs across eastern Victoria, New South Wales and Queensland.

One person wrote:

“About a month ago, I noticed the Green Tree Frogs living around our home showing signs of lethargy & ill health. I was devastated to find about 7 of them dead.”

In most circumstances, it’s rare to see a dead frog. Most frogs are secretive in nature and, when they die, they decompose rapidly. So the growing reports of dead and dying frogs from across eastern Australia over the last few months are surprising, to say the least.

While the first cold snap of each year can be accompanied by a few localised frog deaths, this outbreak has affected more animals over a greater range than previously encountered.

This is truly an unusual amphibian mass mortality event.

In this outbreak, frogs appear to be either darker or lighter than normal, slow, out in the daytime (they’re usually nocturnal), and are thin. Some frogs have red bellies, red feet, and excessive sloughed skin.

The iconic green tree frog (Litoria caeulea) seems hardest hit in this event, with the often apple-green and plump frogs turning brown and shrivelled.

This frog is widespread and generally rather common. [emphasis mine] In fact, it’s the ninth most commonly recorded frog in the national citizen science project, FrogID. But it has disappeared from parts of its former range. [emphasis mine]

We simply don’t know the true impacts of this event on Australia’s frog species, particularly those that are rare, cryptic or living in remote places. Well over 100 species of frog live within the geographic range of this outbreak. Dozens of these are considered threatened, including the booroolong Frog (Litoria booroolongensis) and the giant barred frog (Mixophyes iteratus).

Here’s more about the Australian agencies investigating the mass mortality event and some information about how you can help, from the July 28, 2021 essay by Rowley and Rose,

… the Australian Registry of Wildlife Health is working with the Australian Museum, government biosecurity and environment agencies as part of the investigation.

While we suspect a combination of the amphibian chytrid fungus and the chilly temperatures, we simply don’t know what factors may be contributing to the outbreak.

We also aren’t sure how widespread it is, what impact it will have on our frog populations, or how long it will last.

While the temperatures stay low, we suspect our frogs will continue to succumb. If we don’t investigate quickly, we will lose the opportunity to achieve a diagnosis and understand what has transpired.

We need your help to solve this mystery.

Please send any reports of sick or dead frogs (and if possible, photos) to us, via the national citizen science project FrogID, or email calls@frogid.net.au.

You can find FrogID here. At this writing (Monday, Aug. 2, 2021), there doesn’t seem to be a specific link to the current investigation on the FrogID homepage, which is devoted to reporting frog sounds. However, at the bottom of the homepage there is a ‘Contact us’ section with a ‘Research Enquiries’ option.

For any Canadians who are reading this and are unable to participate but would still like to contribute to frog welfare, there’s a Canadian effort, frogwatch. For anyone in the UK, there’s Froglife. Both of which, like FrogID, are citizen science projects.