Predators, prey and moonlight singing: how phases of the Moon affect native wildlife



Wes Mountain/The Conversation, CC BY-ND

Euan Ritchie, Deakin University; Courtney Marneweck, Clemson University , and Grant Linley, Charles Sturt University

Humans have long been inspired and transfixed by the Moon, and as we’re discovering, moonlight can also change the behaviour of Australian wildlife.

A collection of recently published research has illuminated how certain behaviours of animals – including potoroos, wallabies and quolls – change with variation in ambient light, phases of the Moon and cloud cover.




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One study found small mammals were more active on cloudy nights. Another found variation in moonlight led to differing amounts of species captured in non-lethal traps. And a study on willie wagtails found males just love singing on a full moon.

These findings are interesting from a natural history perspective. But they’ll also help ecologists and conservation scientists better locate and study nocturnal animals, and learn how artificial light pollution is likely changing where animals can live and how they behave.

Moonlit predator-prey games of hide and seek

Most of Australia’s mammals are nocturnal, and some smaller species are thought to use the cover of darkness to avoid the attention of hungry predators. However, there’s much we don’t know about such relationships, especially because it can be difficult to study these interactions in the wild.

Eastern barred bandicoots became more active on darker nights.
Simon Gorta

In the relatively diverse mammal community at Mt Rothwell, Victoria, we examined how variation in ambient light affected species’ activity, and how this might influence species interactions. Mt Rothwell is a fenced conservation reserve free of feral cats and foxes, and with minimal light pollution.

Over two years, we surveyed the responses of predator and prey species to different light levels from full, half and new moon phases.




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Potential prey species in our study included eastern barred and southern brown bandicoots, long-nosed potoroos, brushtailed rock-wallabies, and brushtail and common ringtail possums. Eastern and spotted-tailed quolls are their potential predators.

Just as we predicted, we found that while there does appear to be relationships between cloud cover, Moon phase and mammal activity, these interactions depend on the sizes and types of mammals involved.

Spotted tail quoll
The spotted-tailed quoll, a meat-eating marsupial, hunts smaller prey at night.
Shutterstock

Both predators and prey generally increased their activity in darker conditions.
Smaller, prey species increased their activity when cloud cover was higher, and predators increased their activity during the half and new moon phases.

This suggests their deadly game of hide and seek might intensify on darker nights. And prey might have to trade off foraging time to reduce their chances of becoming the evening meal.

What happens in the wild?

It’s important to acknowledge that studies in sanctuaries such as Mt Rothwell might not always reflect well what goes on in the wild, including in areas where introduced predators, such as feral cats and red foxes, are found.

Another recent study, this time of small mammals in the wilds of Victoria’s Mallee region, sheds further light on the situation. The authors tested if variation in weather and Moon phase affected the numbers of five small mammal species – Bolam’s mouse, common dunnart, house mouse, southern ningaui, and western pygmy possum – captured in pitfall traps.

Ningauis are less likely to be caught in ecological surveys with increasing moonlight.
Kristian Bell

Pitfall traps are long fences small animals can’t climb over or through, so follow along the side until they fall into a bucket dug in the ground. Ecologists typically use these traps to capture and measure animals and then return them to the wild, unharmed.




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Eastern quolls edge closer to extinction – but it’s not too late to save them


At more than 260 sites and over more than 50,000 trap nights, they found wind speed, temperature and moonlight influenced which species were caught and in what numbers.

For example, captures of a small native rodent, Bolam’s mouse, and carnivorous marsupial, southern ningaui, decreased with more moonlight, whereas captures of pygmy possums were higher with more moonlight.

Variation in the moon phase and associated light can change how active mammals are.
Aaron Greenville

Moonlight songbird serenades

Research from last month has shown even species normally active by day may change their behaviour and activity by night.

It’s not uncommon to hear bird song by night, including the quintessentially Aussie warbling of magpies. Using bioacoustic recorders and song detection software, these researchers show the willie wagtail – another of Australia’s most recogisable and loved birds – is also a nighttime singer, particularly during the breeding season.

While both male and female wagtails sing by day, it is the males that are most vocal by night. And it seems the males aren’t afraid of a little stage-lighting either, singing more with increasing moonlight, with performances peaking during full moons.

While characteristically playful by day, male willie wagtails can really turn on a vocal performance by night.
Jim Bendon/Flickr

This work provides insight into the importance and potential role of nocturnal song for birds, such as mate attraction or territory defence, and helps us to better understand these behaviours more generally.

