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Beachgoers in Australia are on high alert following four shark incidents in New South Wales in 48 hours.

On Tuesday morning, a surfer was bitten by a shark at Point Plomer, on the state’s mid-north coast. He was taken to hospital with minor injuries to one of his legs.

This came after a man was bitten by a shark on Monday evening, while surfing at Manly, on Sydney’s northern beaches. He suffered major wounds to his leg and was rushed to Royal North Shore hospital in a critical condition.

Only a few hours earlier, a shark knocked an 11-year-old boy into the water at Dee Why – just north of Manly – and bit a chunk out of his surfboard. And on Sunday afternoon, a 12-year-old boy was bitten by what authorities believe was a bull shark while swimming at a popular beach in Sydney Harbour. He is still in a critical condition in hospital.

It can be tempting to blame these incidents on sharks alone. But there’s emerging evidence the pollutants, pesticides and parasites we send into the ocean from land could shape not just where and when sharks and people cross paths – but also shark behaviour.

Recognising this bigger picture helps shift the focus from blaming sharks to addressing human impacts, supporting smarter policies that protect both public safety and ocean health.

A deeper reality

When shark attacks occur, the pain is real and profound. People are injured, families are shattered, and lives are changed forever. No discussion about ecology should ever minimise the human cost. Fear and anger in these moments are entirely understandable.

Yet public debate often moves quickly from grief to blame, with sharks portrayed as the problem to be removed.

This framing offers a sense of control. But it can also obscure a deeper reality: we still know surprisingly little about the many pressures shaping shark health and behaviour.

What happens on land doesn’t stay on land. When heavy rain washes into the ocean, it doesn’t just carry pollutants and microorganisms with it. It also changes the water itself. Salinity shifts, visibility drops, oxygen levels change and temperatures can fluctuate.

Think about how unsettled you would feel if the air you breathe, the water you drink and the streets you walk suddenly changed overnight. Marine animals experience similar disruption.

Heavy rainfall and heightened risk

The four recent shark incidents in New South Wales followed an intense rainstorm that flushed runoff from land into the state’s coastal waters, reducing visibility and carrying pollution and waste into the sea.

A 2019 study found tiger and white sharks are more likely to attack after heavy rainfall.

This is partly because heavy rainfall flushes out more nutrients to sea, which leads to higher fish populations near the shore. In turn, this attracts sharks.

Heavy rainfall also creates a very turbid, silty environment. Runoff-driven changes in water quality can disrupt the sensory cues sharks rely on, potentially increasing stress and altering behaviour, while reduced visibility also limits people’s ability to assess risk.

Pollutants and parasites

On land, scientists have long recognised that environmental pollutants can interfere with how the nervous system works.

For example, exposure to certain pesticides is linked to neurological diseases in people, such as Parkinson’s disease, because these chemicals can disrupt nerve cell function, energy production and brain signalling pathways.

Emerging research shows similar processes occur in animals. For example, experiments in laboratory rats exposed to a common chemical used in pesticides displayed significant long-term deficits in mood, anxiety, depression and aggressive traits. While these findings don’t automatically translate to wildlife in the ocean, they help explain how chemicals can affect the brain.

There’s also growing evidence that pollutants and pharmaceutical contaminants can alter swimming behaviour, aggression, memory and stress responses in freshwater fish such as Nile tilapia and zebrafish.

Although we know far less about these effects in marine species, the pattern is clear: chemicals entering aquatic environments can influence animal behaviour.

Pollution isn’t the only thing moving from land into the ocean. Microorganisms do too. One of the most striking examples is Toxoplasma gondii, a microscopic parasite best known for infecting humans and domestic animals. On land, it’s shed by cat faeces, and its hardy eggs can survive for months in soil and water.

Research shows these parasite stages can be washed into rivers, estuaries and coastal waters, where they’re taken up by fish and other marine animals. Toxoplasma has been detected in species ranging from fish to dolphins and sea otters.

What makes this parasite particularly important is its ability to influence behaviour. In studies on land, toxoplasma infection has been shown to reduce fear responses, increase risk-taking and alter how the brain processes threats.

Emerging evidence suggests similar effects may occur in marine animals, with potential consequences for predator–prey interactions and ecosystem balance.

Toxoplasma has not yet been reported in sharks, largely because sharks are rarely examined for this parasite.

This gap reflects limited investigation, rather than clear evidence that sharks are unaffected. This doesn’t mean parasites cause shark incidents. But it does highlight how microorganisms originating on land can enter the ocean and influence animal health and behaviour in subtle ways we are only beginning to understand.

Long-term solutions lie upstream

One practical step to reduce the risk of shark attacks is clearer public guidance around swimming after major rain or similar events, when water quality and visibility change rapidly.

Temporary beach closures and consistent warnings following heavy rainfall are low-cost, evidence-based measures that reduce risk without targeting wildlife.

Longer-term solutions lie upstream – in policy and research.

Investment in stormwater management, wastewater infrastructure and runoff reduction helps stabilise coastal conditions and improve ocean health. It can also help reduce biological pressures by limiting parasite exposure.

There is also a clear need to invest in research in areas that remain poorly studied. Even major research efforts on iconic species such as great white sharks have tended to focus on movement and behaviour, while largely overlooking parasites and disease.

Shokoofeh Shamsi, Professor in Veterinary Parasitology, Charles Sturt University

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

Four people have now been bitten by sharks in the last two days in New South Wales, including three in Sydney Harbour. Two people are in critical condition.

The shark species responsible isn’t yet known. But some of these incidents likely involved the highly adaptable bull shark (Carcharhinus leucas). This unique fish species can tolerate a wide range of water salinity, from oceans to brackish estuaries, and even freshwater rivers.

Bull sharks have long been found in warmer Australian waters, ranging from south-west Western Australia, all the way around the Top End and down the east coast as far as the New South Wales-Victorian border.

The movements of bull sharks in Sydney Harbour have been studied for several years. Their presence is more likely when waters are warmer over summer. But they’re staying longer than before. Last year, researchers found that bull sharks were spending on average an extra day per year in their summer grounds (shallower coastal waters, estuaries and rivers) as ocean temperatures rise due to climate change.

Record heavy rains in Sydney flushed plenty of nutrient-rich water from farms and wastewater treatment plants into the river system, including the harbour. This nutrient runoff attracts more prey such as baitfish and larger fish, and in turn larger predators such as sharks. Stormwater also makes harbour waters murkier, which means that bull sharks rely more on hearing and electroreception than sight to locate food sources. This can lead to bites due to mistaken identity.

Although human activity (noise and movements) in the water can attract sharks, humans are not a food source for bull sharks. Almost all encounters and negative interactions from these sharks come from an exploratory bite. Unfortunately for those affected, the bites can be very serious.

What could be behind these incidents?

Bull sharks are unique among sharks in that they can tolerate fresh, brackish and salt water. Most other shark species don’t use estuaries or rivers as part of their home range or lifecycle. This ability to tolerate and adapt to different salinity levels is one reason bull sharks are found in both coastal waters and river systems around the world, including estuaries.

Once mature, female bull sharks will return to their home rivers to give birth to live young. Newborns are small adult replicas. As they grow, juvenile and sub-adult bull sharks travel down river systems and tend to live in the lower estuaries for the first five years of their life to avoid larger predators. During that time, they opportunistically feed on a range of prey to get bigger before moving into the open ocean.

Bull sharks are very opportunistic feeders. Scientists have found an astonishing variety of things in bull shark stomachs, such as wood, metal and other inorganic matter, though fish are their prey of choice.

Estuaries and harbours tend to have murkier water than the open ocean, as rivers often carry plenty of sediment and nutrients. This means bull sharks have to rely on senses other than sight, such as sound, which travels well underwater, smell, as well as their close-range ability to sense weak electrical fields caused by the movements of living creatures. Many shark bites are likely due to the habit bull sharks have of opportunistically biting in case it might be food.

Over the last week, pulses of stormwater have made Sydney Harbour murkier and more nutrient-rich, attracting baitfish and the predators who follow them.

Bull sharks, like other sharks, learn patterns quickly. Many species of shark have learned to associate the specific sound made by fishing boat engines with food. When fish are hooked or trapped in a net, sharks may be able to get a free feed. Dolphins do the same thing.

How can people stay safe?

Authorities have shut down at least 20 beaches in Sydney’s Northern Beaches for 48 hours.

This is a good move, as it will give the murkiness some time to clear. But it may take longer than this to fully clear.

As shark experts, we would recommend going further:

• avoid swimming in murky water wherever possible
• avoid swimming in Sydney Harbour after heavy rain
• avoid surfing at nearshore beaches until the dirty water clears
• avoid swimming where people are fishing, especially where fish cleaning occurs
• avoid swimming where baitfish are common, including where other marine predators such as dolphins are hunting
• monitor local council and state fisheries websites for updates on staying shark smart this summer.

It’s important not to overstate the risks. Almost all the negative interactions reported in the Australian database of shark incidents come from exploratory bites, or incidental bites of people fishing or even feeding sharks.

Queenslanders have had to adapt to the year-round presence of bull sharks in their rivers and coastal waters for many years. People don’t swim in bull shark hotspots such as the Gold Coast canals or the Brisbane River. Authorities recommend avoiding swimming and surfing up to a few days after heavy rain.

As the oceans warm, bull sharks are likely to spend more time in Sydney Harbour as well as other NSW estuaries. Sydneysiders and NSW residents may have to adapt to their extended presence. 

Vic Camilieri-Asch, Postdoctoral Research Fellow, Queensland University of Technology and Bonnie Holmes, Senior Lecturer in Animal Ecology, University of the Sunshine Coast

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

We all know trees are climate heroes. They pull carbon dioxide out of the air, release the oxygen we breathe, and help combat climate change.

Now, for the first time, our research has uncovered the hidden world of the tiny organisms living in the bark of trees. We discovered they are quietly helping to purify the air we breathe and remove greenhouse gases.

These microbes “eat”, or use, gases like methane and carbon monoxide for energy and survival. Most significantly, they also remove hydrogen, which has a role in super-charging climate change.

What we discovered has changed how we think about trees. Bark was long assumed to be largely biologically inert in relation to climate. But our findings show it hosts active microbial communities that influence key atmospheric gases. This means trees affect the climate in more ways than we previously realised.

Teeming with life

Over the past five years, collaborative research between Southern Cross and Monash universities studied the bark of eight common Australian tree species. These included forest trees such as wetland paperbarks and upland eucalypts. We found the trees in these contrasting ecosystems all shared one thing in common: their bark was teeming with microscopic life.

We estimate a single square metre of bark can hold up to 6 trillion microbial cells. That’s roughly the same number of stars in about 60 Milky Way galaxies, all squeezed onto the surface area of a small table.

To find out what these bark microbes were doing, we first used a technique called metagenomic sequencing. In simple terms, this method reads the DNA of every microorganism in a sample at once. If normal DNA sequencing is like reading one book, metagenomics is like scanning an entire library. We pulled out clues about who lived in the bark and which “tools” or enzymes they might have.

A simple analogy is to imagine a construction site where each tradespeople carries different tools. While some tools overlap, many are specific to their trade. If you see a pipe wrench, you can deduce a plumber is around.

In a similar way, metagenomics showed us the “tools” the microbes were carrying in their DNA – genes that let them eat atmospheric gases like methane, hydrogen or carbon monoxide. This gave us valuable insight into what the bark microbes could do.

But, like a construction site, having tools doesn’t mean the “tradies” are using them for jobs all the time. So we also measured the movement of gases in and out of the bark to see which microbial “jobs” were happening in real time.

Bark microbes eat gases

Many of the microbes living in bark can live off various gases. This is a process recently coined as “aerotrophy”, as in “air eaters”. Some of their favourite gases include methane, hydrogen and carbon monoxide, all of which affect the climate and the quality of the air we breath.

Methane is a potent greenhouse gas, responsible for about one third of human-induced warming. We found most wetland trees contained specialist bacteria called methanotrophs, that eat methane from within the tree.

We also saw abundant microbial enzymes that remove carbon monoxide, a toxic gas for both humans and animals. This suggests tree bark helps clean the air we breathe. This could be particularly useful in urban forests, as cities often have elevated levels of this harmful and odourless gas.

But one finding stood out above all others. Within every tree species examined, in every forest type, and at every stem height, bark microbes consistently removed hydrogen from the air. In other words, trees could be a major, previously unrecognised, global natural system for drawing down hydrogen out of the atmosphere.

Global possibilities

When we scaled up what these microbes were doing across all trees globally, the potential impact becomes striking. There are about 3 trillion trees on Earth, and together their bark has a huge cumulative surface area, rivalling that of the entire land surface of the planet.

Taking this into account, our calculation suggests that tree-microbes could remove as much as 55 million tonnes of hydrogen from the atmosphere each year.

Why does this matter? Hydrogen affects our atmosphere in ways that influence the lifetime of other greenhouse gases – especially methane. In fact, hydrogen emissions may be “supercharging” the warming impact of methane.

By using a simple model, the annual amount of hydrogen removed by bark microbes may indirectly offset up to 15% of annual methane emissions caused by humans.

In other words, if tree bark microbes weren’t doing this work, there would be more methane in the atmosphere, and our rising methane problem could be even bigger.

This also hints at another exciting possibility: planting trees could expand this microbial atmosphere-cleaning potential, giving microbes more surface area to apply their trade and help remove even more climate damaging gases from the air.

The ‘barkosphere’

Our research points to many exciting new possibilities and uncertainties around the previously hidden role of a tree’s “barkosphere”.

We want to know which tree species host the most active “gas-eating” microbes, which forests remove the most methane, carbon monoxide or hydrogen, and how climate change may alter these communities and their activities.

This knowledge could help guide future reforestation, conservation, carbon accounting strategies. It may even change the way we try and limit climate change.

Trees have always regulated our climate. But now we know their bark – and the hard working microscopic ecosystems living inside – may be far more important than previously thought. 

Luke Jeffrey, Postdoctoral Research Fellow, Southern Cross University; Chris Greening, Professor, Microbiology, Monash University; Damien Maher, Professor in Earth Sciences, Southern Cross University, and Pok Man Leung, Research Fellow in Microbiology, Monash University

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

Emma Johnston, the Vice-Chancellor of the University of Melbourne who has died aged 52, was a marine ecologist, a visionary leader in science and research, a passionate champion of the environment, a brilliant and engaging communicator, and a caring mentor. Emma was also our friend.

Born in 1973 and raised in Melbourne, Emma’s star rose swiftly. Her success was driven by a deep love of science, problem-solving and teamwork. Dux of University High School in Melbourne (where there is now a house named after her), she ran the student newspaper and launched an environment group and recycling program.

After completing a PhD in marine ecology at the University of Melbourne, Emma became an associate lecturer at UNSW in 2001, where she built a thriving research group studying the impacts of pollution and climate change on marine and coastal ecosystems. In 2005 she established the Sydney Harbour Research Program, to understand and remediate that city’s great natural asset.

