The Australian government is poised to introduce a new domestic gas reservation policy on the east coast. The plan is meant to tackle growing concerns around spiking gas prices and domestic supply. Large gas producers in Queensland export the vast majority of their gas to overseas buyers and long-reliable wells in Bass Strait are running empty.

While details are still forthcoming, the broad brushstrokes are clear. Gas reservation policies work because, in this instance, they require east coast liquefied natural gas (LNG) producers to reserve specific volumes for domestic use rather than exporting them.

It’s not unexpected. The government flagged the need for major reform following a sector-wide review of the gas market. Domestic gas prices have tripled in a decade as producers focus on export markets. Price rises have hit big users hard and driven up power prices, as gas is now the most expensive way to produce electricity.

High gas prices have pushed the government to bail out gas-reliant smelters and steelworks. Price shocks have forced industries and households to look for cheaper electric options.

The move comes after Australia’s energy market operator warned the east coast will soon face a gas shortfall.

If designed appropriately, the policy has a real chance of forcing exporters to boost domestic supply. This could cut the link between domestic gas prices and much higher global LNG prices. Something has to be done – gas supply stress is real and worsening. It won’t address all market and infrastructure issues facing the east coast gas market, such as a shortage of pipeline capacity linking Queensland and the southern states.

What would a gas reservation policy look like?

After an energy crisis in the 1980s, Western Australia introduced its own gas reservation policy which required producers to reserve 15% of gas for domestic use.

But no such scheme has applied on the east coast. Instead, there’s been a mix of regulatory reforms, voluntary industry deals and state-level proposals. Former Liberal leader Peter Dutton took a plan to reserve gas to this year’s election, though it lacked detail on the mechanics, infrastructure constraints and who would bear the costs.

What the Albanese government is proposing would apply only to the east coast, which has a separate gas network, and only to gas that hasn’t already been committed under long-term export contracts.

The proposed scheme would likely build on existing regulatory frameworks such as the Australian Domestic Gas Security Mechanism and Mandatory Gas Code, but would apply more directly to east-coast exporters which are largely located in Queensland.

The plan is to link the new scheme to a broader regulatory overhaul as part of the government’s Future Gas Strategy launched last year. The strategy is meant to ensure gas remains affordable and to manage supply and demand as Australia shifts to clean energy.

Three pillars

While full details are yet to be announced, we know there will be three main elements: a mandatory reservation volume, a gas security incentive, and competitive domestic pricing.

The mandatory reservation will require gas producers to reserve a portion of their supply for the domestic market, likely to be around 50–100 petajoules in its first year of operation. That would represent roughly 10–20% of the 520PJ burned in gas power stations as of 2021–22.

Efforts by previous governments have been voluntary. This will be mandatory, forcing producers to reserve a specific percentage for the domestic market. Once introduced, the scheme will significantly increase dwindling east coast supplies.

The gas security incentive is a strategic move to encourage producers to offer more gas on the domestic market. It will likely work by levying a charge to gas exports, excluding those under long-term contract. The charge is, however, a temporary measure and when a producer fulfils its annual obligation to supply gas to the domestic market, the levy will be returned to them.

The scheme is likely to include competitive domestic pricing to ensure domestic purchasers can buy gas at prices that reflect the cost of production rather than the substantially higher international export prices. This is likely to stabilise gas prices and significantly reduce our dependence on volatile international markets.

Who bears the cost?

Gas producers are not likely to be happy, given they will have to sell gas more cheaply. The peak oil, gas and coal body, Australian Energy Producers, has previously warned against interventionist policies such as mandatory reservation schemes. It says there is a risk of undermining investor confidence and discouraging exploration and production.

The government doesn’t seem concerned about these claims. Rising energy prices have a political cost. Well-designed mandatory reservation scheme will go some way to tackling cost-of-living issues by improving domestic supply security and alleviating some price pressures.

It makes sense to take advantage of Australia’s enormous gas reserves and tackle the looming shortfall and pricing concerns. Disconnecting the domestic east coast market from global LNG price volatility is rational.

Ideally, the forthcoming scheme will form just part of a broader structural overhaul of the gas market including infrastructure, contracting, investment incentives and demand-management reforms.

Samantha Hepburn, Professor of Law, Deakin University

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

You might think of Australia’s arid centre as a dry desert landscape devoid of aquatic life. But it’s actually dotted with thousands of rock holes – natural rainwater reservoirs that act as little oases for tiny freshwater animals and plants when they hold water.

They aren’t teeming with fish, but are home to all sorts of weird and wonderful invertebrates, important to both First Nations peoples and desert animals. Predatory damselflies patrol the water in search of prey, while alien-like water fleas and seed shrimp float about feeding on algae.

Often overlooked in favour of more photogenic creatures, invertebrates make up more than 97% of all animal species, and are immensely important to the environment.

Our new research reveals 60 unique species live in Australia’s arid rock holes. We will need more knowledge to protect them in a warming climate.

Overlooked, but extraordinary

Invertebrates are animals without backbones. They include many different and beautiful organisms, such as butterflies, beetles, worms and spiders (though perhaps beauty is in the eye of the beholder!).

These creatures provide many benefits to Australian ecosystems (and people): pollinating plants, recycling nutrients in the soil, and acting as a food source for other animals. Yet despite their significance, invertebrates are usually forgotten in public discussions about climate change.

Freshwater invertebrates in arid Australia are rarely the focus of research, let alone media coverage. This is due to a combination of taxonomic bias, where better-known “charismatic” species are over-represented in scientific studies, and the commonly held misconception that dry deserts are less affected by climate change.

Oases of life

Arid rock-holes are small depressions that have been eroded into rock over time. They completely dry out during certain times of year, making them difficult environments to live in. But when rain fills them up, many animals rely on them for water.

When it is hot, water presence is brief, sometimes for only a few days. But during cooler months, they can remain wet for a few months. Eggs that have been lying dormant in the sediments hatch. Other invertebrates (particularly those with wings) seek them out, sometimes across very long distances. In the past, this variability has made ecological research extremely difficult.

Our new research explored the biodiversity in seven freshwater rock holes in South Australia’s Gawler Ranges. For the first time, we used environmental DNA techniques on water samples from these pools.

Similar to forensic DNA, environmental DNA refers to the traces of DNA left behind by animals in the environment. By sweeping an area for eDNA, we minimise disturbance to species, avoid having to collect the animals themselves, and get a clear snapshot of what is – or was – in an ecosystem. We assume that the capture window for eDNA goes back roughly two weeks.

These samples showed that not only were these isolated rock holes full of invertebrate life, but each individual rock hole had a unique combination of animals in it. These include tiny animals such as seed shrimp, water fleas, water boatman and midge larvae. Due to how dry the surrounding landscape is, these oases are often the only habitats where creatures like these can be seen.

Culturally significant

These arid rock holes are of great cultural significance to several Australian First Nations groups, including the Barngarla, Kokatha and Wirangu peoples. These are the three people and language groups in the Gawler Ranges Aboriginal Corporation, who hold native title in the region and actively manage the rock holes using traditional practices.

As reliable sources of freshwater in otherwise very dry landscapes, these locations provided valuable drinking water and resting places to many cultural groups. Some of the managed rock holes hold up to 500 litres of water, but elsewhere they are even deeper.

Diverse practices were traditionally developed to actively manage rock holes and reliably locate them. Some of these practices — such as regular cleaning and limiting access by animals — are still maintained today.

Threatened by climate change

Last year, Earth reached 1.5°C of warming above pre-industrial levels for the first time. Australia has seen the dramatic consequences of global climate change firsthand: increasingly deadly, costly and devastating bushfires, heatwaves, droughts and floods.

Climate change means less frequent and more unpredictable rainfall for Australia. There has been considerable discussion of what this means for Australia’s rivers, lakes and people. But smaller water sources, including rock holes in Australia’s deserts, don’t get much attention.

Australia is already seeing a shift: winter rainfall is becoming less reliable, and summer storms are more unpredictable. Water dries out quickly in the summer heat, so wildlife adapted to using rock holes will increasingly have to go without.

Drying out?

Climate change threatens the precious diversity supported by rock holes. Less rainfall and higher temperatures in southern and central Australia mean we expect they will fill less, dry more quickly, and might be empty during months when they were historically full.

This compounds the ongoing environmental change throughout arid Australia. Compared with iconic invasive species such as feral horses in Kosciuszko National Park, invasive species in arid Australia are overlooked. These include feral goats, camels and agricultural animal species that affect water quality. Foreign plants can invade freshwater systems.

Deeper understanding

Many gaps in our knowledge remain, despite the clear need to protect these unique invertebrates as their homes get drier. Without a deeper understanding of rock-hole biodiversity, governments and land managers are left without the right information to prevent further species loss.

Studies like this one are an important first step because they establish a baseline on freshwater biodiversity in desert rock holes. With a greater understanding of the unique animals that live in these remote habitats, we will be better equipped to conserve them.

Brock A. Hedges, Research Affiliate, University of Adelaide; James B. Dorey, Lecturer in Biological Sciences, University of Wollongong, and Perry G. Beasley-Hall, Postdoctoral fellow, University of Adelaide

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

Sometimes, we get lucky in science. In this case, an oceanographic float we deployed to do one job ended up drifting away and doing something else entirely.

Equipped with temperature and salinity sensors, our Argo ocean float was supposed to be surveying the ocean around the Totten Glacier, in eastern Antarctica. To our initial disappointment, it rapidly drifted away from this region. But it soon reappeared further west, near ice shelves where no ocean measurements had ever been made.