Moonlight affects wildlife conservation

These studies, and others, can help inform wildlife conservation, as practically speaking, ecological surveys must consider the relative brightness of nights during which work occurred.

Depending on when and where we venture out to collect information about species, and what methods we use (camera traps, spotlighting, and non-lethal trapping) we might have higher or lower chances of detecting certain species. And this might affect our insights into species and ecosystems, and how we manage them.

Artificial lighting can change the behaviour of wildlife.
Kenny Louie

As dark skies become rarer in many places around the world, it also begs a big question. To what extent is all the artificial light pollution in our cities and peri-urban areas affecting wildlife and ecosystems?




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Pipistrelle bats, for example, will be roughly half as active around well-lit bridges than unlit bridges. They’ll also keep further away from well-lit bridges, and fly faster when near them.

This means artificial light might reduce the amount and connectivity of habitat available to some bat species in urban areas. This, in turn could affect their populations.

Research is underway around the world, examining the conservation significance of such issues in more detail, but it’s another timely reminder of the profound ways in which we influence the environments we share with other species.


We would like to acknowledge Yvette Pauligk, who contributed to our published work at Mt Rothwell, and that the traditional custodians of this land are the Wathaurong people of the Kulin nation.The Conversation

Euan Ritchie, Associate Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University; Courtney Marneweck, Postdoctoral Researcher in Carnivore Ecology, Clemson University , and Grant Linley, PhD Candidate, Charles Sturt University

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

Don’t count your fish before they hatch: experts react to plans to release 2 million fish into the Murray Darling



Dean Lewins/AAP

Lee Baumgartner, Charles Sturt University; Jamin Forbes, Charles Sturt University, and Katie Doyle, Charles Sturt University

The New South Wales government plans to release two million native fish into rivers of the Murray-Darling Basin, in the largest breeding program of its kind in the state. But as the river system recovers from a string of mass fish deaths, caution is needed.

Having suitable breeding fish does not always guarantee millions of healthy offspring for restocking. And even if millions of young fish are released into the wild, increased fish populations in the long term are not assured.

For stocking to be successful, fish must be released into good quality water, with suitable habitat and lots of food. But these conditions have been quite rare in Murray Darling rivers over the past three years.

We research the impact of human activity on fish and aquatic systems and have studied many Australian fish restocking programs. So let’s take a closer look at the NSW government’s plans.

A mass fish kill at Menindee in northern NSW in January 2019 depleted Fisk stocks.
AAP

Success stories

According to the Sydney Morning Herald, the NSW restocking program involves releasing juvenile Murray cod, golden perch and silver perch into the Darling River downstream of Brewarrina, in northwestern NSW.

Other areas including the Lachlan, Murrumbidgee, Macquarie and Murray Rivers will reportedly also be restocked. These species and regions were among the hardest hit by recent fish kills.

Fish restocking is used worldwide to boost species after events such as fish kills, help threatened species recover, and increase populations of recreational fishing species.

Since the 1970s in the Murray-Darling river system, millions of fish have been bred in government and private hatcheries in spring each year. Young fish, called fingerlings, are usually released in the following summer and autumn.




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There have been success stories. For example, the endangered trout cod was restocked into the Ovens and Murrumbidgee Rivers between 1997 and 2006. Prior to the restocking program, the species was locally extinct. It’s now re-established in the Murrumbidgee River and no longer requires stocking to maintain the population.

In response to fish kills in 2010, the Edward-Wakool river system was restocked to help fish recover when natural spawning was expected to be low. And the threatened Murray hardyhead is now increasing in numbers thanks to a successful stocking program in the Lower Darling.

After recent fish kills in the Murray Darling, breeding fish known as “broodstock” were rescued from the river and taken to government and private hatcheries. Eventually, it was expected the rescued fish and their offspring would restock the rivers.

A Murray hardyhead after environment agencies transplanted a population of the endangered native fish.
North Central Catchment Management Authority

Words of caution

Fish hatchery managers rarely count their fish before they hatch. It’s quite a challenge to ensure adult fish develop viable eggs that are then fertilised at high rates.

Once hatched, larvae must be transported to ponds containing the right amount of plankton for food. The larvae must then avoid predatory birds, be kept free from disease, and grow at the right temperatures.




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When it comes to releasing the fish into the wild, careful decisions must be made about how many fish to release, where and when. Factors such as water temperature, pH and dissolved oxygen levels must be carefully assessed.

