Dead, shrivelled frogs are unexpectedly turning up across eastern Australia. We need your help to find out why

Green Tree Frog
Jodi Rowley, Author provided

Jodi Rowley, Australian Museum and Karrie Rose, University of SydneyOver 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.

Another wrote:

We previously had a very healthy population of green tree frogs and a couple of months ago I noticed a frog that had turned brown. I then noticed more of them and have found numerous dead frogs around our property.

And another said she’d seen so many dead frogs on her daily runs she had to “seriously wonder how many more are there”.

So what’s going on? The short answer is: we don’t really know. How many frogs have died and why is a mystery, and we’re relying on people across Australia to help us solve it.

Why are frogs important?

Frogs are an integral part of healthy Australian ecosystems. While they are usually small and unseen, they’re an important thread in the food web, and a kind of environmental glue that keeps ecosystems functioning. Healthy frog populations are usually a good indication of a healthy environment.

The stony creek frog is one of the species hit by this mysterious outbreak.
Jodi Rowley, Author provided

They eat vast amounts of invertebrates, including pest species, and they’re a fundamental food source for a wide variety of other wildlife, including birds, mammals and reptiles. Tadpoles fill our creeks and dams, helping keep algae and mosquito larvae under control while they too become food for fish and other wildlife.

But many of Australia’s frog populations are imperilled from multiple, compounding threats, such as habitat loss and modification, climate change, invasive plants, animals and diseases.

Although we’re fortunate to have at least 242 native frog species in Australia, 35 are considered threatened with extinction. At least four are considered extinct: the southern and northern gastric-brooding frogs (Rheobatrachus silus and Rheobatrachus vitellinus), the sharp-snouted day frog (Taudactylus acutirostris) and the southern day frog (Taudactylus diurnus).

A truly unusual outbreak

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.

A browned, shrivelled green tree frog (Litoria caerulea)
Suzanne Mcgovern, Author provided

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. 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.

Other species reported as being among the sick and dying include Peron’s tree frog (Litoria peronii), the Stony Creek frog (Litoria lesueuri), and green stream frog (Litoria phyllochroa). These are all relatively common and widespread species, which is likely why they have been found in and around our gardens.

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).

The giant barred frog is a threatened species that lives in the geographic range of this outbreak.
Jodi Rowley, Author provided

So what might be going on?

Amphibians are susceptible to environmental toxins and a wide range of parasitic, bacterial, viral and fungal pathogens. Frogs globally have been battling it out with a pandemic of their own for decades — a potentially deadly fungus often called amphibian chytrid fungus.

This fungus attacks the skin, which frogs use to breathe, drink, and control electrolytes important for the heart to function. It’s also responsible for causing population declines in more than 500 amphibian species around the world, and 50 extinctions.

For example, in Australia the bright yellow and black southern corroboree frog (Pseudophryne corroboree) is just hanging on in the wild, thanks only to intensive management and captive breeding.

The teeny tiny southern corroborree frogs have been hit hard by the chytrid fungus.
Jodi Rowley, Author provided

Curiously, some other frog species appear more tolerant to the amphibian chytrid fungus than others. Many now common frogs seem able to live with the fungus, such as the near-ubiquitous Australian common eastern froglet (Crinia signifera).

But if frogs have had this fungus affecting them for decades, why are we seeing so many dead frogs now?

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

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Well, disease is the outcome of a battle between a pathogen (in this case a fungus), a host (in this case the frog) and the environment. The fungus doesn’t do well in warm, dry conditions. So during summer, frogs are more likely to have the upper hand.

In winter, the tables turn. As the frog’s immune system slows, the fungus may be able to take hold.

Of course, the amphibian chytrid fungus is just one possible culprit. Other less well-known diseases affect frogs.

The near-ubiquitous Austrlaian common eastern froglet is one species that seems able to live with the devastating chytrid fungus.
Jodi Rowley, Author provided

To date, the Australian Registry of Wildlife Health has confirmed the presence of the amphibian chytrid fungus in a very small number of sick frogs they’ve examined from the recent outbreak. However, other diseases — such as ranavirus, myxosporean parasites and trypanosome parasites — have also been responsible for native frog mass mortality events in Australia.