Drifting in remote and wild seas for two-and-a-half years, the float spent about nine months beneath the massive Denman and Shackleton ice shelves. It survived to send back new data from parts of the ocean that are usually difficult to sample.

Measurements of the ocean beneath ice shelves are crucial to determine how much, and how quickly, Antarctica will contribute to sea-level rise.

What are Argo ocean floats?

Argo floats are free-floating robotic oceanographic instruments. As they drift, they rise and fall through the ocean to depths of up to 2 kilometres, collecting profiles of temperature and salinity. Every ten days or so they rise to the surface to transmit data to satellites.

These floats have become a mainstay of our global ocean observing system. Given that 90% of the extra heat stored by the planet over the past 50 years is found in the ocean, these measurements provide the best thermometer we have to track Earth’s warming.

Little buoy lost

We deployed the float to measure how much ocean heat was reaching the rapidly changing Totten Glacier, which holds a volume of ice equivalent to 3.5 metres of global sea-level rise. Our previous work had shown enough warm water was reaching the base of the ice shelf to drive the rapid melting.

To our disappointment, the float soon drifted away from Totten. But it reappeared near another ice shelf also currently losing ice mass and potentially at risk of melting further: the Denman Glacier. This holds ice equivalent to 1.5m of global sea-level rise.

The configuration of the Denman Glacier means it could be potentially unstable. But its vulnerability was difficult to assess because few ocean measurements had been made. The data from the float showed that, like Totten Glacier, warm water could reach the cavity beneath the Denman ice shelf.

Our float then disappeared under ice and we feared the worst. But nine months later it surfaced again, having spent that time drifting in the freezing ocean beneath the Denman and Shackleton ice shelves. And it had collected data from places never measured before.

Why measure under ice?

As glaciers flow from the Antarctic continent to the sea, they start to float and form ice shelves. These shelves act like buttresses, resisting the flow of ice from Antarctica to the ocean. But if the giant ice shelves weaken or collapse, more grounded ice flows into the ocean. This causes sea level to rise.

What controls the fate of the Antarctic ice sheet – and therefore the rate of sea-level rise – is how much ocean heat reaches the base of the floating ice shelves. But the processes that cause melting in ice-shelf cavities are very challenging to observe.

Ice shelves can be hundreds or thousands of metres thick. We can drill a hole through the ice and lower oceanographic sensors. But this is expensive and rarely done, so few measurements have been made in ice-shelf cavities.

What the float found

During its nine-month drift beneath the ice shelves, the float collected profiles of temperature and salinity from the seafloor to the base of the shelf every five days. This is the first line of oceanographic measurements beneath an ice shelf in East Antarctica.

There was only one problem: because the float was unable to surface and communicate with the satellite for a GPS fix, we didn’t know where the measurements were made. However, it returned data that provided an important clue. Each time it bumped its head on the ice, we got a measurement of the depth of the ice shelf base. We could compare the float data to satellite measurements to work out the likely path of the float beneath the ice.

These measurements showed the Shackleton ice shelf (the most northerly in East Antarctica) is, for now, not exposed to warm water capable of melting it from below, and therefore less vulnerable.

However, the Denman Glacier is exposed to warm water flowing in beneath the ice shelf and causing the ice to melt. The float showed the Denman is delicately poised: a small increase in the thickness of the layer of warm water would cause even greater melting.

What does this mean?

These new observations confirm the two most significant glaciers (Denman and Totten) draining ice from this part of East Antarctica are both vulnerable to melt caused by warm water reaching the base of the ice shelves.

Between them, these two glaciers hold a huge volume of ice, equivalent to five metres of global sea level rise. The West Antarctic ice sheet is at greater risk of imminent melting, but East Antarctica holds a much larger volume of ice. This means the loss of ice from East Antarctica is crucial to estimating sea level rise.

Both the Denman and Totten glaciers are stabilised in their present position by the slope of the bedrock on which they sit. But if the ice retreated further, they would be in an unstable configuration where further melt was irreversible. Once this process of unstable retreat begins, we are committed. It may take centuries for the full sea-level rise to be realised, but there’s no going back.

In the future, we need an array of floats spanning the entire Antarctic continental shelf to transform our understanding of how ice shelves react to changes in the ocean. This would give us greater certainty in estimating future sea-level rise.

Steve Rintoul, CSIRO Fellow, CSIRO; Esmee van Wijk, Vanwijk, CSIRO; Laura Herraiz Borreguero, Physical oceanographer, CSIRO, and Madelaine Gamble Rosevear, Postdoctoral Fellow in Physical Oceanography, University of Tasmania

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

When we think of coral reefs, we picture bright fish, clear water and colourful corals. But reefs have also shaped the planet in deeper ways.

Our new study, published in Proceedings of the National Academy of Sciences, shows reefs have helped regulate Earth’s climate and life for more than 250 million years.

They link geology, chemistry and biology into one grand planetary feedback loop. And their rise and fall over hundreds of millions of years set the pace of recovery from past carbon dioxide shocks, holding vital lessons for today.

From hot to cold

Earth’s climate has swung between hot and cold periods over its long history.

These shifts reflect how carbon dioxide enters and leaves the atmosphere – since more carbon in the air means higher temperatures. Much of this happens through chemical reactions on land and the burial of carbonate minerals in the ocean.

A key part of this balance is ocean alkalinity. This describes the ocean’s ability to neutralise acids and absorb carbon dioxide.

To investigate how reefs have influenced this process, we used reconstructions of ancient geography, river systems and climate, and then ran computer models back to the Triassic Period – about 250-200 million years ago. This was when the first dinosaurs appeared.

These tools revealed that reefs influenced how fast Earth recovered from large releases of carbon dioxide.

Two major modes

We found Earth switches between two major modes depending on the state of corals reefs.

The first mode occurs when tropical shelves (shallow, submerged continental areas in tropical latitudes) are broad and reefs thrive. This causes calcium carbonate – the chemical compound that builds corals – to accumulate in shallow seas. Calcium makes water more alkaline, so when it’s locked up in coral the ocean becomes less alkaline.

With less alkalinity, the ocean loses some of its ability to soak up carbon dioxide. As a result, when carbon levels increase due to things like volcanic eruptions, the atmosphere can take hundreds of thousands of years to recover.

The second state happens when climate shifts, sea level falls, or tectonics restrict shallow habitats, and reefs shrink or disappear. Calcium then builds up in the deep ocean, making it more alkaline.

This means the ocean can absorb carbon dioxide more quickly.

A shift in recovery time

Depending on which mode it’s in, Earth will respond very differently to the same increase in atmospheric carbon levels.

In phases when reefs dominate, recovery slows because shallow seas trap the dissolved minerals, known as ions, that would help the ocean absorb carbon.

In phases when reefs collapse, recovery speeds up because the ocean’s buffering system is stronger and it is better able to absorb carbon dioxide.

These alternating periods have operated for more than 250 million years. They shaped climate rhythms and influenced how marine life evolved.

The plankton connection

That’s not all that happens when reefs collapse.

When calcium and carbonate ions shift from coastal seas to the open ocean, nutrients follow. This fuels plankton growth.

These tiny algae absorb carbon from near the surface and take it to the bottom the ocean when they die, where it is trapped in deep-sea sediment.

The fossil record shows more new kinds of plankton evolved in periods when reefs collapsed. In contrast, in phases when reefs dominated, evolutionary change was slower because there were less nutrients for plankton in the open ocean.

In essence, the rise and fall of reefs helped set the tempo of ocean biological evolution. And this biological impact made the reefs’ impact on the carbon cycle and global climate even more pronounced.

A message from the deep past

Today, humanity is adding carbon dioxide to the atmosphere at a rate comparable to some of the greatest carbon disruptions in Earth’s history. At the same time, coral reefs are declining due to warming, acidification and pollution.

If the current reef loss mirrors ancient reef-collapse events, calcium and carbonates may again shift to the deep ocean. In theory, it could strengthen the absorption of carbon dioxide over the long term. But this would come only after catastrophic ecological loss.

The key lesson is that Earth will recover – but not on human timescales. Geological recovery takes thousands to hundreds of thousands of years.

Tristan Salles, Associate Professor, School of Geosciences, University of Sydney and Laurent Husson, Earth sciences researcher, Centre national de la recherche scientifique (CNRS)

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

You might know Australia’s dietary guidelines from the famous infographics showing the types and quantities of foods we should eat to have a healthy diet.

Last updated 12 years ago, the National Health and Medical Research Council is now revising them to consider not only how food affects our health but also how sustainable our foods are. At least 37 other countries have already added sustainability to their dietary guidelines.

Many countries use global load indicators to assess the environmental impact of specific foods, based on the planetary boundaries within which humanity can safely operate. While useful to compare between countries, these indicators don’t match Australia’s environmental risks and priorities.

Unlike many other countries, locally produced food represents around 90% of what Australians eat. The environmental footprint of these foods is shaped almost entirely by the country’s unique landscapes, climates and farming systems.

Our recent research suggests forthcoming guidelines need to take local conditions into account. If global load indicators are the sole way to measure impact, the guidelines won’t capture Australia’s specific environmental challenges in producing food.

Local indicators matter

Global load indicators include greenhouse gas emissions, how much land is used per kilo of food, water use, land and water pollution and biodiversity loss.

This is how we get common figures such as the statistic that it takes 1,670 litres of water to produce 1 kilogram of rice.

While global measures are useful in comparing between countries and products, they don’t always match local environmental risks and priorities.