Introducing hatchery-reared fish into the wild does not always deliver dramatic improvements in fish numbers. Poor water quality, lack of food and slow adaptation to the wild can reduce survival rates.

In some parts of the Murray-Darling, restocking is likely to have slowed the decline in native fish numbers, although it has not stopped it altogether.

Address the root cause

Fish stocking decisions are sometimes motivated by economic reasons, such as boosting species sought by anglers who pay licence fees and support tourist industries. But stocking programs must also consider the underlying reasons for declining fish populations.

Swan Hill, home to a larger-than-life replica of the Murray cod, is just one river community that relies on anglers for tourism.
Flickr

Aside from poor water quality, fish in the Murray Darling are threatened by being sucked into irrigation systems, cold water pollution from dams, dams and weirs blocking migration paths and invasive fish species. These factors must be addressed alongside restocking.

Fish should not be released into areas with unsuitable habitat or water quality. The Darling River fish kills were caused by low oxygen levels, associated with drought and water extraction. These conditions could rapidly return if we have another hot, dry summer.

Stocking rivers with young fish is only one step. They must then grow to adults and successfully breed. So the restocking program must consider the entire fish life cycle, and be coupled with good river management.

The Murray Darling Basin Authority’s Native Fish Recovery Strategy includes management actions such as improving fish passage, delivering environmental flows, improving habitat, controlling invasive species and fish harvest restrictions. Funding the strategy’s implementation is a key next step.

Looking ahead

After recent rains, parts of the Murray Darling river system are now flowing for the first time in years. But some locals say the flows are only a trickle and more rain is urgently needed.

Higher than average rainfall is predicted between July and September. This will be needed for restocked fish to thrive. If the rain does not arrive, and other measures are not taken to improve the system’s health, then the restocking plans may be futile.




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The Conversation


Lee Baumgartner, Professor of Fisheries and River Management, Institute for Land, Water, and Society, Charles Sturt University; Jamin Forbes, Freshwater Ecologist, Charles Sturt University, and Katie Doyle, Freshwater Ecologist, Charles Sturt University

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

NSW has approved Snowy 2.0. Here are six reasons why that’s a bad move



Lucas Coch/AAP

Bruce Mountain, Victoria University and Mark Lintermans, University of Canberra

The controversial Snowy 2.0 project has mounted a major hurdle after the New South Wales government today announced approval for its main works.

The pumped hydro venture in southern NSW will pump water uphill into dams and release it when electricity demand is high. The federal government says it will act as a giant battery, backing up intermittent energy from by wind and solar.

We and others have criticised the project on several grounds. Here are six reasons we think Snowy 2.0 should be shelved.

1. It’s really expensive

The federal government announced the Snowy 2.0 project without a market assessment, cost-benefit analysis or indeed even a feasibility study.

When former Prime Minister Malcolm Turnbull unveiled the Snowy expansion in March 2017, he said it would cost A$2 billion and be commissioned by 2021. This was revised upwards several times and in April last year, Snowy Hydro awarded a A$5.1 billion contract for partial construction.

Snowy Hydro has not costed the transmission upgrades on which the project depends. TransGrid, owner of the grid in NSW, has identified options including extensions to Sydney with indicative costs up to A$1.9 billion. Massive extensions south, to Melbourne, will also be required but this has not been costed.

The Tumut 3 scheme, with which Snowy 2.0 will share a dam.
Snowy Hydro Ltd

2. It will increase greenhouse gas emissions

Both Snowy Hydro Ltd and its owner, the federal government, say the project will help expand renewable electricity generation. But it won’t work that way. For at least the next couple of decades, analysis suggests Snowy 2.0 will store coal-fired electricity, not renewable electricity.

Snowy Hydro says it will pump the water when a lot of wind and solar energy is being produced (and therefore when wholesale electricity prices are low).




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Snowy 2.0 is a wolf in sheep’s clothing – it will push carbon emissions up, not down


But wind and solar farms produce electricity whenever the resource is available. This will happen irrespective of whether Snowy 2.0 is producing or consuming energy.

When Snowy 2.0 pumps water uphill to its upper reservoir, it adds to demand on the electricity system. For the next couple of decades at least, coal-fired electricity generators – the next cheapest form of electricity after renewables – will provide Snowy 2.0’s power. Snowy Hydro has denied these claims.

Khancoban Dam, part of the soon-to-be expanded Snowy Hydro scheme.
Snowy Hydro Ltd

3. It will deliver a fraction of the energy benefits promised

Snowy 2.0 is supposed to store renewable energy for when it is needed. Snowy Hydro says the project could generate electricity at its full 2,000 megawatt capacity for 175 hours – or about a week.