These themes of complexity, interdependence and ecosystem resilience would become guiding metaphors for her subsequent career as a research leader and a fierce advocate for science.

Emma believed research should be about teamwork rather than personal accolades. She supervised a remarkable 33 PhD students, as well as honours students and postdoctoral researchers, and she mentored countless colleagues throughout her career. Busy but never hurried, Emma was generous with her time and attention, and she loved meeting bright and curious people.

As a newly promoted professor, she was chosen to attend the 64th Lindau meeting of Nobel Laureates where she delivered the after-dinner speech.

Her research and science communication earned awards including the NSW Premier’s Award for Biological Sciences, the Australian Academy of Science’s inaugural Nancy Millis Medal for Women in Science and the Eureka Prize for Promoting Understanding of Science Research.

In 2018, she was made an Officer of the Order of Australia for her services to higher education and scientific research. She became a fellow of the Australian Academy of Technological Sciences and Engineering in 2019 and of the Australian Academy of Science in 2022.

Emma’s leadership has taken many forms. As president of the student union while at university, she delighted in political jousting and loud change-making. Each time she was underestimated in a new role, she was fond of reminding friends that her term as student union president had prepared her for even the cagiest reception.

As a presenter on TV show Coast Australia, her natural style and genuine delight at the wonders of the wild ocean resonated with audiences worldwide.

In 2017, Emma became president of Science & Technology Australia. While there, she helped establish the acclaimed Superstars of STEM program, which works to raise the profile of women and non-binary scientists, and became the organisation’s first president to address the National Press Club, where she proclaimed science’s potential to provide solutions for humanity’s problems.

At around the same time, she was appointed Dean of Science at UNSW, albeit after some initial reluctance about how the job would impinge on her time with her two young children. When her prospective employer offered her more money for childcare, she replied that she actually wanted to see her children, and that a better solution would be simply to not expect her to go to functions most nights of the week.

In February 2025, after a stint as Deputy Vice-Chancellor (Research) at the University of Sydney, Emma returned to her alma mater as Vice-Chancellor of the University of Melbourne. This appointment positioned her better than ever to work towards her dream of a resilient, informed and motivated citizenry that can weather the storms of climate upheaval and build a strong future for humanity and the planet.

As a member of the board of CSIRO and a governor of the Ian Potter Foundation, Emma’s leadership and impact on Australian research was broad.

She had a formidable clarity of purpose, and an abiding hope for humanity. Her resilience strategy for the University of Melbourne, finalised just weeks before her death on December 26 2025, was the first step in her ten-year plan to build an extraordinary, empowered and resilient Australia.

As director of the board of the Great Barrier Reef Marine Park Authority, Emma led the 2021 State of the Environment report for the Australian government. In it, she emphasised that the ocean could only absorb so much heat before it would reach catastrophic collapse. Emma wanted nothing less than to save the world, but – like the ocean – in the end she could only do so much.

Emma’s final months were marked by a fierce doubling-down on her mission – she understood she was running out of time. Only 52 years old when she died from complications associated with cancer, she still wasn’t done with parenting, with saving the oceans and the planet, with nurturing and uplifting the next generation, or with remaking the Australian research and higher education landscape.

In a recent voice memo to one of us (Kylie), she said:

What has driven me in my life is a deep love of the science, a love of working with people and helping them to flourish and achieve, and a desire to work with others to protect this world I was immersed in as a scientist. And in that, I feel I have gone well beyond what I ever set out to achieve.

Survived by her husband Sam and their two children, Emma Johnston truly was a leader for our age, a star whose light burned out too soon.

Kylie Walker, Visiting Fellow, National Centre for the Public Awareness of Science, Australian National University and Rob Brooks, Scientia Professor of Evolution, UNSW Sydney

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

Today, rock wallabies are seen as secretive cliff-dwellers that rarely stray far from the safety of their rocky shelters. But the fossil record tells a very different story.

New research suggests rock wallabies were once travellers, moving across country in search of new habitat. These wandering wallabies, including one that travelled over 60 kilometres, were far more mobile than other kangaroos at the time, even their giant extinct cousin Protemnodon.

These findings reshape our understanding of how rock wallabies interact with their environment and how they may respond to the increasingly fragmented landscapes of modern Australia.

Homebodies by nature?

Modern rock wallabies spend their days sheltering in rocky caves, crevices, and boulder piles, emerging at dusk to feed. They have tiny home ranges, often less than 0.2 square kilometres.

Rock wallabies aren’t fussy eaters, eating leaves and shoots from grasses or shrubs that grow near their rocky refuges. This has led to the assumption that they don’t travel far, sticking together in small groups on isolated habitats. Why travel far when everything you need is right outside your shelter?

We saw the same pattern in their distant cousin, the giant forest wallaby, Protemnodon, which had small ranges despite their much larger bodies.

Male rock wallabies have been observed occasionally dispersing up to 8km between colonies. While such movements are rare, they may play a crucial role in maintaining gene flow between populations.

Rock wallabies occur in isolated regions across much of mainland Australia, from the Cape York rock wallaby at the northern tip of Australia, to the yellow-footed rock wallaby of the Flinders Ranges, South Australia, and west to the Rothschild’s rock wallaby in the Pilbara, Western Australia.

This broad distribution raises intriguing questions. Were rock wallabies once more mobile than they seem today? And if so, can we see evidence of that movement in the fossil record?

Mount Etna caves

North of Rockhampton, Mount Etna Caves National Park sits right in the heart of rock wallaby country. Rich fossil deposits provide a window into the past 500,000 years, revealing how kangaroos once lived.

From these deposits, we examined fossils from kangaroos of all sizes, ranging from tiny pademelons (Thylogale), through to the megafauna forest wallaby (Protemnodon), as large as an adult human. This let us compare how far different-sized kangaroos travelled. Did small species stay closest to home while the largest roamed?

How fossil teeth reveal childhood location

To answer these questions, we turned to clues hidden in teeth. When kangaroos eat, unique chemical signatures (strontium isotopes) become locked in their enamel.

Because enamel forms early in life and doesn’t change, the strontium preserved in an animal’s teeth can tell us where it grew up. At Mount Etna Caves, there is no evidence kangaroo remains were brought there by predators to eat. So, we can be confident the patterns we see in their teeth reflect real movements during the animal’s lifetime.

Our results showed that regardless of size, most kangaroos were locals. Rock wallabies showed strong site fidelity, foraging less than 1km from the caves where their fossilised remains were found.

This strong attachment to rocky shelter mirrors modern species observations. Even as the environment changed over hundreds of thousands of years, most rock wallabies maintained small home ranges.

The travellers

While most rock wallabies kept close to the caves, a few individuals found at Mount Etna Caves were born elsewhere. Some originated 8km north near Mount Yaamba, and others around 15km south near Mount Archer.

But our most surprising case was a very adventurous individual that travelled at least 65km, crossing mountains, floodplains, and even the Fitzroy River, which would have been prime crocodile country. This is the first direct evidence of long-range travel in an individual rock wallaby.

While movements over these kinds of distances haven’t been observed in rock wallabies today, genetic evidence from short-eared rock wallabies does show some connection between colonies separated by 67km.

This suggests that, although most rock wallabies stay local, a small number of travellers will leave their birthplace in search of new habitat. These rare long-distance dispersers would play an important role in keeping populations connected across the landscape. Because this kind of dispersal happens beyond the timeframes of human observation, without the fossil record we wouldn’t know this crucial part of rock wallaby natural history.

Modern implications

Importantly, our results also show fossil wallabies were dispersing from areas that are still home to rock wallabies today.

Unadorned rock wallabies still live around Mount Etna and Capricorn Caves, with another colony in the Mount Archer National Park. To the west of the Fitzroy River, Herbert’s rock wallaby occupies rocky outcrops, just outside the town of Westwood.

Isotopic evidence tells us that, in the past, these three groups were not isolated pockets but part of larger interconnected populations.

We don’t know whether rock wallabies are still trying to make these journeys. But with major roads and development now dividing the landscape, humans might inadvertently be creating barriers for these rare but crucial dispersal events.

Fossil and genetic evidence shows rock wallaby populations should not be viewed as isolated colonies, but as parts of a wider network that relies on long-distance dispersal to stay healthy. Recognising this is vital if we want these rock-loving, wandering wallabies to keep thriving in an increasingly urbanised environment.

Christopher Laurikainen Gaete, PhD Candidate, Wollongong Isotope Geochronology Laboratory, University of Wollongong; Anthony Dosseto, Professor of Biogeochemistry, University of Wollongong, and Scott Hocknull, Principal Research Fellow Applied Palaeontology & Palaeotourism, CQUniversity Australia

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

Around the world, wildlife and environmental crime is surging. It is estimated to be the fourth largest organised transnational crime sector, and to be growing at a rate two to three times faster than the global economy.

This kind of crime can take many forms, from the trafficking and trade of native species to the unlawful removal and clearance of habitat and species, lethal control such as poisoning of native animals, and illegal fishing.

There are several global assessments of these crimes and their impacts. But our understanding of their scope in Australia is limited.

This is a considerable problem, because Australia has unique and endemic wildlife species, high extinction rates, and is a country that is difficult to police due to its sheer size and vast remote areas. Our new, Australia-first study addresses this knowledge gap.

Published in Conservation Science and Practice, it reveals the most prevalent crimes against Australia’s wildlife and environment, and makes four key recommendations for urgent law reform.

Crimes in our backyard

Our unique Australian species, particularly reptiles, are prevalent in the international illegal pet market.

In one high-profile case from late 2024, a man was sentenced to three and a half years in prison for 19 offences of trafficking and export of native Australian wildlife.

He used 24 different post offices across Queensland, New South Wales, Victoria and the Australian Capital Territory to attempt to ship 99 reptiles out of the country in cruel and cramped conditions.

We don’t understand the full extent and impact of these crimes in Australia, but we do know they can be disastrous. Wildlife trafficking and illegal trade erodes biodiversity through the removal of native species from their habitats. It also fuels the spread of invasive species, parasites and diseases.

Illegal harvesting of fisheries and timber can drastically impact populations and ecosystems. Unlawful lethal control of animals can also devastate local populations.

For example, in 2018 a farmhand in rural Victoria was found guilty of illegally killing over 400 wedge-tailed eagles, a large and long-lived bird of prey which is protected by law.

In 2004, employees of a fish farm in Queensland were found to have shot and killed birds including egrets, night herons, pelicans, jabirus and ducks, in numbers one witness estimated to be “in the thousands” over a fourteen month period.

The first database of its kind

For our new study, we used publicly available prosecutions from the High Court of Australia, the Federal Court of Australia and the Supreme, District and County Courts in each state and territory to compile a database of wildlife and environmental crime at a national scale. This is the first database of its kind in Australia.

We identified a total of 120 prosecutions between 1995 and 2024. Most of the crimes were classified as unlawful removal or damage (36.7%), illegal harvest (32.5%), or trafficking and trade (17.5%).

The most commonly targeted groups were plant species (40.8%), fish (30.8%) and reptiles (11.7%). Common targets of illegal fishing were abalone and rock lobster.

Over half of the environmental crimes (61.3%) occurred in outer regional and remote areas of Australia. These crimes overlap with areas of both greater environmental concern as well as regions more difficult to police and enforce. An increase in the number of annual prosecutions was also observed over the study period.

Tackling these crimes

Four key measures could help address the causes and effects of wildlife and environmental crime:

1. Community education to promote understanding of the damage these crimes can cause, and the ways members of the community can identify and report offences.

2. Judicial training and support to help sentencing judges understand the damage caused by wildlife and environmental crime, and accept they are “real crimes” and not less serious than offences against people and private property. Sentences and sentencing remarks need to reflect the seriousness of these crimes to effectively deter and punish offenders.

3. Boosting resources and technology to investigate and prosecute. Governments need to invest in technology and staffing to properly detect and investigate wildlife and environmental crime. For example, satellite observation can be used to identify illegal vegetation clearance, while compliance officers are vital to the ongoing prevention and prosecution of illegal fishing offences. Continued efforts at our borders to crack down on wildlife trafficking and trade will also help preserve Australian species, particularly reptiles.

4. Harmonising national laws. We need offences, definitions and penalties relating to wildlife and environmental crime to be consistent across States and Territories, and the Commonwealth. We also need to ensure that investigators have powers that cross jurisdictional State and Territory borders.

These recommendations could help Australia lead in preventing wildlife and environmental crime. In turn, they would secure Australia’s unique biodiversity and habitats from crimes that are driven by financial greed and hugely harmful to our environmental, economic and social wellbeing.

Isabelle Onley, Postdoctoral Research Fellow, School of Biological Sciences, Adelaide University ; Katie Smith, Research Program Manger, Wildlife Crime Research Hub, Adelaide University ; Kellie Toole, Lecturer in Law, Adelaide University , and Phill Cassey, Director of the Wildlife Crime Research Hub, Australian Research Council Industry Laureate Fellow, Adelaide University

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

Victoria has just suffered some of its worst bushfires since the Black Summer fires of 2019–20. Over 400,000 hectares are estimated to have burnt so far, an area more than five times larger than Singapore.

Regional communities have been deeply affected. They need support to recover and rebuild their homes, towns and lives. And what about the state’s unique plants, animals and ecosystems?

Both large and small fires erupted in Victoria, and were extraordinarily widespread across diverse environments. They burned in the Wimmera–Mallee region in the northwest, the Otways in the southwest, central Victoria, northeastern Victoria and eastern Victoria, including the alpine region. This means a correspondingly diverse range of native plants and animals has been affected.

Compounding this, Victoria is the most cleared state in Australia. This makes it more difficult for animals to find suitable habitat outside of burnt areas in a fragmented landscape as they recover.

How will these fires affect nature?

Fires have short and long-term affects on wildlife. While a high proportion of animals can survive fires, the total numbers of insects, birds, frogs, reptiles, mammals and others that have died during the fires or afterwards, will still be large. This is due to severe burns, smoke, radiant heat or other injuries as they try to escape. Many animals get caught on fences as they move across landscapes seeking refuge.

We might think animals that can fly, such as many insects, birds and bats, should be able to easily escape. But smoke and extreme heat makes it difficult to breathe and regulate their body temperature, and can disorient wildlife. Temperatures soared well above 40°C during the fires. Along with intense winds, this took a heavy toll on some animals. Tragically, thousands of flying foxes died.

Many animals will have survived fires by finding refuge in protected waterways, caves, rock and boulder piles, or by going underground, including into wombat burrows. Echidnas dig into the ground and go to sleep, a clever tactic to conserve energy and reduce stress on the body.

After fires, animals face additional challenges. Feral cats and foxes are known to rapidly take advantage of burnt areas. Hunting and capturing their prey in more open habitat is easier. Potoroos, bandicoots, lizards and many others that survive initially may be hunted in the hours, days and weeks after a fire.

The long-term effects

The impact of fire can last for decades, or even longer. Many Australian wildlife species depend on logs and hollows in trees for shelter and to raise young. Fire can both create and destroy hollows.