For example, using 1,670L of water to produce a kilo of rice in the contested and controlled Murray Darling Basin will have a different impact compared to using the same volume in Western Australia’s Kununurra irrigation system, where water is more abundant and has fewer alternative uses. Growing a kilo of rice in Italy will differ again.

If we want dietary guidelines to encourage real improvements on farm and in rural landscapes, environmental indicators must reflect the challenges rural stakeholders actually face.

Consumer preferences have already shifted several food production systems. Rising demand for free-range eggs and grass-fed beef has changed how farmers operate. It’s important to get this right.

One size does not fit all

Australia’s agricultural lands are diverse.

By area, more than 80% of our farmland falls in the rangelands. Here, cattle and sheep graze with minimal human intervention on vast tropical savannas, woodlands, shrublands and grasslands. Low rainfall and poor soils mean livestock are kept at low densities. Other food production options haven’t proved viable.

If we used global load indicators, food from rangelands would be assessed as having a high environmental impact due to large land use, lots of potentially polluting nutrients (dung and urine) and use of rainfall to grow forage vegetation.

But the main environmental issues for Australia’s rangelands are different, including methane emissions from livestock, land degradation, invasive weeds such as buffel grass and biodiversity loss.

Australia’s next largest area of agriculture is mixed crop and livestock, found in regions such as the Mallee in Victoria and Western Australia’s Wheatbelt. Most crops and 40% of livestock are produced in these areas, characterised by reliable rainfall patterns and low to medium rainfall of around 250–450 millimetres a year.

Farming here can make soils more acid due to high levels of nitrogen from fertilisers, alongside issues such as dryland salinity, erosion, biodiversity loss and greenhouse gas emissions. These issues have degraded some land so much it can’t sustain farming.

For these two types of agriculture, local indicators work better.

By contrast, the intensive and productive irrigated farms of the Murray–Darling Basin have environmental impacts more aligned to global indicators. Environmental issues here include greenhouse gases, competition for land and water use, nutrient pollution (primarily fertilisers) and biodiversity loss.

Good for your health – and the environment?

While previous Australian studies have assessed the environmental footprint of different foods or focused on a narrow description of environmental impact derived from overseas studies, these haven’t accounted for local environmental priorities or trade-offs.

Trade-offs are common. For instance, plant-based diets may result in lower greenhouse gas emissions but can increase pressure on soil health and biodiversity, as crops are commonly grown as monocultures with high fertiliser and pesticide use.

Common Australian diets mixing plant and animal foods can have a lower impact on biodiversity and soil health but higher greenhouse gas emissions, as mixed diets entail a more diverse range of cultivated plants and animals but rely more on methane-producing livestock.

Recognising and balancing these trade-offs will be essential if Australia’s updated dietary guidelines are to support healthy people and a healthy environment.

What’s next?

Ideally, Australia’s updated dietary guidelines will capture the unique pressures and challenges of producing food locally. This won’t be easy, given impacts will vary across different foods, regions and production systems. But the tools are already available.

Farm software can track every aspect of the production in a local environmental context, making it possible to predict impacts on the natural capital of individual farms – if agreements to share and aggregate data can be negotiated.

Gathering these data will allow local environmental indicators to be embedded in dietary guidelines. If this is done, it will become possible to link recommended diets to sustainability reporting. Farms, retailers and banks are increasingly required to report sustainability metrics, which can be linked to foods.

That means Australians could see the environmental credentials of their food on the labels, based not on global averages – but on how the specific farm is doing.

David Masters, Adjunct Professor in Agriculture and Environment, The University of Western Australia; David Lemon, Research Group Leader: Environmental Informatics, CSIRO; Dianne Mayberry, Principal Research Scientist, Agriculture, CSIRO, and Sonja Dominik, Research Scientist, Animal Breeding and Genetics, CSIRO

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

Every year, government workers around Australia start fires in the bush. The idea behind these prescribed burning programs is that removing dry leaves and branches reduces the chance of bigger, more dangerous fires. Over many decades, prescribed burning has settled into a dogma – an unquestionable good.

This line of thinking dates back to the 1939 Stretton Royal Commission, which followed the catastrophic Black Friday fires. To avoid future devastation, Judge Leonard Stretton called for large-scale prescribed burning to reduce fire fuel.

But Stretton’s crucial main judgement is often omitted from the story. In his judgement, Stretton singled out burning forests to promote pasture as a root cause of Black Friday:

the fire stimulated grass growth; but it encouraged scrub growth far more. Thus was begun the cycle of destruction which cannot be arrested in our day.

If shrubby regrowth is the real problem, why did Stretton call for more prescribed burning? His reasoning: it was too late to change course. Any forest “in a dangerous condition” of dense regrowth had to be cleared or burned.

As our new research on southwestern Australia’s karri and jarrah forests shows, Stretton’s lesser-known comments might hold a solution: burn far less to stop fire-prone regrowth making the next fires worse.

Of bushfire and scrub

For millennia, Australia’s First Nations burned small areas with extraordinary control and precision, sometimes leaving vast landscapes deliberately unburnt. This regime produced a low fire risk landscape of old, open forest, interspersed with a mosaic of areas burnt very frequently.

In comparison, British colonisers used large-scale fires to clear leaf litter and promote pasture for cattle and sheep.

For instance, after years of setting fires along the lower Snowy River, the seasoned bushman K.C Rogers described how the original forests had been converted into “almost impenetrable peppermint scrubs”.

As an unnamed Gundungurra elder once told journalist Dame Mary Gilmore:

[settlers] lit them and let them run like a child that loved destruction.

In his testimony to the 1939 Royal Commission, the Commonwealth Inspector-General of Forests, Charles Lane Poole, said:

the thickening up of our forests is entirely due to fire and the exclusion of fire will render them less susceptible to fire

What Rogers describes as “scrubs” and Lane Poole as “thickening” are the same thing: dense regrowth of fire-prone shrubs after fire.

Plants can calm a fire or feed it. Vegetation near the ground can easily ignite and even carry fire into the canopy, but vegetation high above the ground works to slow the winds fanning the flames. Burning or logging mature forests can lead to decades of higher fire risk.

Short term gain, long-term pain?

Prescribed burning resets the clock, giving a few short years with an open understorey. But the void is soon filled by flammable fast-growing shrubs.

A dry, dense understorey makes bushfires more severe. The single strongest predictor of forest flammability is the height and density of the shrubby understorey.

The alternative is to stop burning and wait for long-term openness to return naturally, as Lane-Poole suggested. As forests age, taller plants able to calm a fire take light, water and nutrients, outcompeting shorter plants which feed fire. But Stretton judged this too risky, as forests left to recover naturally would “always remain dangerously inflammable”.

Official fire records show recovery time can vary from 21 years in ash forests in the Australian Alps, to 56 years in southwest karri and jarrah forests, to nearly a century in the fire-sensitive Great Western Woodlands running from the Nullarbor to the WA Wheatbelt.

Burning the southwest

Since the 1960s, the WA Department of Biodiversity, Conservation and Attractions (DBCA) has used prescribed burns to reduce fuel load in southwestern forests.

“Fuel load” is a concept invented in the United States to describe layers of pine needles on pine forest floors. Our work shows it’s a poor fit for the Australian bush.

Burning off leaf litter in jarrah and karri forests clears the understorey for perhaps a year. Regrowing shrubs then create a dense understorey for about 50 years before opening up again.

In the southwest, large bushfires almost exclusively occur in forests thick with flammable regrowth. Around Sydney and the Blue Mountains, extreme fires are most common in recently burnt areas.

Challenging the norm

In 2022, the key research underpinning the WA conservation department’s burning regime was debunked.

The same year we published findings showing bushfires were occurring in dense shrubby regrowth. Scientists from the state conservation department responded, saying the department’s records contained flawed data and suggested ignoring all the records for old forests, which showed a decline in flammability over time.

But 98.4% of those old forest records were sound, according to their criteria. When we removed only the flawed ones, our findings became stronger.

We also used advanced modelling to understand how fire risk falls in mature forests: over time, low, dry shrubs are replaced by with taller, less-fire prone plants and trees.

Less fire – in a hotter world?

Would it be worth removing the short-term defence of prescribed burning to bring forests back to a less flammable state?

In our new study, we examined whether phasing out prescribed burning could help Australian forests endure climate change. The answer was clear: it’s entirely possible to stop the cycle of fire feeding more fire, and help forests endure new climatic conditions.

Official records show 77% of all areas burned in over 500,000 hectares of forested southwest national parks this century were due to prescribed burns. Of the remaining burned area, 20% burned from escaped prescribed burns and 23% from backburning done under a key efficiency indicator creating incentives for low cost backburns over direct firefighting. American studies show shifting from direct firefighting to backburning can triple the area burnt annually.

If large-scale prescribed burning and incentives to backburn ended, the area burned annually would immediately fall 87%, leaving only fires started by lightning, accident or arson.

But would fuel accumulate and drive uncontrollable fires? In our new research, we tested this common assumption using previously measured historic trends for the area as a whole and found southwest forests easily passed through the most flammable stages and matured into low-fire environments.

Our modelling suggests less area would be burned in the hotter, drier climate of 2100 than it is today if both widespread burning policies were ended.

What should authorities do?

When Stretton called for more prescribed burns, it was to reduce the risk of new conflagrations. But the megafires have continued. The Black Summer fires of 2019–20 were Australia’s worst to date. They happened despite record prescribed burning in national parks in New South Wales.