It’s also possible a novel or exotic pathogen could be behind this. So the Australian Registry of Wildlife Health is working with the Australian Museum, government biosecurity and environment agencies as part of the investigation.

Here’s how you can help

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.

Why green tree frogs are dying en masse is still a mystery.
Sophie Hendry, Author provided

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.

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

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Jodi Rowley, Curator, Amphibian & Reptile Conservation Biology, UNSW, Australian Museum and Karrie Rose, Australian Registry of Wildlife Health – Taronga Conservation Society Australia, University of Sydney

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

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Eastern China pinpointed as source of rogue ozone-depleting emissions

Sunset at Australia’s Cape Grim observatory, one of the key global background monitoring sites for CFC-11.
Paul Krummel/CSIRO, Author provided

Paul Krummel, CSIRO; Bronwyn Dunse, CSIRO; Nada Derek, CSIRO; Paul Fraser, CSIRO, and Paul Steele, CSIRO

A mysterious rebound in the emissions of ozone-depleting chemicals – despite a global ban stretching back almost a decade – has been traced to eastern China.

Research published by an international team today in Nature used a global network of monitoring stations to pinpoint the source of the rogue emissions. According to these data, 40-60% of the increase in emissions seen since 2013 is due to possibly illegal industrial activity in the Chinese provinces of Shandong and Hebei.

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After 30 years of the Montreal Protocol, the ozone layer is gradually healing

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Chlorofluorocarbon-11 (CFC-11) is a powerful ozone-depleting chemical that plays a major role in the appearance, each spring, of the ozone “hole” over Antarctica.

In the past, CFC-11 had been used primarily as a propellant in aerosol products and as a foam plastic blowing agent. The production and consumption (use) of CFC-11 are controlled by the global Montreal Protocol. CFC-11 consumption has been banned in developed countries since 1996, and worldwide since 2010.

This has resulted in a significant decline of CFC-11 in the atmosphere. Long-term CFC-11 measurements at Cape Grim, Tasmania, show the amount in the atmosphere peaked in 1994, and fell 14% by 2018.

However, this decline has not been as rapid as expected under the global zero production and consumption mandated by the Montreal Protocol since 2010.

Background levels of CFC-11 measured at Australia’s Cape Grim Baseline Air Pollution Station, located at the north-west tip of Tasmania.
CSIRO/Bureau of Meteorology

A 2014 study was the first to deduce that global emissions of CFC-11 stopped declining in 2002. In 2015, CSIRO scientists advised the Australian government, based on measurements compiled by the Advanced Global Atmospheric Gases Experiment (AGAGE), which includes those from Cape Grim, that emissions had risen significantly since 2011. The cause of this rebound in CFC-11 emissions was a mystery.

Global CFC-11 emissions based on atmospheric measurements compared with the expected decline of this compound in the atmosphere if compliance with the Montreal Protocol was adhered to.
CSIRO/AGAGE

An initial explanation came in 2018, when researchers led by Stephen Montzka of the US National Oceanic and Atmospheric Administration analysed the CFC-11 data collected weekly at Mauna Loa, Hawaii. They deduced that the increased emissions originated largely from East Asia – likely as a result of new, illegal production.

Montzka’s team concluded that if these increased CFC-11 emissions continued, the closure of the Antarctic ozone hole could be delayed, possibly for decades. This was a remarkable piece of detective work, considering that Mauna Loa is more than 8,000km from East Asia.

Suspicions confirmed

A still more detailed explanation is published today in the journal Nature by an international research team led by Matt Rigby of the University of Bristol, UK, and Sunyoung Park of Kyungpook National University, South Korea, together with colleagues from Japan, the United States, Australia and Switzerland. The new study uses data collected every two hours by the AGAGE global monitoring network, including data from Gosan, South Korea, and from an AGAGE-affiliated station at Hateruma, Japan. Crucially, Gosan and Hateruma are just 1,000km and 2,000km, respectively, from the suspected epicentre of CFC-11 emissions in East Asia.

The Korean and Japanese data show that these new emissions of CFC-11 do indeed come from eastern China – in particular the provinces of Shandong and Hebei – and that they have increased by around 7,000 tonnes per year since 2013.

Meanwhile, the rest of the AGAGE network has detected no evidence of increasing CFC-11 emissions elsewhere around the world, including in North America, Europe, Japan, Korea or Australia.