Importantly, Victoria is the most cleared state in Australia. Hence, hollows are already short in supply and patchily distributed. For some tree species, they can take more than 100 years to form. Their loss puts pressure on threatened species including greater gliders, barking owls and spotted-tailed quolls.

Aquatic life is not immune to the effects of fire either. Rains that occur in burnt landscapes can wash ash, debris and toxins into waterways. This smothers underwater habitats and reduces oxygen and water quality for native fish, crayfish and amphibians. In some cases it leads to mass mortality, including fish kills.

How to respond?

Once bushfires are contained and it is safe to enter, government agencies, scientists and wildlife carers will get a clearer picture of fire severity and native wildlife that need help. They will undertake population surveys and develop a management plan. This may include culling invasive herbivores such as deer, laying poison baits to control feral cats and foxes and installing artificial refuges for native animals.

Agencies should take a whole-of-ecosystem view to ensure well intended actions don’t have unexpected consequences. While 1080 poison may be needed in some areas to help control non-native predators, it also poses a risk to dingoes, a threatened species in Victoria.

This includes the Wilkerr (dingo) population in the Big Desert-Wyperfeld region in northwest Victoria, estimated to number fewer than 100 adults. Approximately 60,000 hectares of Wilkerr habitat has burned. The fires may push Wilkerr into agricultural land seeking cover and water, increasing contact and conflict with livestock graziers. This situation needs to be thoughtfully managed to protect graziers, livestock and Wilkerr.

What should I do?

We can help in a range of ways. These include:

• putting out water dishes for animals with sticks or stones in them so small animals don’t drown
• donating to charities and organisations that take care of injured wildlife
• creating wildlife-friendly gardens that displaced animals may use.

Members of the public should not attempt to feed wildlife, and leave this to experts. Likewise, approaching injured animals is not advised, including kangaroos and snakes. Stressed animals can behave erratically and aggressively, and should only be taken care of by experienced wildlife experts.

Governments must change course

As a wildlife ecologist and conservation expert, these fires bring an unwelcome but familiar mixture of deep sadness and intense frustration. As the climate gets hotter, such events will only become more likely and more severe.

Governments must substantially increase efforts to curb climate change, including a rapid transition away from fossil fuels. Likewise, we need far stronger environmental laws, and greater government investment to protect and recover the wildlife and places Australians love.

Fire has shaped Australia’s environments, and many species are adapted to survive and even benefit from fire. But the increasing regularity of severe fires will push some wildlife and ecosystems into oblivion. As with people and communities, we have a duty to provide Australia’s native plants, animals and other life with a safe and secure future.

Euan Ritchie, Professor in Wildlife Ecology and Conservation, School of Life & Environmental Sciences, Deakin University

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

Late last year, the New South Wales government announced an additional A$9.5 million in funding to support honeybee keepers in the wake of the 2022 arrival and subsequent spread of the Varroa mite.

Varroa mites attack honeybee larvae, reducing and even destroying entire colonies. This impacts honey production and the crop pollination services provided by honeybees.

However, the honeybee is not native to Australia. It’s an introduced species that has routinely escaped hives and gone feral, negatively impacting our native animals and biodiversity in general.

The new funding follows $58.4 million already spent by the NSW government in relation to the Varroa mite. It’s part of an ongoing trend of millions being spent on this exotic bee and pollination services to exotic crops, while largely neglecting the native plant-pollinator interactions that existed prior to European colonisation.

While some government and non-government funding is starting to look into alternative pollinators, thousands of Australian bee species and other native pollinators don’t enjoy nearly the same support as European honeybees. Native biodiversity is on the brink – but there’s work we can do to stop this.

The pollination crisis down under

Australia’s native pollinators include about 2,000 species of bees and many thousands of species of other insect pollinators. These include beetles, flies, wasps, butterflies and moths, as well as many of our bird and mammal species.

The biggest problem all these native pollinators face stems from our ignorance. Since the 1990s, the global decline of pollinators due to human activities, climate change and diseases has been a serious concern, especially in Europe and North America.

In Australasia this pollination crisis has been largely neglected, making it seem as if we’d dodged the bullet. However, our research shows the negative factors affecting pollinators elsewhere are just as present here.

The honeybee is so good at invading and proliferating in Australian landscapes, we now have some of the highest reported densities of feral honeybees in the world.

It’s likely honeybees adversely impact native pollinators and pollinator networks, because they compete for shared floral resources. The evidence available to date is consistent with this.

For example, recent studies have shown that native bees, when exposed to high honeybee densities, have fewer offspring and produce more males than females, which can lead to population declines.

The super-generalist honeybee can also harm our native pollination networks by facilitating the pollination of noxious weeds. It’s also likely native plants are receiving less pollination because honeybees have caused a decline in native pollinators.

However, it’s difficult to collect such evidence. It requires careful, time-consuming research. This difficulty has been compounded by an almost complete lack of funding for research on the impact of honeybees on native bees, and on Australia’s biodiversity.

An opportunity for native pollinators

The recent arrival of the Varroa mite provides an excellent opportunity to find out how Australia’s native pollinator systems will change in the wake of projected feral honeybee declines.

Governments around the country should urgently fund research on native pollinators. There are likely several hundred unnamed and thus unknown native bees in Australia. We need studies that identify them so we can learn more and protect them. Just recently one of us, Kit Prendergast, described a new species of native bee that visits a critically endangered plant. This research was not funded by any government.

Most importantly, as the Varroa mite is likely to continue spreading, it will significantly thin out the numbers of feral honeybees. This might be temporary as new feral honeybees escape from hives and replace them.

Still, it provides an opportunity for before-and-after studies, to understand the impacts of introduced honeybees on our native flora, fauna and ecosystems.

We have a narrow window to find out if native pollinators can recover after a temporary drop in feral honey bee densities. The time to carry out such studies is now, before the Varroa mite becomes ubiquitous.

Time for a new strategy

Ultimately, honeybees are not at risk of extinction. Despite the global pollinator decline, honeybees haven’t disappeared anywhere in the world, even in countries with far fewer resources than Australia. Nor has any plant species gone extinct from a lack of honeybees.

In contrast, there is overseas evidence of plant population declines due to the presence of honeybees and lack of native pollinators. In Australia, honeybees are so dominant and visit such a huge range of native plant species, they likely have extensive negative impacts.

We and a consortium of scientists are, without any current funding, developing a unique and much-needed Native Bee and Pollinator Conservation Strategy for Australia.

It will provide a clear, scientific evidence-based approach to safeguarding Australia’s unique pollinators and plants, and will provide practical and policy guidance to address the native pollinator crisis in Australia.

At present, protected areas in Australia are not selected based on their conservation value to pollinating insects. Of the three native bee species that are listed with being threatened with extinction on the Environment Protection and Biodiversity Conservation (EPBC) Act, none has a recovery plan.

There’s also general agreement feral animals shouldn’t be allowed in national parks. However, there are currently many licenced beekeeping sites on public land, including national parks and nature reserves.

It’s time for Australia’s governments to step up and invest in Australia’s native pollinators and the plants that rely upon their services, rather than pouring millions into the honeybee – a feral invasive species that jeopardises native wildlife. We implore them to do so.

Graham H. Pyke, Honorary Professor in School of Natural Sciences, Macquarie University; Amy-Marie Gilpin, Lecturer in Invertebrate Ecology, Western Sydney University, and Kit Prendergast, Postdoctoral Researcher, Pollination Ecology, University of Southern Queensland; Curtin University

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

Millions of years of isolation have shaped Australia’s extraordinary mammal fauna into species unlike anywhere else in the world, from platypus to koalas and wombats.

Tragically, Australia is the world leader in mammal extinctions. About 40 species have gone extinct in the 238 years since European colonisation began, and nearly 80 species are now imperilled. It’s essential we understand what factors caused these extinctions and ongoing decline.

Over many years, scientists have gathered compelling evidence demonstrating predation by introduced cats and foxes has been a key driver. Australian mammals have had millennia living alongside other predators such as wedge-tailed eagles and dingoes. But foxes and cats are extraordinarily capable and ecologically flexible hunters, quite unlike anything Australia’s mammals had confronted before.

Recently, some researchers have questioned whether these introduced predators really are responsible. In our new research, we lay out the clear lines of evidence implicating foxes and cats. For instance, extinct species tend to be small-to-medium mammals, the preferred prey size for these predators. When mammals are returned to fenced, fox- and cat-free areas, their populations often flourish.

Controversy in conservation

Last year, researchers questioned whether there was enough evidence to say feral cats and foxes had contributed to Australian mammal extinctions – and, by implication, their role in the ongoing decline of other threatened mammal species.

Their research drew on three premises relating to extinct and surviving mammals. If cats and foxes caused these extinctions, they argued that these should follow:

1. The last recorded sighting of a now extinct mammal from an area must come after the arrival of one or both of these predator species

2. Lethal management programs aimed at reducing fox and cat numbers should result in an increase in native mammal numbers in an area

3. Where cats and foxes are abundant, there should be fewer native mammals.

After testing these three ideas, the authors conclude the hypothesis foxes and cats cause extinctions “has come to be accepted with little evidence.”

The research caused a major stir among the conservation community, as it took aim at longstanding accumulated knowledge and questioned whether the evidence base was strong enough to justify efforts to control feral cats and foxes.

As experts with many decades experience working to protect threatened Australian mammals and other wildlife, we had a duty to evaluate their evidence.

Claim and counterclaim is essential to test, shape and hone science, and to provide a robust foundation for conservation management. It may seem like an academic argument, but it has clear real-world implications.

The survival and recovery of much of Australia’s native mammal fauna depends on controlling cats and foxes. Many recent success stories in bringing native animals back from the brink are due to removing foxes and cats.

If this objective is abandoned because of arguments feral cats and foxes are simply innocent bystanders, we risk rapidly losing many of these imperilled species.

What did we do?

A provocative claim in last year’s research was that some Australian mammal species may have gone extinct before foxes and cats ever got to the area. If this was true, cats and foxes couldn’t be held responsible.

Cats came with the First Fleet in 1788, augmented with many subsequent introductions. By the 1890s, feral populations had spread across the entire continent. Foxes came later, first introduced to southeastern Australia in the 1830s. They, too, spread out across most of the continent over decades.

We re-ran analysis of the historic data and found the last record of a now-extinct native mammal in an area was always dated after the arrival of cats. The picture is less clear for foxes, though this is understandable given the earlier arrival of cats would already have caused losses.

Further, the actual date of extinction may occur long after the last documented record, especially in remote, sparsely populated areas of Australia.

First Nations peoples and Europeans have witnessed and recorded many cases where a native mammal species disappeared from an area soon after one or both non-native predators arrived.

Fate provides further evidence. Many mammals were wiped out from their entire mainland ranges but survived on islands that cats and foxes never colonised. For instance, all mainland populations of the greater stick-nest rat have disappeared. But the species survives because it also had an island population. By contrast, the lesser stick-nest rat had no island population. It is now extinct.

Does fox and cat control work?

The authors argue fox and cat control doesn’t result in increases of threatened mammals. But this conclusion may stem from misreading data from feral cat and fox control programs. Not all control programs work to reduce cat numbers over long periods or even at all.

Instead, we can get far clearer evidence from what happens in safe havens – islands or fenced areas where foxes and cats are completely excluded. Threatened mammal species almost always increase in these areas and almost always decline at comparable sites where foxes and cats are not excluded.

Eastern barred bandicoots now roam Victoria’s fox-free Phillip Island, while hare-wallaby numbers are rebounding on Western Australia’s Dirk Hartog Island following the eradication of feral cats.

The assumption that native mammals should typically be less abundant when and where cats and foxes are more common doesn’t always hold. After periods of good rainfall in inland Australia, populations of native mammals and feral predators all increase. During droughts, predator and prey numbers both fall.

Difficult truths

The original analysis and our new research have a broader context. Some have argued the impact of introduced species has been overstated, and that introduced species should be seen as a legitimate part of Australia’s ecosystems. Scientific evidence and conservation outcomes do not support this.

Australia supports about 8% of the world’s biodiversity as one of just 17 megadiverse nations. Protecting our unique species is not easy. But the task for conservationists and policymakers will be even harder if feral cats and foxes are given a free pass to keep killing.

Lethal control is, unfortunately, necessary to protect many species near the brink of no return. It has to be done as humanely as possible and justified publicly. Stepping back would mean more and more extinctions.

We would like to acknowledge our research coauthors.

John Woinarski, Professor of Conservation Biology, Charles Darwin University; Euan Ritchie, Professor in Wildlife Ecology and Conservation, School of Life & Environmental Sciences, Deakin University; Katherine Moseby, Professor of Conservation Biology, UNSW Sydney, and Sarah Legge, Professor of Wildlife Conservation, Australian National University

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

The millions of species humans share the world with are valuable in their own right. When one species is lost, it has a ripple effect throughout the ecosystems it existed within.

But there’s a hidden toll. Each loss takes something from humanity too. Extinction silences scientific insights, ends cultural traditions and snuffs out spiritual connections enriching human life.

For instance, when China’s baiji river dolphin vanished, local memory of it faded within a single generation. When New Zealand’s giant flightless moa were hunted to extinction, the words and body of knowledge associated with them began to fade.

In these ways, conservation is as much about safeguarding knowledge as it is about saving nature, as I suggest in my research.

We’re currently living through what scientists call the planet’s sixth mass extinction. Unlike earlier events triggered by natural catastrophes, today’s accelerating losses are overwhelmingly driven by human activities, from habitat destruction to introduced species to climate change. Current extinction rates are tens to hundreds of times higher than natural levels. The United Nations warns up to 1 million species may disappear this century, many within decades.

This extinction crisis isn’t just a loss to broader nature – it’s a loss for humans.

Lost to science

Extinction extinguishes the light of knowledge nowhere more clearly than in science.

Every species has a unique genetic code and ecological role. When it vanishes, the world loses an untapped reservoir of scientific knowledge – genetic blueprints, biochemical pathways, ecological relationships and even potential medical treatments.

The two species of gastric-brooding frog once lived in small patches of rainforest in Queensland. These extraordinary frogs could turn their stomachs into wombs, shutting down gastric acid production to safely brooding their young tadpoles internally. Both went extinct in the 1980s under pressure from human development and the introduced chytrid fungus. Their unique reproductive biology is gone forever. No other frog is known to do this.

Studying these biological marvels could have yielded insights into human conditions such as acid reflux and certain cancers. Ecologists Gerardo Ceballos and Paul Ehrlich called their extinctions a tragic loss for science, lamenting: “Now they are lost to us as experimental models”. Efforts at de-extinction have so far not succeeded.

Biodiversity holds immense potential for breakthroughs in medicine, agriculture, materials and even climate change. As species vanish, the library of life shrinks, and with it, the vault of future human discoveries.

Lost to culture

Nature is deeply woven through many human cultures. First Nations people living on traditional lands hold detailed knowledge of local species in language, story and ceremony. Many urban residents orient their lives around local birds, trees, rivers and parks.