But the maximum additional pumped hydro capacity Snowy 2.0 can create, in theory, is less than half this. The reasons are technical, and you can read more here.

It comes down to a) the amount of time and electricity required to replenish the dam at the top of the system, and b) the fact that for Snowy 2.0 to operate at full capacity, dams used by the existing hydro project will have to be emptied. This will result in “lost” water and by extension, lost electricity production.



The Conversation, CC BY-ND

4. Native fish may be pushed to extinction

Snowy 2.0 involves building a giant tunnel to connect two water storages – the Tantangara and Talbingo reservoirs. By extension, the project will also connect the rivers and creeks connected to these reservoirs.

A small, critically endangered native fish, the stocky galaxias, lives in a creek upstream of Tantangara. This is the last known population of the species.

The stocky galaxias.
Hugh Allan

An invasive native fish, the climbing galaxias, lives in the Talbingo reservoir. Water pumped from Talbingo will likely transfer this fish to Tantangara.

From here, the climbing galaxias’ capacity to climb wet vertical surfaces would enable it to reach upstream creeks and compete for food with, and prey on, stocky galaxias – probably pushing it into extinction.

Snowy 2.0 is also likely to spread two other problematic species – redfin perch and eastern gambusia – through the headwaters of the Murrumbidgee, Snowy and Murray rivers.




Read more:
Snowy 2.0 threatens to pollute our rivers and wipe out native fish


5. It’s a pollution risk

Snowy Hydro says its environmental impact statement addresses fish transfer impacts, and potentially serious water quality issues.

Four million tonnes of rock excavated to build Snowy 2.0 would be dumped into the two reservoirs. The rock will contain potential acid-forming minerals and other harmful substances, which threaten to pollute water storages and rivers downstream.

When the first stage of the Snowy Hydro project was built, comparable rocks were dumped in the Tooma River catchment. Research in 2006 suggested the dump was associated with eradication of almost all fish from the Tooma River downstream after rainfall.

Snowy 2.0 threatens to pollute pristine Snowy Mountains rivers.
Schopier/Wikimedia

6. Other options were not explored

Many competing alternatives can provide storage far more flexibly for a fraction of Snowy 2.0’s price tag. These alternatives would also have far fewer environmental impacts or development risks, in most cases none of the transmission costs and all could be built much more quickly.

Expert analysis in 2017 identified 22,000 potential pumped hydro energy storage sites across Australia.

Other alternatives include chemical batteries, encouraging demand to follow supply, gas or diesel generators, and re-orienting more solar capacity to capture the sun from the east or west, not just mainly the north.

Where to now?

The federal government, which owns Snowy Hydro, is yet to approve the main works.

Given the many objections to the project and how much has changed since it was proposed, we strongly believe it should be put on hold, and scrutinised by independent experts. There’s too much at stake to get this wrong.




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The Conversation


Bruce Mountain, Director, Victoria Energy Policy Centre, Victoria University and Mark Lintermans, Associate professor, University of Canberra

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

National parks are for native wildlife, not feral horses: federal court




Don Driscoll, Deakin University and Dick Williams, Charles Darwin University

Today, the federal court ruled feral horses can be removed from the Victorian high country.

The case was brought by the Australian Brumby Alliance against the Victorian Government in 2018. Since then, the strategic management plan for feral horses has been shelved, allowing feral horse numbers to increase without control.

In the northern area of Kosciuszko National Park numbers jumped from an estimated 3,255 in 2014 to 15,687 in 2019, in the absence of any management.




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Expanding numbers of feral horses roaming the Australian Alps – which are listed as a national heritage site – threaten the alp’s ecosystems, soils and unique species. More feral horses is also an animal welfare issue, as horses face starvation during droughts and have been hit by cars in Kosciuszko.

Feral horses cause extensive damage to fragile ecosystems.
Shutterstock

The ruling is a victory for national parks, which can once again be managed to protect native Australian ecosystems and species. But it stands in stark contrast to the NSW government’s controversial legal protection of feral horses.

Taken to court

The Victorian Government’s strategic action plan, released in 2017, was to remove all horses from the Bogong High Plains, where around 100 horses caused cumulative damage to sensitive alpine ecosystems.

The plan also aimed to trap horses in the eastern Victorian alps, but at a rate so low it was unlikely to make a dent in horse numbers.