Humans have a deep-seated desire to intervene in nature. But our research shows long-unburnt forests act to limit fire without human intervention – even as the climate changes.

Moving away from routine burns doesn’t mean being idle. Authorities need to heavily invest in rapid fire detection and attack, better resourcing firefighters, training and employing many more specialist remote area firefighters and exploring fire-fighting drones.

It’s important to note our research focuses on southwestern forests. Many other Australian forests types also become more flammable through burning. But we haven’t yet crunched the numbers to see if it’s possible to age these forests through the shrubby, fire-prone intermediate phase.

Even so, what we’ve found so far is good news. Terrifying bushfires could become smaller and more manageable – if we overcome the drive to burn the bush.

In a response, a WA DBCA spokesperson said:

Prescribed burning is the State’s main risk mitigation strategy for protecting the community and environment from the devastating impacts of large bushfires. Lower fuel loads result in lower intensity and slower spreading bushfires in summer conditions.

[DBCA] research confirms that prescribed burning is effective in reducing the frequency, severity and size of bushfires in south west forests when at least 45 per cent of the landscape has a fuel age of less than six years since last burnt.

Removing fire from fire-prone ecosystems often leads to high severity fires, as seen in a range of significant bushfires that have occurred in Australia and overseas. Claims that forest flammability declines with age rest on data that remain inadequate. Following these recommendations would be unwise as it would likely lead to substantially increased bushfire risk and impact for many decades.

Philip Zylstra, Research Associate, University of New South Wales, and Adjunct Associate Professor, Curtin University and David Lindenmayer, Distinguished Professor of Ecology, Fenner School of Environment and Society, Australian National University

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

More than 900 people are dead, thousands more missing and millions affected by a band of cyclones and extreme monsoonal weather across southern Asia. Torrential rain has triggered the worst flooding in decades, accompanied by landslides. Indonesia, Sri Lanka, Thailand, Vietnam and Malaysia have been hit hardest. The death toll is likely to rise significantly.

Normally, cyclones don’t form close to the equator. But Cyclone Senyar formed just north of the equator in the Malacca Strait. It triggered lethal flooding in Sumatra and peninsular Malaysia last week.

It wasn’t alone. Other tropical cyclones formed along a zone of converging trade winds north of the equator. Typhoon Koto caused severe flash floods and landslides in the Philippines before weakening as it neared Vietnam. Tropical Cyclone Ditwah devastated Sri Lanka. One reason Sumatra was hit by such severe flooding was due to the unusual interaction between Typhoon Koto and Cyclone Senyar, which has now weakened.

The near-simultaneous emergence of these intense storms isn’t unheard of, and equatorial cyclones are rare but known. But the devastation is extraordinary. Sri Lankan President Anura Kumara Dissanayake described the floods as the “most challenging natural disaster” in the country’s history. Is there a climate link? We don’t know yet, but we do know climate change is projected to trigger fewer cyclones overall, but with higher intensity.

Why are cyclones rare near the equator?

Cyclones, typhoons and hurricanes are different names for the same strong, spinning tropical storms. These storms form over large expanses of warm water – but not usually on the equatorial seas.

This is because there’s not enough Coriolis force from Earth’s rotation at the equator to spin storms into their classic cyclonic structure.

The closest cyclone to the equator was the 2001 Tropical Storm Vamei which formed at just 1.4°N. Cyclone Senyar formed at 3.8°N.

While tropical cyclones can form in any month, they’re more common between July and October in the northwest Pacific and North Indian oceans. Cyclone Senyar and Typhoon Koto formed in the Northwest Pacific Basin, which has the largest, most frequent and most intense tropical cyclones in the world. Several devastating typhoons have hit the Philippines and parts of southern China this year.

One reason these cyclones have caused widespread damage is because they have hit countries where cyclones are rare, such as Indonesia and Malaysia.

Tropical cyclones are often smaller and much less common in the North Indian Ocean, including the Bay of Bengal and Arabian Sea. But Cyclone Ditwar tracked directly down Sri Lanka’s east coast, magnifying the damage.

Is there a climate link?

As the world’s oceans and atmosphere warm at an accelerating rate due to the rise in greenhouse gases from burning fossil fuels, tropical cyclones are expected to become more intense.

This is because cyclones get their energy from warm oceans. The warmer the ocean, the more fuel for the storm.

The warming atmosphere is supercharging the global water cycle, and peak rainfall rates are increasing. When more rain falls in a short time, flash flooding becomes more likely.

We can’t immediately say climate change made these storms worse, as it takes time to pinpoint any link.

What does this mean for Australia’s cyclone season?

Many Australians will wonder whether these devastating cyclones across Asia are a warning for northern Australia’s monsoon season.

The wet season has started with a bang in northern Australia, after Severe Tropical Cyclone Fina caused damage and disruption across the Top End and Kimberley last week. It was very early for a cyclone in the south Pacific and Indian oceans, as the season runs November to May.

Last week also saw the most damaging spring storms in more than a decade in southeast Queensland and northern New South Wales. Giant hail and destructive winds did major damage, costing one insurer an estimated A$350 million.

This doesn’t mean a bad cyclone season is guaranteed. It’s not possible to predict individual tropical cyclone events far in advance.

All indicators point to a mixed wet season across the north this year, with below-average rainfall across much of the northwest and average to above-average rainfall across the northeast.

Australia’s Bureau of Meteorology has just declared a La Niña in the Pacific. La Niña typically bring cooler, wetter weather to northern Australia and a stronger monsoon and higher risk of cyclones. This La Niña is likely to be relatively weak and short-lived, which is why rainfall predictions are largely average.

Across most of the Coral Sea, sea surface temperatures are up to 2°C above normal. This unusual warmth increases the risk of cyclone formation as well as more intense monsoonal rains and flooding in coming months.

In the south, there’s increased risk of heatwaves and bushfires, with a very hot summer forecast across most of Australia.

The Bureau of Meteorology recently ended seasonal cyclone forecasts as it’s no longer possible to do so reliably. Until now, meteorologists have used historic data to reasonably accurately model the total number of cyclones in a season. But the climate is now changing so fast it’s no longer possible to do this. As rescue attempts continue in many countries in the region, it’s clear we are now entering uncharted territory.

Steve Turton, Adjunct Professor of Environmental Geography, CQUniversity Australia

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

If you were to wander along the parts of Antarctica that are ice-free, you might be surprised to see something soft and luxurious growing right at your feet: deep green carpets of moss that look like draped green velvet nestled between rocks.

These moss beds, often called the “Daintree of Antarctica”, are like miniature forests.

From above, these velvet-like carpets rise and fall in gentle curves, forming a brain-like structure of miniature ridges and valleys. Up close, countless tiny shoots packed tightly together make the moss appear plush, with tiny green leaves catching the light.

What you can’t see – but might be able to feel – are the huge variations in temperature in these moss beds. In fact, as new research I led, published in Global Ecology and Biogeography, shows, one small patch of moss in Antarctica can create as much temperature variation as an entire mountain range elsewhere on the planet.

This discovery reveals how small-scale terrain shapes life in extreme environments – and why Antarctic heatwaves could threaten these fragile ecosystems.

Long-term declines

Field observations have shown that moss beds in East Antarctica are changing.

Long-term declines in moss health closely follow the spatial structure of the miniature ridges and valleys within the moss beds – or, in technical terms, the “micro-topography”.

Mosses living in the valleys have remained consistently healthy. This is shown by their vibrant green colour. However, mosses growing on ridges are more likely to become stressed and eventually die.

Our new research offers an explanation for why this is happening.

Measuring and modelling mosses

Over three research expeditions, colleagues and I spent time camping on a remote island in the Maritime Antarctic region below South America, and stayed at Australia’s Casey Station in East Antarctica, approximately 3,800 kilometres south of Perth.

Both regions, on opposite sides of Antarctica, have experienced different climatic changes in recent decades. The former has warmed, while the latter has become windier and drier.

However, both regions host expansive and ecologically significant moss beds.

To understand what’s driving biological patterns at the moss micro-scale, we placed a series of tiny sensors at different positions throughout the moss beds. We also collected imagery to generate high resolution digital models of the moss surface.

Specific features of the moss surface were derived from the models, such as vertical elevation, slope angles and direction angles. These features were used in mathematical models of solar radiation, telling us how much light the moss surface receives each day and how this differs based on a moss’s position within the moss bed.

From a moss bed to a mountain range

We found that Antarctic mosses create their own miniature climates, and these can vary dramatically in a single square metre.

Mosses living just centimetres apart can differ by 15°C in their daily maximum temperatures and by more than 2°C in their average temperatures over the growing season.

Some micro-scale positions in the moss bed heat rapidly in sunlight, reaching nearly 30°C despite freezing air temperatures, while neighbouring patches may never rise above 10°C.

To illustrate how extreme this is, we compared these moss-scale differences to land surface temperatures from mountainous regions worldwide. The temperature range within a single square-metre moss patch was equivalent to the change you’d experience by climbing one to two kilometres up a mountain.

In other words: a moss bed the size of a coffee table can contain as much thermal variation as an entire mountain range.

These differences are caused by a range of factors, including complex interactions between moss micro-topography and seasonal shifts in the sun’s elevation angle. In some locations in the moss beds, heat released from surrounding mosses can be trapped, which adds to the warming.

Tiny ridges were the warmest places for mosses to live in January. But these became the coldest in February as lower solar angles favoured steep slopes between ridges and valleys.