When species decline or vanish, the songs, stories, experiences and everyday practices built around them can thin out or disappear.

Extinction erodes our sense of companionship with the natural world and diminishes the countless small interactions with other species which help root our lives in joy, wonder and reverence.

The bioacoustics researcher Christopher Clark has likened extinction to an orchestra gradually falling silent:

everywhere there is life, there is song. The planet is singing – everywhere. But what’s happening is we’re killing the voices […] It’s like [plucking] the instruments out of the orchestra … and then it’s gone

One haunting example of a vanished voice comes from Hawaii. In 2023, a small black-and-yellow songbird, the Kauaʻi ʻōʻō, was declared extinct. All that’s left is a last recording, where the last male sings for a female who will never come.

Disturbingly, birdsong is declining worldwide, diminishing the richness of our shared sensory world.

From an ecocentric perspective, each loss leaves the whole community of companion species poorer – humans included. Scientists call this the “extinction of experience”. As biologist David George Haskell writes, extinction is leaving the future:

an impoverished sensory world […] less vital, blander.

The loss of species is not only an ecological crisis but also a rupture in the communion of life – a deep injury to the bonds uniting beings.

Loss of spiritual knowledge

For many communities, nature is imbued with sacred meaning. Often, particular species or ecosystems hold deep spiritual significance.

Australia’s Great Barrier Reef is venerated by Indigenous custodians, whose traditions describe it as part of a sacred, living seascape. As the reef’s biodiversity declines under climate stress, these spiritual connections are eroding, diminishing the sources of wonder, reverence and existential orientation which help define human belonging in the world – across and beyond faith traditions.

Some ecotheological traditions regard nature as a book – a way to reveal divine truth alongside scripture. Nature holds deep significance for the varied communities and traditions viewing the land and its creatures as sentient, interconnected and sacred.

Extinction weakens nature’s capacity to embody transcendent meaning. The natural world dims and dulls, leaving us with fewer opportunities to experience awe, beauty and a sense of the sacred. In this sense, extinction is more than biological loss. It severs spiritual ties between human and other beings in ways transcending worldviews.

How do we grieve extinction?

Extinctions often evoke grief, which is a way of knowing through feeling. Grieving a lost species points to the scale of the loss across scientific, cultural and spiritual dimensions.

For Indigenous communities, this grief can be profound, born of deep environmental attachment. Scientists and conservationists witness cascading losses and bear the burden of foresight. Their grief may trigger anxiety, burnout and sorrow. But mourning the lost also makes the crisis tangible.

Grieving for extinct life isn’t pointless. It can compel us to look closely at what remains, to recognise the intrinsic value of a species and to resist reducing biodiversity to its instrumental uses. This kind of mourning carries the seeds of ecological responsibility, inviting us to protect life not just for our purposes but because of its irreplaceable role in the communion of life.

Johannes M. Luetz, Adjunct Professor, University of the Sunshine Coast; UNSW Sydney; Alphacrucis College

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

Life in the ocean runs on light. It fuels photosynthesis, shapes food webs and determines where many marine species can live.

Gradually, that light is fading. Since the early 2000s, more than one-fifth of the global ocean has darkened as sediment, nutrients and organic matter increasingly cloud coastal waters – raising concern about the future of reefs, kelp forests and seagrass meadows.

Alarming as this picture is, focusing only on gradual darkening may miss the most ecologically damaging part of the story.

Our newly published study introduces the phenomenon of “marine darkwaves”: sudden, intense episodes of underwater darkness that can last from days to months and push marine ecosystems into acute stress.

Darkness events are often triggered by storms, floods, sediment plumes or algal blooms. As with marine heatwaves, these short, intense episodes can be just as ecologically disruptive as slow, long-term trends.

Why light matters underwater

When light within the ocean drops suddenly, even for a few days, marine ecosystems can suffer. Prolonged darkness can slow growth, reduce energy reserves and in severe cases lead to dieback or mortality.

Fish, sharks and marine mammals can also change their behaviour when visibility drops, altering feeding and movement patterns.

Until now, scientists have examined ways to track long-term coastal darkening but have lacked a consistent way to identify, measure and compare extreme short-term light-loss events across regions and depths.

In other words, we have known this phenomenon exists – but we haven’t had a shared language to define and describe it. With marine darkwaves, we now have an event-based framework for extreme underwater darkness.

Darkwaves occur when underwater light falls below a depth-specific threshold for a minimum duration, relative to what is normally expected at that location. This allows scientists to identify when conditions shift from merely dim to unusually dark.

Importantly, this framework works across different depths, where light conditions naturally vary; across local to regional scales, from coastal reefs to entire coastlines; and across multiple data sources, including light sensors and satellite observations.

Its consistency enables meaningful comparison of events that were previously difficult to place into broader contexts.

What our research revealed

Our study used long-term datasets from both hemispheres in markedly different coastal regions.

In California, 16 years of underwater light measurements revealed repeated darkwave events, some lasting several weeks. In Aotearoa New Zealand, ten years of monitoring data from Auckland’s Hauraki Gulf showed rapid drops in underwater light during storms, at depths of seven and 20 metres.

Satellite data extending back 21 years revealed a broader pattern. Along New Zealand’s East Cape coast, up to 80 marine darkwaves have occurred since 2002, most linked to storms and river-driven sediment plumes.

Cyclone Gabrielle in 2023 provided a stark example. The storm delivered vast amounts of sediment to coastal waters, smothering many reefs and creating prolonged underwater darkness over large areas.

In some places, the seabed received almost no light for several weeks.

Long-term averages are important, but they can smooth over the very events that cause the greatest ecological damage.

Just as a single marine heatwave can devastate kelp forests and coral reefs, a single marine darkwave can sharply reduce photosynthesis and disrupt ecosystems already stressed by warming, acidification and nutrient pollution.

Climate change is likely to increase the frequency and intensity of these events. Heavier rainfall, stronger storms and intensified land use all increase sediment and organic matter flowing into coastal waters, reducing water clarity and light availability.

Our framework allows identification of discrete periods when light thresholds critical for ecosystem function are crossed.

A new tool – and cause for hope

The marine darkwave framework complements existing tools used to track marine heatwaves, deoxygenation and ocean acidification.

By focusing on extremes, it provides clearer insights into acute stress on coastal ecosystems. In New Zealand particularly, this information is increasingly important for iwi (tribes) and hapū (sub-tribes), coastal communities, conservation groups and environmental managers making decisions about land use, restoration and marine protection.

Related monitoring work is already underway in parts of New Zealand, where expanded sensor networks aid in linking land-based processes to changes in underwater light, and linking these to ecological changes on coastal reefs.

Ultimately, marine darkwaves remind us that the ocean doesn’t always change slowly. Sometimes, it changes abruptly and quietly if we don’t pay attention.

There is also reason for cautious optimism. Many marine darkwaves are driven by land–sea connections, so their frequency and intensity are not inevitable.

Reducing sediment runoff through nature-based solutions, such as restoring wetlands, stabilising riverbanks, improving harvest techniques of exotic forests, and replanting native forests in vulnerable catchments can directly increase water clarity and underwater light.

Understanding marine darkwaves is not only about detecting change, but also about identifying practical pathways to protect coastal ecosystems before further darkness descends.

The authors acknowledge the contribution of Rahera Ohia, Ngāti Pūkenga, Jean Thoral, Leigh Tait and Cassandre Villautreix.

François Thoral, Postdoctoral Research Fellow in Marine Ecology, University of Waikato; Christopher Battershill, Professor in Coastal Science, University of Waikato; David R Schiel, Distinguished Professor in Marine Science, University of Canterbury, and Shinae Montie, Postdoctoral Research Fellow, The University of Western Australia

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

When the United States recently escalated its confrontation with Venezuela – carrying out strikes in Caracas and capturing President Nicolás Maduro – the moves were framed as political intervention.

But the raid also reflected a deeper contest over oil and critical mineral supply chains.

For Washington, controlling energy and strategic materials is now inseparable from power projection. That same logic is increasingly being applied in our own backyard – the Pacific seabed – where new mining could target minerals vital for batteries, electronics, clean energy and the military industrial complex.

What is deep‑sea mining?

In the Pacific, most attention today is on nodules in the Clarion‑Clipperton Zone (CCZ), a vast area between Hawaii and Mexico. This zone is administered by the International Seabed Authority (ISA), an intergovernmental body responsible for safeguarding the deep sea.

Nodules, which appear like potato-sized rocks, are found scattered across seabed plains four to six kilometres beneath the surface. These nodules are rich in nickel, cobalt, copper and manganese – metals used in electric vehicle batteries, smartphones and wind turbines.

Mining them involves driving a robotic “vacuum” over the seabed, pumping nodules up a riser pipe to a ship, and shipping concentrates ashore for processing.

Nodules aren’t the only target. Companies also eye sulfide deposits at hydrothermal vents and cobalt‑rich crusts on underwater mountains.

Increasingly, seabed minerals have become geopolitically important – and for two key reasons.

First, the energy transition is driving up demand for nickel, cobalt and manganese, with agencies projecting at least a doubling over the next two decades. Second, supply chains are concentrated in a handful of countries, making democracies nervous about choke points.

Policymakers and firms therefore see seabed minerals as a hedge: a way to diversify sources of “critical minerals” for clean energy and military defence.

Where mining meets fishing

Spanning 1.7 million square miles in international waters, the CCZ is earmarked for mining by 17 contractors under ISA licences.

At the same time, climate-driven shifts are drawing key tuna species – bigeye, skipjack and yellowfin – into the CCZ. Models suggest biomass increases of 10% to 30% for these species under warming scenarios. The result? Tuna fisheries and mining operations are set to share the same patch of ocean.

Mining plumes – clouds of sediment and metals stirred up at the seabed and discharged at the surface – could spread tens to hundreds of kilometres horizontally and hundreds of metres vertically.

For tuna and their plankton prey, the risks include stress on gills, disrupted feeding cues, and exposure to contaminants. Mid-water food webs could be hit hard: studies suggest over half of zooplankton and micronekton could be affected, rippling up to tuna stocks.

For Pacific economies reliant on tuna, this overlap represents a looming collision of industries. These tensions are already playing out in parts of the Pacific, including on New Zealand’s doorstep.

In 2025, the Cook Islands – a self-governing nation in free association with New Zealand – signed strategic agreements with both China and the United States: the former through a “Blue Partnership” for seabed mineral research and grants, and the latter via a joint commitment to science-led, responsible development.

This underscores how great-power competition is now converging on Pacific seabed resources.

In the same year, the US Department of the Interior began exploring deep-sea mineral leasing in federal waters near American Samoa. Local leaders flagged risks to tuna fisheries and culture, urging extended consultations.

The process remains exploratory, but it shows how seabed plans can collide with livelihoods even before a single robot touches the seafloor.

There are still plenty of unknowns about the environmental impacts.But we know mining removes life-bearing sediment and nodules and that sediment plumes can travel kilometres beyond the site. Decades-old disturbance tracks still show reduced biodiversity.

A 2024 study warned that plumes could mobilise metals into mid-water habitats, threatening marine life we barely understand. Recovery could take centuries – if it happens at all.

Why Pacific-led governance matters

The ISA has approved exploration but not exploitation; negotiations keep stalling amid calls, led by Pacific nations, for a moratorium or precautionary pause until science catches up.

Meanwhile, Pacific states are ratifying the High Seas Treaty, which will enable marine protected areas and require environmental impact assessments – tools to safeguard biodiversity and equity.

Sovereignty here isn’t abstract. In the Cook Islands, it means deciding if and when mining happens after community debate and science. In American Samoa, it means ensuring federal processes don’t undermine tuna-based livelihoods.

In a regional sense, it means Pacific voices shaping global decisions, rather than having rules imposed from afar.

Ultimately, the stakes are simple: risk a barely understood ecosystem to supply battery metals and military defence applications, or build the transition around circular materials, stronger land-based standards and robust ocean protections.

Pacific-led governance – grounded in science, culture and consent – is the best chance the world has to make sure decisions about the deep sea benefit people and nature, not just the next commodity cycle.

Viliame Kasanawaqa, Doctoral Researcher, Macmillan Brown Centre for Pacific Studies, University of Canterbury

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

It’s 7:45am. You grab a takeaway coffee from your local cafe, wrap your hands around the warm cup, take a sip, and head to the office.

To most of us, that cup feels harmless – just a convenient tool for caffeine delivery. However, if that cup is made of plastic, or has a thin plastic lining, there is a high chance it’s shedding thousands of tiny plastic fragments directly into your drink.

In Australia alone, we use a staggering 1.45 billion single-use hot beverage cups every year, along with roughly 890 million plastic lids. Globally, that number swells to an estimated 500 billion cups annually.

In new research I coauthored, published in Journal of Hazardous Materials: Plastics, we looked at how these cups behave when they get hot.

The message is clear: heat is a primary driver of microplastic release, and the material of your cup matters more than you might think.

What are microplastics?

Microplastics are fragments of plastic ranging from about 1 micrometre to 5 millimetres in size – roughly from a speck of dust to the size of a sesame seed.

They can be created when larger plastic items break down, or they can be released directly from products during normal use. These particles end up in our environment, our food, and eventually, our bodies.

Currently, we don’t have conclusive evidence on just how much of that microplastic remains in our bodies. Studies on this subject are highly prone to contamination and it’s really difficult to accurately measure the levels of such tiny particles in human tissue.

Furthermore, scientists are still piecing together what microplastics might mean for human health in the long term. More research is urgently needed, but in the meantime, it’s good to be aware of potential microplastic sources in our daily lives.

Temperature matters

My colleagues and I first conducted a meta-analysis – a statistical synthesis of existing research – analysing data from 30 peer-reviewed studies.

We looked at how common plastics such as polyethylene and polypropylene behave under different conditions. One factor stood out above all others: temperature.

As the temperature of the liquid inside a container increases, the release of microplastics generally increases too. In the studies we reviewed, reported releases ranged from a few hundred particles to more than 8 million particles per litre, depending on the material and study design.

Interestingly, “soaking time” – how long the drink sits in the cup – was not a consistent driver. This suggests that leaving our drink in a plastic cup for a long time isn’t as important as the initial temperature of the liquid when it first hits the plastic.

Testing 400 coffee cups

To see how this works in the real world, we collected 400 coffee cups of two major types around Brisbane: plastic cups made of polyethylene and plastic-lined paper cups which look like paper but have a thin plastic coating inside.

We tested them at 5°C (iced coffee temperature) and 60°C (hot coffee temperature). While both types released microplastics, the results revealed two major trends.

First, material matters. The paper cups with plastic linings released fewer microplastics than the all-plastic cups at both temperatures.

Second, heat triggers a significant release. For the all-plastic cups, switching from cold to hot water increased the microplastic release by about 33%. If someone drinks 300 millilitres of coffee in a cup made of polyethylene per day, they could ingest 363,000 pieces of microplastic particles every year.

But why exactly does heat matter so much?