Not satisfied with retaining thousands of horses in the eastern alps, in 2018, the Australian Brumby Alliance took out a court injunction to stop horse removal from the Bogong High Plains and prevent substantial reduction in horse numbers in the eastern alps.

High stakes

Twenty-five thousand feral horses in Australia’s alpine parks have damaged peat wetlands listed as threatened under federal and state legislation. Recovery will take decades to centuries.

Feral horses have also eliminated multiple populations of the native broad toothed rat and are a threat to other native species like the corroboree frog and mountain pygmy possum.

And habitat degradation and loss caused by feral horses is officially listed as a threatening process in Victoria and NSW.

Feral horse damage to a swampy area as they trample over important wetlands.
Meg McKone, Author provided

If the court had ruled in favour of the Australian Brumby Alliance’s case, it would have locked in escalating threats to the environment, including threatening already endangered species such as the alpine she-oak skink.

It would also have given at least informal legitimacy to NSW legislation that protects feral horses in Kosciuszko National Park.




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And possibly most damaging, it could have emboldened claims by brumby groups that feral horses should take priority over conservation in other contentious horse hotspots, such as Barmah, Oxley Wild Rivers, Blue Mountains, Guy Fawkes and Barrington Tops National Parks.

Feral horses have eliminated broad toothed mouse populations in the Alps.
Ken Green, Author provided

A matter of cultural heritage

The Australian Brumby Alliance argued removing horses from the alps would compromise its heritage value. They claimed feral horses are part of that heritage, including part of the mountain vistas, the pioneering heritage and myths and legends such as the Man from Snowy River.

The counterpoint from Parks Victoria was that it’s possible to remove horses from the alps while protecting the area’s cultural heritage.

It would be like taking cattle out of the high country, but nevertheless recognising pioneering exploits by preserving cattlemen’s huts.

These high plains will now be protected from feral horses.
Don Driscoll, Author provided

So what did Judge O’Bryan make of this? In a nutshell, the Australian Brumby Alliance did not have a legal hoof to stand on.

He rejected the Australian Brumby Alliance’s argument the Bogong High Plains horse population was likely to be genetically different from other feral horse populations in a way relevant to the case, and rejected claims feral horses could be beneficial to alpine ecosystems.

Judge O’Bryan also rejected the contention that the brumbies are part of the National Heritage values of the Australian Alps and accepted the evidence that feral horses cause substantial environmental damage.

The ruling acknowledged Parks Victoria’s strategic plan to control feral horses was consistent with legal obligations under the Convention on Biological Diversity, the federal EPBC (Environment Protection and Biodiversity Conservation) Act and the state’s Flora and Fauna Guarantee Act.

National parks for nature

Laws and the management of protected areas that reduce their integrity are a global concern. A 2017 study found one-third of Australia’s protected areas had been downgraded, reduced in size or had protection removed to make way for tourism ventures and other developments, like Snowy 2.0 in Kosciuszko National Park.

Kosciusko has faced the brunt of recent downgrading, notably where the NSW government voted to legally protect feral horses in 2018.

This unilateral decision has caused substantial concern for Victoria and the ACT as they face ongoing risks of feral horse incursions from NSW into their own protected areas.

The Australian Brumby Alliance’s court case threatened similar downgrading for Victoria’s alpine parks. However, state, federal and international laws, that place obligations on Australian governments to conserve native species and ecosystems in protected areas, have helped restore sensible park management.

Protecting natural heritage

Toyay’s federal court ruling upholds the right of state agencies to carry out their legal obligations. And it meets the general expectations of Australian society that our national parks exist to conserve native Australian ecosystems and species, particularly as extinction rates in Australia continue at unprecedented rates.




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It also reflects the intent of nature conservation laws. National parks are for conserving our natural heritage, the product of millions of years of evolution on this continent.

Brumby advocates concerned about recent European heritage in Australia can protect horses outside of national parks, an approach pioneered successfully in South Australia.The Conversation

Don Driscoll, Professor in Terrestrial Ecology, Deakin University and Dick Williams, Adjunct Professorial Fellow, Research Institute for the Environment and Livelihoods, Charles Darwin University

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

Snowy 2.0 threatens to pollute our rivers and wipe out native fish



Schopier/Wikimedia

John Harris, UNSW and Mark Lintermans, University of Canberra

The federal government’s Snowy 2.0 energy venture is controversial for many reasons, but one has largely escaped public attention. The project threatens to devastate aquatic life by introducing predators and polluting important rivers. It may even push one fish species to extinction.