Ridges also experienced the most dramatic daily swings, with heating well above air temperature followed by rapid freezing – conditions that are stressful for plants. In contrast, mosses in small, sheltered valleys remained shaded. But these consistently had the warmest and most stable temperatures, showing that trapped heat released by surrounding mosses can outweigh direct sunlight.

Mosses are reaching their limit

Understanding this fine-scale complexity is crucial for predicting how Antarctic mosses will respond to climate change and the growing risk of heatwaves.

This matters most for mosses living at the cold limits of life, as temperature controls when they can photosynthesise and grow. Mosses must warm up to stay active in freezing conditions, but they also begin to experience physiological stress above about 30°C.

We found that mosses in the warmest micro-habitats are already approaching this threshold. The same warming ability that helps them survive the cold may soon become a liability under increased warming and heatwave events, where air temperatures up to 18°C in Maritime Antarctica and 9°C in East Antarctica have already occurred.

In a landscape dominated by ice, Antarctica’s moss beds remind us that life persists through subtle strategies. But our work shows that plants living in coldest places on Earth could be approaching their heat limits.

As Antarctic heatwaves become more common, the strategies that once benefited them could instead push them beyond their limits, and a mosses position within the moss bed will likely influence how these events impact them.

Krystal Randall, Postdoctoral Research Fellow, School of Earth, Atmospheric and Life Sciences, University of Wollongong

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

Across Britain, ponds are quietly vanishing. Pouring over historic maps from the 1900s to trace old pond sites, I was struck by how many once dotted the landscape. Today, more than half have disappeared, a loss that threatens wildlife and our ability to cope with a changing climate.

That may be surprising as ponds seem small and insignificant. We talk about rivers, reservoirs and wetlands but ponds get very little mention, yet they punch far above their weight in ecological value. They store water, support biodiversity and help buffer floods and droughts. Losing them undermines both nature and our ability to adapt to climate extremes.

Restoring ponds – old and new, rural and urban – is one of the simplest, most effective steps we can take. Every pond counts, from a farm hollow to a garden bowl. Together, they form networks that wildlife needs to survive and make our landscapes more resilient to climate change.

The takeaway? Ponds do far more than look good. They link habitats, boost biodiversity and strengthen climate resilience. Restoring them is a practical, low-cost solution that begins with something as basic as adding water.

For wildlife, ponds are vital ecosystems and support far more than aquatic species. They provide water, food and habitat for pollinating insects, birds, bats and other mammals. Crucially, amphibians such as frogs and newts rely on networks of ponds close enough for them to move between. Lose that network or “pondscape”, and species vanish.

The consequences extend beyond biodiversity. Ponds act as natural buffers against climate extremes. Ponds act like natural sponges. During heavy rain, they slow water running across the ground and store this to reduce flood peaks. In periods of drought, they store water for plants and animals when streams run dry. They can also lock away carbon and filter pollutants, improving water quality.

Urban ponds in parks, school grounds and people’s gardens can provide vital biodiversity hotspots and local cooling during heatwaves. They help manage stormwater when we have heavy rains, reducing pressure on drains. And they can help connect people with nature, something proven to boost wellbeing.

Historic maps reveal a dense network of ponds that once dotted the landscape, but more than half of Britain’s ponds have disappeared since 1900. Research that I was involved in found that 58% of ponds present in 1900 were lost by 2019 in the Severn Vale region of the UK, and this went hand in hand with a decline in pond density with a 25m increase in the average distance between contemporary ponds.

The decline in ponds can be seen worldwide, driven by changes in agriculture and the growth in urban areas. As agriculture has intensified, these small waterbodies were seen as obstacles to efficiency. Farmers filled them in to create larger, machine-friendly fields, while improved drainage systems and water abstraction dried out many more. Expanding urban areas also replaced ponds with roads, housing and hard surfaces.

Bringing ponds back to life

Restoring ponds is one of the simplest, most effective ways to boost biodiversity and climate resilience. Whether it’s reviving forgotten waterbodies or creating new ones, these small habitats deliver big benefits for wildlife and communities.

The first step is knowing where ponds are and where they’re missing. Mapping today’s ponds shows the gaps, helping us plan new ones to link habitats and build a healthy pond network. Historic maps reveal lost ponds that can potentially be restored. Many ponds survive as “ghosts”.

Digging them out and restoring these is surprisingly effective. Seeds buried for decades can germinate once water returns, reviving plants thought extinct locally. In Norfolk, farmers and conservationists have restored dozens of ghost ponds, and within months they teem with life .

However, you don’t need a big conservation project to make a difference. Start small. A garden pond, even the size of a washing-up bowl, can attract frogs, insects and birds. Community groups can work with councils to revive neglected ponds in parks, public gardens or village greens. If you’ve got a garden, or even a wheelbarrow or large pot, you can help rebuild the pond network.

The Royal Horticultural Society, the UK gardening charity, has great guidance on how to create a successful wildlife pond. Every pond counts and together they create the networks wildlife needs to survive and provide vital water storage.

Britain’s ponds are disappearing fast, but every new or restored pond helps reverse that trend. Restoring old ponds and creating new ones, even in gardens and parks, is one of the simplest, most effective steps we can take to protect wildlife and adapt to climate extremes.

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Lucy Clarke, Senior Lecturer, Department of Animal, Rural and Environmental Sciences, Nottingham Trent University

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When I, Erik Meijaard, worked as a wildlife consultant for a timber concession in Borneo, I often chatted with the logging truck drivers — and quickly realised that some of them knew far more about local wildlife populations than the company’s own biodiversity teams.

“If you want to see clouded leopards, ride with me in my truck — I can almost guarantee we’ll spot one or two near kilometre 38 around two in the morning,” one of the drivers told me at the time.

I didn’t spot the elusive cats that night, but two years later, early one morning, I finally found one sitting calmly beside a logging road. The driver had been right all along: these leopards really do like the roads.

Since then, I have relied heavily on community-sourced information to monitor wildlife populations within company concessions and ensure that emerging threats are quickly detected and addressed.

I began by creating the first orangutan distribution maps in the 1990s through village interviews, later expanding the approach to 700 villages in 2008 to better understand local perceptions of forests and wildlife.

From 2019 to 2025, I ran an oil-palm-plantation–based citizen-science pilot that generated nearly 190,000 wildlife records from 4,000 workers.

These experiences show that some of the most valuable ecological knowledge rests with the people who live closest to the forest — not the scientists who visit only once a year.

How does citizen science work?

Building on that insight, Emily (who co-wrote this article with me) and I introduced a new version of the model for broader study in four villages in the Kapuas Hulu district of West Kalimantan. There, the local community manages the forest under a social forestry scheme.

We worked directly with them. Anyone with a smartphone can record wildlife sightings using our simple mobile app named Kehatiku (which in Indonesian means both “to my heart” and “my biodiversity”). Observations — from orangutan photos to gibbon audio clips — are then uploaded with GPS coordinates.

Each record then goes through a multi-stage verification process: an AI-assisted screen check for duplicate images and location mismatches, followed by review from our team of verifiers and species experts, who cross-reference field guides.

Once a record is verified, we issue a payment to the observer — ranging from around US$0.60 for a bird-call recording to about US$6 for a clear photo or video of a wild orangutan.

Since the citizen science program launched in 2023, 567 participants have recorded more than 58,000 wildlife observations from community forests — at roughly one-twentieth the cost of conventional surveys. The program creates both income and incentives to protect wildlife and their habitats.

What the data reveal?

So far, the data show unexpectedly high numbers of orangutans, gibbons, and many other species in these community forests, including several of global conservation concern.

The most frequently reported wildlife in the four Kapuas Hulu villages includes orangutans (with 9,766 nest records), white-rumped shamas, sun bear signs, long-tailed macaques, and stingless bees.

Direct sightings of Bornean orangutans and regular recordings of gibbon calls confirm that these species persist outside protected areas — even within agricultural landscapes bordering the villages.

This information is invaluable to understand how threatened mammals survive in mixed-use forests, where formal surveys are rare or expensive. We are currently doing critical testing as to whether the data are strong enough to generate statistically robust occupancy estimates — showing how wildlife species use village forest areas.

For plantations, we can already translate these findings into a living index, an important tool for developing data-driven conservation policies and interventions.

Shifting behaviour and social impact

In early 2025, we also collaborated with a local partner to conduct social baseline surveys to assess the program’s socioeconomic impact.

Initial survey results suggest a shift in perception is already underway. More than 70% of residents across the four pilot villages had heard of the initiative, and nearly two-thirds said they are interested in joining.

About a third already earn income from verified wildlife observations — typically US$30 to US$180 every three months, a meaningful supplement in communities where most households live on less than US$120 per month.

More importantly, attitudes toward wildlife are shifting. Where songbirds were once trapped and sold to traders, many villagers now choose to leave them in the forest — realising it’s more profitable to record the birds’ presence and get paid for it.

A model for inclusive, low-cost monitoring

Financial incentives have clearly boosted engagement. Observation rates rose from about 17 per village per month during the voluntary phase to more than 6,000 per month once payments were introduced.

At an average cost of just US$0.85 per observation, this approach is far cheaper than traditional transect or camera-trap surveys, which can cost US$300 per camera or more.

Not only does it reduce logistical costs, but relying on local observers also makes it possible to cover vast, remote areas.

And unlike short-term research projects, this one runs year-round — because the motivation, and the data, come from the community itself.

The programme also strengthens local governance. Regular meetings and WhatsApp groups allow residents to discuss verification results, propose rule changes, and collectively decide how to manage conflicts over shared rewards. We also close the information loop by translating wildlife observations into insights communities can use to guide their decisions.