Using high-resolution imaging, we examined the inner walls of these cups and found that all-plastic cups had much rougher surfaces – full of “peaks and valleys” – compared to the plastic-lined paper cups.

This rougher texture makes it easier for particles to break away. Heat accelerates this process by softening the plastic and causing it to expand and contract, creating more surface irregularities that eventually fragment into our drink.

Managing risks

We don’t have to give up our morning takeaway habit, but we can change how we approach it to manage the risk.

For hot drinks, the best option is to use a reusable cup made of stainless steel, ceramic, or glass, as these materials do not shed microplastics. If we must use a disposable cup, our research suggests that plastic-lined paper cups generally shed fewer particles than pure plastic cups, though neither is microplastic free.

Finally, since heat is the factor that triggers plastic release, avoid putting boiling liquids directly into plastic-lined containers. Telling the barista to make our coffee slightly cooler before it hits the cup can reduce the physical stress on the plastic lining and lower the overall exposure.

By understanding how heat and material choice interact, we can design better products and make better choices for our daily caffeine fix.

The author acknowledges the contribution of Professor Chengrong Chen to this article.

Xiangyu Liu, Research Fellow, School of Environment and Science and Australian Rivers Institute, Griffith University

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

Climate change is already fueling dangerous heat waves, raising sea levels and transforming the oceans. Even if countries meet their pledges to reduce the greenhouse gas emissions that are driving climate change, global warming will exceed what many ecosystems can safely handle.

That reality has motivated scientists, governments and a growing number of startups to explore ways to remove carbon dioxide from the atmosphere or at least temporarily counter its effects.

But these climate interventions come with risks – especially for the ocean, the world’s largest carbon sink, where carbon is absorbed and stored, and the foundation of global food security.

Our team of researchers has spent decades studying the oceans and climate. In a new study, we analyzed how different types of climate interventions could affect marine ecosystems, for good or bad, and where more research is needed to understand the risks before anyone tries them on a large scale. We found that some strategies carry fewer risks than others, though none is free of consequences.

What climate interventions look like

Climate interventions fall into two broad categories that work very differently.

One is carbon dioxide removal, or CDR. It tackles the root cause of climate change by taking carbon dioxide out of the atmosphere.

The ocean already absorbs nearly one-third of human-caused carbon emissions annually and has an enormous capacity to hold more carbon. Marine carbon dioxide removal techniques aim to increase that natural uptake by altering the ocean’s biology or chemistry.

Biological carbon removal methods capture carbon through photosynthesis in plants or algae. Some methods, such as iron fertilization and seaweed cultivation, boost the growth of marine algae by giving them more nutrients. A fraction of the carbon they capture during growth can be stored in the ocean for hundreds of years, but much of it leaks back to the atmosphere once biomass decomposes.

Other methods involve growing plants on land and sinking them in deep, low-oxygen waters where decomposition is slower, delaying the release of the carbon they contain. This is known as anoxic storage of terrestrial biomass.

Another type of carbon dioxide removal doesn’t need biology to capture carbon. Ocean alkalinity enhancement chemically converts carbon dioxide in seawater into other forms of carbon, allowing the ocean to absorb more from the atmosphere. This works by adding large amounts of alkaline material, such as pulverized carbonate or silicate rocks like limestone or basalt, or electrochemically manufactured compounds like sodium hydroxide.

Solar radiation modification is another category entirely. It works like a sunshade – it doesn’t remove carbon dioxide, but it can reduce dangerous effects such as heat waves and coral bleaching by injecting tiny particles into the atmosphere that brighten clouds or directly reflect sunlight back to space, replicating the cooling seen after major volcanic eruptions. The appeal of solar radiation modification is speed: It could cool the planet within years, but it would only temporarily mask the effects of still-rising carbon dioxide concentrations.

These methods can also affect ocean life

We reviewed eight intervention types and assessed how each could affect marine ecosystems. We found that all of them had distinct potential benefits and risks.

One risk of pulling more carbon dioxide into the ocean is ocean acidification. When carbon dioxide dissolves in seawater, it forms acid. This process is already weakening the shells of oysters and harming corals and plankton that are crucial to the ocean food chain.

Adding alkaline materials, such as pulverized carbonate or silicate rocks, could counteract the acidity of the additional carbon dioxide by converting it into less harmful forms of carbon.

Biological methods, by contrast, capture carbon in living biomass, such as plants and algae, but release it again as carbon dioxide when the biomass breaks down – meaning their effect on acidification depends on where the biomass grows and where it later decomposes.

Another concern with biological methods involves nutrients. All plants and algae need nutrients to grow, but the ocean is highly interconnected. Fertilizing the surface in one area may boost plant and algae productivity, but at the same time suffocate the waters beneath it or disrupt fisheries thousands of miles away by depleting nutrients that ocean currents would otherwise transport to productive fishing areas.

Ocean alkalinity enhancement doesn’t require adding nutrients, but some mineral forms of alkalinity, like basalts, introduce nutrients such as iron and silicate that can impact growth.

Solar radiation modification adds no nutrients but could shift circulation patterns that move nutrients around.

Shifts in acidification and nutrients will benefit some phytoplankton and disadvantage others. The resulting changes in the mix of phytoplankton matter: If different predators prefer different phytoplankton, the follow-on effects could travel all the way up the food chain, eventually impacting the fisheries millions of people rely on.

The least risky options for the ocean

Of all the methods we reviewed, we found that electrochemical ocean alkalinity enhancement had the lowest direct risk to the ocean, but it isn’t risk-free. Electrochemical methods use an electric current to separate salt water into an alkaline stream and an acidic stream. This generates a chemically simple form of alkalinity with limited effects on biology, but it also requires neutralizing or disposing of the acid safely.

Other relatively low-risk options include adding carbonate minerals to seawater, which would increase alkalinity with relatively few contaminants, and sinking land plants in deep, low-oxygen environments for long-term carbon storage.

Still, these approaches carry uncertainties and need further study.

Scientists typically use computer models to explore methods like these before testing them on a wide scale in the ocean, but the models are only as reliable as the data that grounds them. And many biological processes are still not well enough understood to be included in models.

For example, models don’t capture the effects of some trace metal contaminants in certain alkaline materials or how ecosystems may reorganize around new seaweed farm habitats. To accurately include effects like these in models, scientists first must study them in laboratories and sometimes small-scale field experiments.

A cautious, evidence-based path forward

Some scientists have argued that the risks of climate intervention are too great to even consider and all related research should stop because it is a dangerous distraction from the need to reduce greenhouse gas emissions.

We disagree.

Commercialization is already underway. Marine carbon dioxide removal startups backed by investors are already selling carbon credits to companies such as Stripe and British Airways. Meanwhile, global emissions continue to rise, and many countries, including the U.S., are backing away from their emissions reduction pledges.

As the harms caused by climate change worsen, pressure may build for governments to deploy climate interventions quickly and without a clear understanding of risks. Scientists have an opportunity to study these ideas carefully now, before the planet reaches climate instabilities that could push society to embrace untested interventions. That window won’t stay open forever.

Given the stakes, we believe the world needs transparent research that can rule out harmful options, verify promising ones and stop if the impacts prove unacceptable. It is possible that no climate intervention will ever be safe enough to implement on a large scale. But we believe that decision should be guided by evidence – not market pressure, fear or ideology.

Kelsey Roberts, Post-Doctoral Scholar in Marine Ecology, Cornell University; UMass Dartmouth; Daniele Visioni, Assistant Professor of Earth and Atmospheric Sciences, Cornell University; Morgan Raven, Associate Professor of Marine Sciences, University of California, Santa Barbara, and Tyler Rohr, ARC DECRA Fellow/Senior Lecturer, IMAS, University of Tasmania

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

Marine mammals are sentinels of the sea. When dolphins and whales show signs of stress or illness, it often signals deeper problems in the ocean ecosystems we all depend on.

But assessing the health of dolphins and whales is notoriously difficult. That’s because they spend most of their lives underwater, move over vast areas, and cannot be examined closely without causing stress or disturbance.

Our new research provides a promising solution to this problem. Published in the Journal of Thermal Biology, it shows how drone-mounted thermal cameras can help monitor dolphins’ vital signs such as skin temperature and breathing patterns.

Monitoring animals without handling them

Scientists have typically relied on hands-on methods to assess the health of wild marine mammals. These include attaching tagging devices or taking measurements during capture and handling.

While these methods can be effective, they are also invasive, expensive, logistically complex, and can alter the animals’ behaviour and physiology. This can induce stress, making results harder to interpret.

To fix this problem, researchers need tools that allow them to monitor dolphins repeatedly and accurately, while minimising disturbance.

One example is drones fitted with thermal cameras.

Thermal cameras detect heat emitted from surfaces, allowing temperature patterns to be measured remotely. When mounted on drones, they can potentially record this information from above, while animals continue to move freely.

In the case of dolphins, they have the potential to measure skin temperature and breathing patterns based on the heat emitted from the animals’ blowholes, body and dorsal fin, without having to get close or touch them.

But until now, no studies have tested how accurate, reliable or practical this approach is in real-world conditions.

Testing drones on dolphins

In our study, we used a drone-mounted thermal camera to measure dolphins’ body surface temperature and breathing rate under controlled conditions designed to reflect how dolphins are monitored in the wild.

The study involved 14 adult common bottlenose dolphins under human care at Dolphin Beach, Sea World on the Gold Coast, Australia. Testing was conducted across different heights, camera angles and environmental conditions to validate drone-based measurements.

We compared measurements obtained from drones with close-range reference data collected at the same time. Body surface temperature was measured using hand-held thermal cameras and breathing rates were calculated from the drone’s visual footage. This allowed us to assess how accurate and reliable the drone measurements were.

This approach required no restraint or tagging. Drone-based measurements were collected without physical handling of the animals.

We found that how the drone was flown substantially affected the accuracy of measurements. For example, flight height influenced how reliably body surface temperature and breathing rate could be estimated.

Measurements collected at lower altitudes, particularly about ten metres directly above the dolphin, consistently produced the most accurate results. At this height, body surface temperatures derived from thermal imagery closely matched close-range reference measurements taken at the same time.

As flight height increased, measurement accuracy declined. However, temperature estimates remained within approximately 1°C of the reference measurements.

Camera angle also influenced the accuracy of measurements. Thermal measurements were most accurate when the camera was positioned directly above the dolphin.

We could estimate breathing rates accurately from thermal imagery. Each breath produced a brief, localised increase in temperature at the blowhole that was clearly visible in the thermal footage.

Growing the conservation toolbox

These results show that drone-mounted thermal cameras can reliably measure dolphins’ surface temperature and breathing rate.

This represents a practical advance in how dolphin vital signs can be monitored in the wild. Until now, repeated measurements of temperature and breathing have typically required researchers to be close enough to dolphins to take measurements directly, such as from boats or by capturing and physically handling an animal.

This has limited how often measurements can be taken. Thermal drones offer a way to gather this information routinely, without significantly disturbing dolphins.

This approach has the potential to improve our ability to detect physiological changes and examine how dolphin health may vary over time in the wild. Combined with behavioural observations, drone-based thermal imaging could help explore links between surface temperatures, breathing patterns and environmental conditions.

Our study focused on dolphins under human care. But the same approach could be applied to free-ranging dolphins and other marine mammals for which close-range monitoring of vital signs is difficult.

As coastal ecosystems face growing pressure, tools such as thermal drones that allow researchers to monitor wildlife efficiently, repeatedly and non-invasively will become increasingly important. They provide a practical addition to the conservation toolbox, helping us better understand, and ultimately protect, dolphins and other animals in a changing ocean.

The authors would like to acknowledge the contribution of Dr. Andrew Colefax to this research and the Sea World, Gold Coast team for their support and in-kind contributions.

Charlie White, PhD Candidate, Behaviour and Evolution Lab, College of Science and Engineering, Flinders University and Guido J. Parra, Associate Professor, Research Leader of the Cetacean Ecology, Behaviour and Evolution Lab, Flinders University

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

In virtually every piece of land on Earth – from near the summit of Mount Everest to Antarctica to caves nearly 2,000 metres underground – live tiny critters that have shaped the health of our planet for hundreds of millions of years.

They are known as springtails – an ancient group of invertebrates that evolved along with mosses and lichens dating back to more than 400 million years ago.

By taking a trip into their magical world, you will emerge from the forest with a newfound appreciation of the tiny and easily overlooked wonders that live with us.

What exactly are springtails?

It appears that the earliest written record of springtails is from 350 BCE by the ancient Greek philosopher Aristotle in his published notes History of Animals.

Our knowledge of springtails increased from the 1600s thanks to the improvement in microscopes that allowed scientists to take a closer look at these tiny animals. However, it was not until 1758 that Swedish biologist Carl Linnaeus published the first formal scientific description of springtails.

At first glance these under-appreciated creatures might seem like insects. But they are quite distinct from insects due to their internal mouthparts, less defined body segments, lack of wings, and no real metamorphosis. They range in size from less than a millimetre up to the largest recorded at 17 millimetres.

The largest and most colourful bear a strong resemblance to the “fantastic beasts” of the Harry Potter franchise. They come in lurid red, bright purple and fluorescent yellow, among other colours, and have tiny bumps and hairs covering their bodies, making them look more like colourful sea slugs.

Springtails got their common name from their amazing ability to spring using an organ called the “furcula”. The furcula is a spring-loaded appendage found on the underside of the abdomen and ranges greatly in size. This ability to launch into the air, like a catapult, is incredibly useful to help springtails escape predators.

Their scientific name at the taxonomic level of class – Collembola – is derived from another organ specific to springtails, known as a “collophore”.

The collophore is present in all Collembola and helps them absorb moisture from their environment, which helps with dehydration. This and other adaptations means springtails can live in the driest places on Earth, including hot and cold desert environments.

Maintaining Earth’s ecosystems

Springtails are found in their many thousands in all environments around us, such as forests mangroves, caves, deserts and grasslands. They’re also found in all habitats, such as canopies, surfaces of ponds, soil, leaf litter, mosses and rotting wood. You will even find them in your household compost, gardens, potplants and terrariums.

But for many, their survival can depend on ecosystems being saturated with humidity.

In these environments they are crucially important in regulating bacteria and fungal populations, processing organic matter, as well as prey for other animals.

This makes them vital to maintaining the health of almost all Earth’s ecosystems. As a major element of most habitats on Earth they are found on all continents, including Antarctica.

The evolutionary success of Collembola as a major contributor to healthy ecosystems means they have the potential to indicate when ecosystems are out of balance. That’s why some have been referred to as “canaries in the undergrowth”.

The largest springtails

The Collembola that live within rotting wood are truly spectacular and have been recorded as the largest globally at 17 millimetres.

They were nicknamed “giant Collembola” due to their striking colours and size. In these forest environments they lack a furcula (the spring organ). That may seem odd for a group commonly known as “springtails”, but they have nowhere to spring to in these environments.