The environmental impact statement for the taxpayer-funded project is almost 10,000 pages long. Yet it fails to resolve critical problems, and in one case seeks legal exemptions to enable Snowy 2.0 to wreak environmental damage.

The New South Wales government is soon expected to grant the project environmental approval. This process should be suspended, and independent experts should urgently review the project’s environmental credentials.

Native fish extinctions

Snowy Hydro Limited, a Commonwealth-owned corporation, is behind the Snowy 2.0 project in the Kosciuszko National Park in southern NSW. It involves building a giant tunnel to connect two water storages – the Tantangara and Talbingo reservoirs. By extension, the project will also connect the rivers and creeks connected to these reservoirs.

A small, critically endangered native fish, the stocky galaxias, lives in a creek upstream of Tantangara. This is the last known population of the species.




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An invasive native fish, the climbing galaxias, lives in the Talbingo reservoir (it was introduced from coastal streams when the original Snowy project was built). Water pumped from Talbingo will likely transfer this fish to Tantangara.

From here, the climbing galaxias’ capacity to climb wet vertical surfaces would enable it to reach upstream creeks and compete for food with, and prey on, stocky galaxias – probably pushing it into extinction.

The stocky galaxias.
Hugh Allan

Snowy Hydro has applied for an exemption under NSW biosecurity legislation to permit the transfer of the climbing galaxias and two other fish species: the alien, noxious redfin perch and eastern gambusia.

Redfin perch compete for food with other species and produce many offspring. They are voracious, carnivorous predators, known to prey on smaller fish.

Redfin perch also allow the establishment of a fatal fish disease – epizootic haematopoietic necrosis virus – or EHN. This disease kills the endangered native Macquarie perch, the population of which below Tantangara is one of very few remaining.

If Snowy 2.0 is granted approval, it is likely to spread these problematic species through the headwaters of the Murrumbidgee, Snowy and Murray rivers.

The climbing galaxias, which threatens the native stocky galaxias.
Stella McQueen/Wikimedia

Acid and asbestos pollution

Four million tonnes of rock excavated to build Snowy 2.0 would be dumped into the two reservoirs. Snowy Hydro has not assessed the pollution risks this creates. The rock will contain potential acid-forming minerals and a form of asbestos, which threaten to pollute water storages and rivers downstream.

When the first stage of the Snowy Hydro project was built, comparable rocks were dumped in the Tooma River catchment. Research in 2006 suggested the dump was associated with eradication of almost all fish from the Tooma River downstream after rainfall.




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Addressing the problems

The environmental impact statement either ignores, or pays inadequate attention to, these environmental problems.

For example, installing large-scale screens at water inlets would be the best way to prevent fish transfer from Talbingo Dam, but Snowy Hydro has dismissed it as too costly.

Snowy Hydro instead proposes a dubious second-rate measure: screens to filter pumped flows leaving Tantangara reservoir, and building a barrier in the stream below the stocky galaxias habitat.

The best and cheapest way to prevent damage from alien species is stopping the populations from establishing. Trying to control or eradicate pest species once they’re established is far more difficult and costly.



The Conversation, CC BY-ND

We believe the measures proposed by Snowy Hydro are impractical. It would be very difficult to maintain a screen fine and large enough to prevent fish eggs and larvae moving out of Tantangara reservoir and such screens would be totally ineffective at preventing the spread of EHN virus.

A six metre-high waterfall downstream of the stocky galaxias habitat currently protects the critically endangered species from other invasive species threats. But climbing galaxias have an extraordinary ability to ascend wet surfaces. They would easily climb the waterfall, and possibly the proposed creek barrier as well.

Such an engineered barrier has never been constructed in Australia. We are informed that in New Zealand, the barriers have not been fully effective and often require design adjustments.




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Even if the barrier protected the stocky galaxias at this location, efforts to establish populations in other unprotected regional streams would be severely hampered by the spread of climbing galaxias.

Preventing redfin and EHN from entering the Murrumbidgee River downstream of Tantangara depends on the reservoir never spilling. The reservoir has spilled twice since construction in the 1960s, and would operate at much higher water levels when Snowy 2.0 was operating. Despite this, Snowy Hydro says it has “high confidence in being able to avoid spill”.

If dumped spoil pollutes the two reservoirs and Murrumbidgee and Tumut rivers, this would also have potentially profound ecological impacts. These have not been critically assessed, nor effective prevention methods identified.