These interactions, along with transparent payment records, are boosting accountability and participation in broader village decision-making. This transparency has helped build strong trust within the community.

On one occasion, when a participant submitted an internet-sourced photo as fake evidence, the peers insisted on removing them from the project — a proof that data integrity now matters at the community level.

Beyond data: Building ownership and pride

Beyond science, the project is fostering local ownership and pride in nature. For participants, the forest has become a living asset — one that generates income through conservation. That shift in perception may be the most important outcome of all.

With mobile networks and digital payment systems now widespread across Indonesia, this low-cost, scalable model could be expanded to thousands of villages. Citizen science can become a cornerstone of future wildlife conservation — and Indonesia could lead the way in making it happen.

From the truck drivers who spotted clouded leopards in the 1990s to today’s smartphone-armed villagers, the message is clear: science and stewardship thrive when everyone can take part — and be fairly rewarded for it.

Erik Meijaard, Honorary Professor of Conservation, University of Kent and Emily Meijaard, Head of Communications at Borneo Futures

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

On the western flanks of Mount Kenya lies the Laikipia plateau, an achingly beautiful landscape that is both a refuge for wildlife and a home to traditional Masai communities. Black rhinos, which were once nearly extinct, are now thriving on some of these conservation properties, thanks to the intense efforts to keep them safe.

The new documentary Rhino tells the story of the people and the challenges faced to protect wildlife in this volatile landscape. The cinematography and score beautifully captures the landscape, people, animals and pace of life, which is at times languorous and at times frantic.

The story unfolds from the perspective of two rangers. Ramson Kiluko is an experienced ranger who works with his team to watch, protect and understand the rhinos. The film gives us a glimpse into his family life, the camaraderie of the ranger team and the rich knowledge he has about the lives of individual rhinos and their landscape. Rita Kulamu is a young ranger learning about rhinos as her property prepares to welcome them. Their work takes place against a background of danger, posed by both people and animals.

Rhino focuses on the critical role rangers play in the conservation story of black rhinos, which is an inspiring change from the traditional wildlife documentary that suggests a wildness that exists without the need for human intervention or involvement. Once on the brink of extinction, it is precisely the intensive efforts made to protect rhinos by people like Kiluko and Kulamu that has seen numbers slowly rebound.

The film loosely follows a narrative around the planned move of 21 rhinos from the Lewa and Borana reserves in central Kenya, where they are too numerous, to Loisaba – a 58,000 acre wildlife conservation area which has long been without rhinos.

On Lewa and Borana, the rhinos fight for space and territory, on Loisaba they have the opportunity to create a new breeding population. Moving rhinos between reserves is a core part of their conservation. Poaching pressures require rhinos to be fiercely guarded. In Kenya, where my team has carried out research to understand the factors that lead to successfully breeding rhino populations, rangers are tasked with finding each rhino every day. Fences that keep rhinos in and people out mean that rhinos cannot move to avoid threats, avoid inbreeding, or to reestablish populations where they no longer are found.

Moving rhinos is far from easy. They can be aggressive and need to be handled with care. Rhinos are also not very resilient to being moved between properties. These moves often lead to rhinos dying from fighting, stress and disease.

The film shows how extreme drought led to a delay of several years to try to maximise the success of the move . This widespread and prolonged drought caused intense suffering of humans, livestock and wildlife. Conflicts over animals and land boiled over, leading to violence between communities but also towards rangers. These day-to-day challenges faced by conservationists are rarely touched on. Hopefully this film will help audiences understand that there are legions of passionate conservation professionals behind every success story.

However, there is much that the story doesn’t tell. My experience researching wildlife health and disease in this landscape has highlighted how critical it is to create solutions that benefit both nature and people. Laikipia is a complicated landscape, where land rights, land ownership and power inequalities create tensions, and even violence, between communities.

This is a landscape where settlers, European farmers that immigrated, appropriated the best, most productive beautiful lands from traditional communities. High-end conservation reserves manage landscapes that teem with wildlife but are often off limits to the people that once moved widely with their animals. Our conversations with local people suggest that they view rhino conservation as a Trojan horse, moved around to justify high fences, armed security and to restrict people’s movement.

Rhino portrays the situation in somewhat simplistic terms: the good rangers and the bad “bandits”. In reality, conservation sits at a much less clear cut interface between the haves and the have nots, between those with international and national support for protecting animals, and pastoralists, a traditional way of life where people move with their herds of animals across the land, who feel their rights and traditional lands have been taken from them and that the wild animals have more rights that they do.

Violence comes not just from evil, avaricious thieves, but sometimes from frustrated, desperate people who have to deal with too many animals on too little land. Rhino tells an interesting and valuable story, but true conservation success must also address inequality, disenfranchisement and the tensions that “parachute” and colonial conservation can create in local communities.

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Susanne Shultz, University Research Fellow, University of Manchester

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Fall marks the start of Iran’s rainy season, but large parts of the country have barely seen a drop as the nation faces one of its worst droughts in decades. Several key reservoirs are nearly dry, and Tehran, the nation’s capital, is facing an impending “Day Zero” – when the city runs out of water.

The situation is so dire, Iranian President Masoud Pezeshkian has revived a long-debated plan to move the capital from this metro area of 15 million people.

Previous administrations have floated the idea of moving the capital but never implemented it. Tehran’s unbridled expansion has created a host of problems, ranging from chronic water stress and land subsidence to gridlocked traffic and severe air pollution, while also heightening concerns about the city’s vulnerability to major seismic hazards.

This time, Pezeshkian has framed relocation as a mandate, not a choice. He warned in November 2025 that if nothing changes, the city could become uninhabitable.

How Iran got to the point of water bankruptcy

Drought has been a concern in this part of the world for millennia. A prayer by the Persian King Darius the Great that was carved in stone more than 2,000 years ago asked his god to protect the land from invaders, famine and lies.

However, today, Iran’s escalating water and environmental problems are the predictable outcome of decades of treating the region’s finite water resources as if they were limitless.

Iran has relied heavily on water-intensive irrigation to grow food in dry landscapes and subsidized water and energy use, resulting in overpumping from aquifers and falling groundwater supplies. The concentration of economic activity and employment in major urban centers, particularly Tehran, has also catalyzed massive migration, further straining already overstretched water resources.

Those and other forces have driven Iran toward “water bankruptcy” – the point where water demand permanently exceeds the supply and nature can’t keep up.

Iran’s centralized, top-down approach to water governance has proven ineffective in ensuring the sustainability of its water resources and in maintaining a balance between renewable water supply and demand, a gap that has continued to widen.

Since the 1979 revolution, Iran has pursued an aggressive hydraulic mission, building dams and diverting rivers to support sprawling cities and expanding irrigated agriculture. Driven by ideological ambitions, the country’s focus on food self-sufficiency together with international sanctions and economic isolation, have taken a heavy toll on the nation’s environment, particularly its water resources. Drying lakes, groundwater depletion and rising salinity are now prevalent across Iran, reflecting dire water security risks throughout the country.

As water resource and environmental engineers and scientists, including a former deputy head of Iran’s Department of Environment, we have followed the county’s water challenges for years. We see viable solutions to its chronic water problems, though none is simple.

Falling water reserves leave Iran vulnerable

Experts have been warning for years that the lack of foresight to tackle Iran’s water bankruptcy problem leaves the country increasingly vulnerable to extreme climate conditions.

Iranians are again seeing those risks in this latest drought.

Precipitation has been well below normal in four of the water years since 2020. That has contributed to a sharp decline in reservoir levels. Fall 2025 has been the hottest and driest fall on record for Tehran since 1979, testing the resilience of its water system.

The city faces mounting stress on already diminished groundwater reserves, with little relief in sight without significant rainfall.

Shrinking snowpack and shifting rainfall patterns make it harder to predict how much water will flow in rivers and when. Rising temperatures make the problem worse by boosting demand and leaving less water in the rivers.

There is no quick fix to resolve Tehran’s water emergency. In the near term, only significantly more rainfall and a reduction in consumption can offer respite.

Panicky moves to increase interbasin water transfers, such as the Taleqan‑to‑Tehran water transfer to pump water from the Taleqan Dam, over 100 miles (166 km) away, are not only inadequate, they risk worsening the water supply and demand imbalance in the long run. Iran has already experimented with piping water between basins, and those transfers have in many cases fueled unsustainable growth rather than real conservation, worsening water problems both in the donor and recipient basins.

At its core, Tehran’s predicament stems from a chronic mismatch between supply and demand, driven by rapid population growth.

Whether relocating the political capital, as suggested by Pezeshkian, could meaningfully reduce the city’s population, and hence the water demand, is highly doubtful.

The sparsely populated Makran region in the country’s southeast, along the Gulf of Oman, has been mentioned as a potential option, touted as a “lost paradise,” though details on how much of the city or population would move remain unclear.

Meanwhile, other major Iranian cities are facing similar water stresses, highlighting the fact that this is a nationwide threat.

Water solutions for a dry country

The country needs to start to decouple its economy from water consumption by investing in sectors that generate value and employment opportunities with minimal water use.

Agricultural water consumption can be reduced by producing higher-value, less water-intensive crops, taking into account food security, labor market and cultural considerations. Any water savings could be used to replenish groundwater.

Becoming more open to global trade and importing water-intensive crops, rather than growing them, would also allow Iran to use its limited agricultural land and water to grow a smaller set of strategic staple crops that are critical for national food security.