Our recent study, published in the Zoological Journal of the Linnean Society, is the largest study to date of Collembola. It was only possible from 25 years of collecting from around the world.

The study proposes major changes within the Neanuroidea superfamily that giant springtails belong to. It dissolves one subfamily (“Uchidanurinae”) that was only aligned by convergent evolution – when species are unrelated but evolve similar features and functions because they occupy similar habitats.

In its place, the study creates two new subfamilies and considers the assignment of almost 200 genera within the Neanuroidea superfamily.

The study shows that the superfamily survived through the KT-boundary mass extinction event about 66 million years ago that wiped out nearly all of the dinosaurs.

It also reveals a distinct divide between groups found in the northern versus southern hemisphere. Our two new subfamilies were dominated by southern hemisphere forest species – Gondwanan remnants that were much more abundant in the past than they are today.

Risking a ‘silent’ mass extinction

Giant springtails living in rotting wood are critically threatened by warming and drying climates in Australia and New Zealand.

While ancient forests continue to disappear or become unsuitable habitat, we continue to lose incredible invertebrate species – many before they have been given scientific names.

This is a “silent” mass extinction – one that threatens the fantastic diversity of life on Earth.

Mark Stevens, Adjunct Associate Professor, School of Biological Sciences, Adelaide University and Cyrille D’Haese, Entomologist, Sorbonne Université

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

Dolphins, whales and seals are highly social animals. Many live in groups, form long-term relationships, and repeatedly interact with the same individuals over years or even decades. Some dolphins have preferred companions, while others move between groups in fluid, ever-changing social networks.

These social lives bring many benefits, from cooperative foraging to protection against predators. However, our new research, published in the journal Mammal Review, shows they also come with a hidden cost: social connections can shape how infectious diseases spread through marine mammal populations.

By bringing together decades of research from around the world, we unravelled that disease outbreaks in the ocean are shaped not only by how many animals are present, but by who interacts with whom.

Disease outbreaks are hard to predict

Infectious diseases are an increasing threat to wildlife populations globally, and marine mammals are no exception. Dolphins, whales and seals face growing pressures from climate change, pollution, habitat disturbance and human activity. These stressors can weaken their immune systems and make animals more vulnerable to infections.

Yet disease outbreaks in marine mammals are often sudden and difficult to explain. One year a population looks healthy; the next, animals are turning up sick or dead.

Some of the most dramatic examples involve morbilliviruses, highly contagious viruses related to measles, which have caused mass die-offs of dolphins and seals in Europe, North America and Australia.

In other cases, skin diseases such as lobomycosis-like disease have spread through dolphin communities, leading to chronic lesions, weakened health and increased vulnerability to other threats.

Part of the challenge is that the ocean hides much of what is happening. Unlike on land, scientists can’t easily observe every interaction, isolate sick individuals, or intervene early when disease begins to spread.

Another reason outbreaks are hard to predict is that disease doesn’t spread evenly through a population. Just as COVID spread faster in some human communities than others, infections in marine mammals often follow social pathways shaped by relationships and behaviour.

Finding the patterns

To understand these patterns more clearly, we conducted a systematic review, carefully gathering and analysing all available scientific studies that examined links between marine mammal social behaviour and infectious disease spread. Our final dataset included 14 studies that were geographically biased toward North America and Australia.

We looked at research on dolphins, whales and seals that used an analytical tool called social network analysis. This is a way of mapping who interacts with whom in a population, much like mapping connections on social media.

Scientists use photographs, observations and long-term monitoring to identify individual animals and track their associations. From this, they can measure how many companions an animal has, how often it interacts with others, and whether it occupies a central position in the social network.

We then examined how these social patterns related to disease presence, outbreak size and transmission risk.

Watch out for ‘super-spreaders’

One of the clearest findings was that highly connected individuals often play an outsized role in disease spread.

These animals, sometimes called “super-spreaders”, interact with many others and can rapidly pass infections through a population.

In dolphin communities, for example, animals with stronger or more frequent social ties were more likely to be associated with disease. In some cases, outbreaks appeared to hinge on just a few socially central individuals.

At the population level, social structure also mattered. While larger groups can initially facilitate disease transmission through frequent and close contact, the way those groups are organised is crucial.

In some populations, the presence of subgroups (semi-stable sets of animals that spend more time interacting with each other than with others) can act as barriers, slowing the spread of disease between clusters.

In other cases, tightly connected subgroups can allow infections to persist or spread more intensely within the population. As a result, a small but highly connected population may be more vulnerable to disease than a larger population with fewer close interactions.

We also uncovered major gaps in knowledge. Most studies focused on a handful of well-studied species, especially bottlenose dolphins, and were concentrated in North America and Australia.

Many threatened species and regions remain poorly studied, limiting our ability to assess global disease risk.

Reducing the risk of disease spread

These findings have important implications for how we monitor and manage wildlife health.

Conservation strategies often focus on counting animals or recording how many are sick or have already died. Our research shows this is not enough. Understanding social relationships and status can help identify which individuals or populations are most vulnerable before an outbreak occurs.

In some cases, targeting monitoring efforts towards socially central animals could provide early warning signs of emerging disease. In others, protecting habitats that support stable social structures may help reduce transmission risk.

There are also ethical and practical benefits. Marine mammals are difficult, and often impossible, to treat once disease is widespread. Prevention, early detection and informed management are therefore crucial.

As environmental pressures on the ocean continue to grow, infectious diseases are likely to become more widespread, frequent and severe. Our work shows that how marine mammals live together may be just as important as the pathogens they face. Understanding animal social lives does not just tell us how dolphins behave; it may be key to protecting their future in a rapidly changing ocean.

The authors would like to acknowledge the contribution of Dr. Mauricio Cantor, Assistant Professor at Oregon State University to this research.

Caitlin Nicholls, PhD Candidate, College of Science and Engineering, Flinders University; Guido J. Parra, Associate Professor, Research Leader of the Cetacean Ecology, Behaviour and Evolution Lab, Flinders University, and Luciana Möller, Associate Professor in Marine Biology, Flinders University

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

Weekend storms and flooding in New South Wales led to the NSW State Emergency Service responding to more than 1,600 incidents across the state.

This follows last week’s flash floods in Victoria, where cars were swept to sea and people raced to escape. Many affected were holidaymakers but even locals were caught unprepared.

Previous flood-preparedness approaches have proved insufficient. Government and risk agencies have relied on top-down approaches that broadcast information to people and then expect them to act on it.

Despite decades of increasingly sophisticated warnings and campaigns, attempting to tell people what to do has delivered uneven and often limited results.

So what actually works?

This question was at the heart of our new paper, published in the Journal of Hydrology, which involved engaging with 641 households in flood-prone areas of Kingston and Darebin in the Greater Melbourne area.

We found a more participatory one-on-one approach leads to behaviour changes that actually reduce risk to people and property. That means really listening to people about what they know and how they feel about flood risk.

What we did

The study used a real-world, before-and-after research design to understand how households decide to reduce flood risk. We used a methodology called Community Engagement for Disaster Risk Reduction, conceived by one of us (Brian Cook) but implemented by an extensive team, which prioritises meaningful human engagement over simply spreading awareness or telling people what to do.

Our researchers worked with households in flood-prone areas, holding one-on-one conversations.

Each household completed an initial survey-interview about their experiences, perceptions, and past actions.

Researchers returned months later to repeat the process and record changes.

By combining survey data with recorded conversations, our study tracked what people actually did over time.

What we found

Our research found people made practical changes to reduce flood risk after these engagements.

What mattered was not being told something, but having the space to talk through their own situation, receive follow-up material, and feel supported in making decisions relevant to them.

One participant reflected:

I can’t recall the detail of the conversation but certainly learned from the links you sent me in reference to the SES and the responses to various potential disasters.

Others described how seeing their home in context helped:

I think the maps and the resources that [your research assistant] sent me are what increased my awareness; I think I looked at the map and where we live, and I think I saw that it was probably the risk of flooding was worse than I thought it was.

For some, the engagement helped them think through

what to do if there’s a flood, acting early, making sure everyone’s safe, just like a bushfire.

Several participants described small but meaningful steps, such as:

I’m getting my emergency box together, so if something happens then I will be prepared or at least know what to grab and run for my life.

The conversations also shaped people’s connections with others. One said they:

got in contact with a couple more neighbours since then, just exchanged numbers so that if they see something happening in our place, or vice versa, that we’ve got a contact for them to call.

Another said:

When it came time to renew my insurance policy, double checked it for our flood cover.

One explained:

I increased my house, contents, and building insurance.

Importantly, participants often framed flood risk as something shared and ongoing, not a problem solved by individual vigilance. One reflected:

There are a lot of leaves in the driveway that I went and swept up and put in my bin and then I thought “I’m never going to get them all in my bin”. I needed to make it a council issue rather than an individual owner’s issue. And if the leaves aren’t swept up, they go in the drains and then we get flooding in the driveway.

Another said:

I have asked the body corporate if they could do some new concreting because the ground has settled and that’s more risky. The water actually can come in [to the house] if we have a lot of rain.

Change emerged through feeling supported, being taken seriously, and acting within everyday constraints.

Where to from here?

In our study, change didn’t occur because people were instructed, persuaded, or repeatedly told what to do.

Nor was it the result of improved messaging, scarier warnings, or more information.

What mattered was participatory learning over time: people being invited into respectful conversations, treated as capable decision-makers, and supported to work through risk in ways that made sense within their own lives.

When people are engaged as partners rather than passive recipients, learning becomes relational, actions feel legitimate, and responsibility is shared across households, neighbours, and institutions.

Is it affordable?

Well, continuing on the current, ineffective path might well be even costlier in the long-term. Governments spend vast amounts on each advertisement campaign, with underwhelming results.

The 2022 floods along Australia’s east coast cost around A$7.7 billion in Queensland alone. If you reduced the damages by 10% you’d have more than $700 million in savings.

Engaging one-on-one with each household in high risk flood zones sounds expensive, but so too are many other tailored services provided by governments in Australia. Think, for instance, of home visits by a midwife or child health nurse after a person gives birth, or an in-home assessment provided by My Aged Care. As a society, we’ve decided those one-on-one engagements, while costly, are worth it.

Our research suggests it’s time we consider a similar approach with disaster risk reduction.

We know what works

Disaster preparedness has for too long persisted with approaches that seek to persuade, instruct, or direct.

But as recent events confirm, disasters do not unfold in neat or predictable ways.

Floods demand judgement, improvisation, and quick decisions made under extreme stress. What’s required isn’t simple compliance with predetermined instructions, but learning that can be adapted and adjusted in the moment.

Crucially, nearly all participants reported enjoying or appreciating the engagements, which helped spread the word and support further community connections.

When people are engaged in conversations that take their circumstances seriously, they build confidence and capacity to respond to unpredictable situations.

This is why participatory engagement and collaboration sit at the heart of the durable risk reduction we will need in an increasingly dangerous future.

Brian Robert Cook, Associate Professor of Geography, The University of Melbourne; Nicholas Harrigan, Senior Lecturer in Quantitative Sociology, Macquarie University, and Peter Kamstra, Post-doctoral Research Fellow of Geography, The University of Melbourne

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

The world is now using so much fresh water amid the consequences of climate change that it has entered an era of water bankruptcy, with many regions no longer able to bounce back from frequent water shortages.

About 4 billion people – nearly half the global population – live with severe water scarcity for at least one month a year, without access to sufficient water to meet all of their needs. Many more people are seeing the consequences of water deficit: dry reservoirs, sinking cities, crop failures, water rationing and more frequent wildfires and dust storms in drying regions.

Water bankruptcy signs are everywhere, from Tehran, where droughts and unsustainable water use have depleted reservoirs the Iranian capital relies on, adding fuel to political tensions, to the U.S., where water demand has outstripped the supply in the Colorado River, a crucial source of drinking water and irrigation for seven states.

Water bankruptcy is not just a metaphor for water deficit. It is a chronic condition that develops when a place uses more water than nature can reliably replace, and when the damage to the natural assets that store and filter that water, such as aquifers and wetlands, becomes hard to reverse.

A new study I led with the United Nations University Institute for Water, Environment and Health concludes that the world has now gone beyond temporary water crises. Many natural water systems are no longer able to return to their historical conditions. These systems are in a state of failure – water bankruptcy.

What water bankruptcy looks like in real life

In financial bankruptcy, the first warning signs often feel manageable: late payments, borrowed money and selling things you hoped to keep. Then the spiral tightens.

Water bankruptcy has similar stages.

At first, we pull a little more groundwater during dry years. We use bigger pumps and deeper wells. We transfer water from one basin to another. We drain wetlands and straighten rivers to make space for farms and cities.

Then the hidden costs show up. Lakes shrink year after year. Wells need to go deeper. Rivers that once flowed year-round turn seasonal. Salty water creeps into aquifers near the coast. The ground itself starts to sink.

That last one, subsidence, often surprises people. But it’s a signature of water bankruptcy. When groundwater is overpumped, the underground structure, which holds water almost like a sponge, can collapse. In Mexico City, land is sinking by about 10 inches (25 centimeters) per year. Once the pores become compacted, they can’t simply be refilled.

The Global Water Bankruptcy report, published on Jan. 20, 2026, documents how widespread this is becoming. Groundwater extraction has contributed to significant land subsidence over more than 2.3 million square miles (6 million square kilometers), including urban areas where close to 2 billion people live. Jakarta, Bangkok and Ho Chi Minh City are among the well-known examples in Asia.

Agriculture is the world’s biggest water user, responsible for about 70% of the global freshwater withdrawals. When a region goes water bankrupt, farming becomes more difficult and more expensive. Farmers lose jobs, tensions rise and national security can be threatened.

About 3 billion people and more than half of global food production are concentrated in areas where water storage is already declining or unstable. More than 650,000 square miles (1.7 million square kilometers) of irrigated cropland are under high or very high water stress. That threatens the stability of food supplies around the world.

Droughts are also increasing in duration, frequency and intensity as global temperatures rise. Over 1.8 billion people – nearly 1 in 4 humans – dealt with drought conditions at various times from 2022 to 2023.

These numbers translate into real problems: higher food prices, hydroelectricity shortages, health risks, unemployment, migration pressures, unrest and conflicts.

How did we get here?

Every year, nature gives each region a water income, depositing rain and snow. Think of this like a checking account. This is how much water we receive each year to spend and share with nature.

When demand rises, we might borrow from our savings account. We take out more groundwater than will be replaced. We steal the share of water needed by nature and drain wetlands in the process. That can work for a while, just as debt can finance a wasteful lifestyle for a while.

Those long-term water sources are now disappearing. The world has lost more than 1.5 million square miles (4.1 million square kilometers) of natural wetlands over five decades. Wetlands don’t just hold water. They also clean it, buffer floods and support plants and wildlife.

Water quality is also declining. Pollution, saltwater intrusion and soil salinization can result in water that is too dirty and too salty to use, contributing to water bankruptcy.

Climate change is exacerbating the situation by reducing precipitation in many areas of the world. Warming increases the water demand of crops and the need for electricity to pump more water. It also melts glaciers that store fresh water.