The Tumut 3 scheme, part of the existing Snowy Hydro scheme.
Snowy Hydro Ltd

Looking to the future

Snowy 2.0 will likely make one critically endangered species extinct and threaten an important remaining population of another, as well as pollute freshwater habitats. As others have noted, the project is also questionable on other environmental and economic grounds.

These potential failures underscore the need to immediately halt Snowy 2.0, and subject it to independent expert scrutiny.


In response to the issues raised in this article, a spokesperson for Snowy Hydro said:

“Snowy Hydro’s EIS, supported by numerous reports from independent scientific experts, extensively address potential water quality and fish transfer impacts and the risk mitigation measures to be put in place. As the EIS is currently being assessed by the NSW Government we have no further comment.”


A previous version of this article incorrectly stated that water pumped from Tantangara will likely transfer fish to Talbingo. It should have said water pumped from Talbingo will likely transfer fish to Tantangara.The Conversation

John Harris, Adjunct Associate Professor, Centre for Ecosystem Science, UNSW and Mark Lintermans, Associate professor, University of Canberra

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

Yes, native plants can flourish after bushfire. But there’s only so much hardship they can tak



Bulbine lilies flowering and eucalypts resprouting after fire in the Victorian high country.
Heidi Zimmer

Lucy Commander, University of Western Australia and Heidi Zimmer, Southern Cross University

In a fire-blackened landscape, signs of life are everywhere. A riot of red and green leaves erupt from an otherwise dead-looking tree trunk, and the beginnings of wildflowers and grasses peek from the crunchy charcoal below.

Much Australian flora has evolved to cope with fire, recovering by re-sprouting or setting seed. However, some plants are sensitive to fire, especially when fires are frequent or intense, and these species need our help to recover.




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After announcing a A$50 million wildlife and habitat recovery package, the Morrison government recently met with Australia’s leading wildlife experts to steer recovery efforts.

Encouraging native flora to bounce back from these unprecedented fires requires targeted funding and actions to conserve and restore plants and ecological communities, including seed banking.

How do plants naturally recover from fire?

Many plants from fire-prone ecosystems have evolved strategies to survive, and even thrive, with fire. Some resprout after fire, with green shoots bursting from blackened stems. For others, fire stimulates flowering.

Some species are able to resprout from blackened stems following a fire.
Lucy Commander, Author provided

Fire can also trigger seed germination of hundreds of species, as seeds respond to fire “cues” like heat and smoke.

Seeds may wait in woody fruits stored on the plant. The fruits’ hard capsules shield the seeds from the fire, but the heat opens the capsules, releasing seeds into the soil below.

We can capitalise on this natural recovery by not disturbing the soil where the seeds are scattered, not clearing “dead” plants which may resprout and provide shelter for remaining wildlife, including perches for birds who may bring in seeds.

We should also stop vegetation clearing, especially unburnt vegetation home to threatened species and communities.

Some species, like this Banksia, have woody fruits that protect the seeds, then open after fire to release them.
Lucy Commander, Author provided

When do we need to intervene?

While Australian plants and ecosystems have evolved to embrace bushfires, there’s only so much drought and fire they can take.

Many plants and ecosystems, including alpine and rainforest species, are not resilient to fire, especially if drought persists or they have been burnt too frequently. Too frequent fires deplete the seed bank and put recovery at risk.

Fires which are intense and severe will outright kill other plants, or the plants will be very slow to recover – taking years or decades to reach maturity again. We need comprehensive monitoring to detect which species are not returning, with systematic field surveys starting immediately, and continuing after the first rains to identify which species emerge from the soil.

Some ecosystems are adapted to fire, with trees resprouting and seeds germinating from the soil seed bank. Even so, fencing and weed control may be required.
Lucy Commander, Author provided

Invasive plants such as blackberry or veldt grass can also impede recovery after a fire by out-competing the natives. Feral herbivores – such as rabbits, goats and horses – can overgraze the native regrowth. So controlling the weeds and feral grazers with, for instance, temporary fencing and tree guards, is a priority post-fire.

And when ecosystems aren’t able to repair themselves, it’s up to us to intervene. For instance, land managers, supported by volunteer community groups, could sow seeds or plant seedlings in fire-affected areas. This act of restoring ecosystems can be an important healing process for those affected by the fires.

Do we have enough seeds?

But for that to happen, we need enough seeds to supply restoration efforts. With millions of hectares already burnt, few areas may be left for seed collection.