That’s a transition that will be possible only if the country moves toward a more diversified economy that allows for reduced pressure on the country’s finite resources, an option that seems unrealistic under economic and international isolation.

Urban water demand could be reduced by strengthening public education on conservation, restricting high-consuming uses such as filling private swimming pools, and upgrading distribution infrastructure to minimize leaks.

Treated wastewater could be further recycled for both drinking and nonpotable purposes, including maintaining river flows, which are currently not prioritized.

Where feasible, other solutions such as flood management for aquifer recharge, and inland groundwater desalination, can be explored to supplement supplies while minimizing environmental harm.

Taken together, these measures require bold, coordinated action rather than piecemeal responses.

Renewed talk of relocating the capital signals how environmental stresses are adding to the complex puzzle of Iran’s national security concerns. However, without addressing the root causes of the nation’s water bankruptcy, we believe moving the capital to ease water problems will be futile.

Ali Mirchi, Associate Professor of Water Resources Engineering, Oklahoma State University; Amir AghaKouchak, Professor of Civil & Environmental Engineering and Earth System Science, University of California, Irvine; Kaveh Madani, Director of the United Nations University Institute for Water, Environment and Health, United Nations University, and Mojtaba Sadegh, Associate Professor of Civil Engineering, Boise State University; United Nations University

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

The latest United Nations climate summit (COP30) was held between 10 and 21 November in Belém, Brazil. Although the event did not end with any significant progress towards the goals of mitigating global warming or advancing climate finance, it did leave us with one positive outcome: a group of countries has launched an initiative to phase out fossil fuels.

This summit was groundbreaking for two interrelated reasons. The first is that, in contrast to the three previous conferences, which were heavily policed, the streets of Belém were filled with protests. Thousands of demonstrators, including a large number of indigenous people, gathered to demand environmental justice, a term that refers not only to the consequences of climate change, but also to the need to protect territories and lives from the local impacts of oil extraction activities.

The second reason is that, for the first time, the need for a roadmap to abandon fossil fuels played a prominent role. Despite their key role in climate change, fossil fuels have been absent from COP decisions. Only the final agreement of COP28 in 2023 mentioned a vague intention to “transition away from fossil fuels”. This disappeared the following year at COP29, mainly due to pressure from Saudi Arabia.

But at COP30, more than 80 countries – led mainly by Colombia (itself an exporter of coal and oil) and Spain, and including most European Union countries – have called for a roadmap to phase out fossil fuels.

Oil producers resist climate action

The 2015 Paris Agreement led countries to adopt greenhouse gas emission reductions targets, or “nationally determined contributions” (NDCs). These measures are clearly insufficient to achieve their goal of mitigating climate change by limiting global warming to 1.5C.

States were also required to subsequently update their NDCs, but any revisions have either been very tentative or non-existent.

In 2024, the average temperature increase compared to pre-industrial times already exceeded 1.5C, and the latest United Nations report on the emissions gap indicates that, even if current national commitments were strictly met, the future increase would still be well over 2C.

Oil-producing countries, led by Saudi Arabia and Russia, fiercely opposed even mentioning the term “fossil fuels” in the COP30 final statement. In doing so they are not showing opposition to a particular type of climate policy, but rather blocking the one essential condition for the Paris Agreement’s goal to be met: a rapid and radical decrease in fossil fuel extraction.

Phasing out fossil fuels

Reducing fossil fuel supply will not be easy, and must be approached equitably. This means the areas at greatest environmental and social risk must be made a priority, local communities need to have a say, and financial compensation must be established where necessary.

One cannot simply expect national policies that affect demand for fossil fuels – such as the promotion of renewable energy or carbon pricing – to cause a corresponding reduction in the extraction and sale of fossil fuels. This outcome is by no means guaranteed, and such measures may even cause some governments and companies to accelerate the extraction of fossil resources in anticipation of worse times for business – the so-called “green paradox”.

Supply and demand are both key, and must be managed in the most multilateral way possible.

A COP of contrasts and contradictions

COP30 saw massive demonstrations by indigenous people, but there were also, as in previous COPs, huge numbers of lobbyists present. They not only represented the fossil fuel industry, but also the agricultural and livestock businesses that are destroying the Amazon.

The host country itself is a testament to these contradictions. Its president, Lula da Silva, made it a priority to create a fund against deforestation for tropical forests, but he has also approved new oil exploration by Brazil’s state-owned company Petrobras in the Amazon, ignoring cries from the country’s indigenous populations of “Our land is not for sale.”

This all occurred while Brazil’s Minister of the Environment, Marina Silva, urged all countries to have the courage to address the need to phase out fossil fuels.

No new climate finance

Climate financing involves payments from wealthy countries, who are historically responsible for global warming, to the poorest countries most affected by it. When talking about this, the official language of COPs has always avoided the term “climate justice”, and “reparations” even more so. However, there is talk of “differentiated responsibilities” and “equity”.

The Paris Agreement proposed mobilising around $100 billion annually for climate mitigation and adaptation. At COP29, a new collective financing target of $300 billion annually by 2035 was set. For comparison, this is less than 0.3% of global GDP and around 12% of global defence spending, which is growing year on year.

In this regard, nothing new has been proposed at COP30 beyond a reference to increasing dedicated adaptation funds. These amount to small promises and major failures to deliver, with no stipulations for how funds will be distributed. The funds themselves are a mixture of subsidies, loans and profitable private capital investments based on voluntary contributions. Additionally, it has not been made clear where the concept of a “developing country” ends.

Proposals to create specific sources of funding, such as a global wealth tax or levies on aviation or maritime transport emissions, were not considered.

A new conference on fossil fuels

Amidst tension between two fiercely divided sides, COP30 closed with a final declaration that makes no reference to fossil fuels and barely mentions deforestation. But what can be expected when decisions require absolute consensus, meaning that any individual country can veto their approval?

However, COP30’s most significant outcome was not this text, nor even the maintenance of the current COP framework. Outside the consensus – indeed, outside the UN itself – Colombia and the Netherlands have announced, with the support of many other countries, that they will draw up a roadmap for abandoning fossil fuels. They will begin by holding a conference of their own in April 2026.

Let us hope that this initiative opens up new perspectives, and that social movements continue to fight under the slogan they introduced many decades ago: “Keep fossil fuels in the ground”.

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Jordi Roca Jusmet, Catedrático de Economía, Universitat de Barcelona

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

When fire broke out at the world’s largest battery energy storage facility in January 2025, its thick smoke blanketed surrounding wetlands, farms and nearby communities on the central California coast.

Highways closed, residents evacuated and firefighters could do little but watch as debris and ash rained down. People living in the area reported headaches and respiratory problems, and some pets and livestock fell ill.

Two days later, officials announced that the air quality met federal safety standards. But the initial all-clear decision missed something important – heavy metal fallout on the ground.

When battery energy storage facilities burn, the makeup of the chemical fallout can be a mystery for surrounding communities. Yet, these batteries often contain metals that are toxic to humans and wildlife.

The smoke plume from the fire in Vistra’s battery energy storage facility at Moss Landing released not just hazardous gases such as hydrogen fluoride but also soot and charred fragments of burned batteries that landed for miles around.

I am a marine geologist who has been tracking soil changes in marshes adjacent to the Vistra facility for over a decade as part of a wetland-restoration project. In a new study published in the journal Scientific Reports, my colleagues and I were able to show through detailed before-and-after samples from the marshes what was in the battery fire’s debris and what happened to the heavy metals.

The batteries’ metal fragments, often too tiny to see with the naked eye, didn’t disappear. They continue to be remobilized in the environment today.

What’s inside the batteries

Moss Landing, at the edge of Monterey Bay, has long been shaped by industry – a mix of power generation and intensive agriculture on the edge of a delicate coastal ecosystem.

The Vistra battery storage facility rose on the site of an old Duke Energy and PG&E gas power plant, which was once filled with turbines and oil tanks. When Vistra announced it was converting the site into the world’s largest lithium-ion battery facility, the plan was hailed as a clean energy milestone. Phase 1 alone housed batteries with 300 megawatts of capacity, enough to power about 225,000 homes for four hours.

The energy in rechargeable batteries comes from the flow of electrons released by lithium atoms in the anode moving toward the cathode.

In the type of batteries at the Moss Landing facility, the cathode was rich in three metals: nickel, manganese and cobalt. These batteries are prized for their high energy density and relatively low cost, but they are also prone to thermal runaway.

Lab experiments have shown that burning batteries can eject metal particles like confetti.

Metals found in wetlands matched batteries

When my team and I returned to the marsh three days after the fire, ash and burned debris covered the ground. Weeks afterward, charred fragments still clung to the vegetation.

Our measurements with portable X-ray fluorescence showed sharp increases in nickel, manganese and cobalt compared with data from before the fire. As soon as we saw the numbers, we alerted officials in four counties about the risk.

We estimate that about 25 metric tons (55,000 pounds) of heavy metals were deposited across roughly half a square mile (1.2 square kilometers) of wetland around Elkorn Slough, and that was only part of the area that saw fallout.

To put this in perspective, the part of the Vistra battery facility that burned was hosting 300 megawatts of batteries, which equates to roughly 1,900 metric tons of cathode material. Estimates of the amount of batteries that burned range from 55% to 80%. Based on those estimates, roughly 1,000 to 1,400 metric tons of cathode material could have been carried into the smoke plume. What we found in the marsh represents about 2% of what may have been released.