Despite these problems, nations continue to increase water withdrawals to support the expansion of cities, farmland, industries and now data centers.

Not all water basins and nations are water bankrupt, but basins are interconnected through trade, migration, climate and other key elements of nature. Water bankruptcy in one area will put more pressure on others and can increase local and international tensions.

What can be done?

Financial bankruptcy ends by transforming spending. Water bankruptcy needs the same approach:

• Stop the bleeding: The first step is admitting the balance sheet is broken. That means setting water use limits that reflect how much water is actually available, rather than just drilling deeper and shifting the burden to the future.

• Protect natural capital – not just the water: Protecting wetlands, restoring rivers, rebuilding soil health and managing groundwater recharge are not just nice-to-haves. They are essential to maintaining healthy water supplies, as is a stable climate.

• Use less, but do it fairly: Managing water demand has become unavoidable in many places, but water bankruptcy plans that cut supplies to the poor while protecting the powerful will fail. Serious approaches include social protections, support for farmers to transition to less water-intensive crops and systems, and investment in water efficiency.

• Measure what matters: Many countries still manage water with partial information. Satellite remote sensing can monitor water supplies and trends, and provide early warnings about groundwater depletion, land subsidence, wetland loss, glacier retreat and water quality decline.

• Plan for less water: The hardest part of bankruptcy is psychological. It forces us to let go of old baselines. Water bankruptcy requires redesigning cities, food systems and economies to live within new limits before those limits tighten further.

With water, as with finance, bankruptcy can be a turning point. Humanity can keep spending as if nature offers unlimited credit, or it can learn to live within its hydrological means.

Kaveh Madani, Director of the Institute for Water, Environment and Health, United Nations University

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

Almost two-thirds of Australia is privately owned. But most of our scientific understanding of how threatened species are faring comes from research done on public lands. Traditional biodiversity surveys by professional scientists are time and resource intensive and navigating access to private lands can be tricky.

This means there’s a huge gap in our knowledge amid worsening biodiversity loss. That’s where citizen science comes in. Every year, millions of Australian species records are logged by members of the public using smartphone apps. This flood of data is revolutionising conservation, producing large flows of species data and connecting people to nature.

But does this data better capture species on private land? To find out, our recent research examines almost half a million frog records logged on the Australian Museum’s national FrogID project by citizen scientists in New South Wales. Remarkably, 86% of these records come from private land.

Importantly, these records capture evidence of where threatened species are holding on in privately-held land. The beautiful green and golden bell frog (Litoria aurea) is considered vulnerable at a national level as it’s no longer found on about 90% of its former range. But almost three-quarters of all FrogID recordings of this frog in NSW are on private land.

Recordings with a smartphone

Frogs are one of the most threatened groups of animals on the planet. One in five species of Australian frogs – almost 50 species – are threatened with extinction. Disease, habitat loss and climate change are their greatest threats.

At least four species have already gone extinct – including the unique gastric-brooding frogs – while several others haven’t been seen in decades and are feared extinct. It’s vitally important to track how the surviving 240 plus species are faring.

In our research, we analysed the 496,357 frog records logged in NSW on FrogID between 2017 and 2024.

Private lands make up the majority of New South Wales, and cover almost every habitat type. It stands to reason that many frog species should be found across private land. Our analysis of FrogID data found the diversity of frog species was actually higher on private lands than on public lands, which include national parks and other protected areas, once we accounted for differences in aridity and surveying efforts.

In addition, the frog species recorded on private and public lands weren’t the same. Two species were recorded only on private lands and six only on public land.

As we expected, we found that citizen science more comprehensively surveyed public land than surveys by professional scientists, but the difference was more dramatic than expected. Data from professional surveys covered 19% of NSW, while citizen scientists using FrogID covered 35%. There were nearly ten times as many FrogID records as professional records over the same time period.

But the clearest difference was in private lands. A remarkable 86% of all FrogID records came from private lands, compared to only 59% of records obtained via traditional methods.

Frog calls after floods

One of the biggest boons of citizen science is that it can help overcome many of the logistical obstacles associated with traditional professional surveys, particularly for frogs.

Most of the NSW FrogID records come from urban and suburban areas with high human population density. But the data showed an increasing number of landholders in regional and remote areas are using FrogID to record their local frogs.

Obtaining records of frogs from these areas via traditional surveys has long presented a major challenge for scientists. That’s because many frog species in arid and semi-arid areas only become active after heavy rains. But these areas can become inaccessible to scientists due to flooded roads.

By opportunistically recording frogs when they’re active, landholders are providing the vital information we need to better understand poorly-known frog species such as burrowing frogs from the Cyclorana genus and the charismatic crucifix frog (Notaden bennettii).

Private lands are vital to conservation

It’s common to think that threatened species will be restricted to protected areas such as national parks. Our research adds to the body of evidence showing this isn’t the case.

We found 20 of the 24 NSW threatened frog species we analysed had been recorded on private land. In fact, a third of all threatened frog species were predominantly recorded on private land, while three threatened frog species had over 70% of recordings logged on private land.

One such species is Sloane’s froglet (Crinia sloanei), a tiny frog from inland New South Wales and northern central Victoria. Habitat loss has greatly reduced its range. It’s now considered endangered nationally. We found 96% of records were on private land, largely around Albury–Wodonga on the Victorian border. Similarly, the nationally vulnerable green and golden bell frog was largely recorded on private lands.

How can you help?

Private lands are now seen as increasingly important in conserving wildlife, including threatened species. The good news is, this means landholders and citizen scientists can make a direct difference.

Protecting or creating wildlife habitats on your property can make a very real contribution to biodiversity conservation. Even humble farm dams can support threatened frog species.

While citizen science has greatly improved our knowledge of frog species across Australia including poorly-sampled areas, scientists still need more data on Australia’s frogs.

Recording and uploading the calls of any frogs you hear using the FrogID app is a simple and effective way of adding to our collective knowledge of these remarkable amphibians. The more data sources we have, the better. Citizen scientists are giving real-time updates of where frogs live and how their distributions are changing over time. These data in turn help focus efforts to bring back threatened frog species from the brink of extinction.

Grace Gillard, Technical Officer, Herpetology, Australian Museum and Jodi Rowley, Curator, Amphibian & Reptile Conservation Biology, Australian Museum, UNSW Sydney

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

In 1830, the Palawa people were in the midst of their guerilla war against the British colonists taking their land in what is now Tasmania. After flaring in the mid-1820s, intensifying violence had claimed hundreds of First Nations and settler lives. In response, the Governor of Van Diemen’s Land, Sir George Arthur, commissioned the preacher George Augustus Robinson to seek conciliation.

Guided by Nuenonne woman Truganini and her cleverman husband Woureddy, Robinson travelled southwest across Tasmania to persuade the largely isolated Toogee nation to be relocated to a Christian mission. They were assured they would eventually be allowed to return. The promise was broken. Almost 200 members of the Toogee and other Lutruwita nations were exiled to Flinders Island, where most died.

The consequences of Robinson’s empty promise have lingered ever since, from the erosion of Palawa culture to the abrupt end to millennia of cultural burning.

In our time, Tasmania’s west is thought of as wilderness – wild and lightly populated. Dry lightning storms triggered massive fires in 2013, 2016, 2019 and 2025, burning areas unused to fire.

To find out whether these fires were been made worse by the end of Indigenous cultural burning, we turned to Robinson’s detailed journals. In our new research, we show Robinson made very rapid progress across treeless areas. Many of these are now dense scrub. This is the first time this scrubby thickening has been shown to have occurred at regional scale in Tasmania.

With dry lightning storms projected to increase as the world heats up, our findings suggest a return to cultural burning in treeless areas could be one way to reduce the risk of these uncontrolled bushfires.

Rapid travel through open country

The forced removal of many Palawa by British authorities, and a poor ethnographic record, has made it hard for scientists and land managers to understand how and where Country was managed in Tasmania. Understanding early use of fire is of particular importance in western Tasmania, where national parks preserve many forests and grasslands.

This is why we turned to Robinson’s journals. While Robinson’s role as “conciliator” had catastrophic consequences for Palawa, his journals are one of the few detailed written records of Tasmanian’s ancient cultural landscapes. We analysed the accounts of his 1830 trip from Bathurst Harbour in the far south to Macquarie Harbour and up to Cape Grim, as well as his subsequent 1833 journey to the southwest – around 464 kilometres in total.

The way Robinson describes the vegetation of almost two centuries ago is broadly consistent with maps of current vegetation. Most of his routes (72%) went across treeless areas such as buttongrass plains or sedge and shrub-covered moorlands, or followed what Robinson called “native roads” – pathways through forests created through intentional burning.

Tasmania’s treeless areas are highly fire-prone. Despite this, about a third of these treeless areas haven’t burned in the last half-century.

Over time, these long-unburned treeless areas become denser and denser. Tasmanian bushwalkers describe walking here as “scrub-bashing”, as it involves fighting through thickets of vines, shrubs and dense undergrowth.

A striking feature of Robinson’s journeys was how quickly he moved across landscapes now notoriously difficult for modern day bushwalkers. Retracing Robinson’s west coast routes is a challenge even for well-equipped bushwalking groups. The distance Robinson travelled in one day would now take two or three days.

The phenomenon where moorlands turn into impassable scrub is well known in Tasmania. Cape Pillar in the southeastern Tasman National Park is now covered in thick scrub. Early colonial observers saw instead an open landscape.

While some ecological theories suggest increased shrub density will rapidly transform treeless areas to forests, this isn’t the case in this region.

Robinson’s journals and other historical sources leave no doubt the frequent low-intensity fires set by First Nations kept treeless landscapes open and passable in Tasmania.

Palawa burning of treeless areas required skilful coordination with seasonal weather and intimate knowledge of terrain to avoid destroying organic soils and fire sensitive alpine and rainforest vegetation. After cultural burning ended, large and more damaging bushfires increased. These have had a catastrophic impact on fire-sensitive plants such as King Billy pine.

Wild, remote – and more prone to fire?

Visitors are often struck with how western Tasmania’s wild, remote landscapes mix large treeless areas with forests and alpine plants. This diversity of vegetation brings with it a complex fire ecology. Ancient trees such as southern beech (Nothofagus) and pencil pines (Athrotaxis) dating back to the Gondwanan era are often surrounded by flammable eucalypt forests and sedgelands.

These areas are often wet. Rainfall is high and many soils are saturated. Plant communities here grow on peaty soils with organic surface layers. When these organic layers dry out, the soil itself can burn, triggering a cascade of degradation through soil loss, erosion and slower plant growth.

Lightning is a major cause of bushfires, as treeless regions are particularly prone to igniting after a strike. Massive dry lightning storms across Tasmania are becoming more common.

Bringing back fire?

The fires started by dry lightning storms can grow very fast, as lightning can strike in several places in quick succession, far from human settlements. It’s practically impossible for land managers to detect these fires and put them out while small. This year, a huge 100,000 hectare fire began when over 1,200 lightning strikes started dozens of individual fires.

Fuel reduction burns on treeless areas can reduce the risk of lightning starting a fire and make any ignitions easier to fight.

As the area is World Heritage listed, authorities will have to consider the interests of contemporary Palawa people, who already manage significant places such as Kutikina and Wargata Mina caves and want a self-determined approach to cultural burning.

There’s still much to rediscover about Palawa use of fire. Authorities will have to learn how to burn grasslands, moorlands and sedgelands while avoiding burning the peat beneath, how to manage tracts of long unburned scrub, and how to create landscape mosaics to maximise habitat for different species.

Doing this will require a partnership between fire authorities and First Nations practitioners. As climate change intensifies, this task is only getting harder and more urgent.

David Bowman, Professor of Pyrogeography and Fire Science, University of Tasmania and Greg Lehman, Professorial Fellow, Institute of Indigenous Knowledges, University of Tasmania

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

Floods, droughts and heatwaves continue to dominate headlines around the world and in Australia.

In the past few days, hundreds of bushfires have ignited in south-east Australia during an extreme heatwave. And communities in north Queensland have been lashed by heavy rain and flash flooding from ex-tropical Cyclone Koji. This is the seventh cyclone so far this season.

Behind these disasters is a deeper and less visible influence: ongoing shifts in the global water cycle. This is the process by which water evaporates, falls as rain and snow, and ultimately evaporates again. Our latest report shows how changes in rainfall, air temperature and humidity combined to amplify water-related disasters across the world in 2025.

These floods and fires are not simply isolated weather extremes, but signs of a water cycle that is being increasingly destabilised by global warming.

Why the water cycle is changing

The global water cycle connects the atmosphere, land, oceans and ice. Water evaporates from the land and seas, falling as rain and snow. This feeds glaciers, rivers, lakes and groundwater and finally either evaporates again or flows to the ocean. This cycle is driven by the energy from the sun. And as the planet warms, it is becoming more powerful and more erratic.

Global temperatures over land in 2025 were only slightly lower than a record-breaking year in 2024. This makes the last three years the hottest on record, in line with rapid global warming.

Higher temperatures accelerate evaporation from soil, vegetation and inland waters, producing dry conditions more quickly than before. At the same time, warmer air can hold more moisture, which increases the potential for intense rainfall. Together, these processes intensify both floods and droughts, sometimes in rapid succession.

Rainfall followed by heat

In 2025, many regions of the globe experienced this pattern: extreme rainfall followed closely by heat and drying. Scientists describe these abrupt swings between dry and wet extremes as “climate whiplash”.

Climate whiplash occurs when wet and dry extremes follow one another so quickly that ecosystems, infrastructure and communities struggle to cope. One example in 2025 was the severe wildfires in Spain and Portugal.

A wetter-than-average spring promoted strong vegetation growth across parts of the Iberian Peninsula. Then a sudden heatwave was followed by rapid loss of soil moisture. The rapidly-dried vegetation fuelled severe wildfires later in the season.

Queensland floods

Australia has also weathered shifts in the water cycle in the past year. In February 2025, Cyclone Alfred landed in southeast Queensland. It is not unprecedented to have cyclones so far south, but it was the first time in 50 years. In the following months, the rest of Queensland was hit hard by torrential rains and severe flooding.

Also in early 2025, tropical low-pressure systems near north Queensland produced rainfall totals comparable to those in a cyclone. More than 1,000 millimetres of rain fell within days in some areas, and Townsville recording its wettest month on record.

The event caused widespread damage to homes, transport and essential services, with economic losses exceeding $A1.2 billion.

The wet conditions, combined with high temperatures, also triggered an unprecedented outbreak of melioidosis. This is a disease caused by bacteria that occur naturally in soil and freshwater but can become dangerous when rainfall and flooding bring them to the surface. By May, Queensland Health had recorded 221 cases and 31 deaths, making it the largest outbreak in the state’s history.

The shows how water cycle extremes affect natural and human systems. Torrential rains and flooding has become a regular occurrence in Queensland and northern New South Wales.