Yet while this new study has accounted for roughly half of the recent global emissions rise, it is possible that smaller increases have also taken place in other countries, or even in other parts of China, not covered by the AGAGE network. There are large swathes of the globe for which we have very little detailed information on CFC emissions.

Map showing the region where the increased CFC-11 emissions came from, based on atmospheric measurements and modelling.
University of Bristol/CSIRO

Nevertheless, this study represents an important milestone in atmospheric scientists’ ability to tell which regions are emitting ozone-depleting substances and in what quantities. It is now vital we find out which industries are responsible for these new emissions.

If the emissions are due to the manufacture and use of products such as foams, it is possible that, so far, we have seen in the atmosphere only a fraction of the total amount of CFC-11 that was produced illegally. The remainder could be locked up in buildings and chillers, and will ultimately be released to the atmosphere over the coming decades.

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Read more:
Explainer: what is the Antarctic ozone hole and how is it made?

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While our new study cannot determine which industry or industries are responsible, it does provide strong evidence that substantial new emissions of CFC-11 have occurred from China. Chinese authorities have identified, and closed down, some illegal production facilities over the past several years.

This study highlights the importance of undertaking long-term measurements of trace gases like CFC-11 to verify that international treaties and protocols are working. It also identifies shortcomings in the global networks for detecting regional emissions of ozone depleting substances. This should encourage expansion of these vital measurement networks which would lead to a capability of more rapid identification of future emission transgressions.

Paul Krummel, Research Group Leader, CSIRO; Bronwyn Dunse, Climate Science Centre, CSIRO Oceans and Atmosphere, CSIRO; Nada Derek, Centre for Australian Weather and Climate Research, CSIRO; Paul Fraser, Honorary Fellow, CSIRO, and Paul Steele, Centre for Australian Weather and Climate Research, CSIRO

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

The role of climate change in eastern Australia’s wild storms

Acacia Pepler, UNSW Australia

Australia’s east coast is recovering from a weekend of wild winds, waves and flooding, caused by a weather pattern known as an East Coast Low. Tragically, several people have died in flooding.

Parts of New South Wales have received more than 400mm of rain since Friday morning. Some places such as Canberra and Forster recorded their wettest June day on record. Waves have also caused severe coastal erosion and damaged property.

East Coast Lows are a type of low-pressure system or cyclone that occur on the Australian east coast. They are not uncommon, with about seven to eight lows a year causing widespread rainfall along the east coast, particularly during late autumn and winter. An East Coast Low in April last year caused similar damage.

But whenever they happen they raise the question: did climate change play a role?

Good news?

Climate models suggest that the cyclones that move through the global mid-latitudes, around 30° to 50°S, are moving south. This is contributing to long-term declines in winter rainfall in southwestern Australia and parts of southeast Australia.

These models also suggest that the atmospheric conditions that help East Coast Lows form could decline by between 25% and 40% by the end of the century.

In recent work, my colleagues and I looked even more closely at how climate change will affect individual East Coast Lows.

Our results also found East Coast Lows are expected to become less frequent during the cool months May-October, which is when they currently happen most often.

But there is no clear picture of what will happen during the warm season. Some models even suggest East Coast Lows may become more frequent in the warmer months.

And increases are most likely for lows right next to the east coast – just the ones that have the biggest impacts where people live.

This chart shows how the frequency of East Coast Lows could change by 2080 across May-October (left) and November-April (right). Red indicates fewer storms, while blue indicates more. Crosses show high agreement between climate models.

What about the big ones?

The results in the studies I talked about above are for all low-pressure systems near the coast – about 22 per year, on average.

But it’s the really severe ones that people want to know about, like the current event, or the storm that grounded tanker Pasha Bulker in Newcastle in June 2007.

These storms are much rarer, which makes it harder to figure out what will happen in the future. Most of the models we looked at had no significant change projected in the intensity of the most severe East Coast Low each year.

Warming oceans provide more moisture, so intense rainfall is expected to increase by about 7% for each degree of global warming. East Coast Lows are no different – even during the winter, when East Coast Lows are expected to become less frequent, the frequency of East Coast Lows with heavy rain is likely to increase.