We took samples at hundreds of locations and examined millimeter-thin soil slices with a scanning electron microscope. Those slices revealed metallic particles smaller than one-tenth the width of a human hair – small enough to travel long distances and lodge deep in the lungs.

The ratio of nickel to cobalt in these particles matched that of nickel, manganese and cobalt battery cathodes, clearly linking the contamination to the fire.

Over the following months, we found that surface concentrations of the metals dropped sharply after major rain and tidal events, but the metals did not disappear. They were remobilized. Some migrated to the main channel of the estuary and may have been flushed out into the ocean. Some of the metals that settled in the estuary could enter the food chain in this wildlife hot spot, often populated with sea otters, harbor seals, pelicans and herons.

Making battery storage safer as it expands

The fire at Moss Landing and its fallout hold lessons for other communities, first responders and the design of future lithium-ion battery systems, which are proliferating as utilities seek to balance renewable power and demand peaks.

When fires break out, emergency responders need to know what they’re dealing with. A California law passed after the fire helps address this by requiring strengthening containment and monitoring at large battery installations and meetings with local fire officials before new facilities open.

Newer lithium-ion batteries that use iron phosphate cathodes are also considered safer from fire risk. These are becoming more common for utility-scale energy storage than batteries with nickel, manganese and cobalt, though they store less energy.

How soil is tested is also important. At Moss Landing, some of the government’s sampling turned up low concentrations of the metals, likely because the samples came from broad, mixed layers that diluted the concentration of metals rather than the thin surface deposits where contaminants settled.

Continuing risks to marine life

Metals from the Moss Landing battery fire still linger in the region’s sediments and food webs.

These metals bioaccumulate, building up through the food chain: The metals in marsh soils can be taken up by worms and small invertebrates, which are eaten by fish, crabs or shorebirds, and eventually by top predators such as sea otters or harbor seals.

Our research group is now tracking the bioaccumulation in Elkhorn Slough’s shellfish, crabs and fish. Because uptake varies among species and seasons, the effect of the metals on ecosystems will take months or years to emerge.

Ivano W. Aiello, Professor of Marine Geology, San José State University

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

Around 56 million years ago, Earth suddenly got much hotter. Over about 5,000 years, the amount of carbon in the atmosphere drastically increased and global temperatures shot up by some 6°C.

As we show in new research published in Nature Communications, one consequence was that many of the world’s plants could no longer thrive. As a result, they soaked up less carbon from the atmosphere, which may have contributed to another interesting thing about this prehistoric planetary heatwave: it lasted more than 100,000 years.

Today Earth is warming around ten times faster than it did 56 million years ago, which may make it even harder for modern plants to adapt.

Rewinding 56 million years

Plants can help regulate the climate through a process known as carbon sequestration. This involves capturing carbon dioxide from the atmosphere via photosynthesis and storing it in their leaves, wood and roots.

However, abrupt global warming may temporarily impact this regulating function.

Investigating how Earth’s vegetation responded to the rapid global warming event around 56 million years ago – known formally as the Paleocene-Eocene Thermal Maximum (or PETM) – isn’t easy.

To do so, we developed a computer model simulating plant evolution, dispersal, and carbon cycling. We compared model outputs to fossil pollen and plant trait data from three sites to reconstruct vegetation changes such as height, leaf mass, and deciduousness across the warming event.

The three sites include: the Bighorn Basin in the United States, the North Sea and the Arctic Circle.

We focused our research on fossil pollen due to many unique properties.

First, pollen is produced in copious amounts. Second, it travels extensively via air and water currents. Third, it possesses a resilient structure that withstands decay, allowing for its excellent preservation in ancient geological formations.

A shift in vegetation

In the mid-latitude sites, including the Bighorn Basin – a deep and wide valley amidst the northern Rocky Mountains – evidence indicates vegetation had a reduced ability to regulate the climate.

Pollen data shows a shift to smaller plants such as palms and ferns. Leaf mass per area (a measure of leaf density and thickness) also increased as deciduous trees declined. Fossil soils indicate reduced soil organic carbon levels.

The data suggest smaller, drought-resistant plants including palms thrived in the landscape because they could keep pace with warming. They were, however, associated with a reduced capacity to store carbon in biomass and soils.

In contrast, the high-latitude Arctic site showed increased vegetation height and biomass following warming. The pollen data show replacement of conifer forests by broad-leaved swamp taxa and the persistence of some subtropical plants such as palms.

The model and data indicate high-latitude regions could adapt and even increase productivity (that is, capture and store carbon dioxide) under the warmer climate.

A glimpse into the future

The vegetation disruption during the PETM may have reduced terrestrial carbon sequestration for 70,000-100,000 years due to the reduced ability of vegetation and soils to capture and store carbon.

Our research suggests vegetation that is more able to regulate the climate took a long time to regrow, and this contributed to the length of the warming event.

Global warming of more than 4°C exceeded mid-latitude vegetation’s ability to adapt during the PETM. Human-made warming is occurring ten times faster, further limiting the time for adaptation.

What happened on Earth 56 million years ago highlights the need to understand biological systems’ capacity to keep pace with rapid climate changes and maintain efficient carbon sequestration.

Vera Korasidis, Lecturer in Environmental Geoscience, The University of Melbourne and Julian Rogger, Senior Research Associate, School of Geographical Sciences, University of Bristol

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

Deception is everywhere in nature. Animals and plants routinely cheat, lie and manipulate for their own benefit. One example is mimicry, where one species (the mimic) has evolved to resemble another (the model).

No group of animals takes this to greater lengths than hoverflies – bean-sized bullets that zip around your garden, cosplaying bees and wasps.

As some new research by ourselves and others show, hoverflies surprise not just their predators, but evolutionary biologists too.

Mimicry is most often for protection. Harmless mimics evade predators by evolving to resemble dangerous species. Some can even mimic several species. But mimicry can also be aggressive, where dangerous species dress up as innocuous ones to ambush unsuspecting prey, like the spider-tailed viper – or to steal food, like the rove beetle with a fake termite on its back.

It can be sexual. Flowers such as bee orchids resemble female insects to trick males into trying to copulate with them, unwittingly pollinating them in the process. Weedy male bluegill sunfish adopt the dark colouration of females to sneak into the brightly coloured alpha male’s harem and mate with the females. Some female damselflies even mimic males just to cut themselves a break from constant harassment by males for mating.

But sometimes it’s not enough just to look like your model; you have to behave like them too.

Take hoverflies, for example. Some hoverflies are highly accurate mimics, like Temnostoma. These amazingly wasp-like hoverflies have one notable flaw in their mimicry: typical short stubby fly antennae. Wasp antennae are long. But a recent study shows that Temnostoma species have evolved to mimic the long, ever-moving antennae of wasps by waving their forelegs in front of their head. Their legs have also changed from orange to black for that purpose. Stilt-legged flies do the same thing.

Other hoverflies adopt the characteristic flight patterns of their models. Butterflies mimicking other, poisonous butterflies do this too, as do spiders that walk like ants, and even a lizard that walks like a beetle.

In a new paper out this week, we and colleagues from the Universities of Hull and Nottingham showed how bumblebee-mimicking hoverflies take behavioural mimicry to the next level.

Bumblebees love blue and purple flowers, unlike wasps and many solitary bees and most flies which usually visit yellow and white flowers. A keen-eyed predator could theoretically spot a tasty fly – even one that looks like a bee – just by the colour of the flower it is visiting.

We predicted that those hoverflies that mimic bumblebees would have switched their preference to visit blue flowers. To test this we looked at nearly a thousand pictures of insects visiting flowers posted on the web by amateur enthusiasts. We looked at the colours of the flowers in the photos, comparing their “blueness” and “yellowness”.

When in Rome

Bumblebees tended to be snapped on flowers with more of a “blue” component than other insects (and less of a “yellow” component). What surprised us was how closely the mimics followed the bumblebees in the blueness of the flowers they visited.

Most likely these flies have evolved to hang out in the right places to enhance their cover story as a bumblebee. It could also be that they may have been visiting blue flowers since before they ever evolved to be mimics. This would have brought them close to bumblebees, which may have been how mimicry began evolving in the first place.

Why would this happen just in bumblebee mimics? We think we have an idea.

In nature, while some mimics are downright astonishing, like Temnostoma, or like these moths, others are really pretty ropey to the point where it’s difficult to see what they are even trying to mimic.

For protective mimicry to work, predators have to have at least one experience where they try attacking something brightly coloured to see if it is tasty, with unpleasant consequences. This teaches them to avoid these bright colours in future. In wasps, the bright colours are all broadly the same – yellow and black. This helps each individual wasp, because one clear warning signal is better than many different ones.

Do the best mimics resemble the nastiest species? Actually in many cases it’s the other way round. A recent study using 3D-printed models showed that, if your model is super-nasty, even a passing resemblance to the model will be enough for predators to avoid you.

The stronger and clearer the warning signal, the easier it is for harmless charlatans to take advantage. So you can get away with looking only a bit like a wasp.

But if you mimic a species that is only mildly noxious, you need to be super-accurate, because the predator doesn’t care as much if it makes a mistake. Bumblebees are not as nasty as wasps or honeybees. They are more palatable to predators and don’t sting as readily. So if a fly is going to mimic a bumblebee, it had better be pretty good.

And bumblebee-mimicking hoverflies are some of the best mimics in nature – right down to the kinds of flowers they visit.

James Gilbert, Senior Lecturer in Zoology, University of Hull and Lesley J. Morrell, Professor of Bioscience Education, University of Hull

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