Global instability

Several other events in 2025 revealed how different parts of the water cycle are becoming more unstable. In the Himalayas a series of unprecedented glacial lake floods occurred within just a few months following warm conditions.

Meanwhile, a rare cyclone close to the equator took Indonesian and Malaysian communities by surprise.

The increasing frequency of tropical cyclones in historically uncommon locations reflects how warming oceans and shifting atmospheric conditions are expanding the reach of water-related hazards.

The human and economic toll

Globally, our report shows that water-related disasters in 2025 were associated with nearly 5,000 deaths, displaced around 8 million people, and caused economic losses exceeding US$360 billion (A$536 billion).

In Europe, prolonged heatwaves were linked to many thousands of heat-related deaths. And in South and Southeast Asia, flooding displaced millions in countries such as the Philippines, Thailand, Malaysia, and Bangladesh.

This show how different parts of the water cycle – from the atmosphere to soil conditions, river flows and surface water – can influence ongoing global warming.

Being prepared helps

Our report finds that preparedness really matters. Early-warning systems and evacuation planning saved many lives in several major floods, such as those on the west coast of the US in December 2025. However, severe disruption and economic damage still occurred where infrastructure had been designed for stable, historical conditions.

Conditions in the global water cycle at the end of 2025 point to greater drought risk in parts of the Mediterranean, the Horn of Africa, Brazil and Central Asia in 2026. On the other hand, wet conditions mean flood and landslide risks remain high in the Sahel, south of the Sahara Desert, southern Africa, northern Australia and much of Asia.

As climate instability continues, the global water cycle is likely to become even more variable. Understanding how water moves through the climate system – and how quickly it can shift from one extreme to another – will help us reduce the impacts of future disasters. Managing both heat and water extremes will be key to adapting to a rapidly warming world.

Albert Van Dijk, Professor, Water and Landscape Dynamics, Fenner School of Environment & Society, Australian National University

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

Beneath Antarctica’s Ross Ice Shelf lies one of the least measured oceans on Earth – a vast, dark cavity roughly twice the volume of the North Sea.

This hidden ocean matters because it is the ice sheet’s Achilles heel. The ice sheet is the continent’s enormous, kilometres-thick mass of land-based ice, while the ice shelf is the floating platform that fringes it.

If warmer water reaches the underside of the shelf, it can melt the ice that holds back millions of cubic kilometres of Antarctic ice, with consequences for global sea levels.

Yet almost everything we know about this cavity has come from brief snapshots at its edges. Until now, no one had captured a long, continuous record from its central heart. Our newly published study set out to change that.

Inside Antarctica’s least-measured ocean

Ice shelves act as buttresses for Antarctica’s 30 million cubic kilometres of ice, built up over millions of years. The Ross Ice Shelf is the largest, among the coldest and most southerly, and perhaps the most sheltered from a warming ocean.

It spans both West and East Antarctica, where dozens of giant glaciers merge to form a wedge of ice 300 to 700 metres thick that flows northward, melting from below and calving the world’s largest icebergs.

When studying the ocean, snapshots are useful, but long time series are far more powerful. They reveal the rhythms of currents, eddies, tides and mixing, and how these interact with a warming climate. Beneath Antarctic ice shelves, where measurements are vanishingly rare, developing such records is essential.

Our study describes a four-year record of ocean processes beneath the middle of the Ross Ice Shelf, where the ice is 320 metres thick and the ocean below it 420 metres deep.

Most expeditions focus on the edges of ice shelves. We needed to understand what happens at their centre: so that is where we went.

The work was part of a large, multi-year project that began in 2016 with exploratory missions and ice-drilling trials and ended in 2022 when we finally lost contact with instruments suspended from the underside of the ice.

Once the drilling team reached the ocean – despite bad weather and the technical challenges of working in such a remote, extreme environment – we were able to deploy our instruments. These precision devices reported temperature, currents and salinity via satellite. We expected them to last two years before succumbing to cold or transmission failure. Instead, most continued to operate for more than four years, producing a uniquely long and remote record.

The new analysis shows that water properties vary systematically through the year, far from the open ocean and its seasons. The changes in temperature and salinity are subtle, but in a cavity shielded from winds and cold air even small shifts can have large implications.

Our work also reveals how variations in the central cavity align with changes in the Ross Sea Polynya – a wind-swept, ice-free area hundreds of kilometres away where high-salinity water forms. As Antarctic sea ice changes, this connection to the cavity will respond in ways we have not yet fully considered.

Perhaps most intriguingly, the data show persistent layering of water with different properties within the cavity. This unusual structure was detected in the very first measurements collected there in 1978 and remains today. While much remains to be learned, our results indicate the layers act as a barrier, isolating the ice shelf underside from deeper, warmer waters.

What melting ice brings home

Much recent cavity research has treated the ice shelf as a middleman, passing ocean warming through to the ice sheet. Work like ours is revealing a more complex set of relationships between the cavity and other polar systems.

One of those relationships is with sea ice. When sea ice forms around the edges of an ice shelf, some of the cold, salty water produced as a by-product flows into the cavity, moving along the seafloor to its deepest, coldest reaches. Paradoxically, this dense water can still melt the ice it encounters. We know very little about these currents.

Changes to the delicate heat balance in ice-shelf cavities are likely to accelerate sea-level rise. Coastal communities will need to adapt to that reality. What remains less understood are the other pathways through which Antarctic change will play out.

Impacts from ice sheets unfold over decades and centuries. On similar timescales, changes around Antarctica will alter ocean properties worldwide, reshaping marine ecosystems and challenging our dependence on them.

In the near term, we can expect shifts in southern weather systems and Southern Ocean ecosystems. Fisheries are closely linked to sea-ice cover, which in turn is tied to ocean temperatures and meltwater.

Weather and regional climate feel even closer to home. A glance at a weather map of the Southern Ocean shows the inherent wobble of systems circling the globe. These patterns influence conditions in New Zealand and southern Australia and they are already changing.

As ice shelves and sea ice continue to evolve, that change will intensify. Ice shelves may seem distant, but through their ties to the atmosphere and ocean we share a common future.

Craig Stevens, Professor in Ocean Physics, University of Auckland, Waipapa Taumata Rau; National Institute of Water and Atmospheric Research (NIWA); Christina Hulbe, Professor and Dean of the School of Surveying (glaciology specialisation), University of Otago, and Yingpu Xiahou, PhD Candidate in Physical Oceanography, University of Auckland, Waipapa Taumata Rau

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

Our planet has experienced dramatic climate shifts throughout its history, oscillating between freezing “icehouse” periods and warm “greenhouse” states.

Scientists have long linked these climate changes to fluctuations in atmospheric carbon dioxide. However, new research reveals the source of this carbon – and the driving forces behind it – are far more complex than previously thought.

In fact, the way tectonic plates move about Earth’s surface plays a major, previously underappreciated role in climate. Carbon doesn’t just emerge where tectonic plates meet. The places where tectonic plates pull away from each other are significant too.

Our new study, published today in the journal Communications, Earth and Environment sheds light on how exactly Earth’s plate tectonics have helped to shape global climate over the past 540 million years.

Peering deep within the carbon cycle

At the boundaries where Earth’s tectonic plates converge, we get chains of volcanoes known as volcanic arcs. Melting associated with these volcanoes unlocks carbon that’s been trapped inside rocks for thousands of years, bringing it to Earth’s surface.

Historically, it’s been thought these volcanic arcs were the primary culprits of injecting carbon dioxide into the atmosphere.

Our findings challenge that view. Instead, we suggest that mid-ocean ridges and continental rifts – locations where the tectonic plates spread apart – have played a much more significant role in driving Earth’s carbon cycles throughout geological time.

This is because the world’s oceans sequester vast quantities of carbon dioxide from the atmosphere. They store most of it within carbon-rich rocks on the seafloor. Over thousands of years, this process can produce hundreds of metres of carbon-rich sediment at the bottom of the ocean.

As these rocks then move about the Earth driven by tectonic plates, they may eventually intersect subduction zones – places where tectonic plates converge. This releases their carbon dioxide cargo back into the atmosphere.

This is known as the “deep carbon cycle”. To track the flow of carbon between Earth’s molten interior, oceanic plates and the atmosphere, we can use computer models of how the tectonic plates have migrated through geological time.

What we discovered

Using computer models to reconstruct how Earth moves carbon stored on tectonic plates, we were able to predict major greenhouse and icehouse climates over the last 540 million years.

During greenhouse periods – when Earth was warmer – more carbon was released than trapped within carbon-carrying rocks. In contrast, during icehouse climates, the carbon sequestration into Earth’s oceans dominated, lowering atmospheric carbon dioxide levels and triggering cooling.

One of the key takeaways from our study is the critical role of the deep-sea sediments in regulating atmospheric carbon dioxide. As Earth’s tectonic plates slowly move, they carry carbon-rich sediments, which are eventually returned into Earth’s interior through a process known as subduction.

We show that this process is a major factor in determining whether Earth is in a greenhouse or icehouse state.

A shift in understanding the role of volcanic arcs

Historically, the carbon emitted from volcanic arcs has been considered one of the largest sources of atmospheric carbon dioxide.

However, this process only became dominant in the last 120 million years thanks to planktic calcifiers. These little ocean critters belong to a family of phytoplankton whose main talent lies in converting dissolved carbon into calcite. They are responsible for sequestering vast amounts of atmospheric carbon into carbon-rich sediment deposited on the seafloor.

Planktic calcifiers only evolved about 200 million years ago, and spread through the world’s oceans about 150 million years ago. So, the high proportion of carbon spewed into the atmosphere along volcanic arcs in the past 120 million years is mostly due to the carbon-rich sediments these creatures created.

Before this, we found that carbon emissions from mid-ocean ridges and continental rifts – regions where tectonic plates diverge – actually contributed more significantly to atmospheric carbon dioxide.

A new perspective for the future

Our findings offer a new perspective on how Earth’s tectonic processes have shaped, and will continue to shape, our climate.

These results suggest Earth’s climate is not just driven by atmospheric carbon. Instead, the climate is influenced by the intricate balance between carbon emissions from Earth’s surface and how they get trapped in sediments on the seafloor.

This study also provides crucial insights for future climate models, especially in the context of current concerns over rising carbon dioxide levels.

We now know that Earth’s natural carbon cycle, influenced by the shifting tectonic plates beneath our feet, plays a vital role in regulating the planet’s climate.

Understanding this deep time perspective can help us better predict future climate scenarios and the ongoing effects of human activity.

Ben Mather, ARC Early Career Industry Fellow, School of Geography, Earth and Atmospheric Sciences, The University of Melbourne; Adriana Dutkiewicz, ARC Future Fellow, Sedimentology, University of Sydney; Dietmar Müller, Professor of Geophysics, University of Sydney, and Sabin Zahirovic, ARC DECRA Fellow, School of Geosciences, University of Sydney

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

Over Christmas, vegetables, bananas and insulation foam washed up on beaches along England’s south-east coast. They were from 16 containers spilled by the cargo ship Baltic Klipper in rough seas. In the new year, a further 24 containers fell from two vessels during Storm Goretti, with chips and onions among the goods appearing on the Sussex shoreline.

For most people this is a nuisance – or perhaps a bit of fun. For oceanographers like me, who study tides and currents, it is also an accidental experiment – a rare chance to watch the ocean move things around in real time. Think of it as a very large message in a bottle.

In reality, cargo has been falling off ships since traders first went to sea. What has changed is that, in the modern world, most goods are transported in standardised containers. Apart from oil, gas, vehicles, bulk grain, aggregates – and people – pretty much everything is moved this way.

More than 250 million containers are shipped around the world each year, and it is likely that over 80% of goods in your home travelled at some point in a container by sea.

Losses are rare. Industry group the World Shipping Council estimates that over the past ten years an average of 1,274 containers a year have been lost globally, out of hundreds of millions transported. This figure does vary: in 2020 a single huge ship the ONE Apus lost around 1,800 containers of its 14,000 load in a Pacific storm, while in 2024 global losses were estimated at just 576.

Ducks go global

Some losses make the news in unexpected ways. In January 1992, 12 containers washed off the Ever Laurel in the North Pacific. One of these contained 28,800 bath toys – plastic beavers, frogs, turtles and ducks – which spilled into the ocean and washed up on beaches around the Pacific over the next decade or more.

Curt Ebbesmeyer and James Ingraham, oceanographers from Seattle, tracked these so-called “friendly floatees” around the world and used them to improve scientific models of ocean circulation. In more recent years I’ve looked at the progress of these floatees into the Arctic and beyond.

Not all cargoes are this benign or useful. In January 2007, the MSC Napoli was hit by a major storm in the Channel and lost 114 containers, 80 of which washed up on beaches around Branscombe in Devon. Containers of wine, BMW motorbikes and perfumes drew locals to scour the beach for prizes but there were also far more sinister containers of explosives, weed killers, fertilisers and acid.

Both the cargoes and the containers themselves pose serious risks. Chemicals can destroy habitats, while containers can sometimes lurk one or two metres below the surface, kept semi-buoyant by trapped air, making them difficult to detect and capable of causing serious damage in a collision.

Designed for speed – not 100% security

Modern container ships are designed for speed and efficiency in port. A single 400-metre vessel can carry up to 25,000 containers, many towering high above deck like a block of flats. The containers interlock and are secured using industry standard fixings – one reasons cranes are able to rapidly move them around a port. In severe storms, however, the forces involved can exceed what the fixings are designed to withstand, and containers can be dislodged, particularly those at the edge.

It is almost impossible to secure cargo 100% safely. To do so would mean smaller ships, with cargo held internally, reversing decades of efficiency gains. That would mean far more ships required to move the same volume of goods, higher costs for consumers, great fuel use per tonne of goods, and a higher overall risk of accidents. It would also clog up ports around the world.

The English Channel is one of the busiest shipping lanes in the world and is regularly battered by storms. Southampton, the UK’s second busiest container port, is also one of only a few worldwide that can accommodate the largest container ships. It is therefore no surprise that container losses are often visible along England’s south coast.

Looking ahead, the risks are unlikely to diminish. Climate change is intensifying storms as oceans warm, while international trade continues to grow and ships become ever larger.

The ship owners – usually through their insurance companies – are responsible for cleaning up spills, but the system only works if the losses are reported. Until now, containers lost at sea have often gone unreported or their contents have been barely documented.

However, from January 1 2026, new international rules introduced by the World Shipping Council working with the International Maritime Organisation (the UN Agency responsible for shipping) will require ship owners to report all cargo losses and their contents. While this may not prevent containers being lose at sea, it should improve tracking, recovery and accountability.

If you see a container on a beach, resist the temptation to see it as an early Christmas present. You should report it immediately to the coastguard – scavenging wrecks can count as theft. In the UK, who owns what washes up is decided by a single civil servant with the grand title of the Receiver of Wreck. Critically, that container may contain a far less pleasant cargo that could ruin your Christmases for years to come.

Simon Boxall, Senior Lecturer in Ocean and Earth Science, University of Southampton

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