Finally, even though there may be fewer East Coast Lows, they are occurring in an environment with higher sea levels. This means that many more properties are vulnerable to storm surges and the impact of a given storm surge is that much worse.

Was it climate change?

While the frequency of cool-season East Coast Lows looks likely to decrease in the future, changes in the big ones are a lot less certain.

However, East Coast Lows are very variable in frequency and hard to predict. So far, there hasn’t been any clear trend in the last 50 years, although East Coast Lows may have been more frequent in the past.

As for extreme rainfall, studies have found little influence of climate change on Australian extreme rainfall so far. Climate variability, such as El Niño, currently plays a much larger role. This doesn’t mean climate change is having no effect; it just means it’s hard to tell what impact a warming world is having at this stage.

So did climate change cause this weekend’s storms? No: these events, including intense ones, often occur at this time of year.

But it is harder to rule out climate change having any influence at all. For instance, what is the impact of higher sea levels on storm surges? And how much have record-warm sea temperatures contributed to rainfall and storm intensity?

We know that these factors will become more important as the climate system warms further – so as the clean-up begins, we should keep an eye on the future.

Acacia Pepler, PhD student, UNSW Australia

This article was originally published on The Conversation. Read the original article.

Road Trip Through Eastern Europe

USA: The Eastern Sierra

Australia: Koalas Now Recognized as a Threatened Species

Koalas in eastern Australia have now been listed as a threatened species. However, the Koala population is growing rapidly in both Victoria and South Australia.

For more, visit:
http://www.bbc.co.uk/news/world-asia-17893014

Australia: Wagga Wagga – Spiders Trying to Escape Massive Flooding

The link below is to an article reporting on the massive flooding currently impacting eastern Australia. This report is all about the spiders (Wolf and Orb) trying to escape the flood waters.

For more, visit:
http://io9.com/5891091/massive-spiderwebs-engulf-australian-town-as-arachnids-escape-floods

Shark Numbers Growing off Eastern Australia

Shark numbers appear to be growing off the east coast of Australia. In recent days large numbers of sharks, including Tiger Sharks have been spotted of the southeastern coast of Queensland at Teewah, feasting on large schools of baitfish and tuna.

For more information on sharks visit:

http://www.removesharknets.com/

http://www.sharksinternational.org/

AUSTRALIA: ENVIRONMENTAL DISASTER UNFOLDING ON QUEENSLAND COAST

An environmental disaster is unfolding on the Queensland coast, with the oil spill from the Hong Kong-flagged ship Pacific Adventurer. The Pacific Adventurer was badly damaged during the Cyclone Hamish weather event last week.

The Pacific Adventurer somehow managed to get caught up in the cyclone despite very early warnings concerning the cyclone. Some 31 containers containing ammonium nitrate were washed into the sea during the cyclone and as this occurred the ship itself was badly damaged, leaking some 230 tonnes of oil into the ocean. The initial report from the ship was that some 30 tonnes of oil had been lost.

The environmental disaster is huge, with the oil now affecting over 60km of coastline, including the eastern coast of Moreton Island. Sea life is being severely impacted by the disaster.

The cleanup is being done at a rate of about 1 to 2 km a day, which means it will take quite some time to complete.

Also of concern are the 31 containers of ammonium nitrate that are still missing and which could further contaminate the region. Navy mine hunters are being called in to search for the containers which remain a shipping hazard.

AUSTRALIA: THE NORTH MARINE REGION

Peter Garrett, Australia’s Minister for the Environment, Heritage and the Arts, today released a report on the biodiversity, ecosystems and social and economic uses of the oceans of northern Australia. The report entitled ‘The North Marine Bioregional Profile,’ brings together and explores the available knowledge of the Arafura and eastern Timor Seas, from the Northern Territory/Western Australia border to Torres Strait, including the Gulf of Carpentaria.

The report is expected to assist the government to better understand and protect our marine environment, conserve biodiversity and determine the priorities in our marine conservation efforts. It will also assist industry to better plan and manage their activities in the region.

A Marine Bioregional Plan for the region covered in the report is expected to be handed down in 2010. In total there will be five plans covering Australia’s marine regions.

View The North Marine Bioregional Profile at:
http://www.environment.gov.au/coasts/mbp/north/index.html