This means unburnt areas are at risk of over-collection from commercial and volunteer seed collectors. Stopping this from happening is possible, however. The agencies giving out permits for seed collection must record where seeds are being sourced and how much is collected. This ensures areas aren’t stripped of seeds, rendering them less resilient.




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Another, more controversial issue, is whether seeds should be collected locally (perhaps within 20km or within the catchment), or from somewhere much further away and more suited to a potential future climate.

And what should we do if we lose a population of a threatened plant species? Establishing a new population or replacing a lost one using translocation is one option. Similar to capture-and-release or zoo breeding programs for reintroduction of threatened animals, translocation refers to deliberately moving plants or seeds to a new location.

How can we better prepare for next time?

With potentially more unprecedented bushfire seasons in our future, it’s important land managers are prepared.

They need data on the distribution of species and the fire frequency, severity and season they can tolerate. A nationwide database could identify which species and ecosystems are most at risk, and could be incorporated into fire and restoration planning – including seed collecting – to ensure plant material is available if species fail to recover.




Read more:
‘Plant blindness’ is obscuring the extinction crisis for non-animal species


Botanic gardens have a special role to play as many already have conservation seed banks of threatened species, and their living collections provide additional genetic material. Across Australia there is already a network of seed banks collaborating through the Australian Seed Bank Partnership that collect, store and undertake research to better support plant conservation.

A restoration seed bank in Utah, USA. These banks hold huge amounts of seeds, but the Australian equivalents operate on a smaller scale.
Lucy Commander

However, restoration seed banks operate on a much larger scale than botanic gardens, and it’s important both approaches are conducted collaboratively. We need more ongoing investment in seed banks, particularly for threatened species and ecosystems least likely to recover from repeat fires like rainforests. Investment in skilled staff to run them is also critical, as well as national guidelines for seed use and training programs for staff and volunteers.

The recent bushfires will push many plant species to their limits. If we want to keep these species around – and the animals depend on them for food and habitat – we need to monitor their recovery and intervene where necessary.The Conversation

Lucy Commander, Adjunct Lecturer, University of Western Australia and Heidi Zimmer, Research associate, Southern Cross University

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

Most native bird species are losing their homes, even the ones you see every day



Eastern-yellow robin. Some 60 per cent of the native birds of south-east mainland Australia have lost more than half of their natural habitat.
Graham Winterflood/Wikimedia Commons

Jeremy Simmonds, The University of Queensland; Alvaro Salazar, The University of Queensland; James Watson, The University of Queensland, and Martine Maron, The University of Queensland

Across parts of Australia, vast areas of native vegetation have been cleared and replaced by our cities, farms and infrastructure. When native vegetation is removed, the habitat and resources that it provides for native wildlife are invariably lost.

Our environmental laws and most conservation efforts tend to focus on what this loss means for species that are threatened with extinction. This emphasis is understandable – the loss of the last individual of a species is profoundly sad and can be ecologically devastating.




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But what about the numerous other species also affected by habitat loss, that have not yet become rare enough to be listed as endangered? These animals and plants — variously described as “common” or of “least concern” — are having their habitat chipped away. This loss usually escapes our attention.

These common species have intrinsic ecological value. But they also provide important opportunities for people to connect with nature – experiences that are under threat.

A chain used for land clearing is dragged over a pile of burning wood at a Queensland property.
Dan Peled/AAP

The “loss index”: tracking the destruction

We developed a measure called the loss index to communicate how habitat loss affects multiple Australian bird species. Our measure showed that across Victoria, and into South Australia and New South Wales, more than 60% of 262 native birds have each lost more than half of their original natural habitat. The vast majority of these species are not formally recognised as being threatened with extinction.

It is a similar story in the Brigalow Belt of central New South Wales and Queensland. The picture is brighter in the northern savannas across the top of Australia, where large tracts of native vegetation remain – notwithstanding pervasive threats such as inappropriate fire regimes.




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We also found that in some areas, such as Southeast Queensland and the Wet Tropics region of north Queensland, the removal of a single hectare of forest habitat can affect up to 180 different species. In other words, small amounts of loss can affect large numbers of (mostly common) species.

Our index allowed us to compare how different groups of birds are impacted by habitat loss. Australia’s iconic parrots have been hit hard by habitat loss, because many of these birds occur in the places where we live and grow our food. Birds of prey such as eagles and owls have, as a group, been less affected. This is because many of these birds occur widely across Australia’s less developed arid interior.

This map shows the number of bird species affected by habitat loss in any region. Grey zones indicate parts of Australia where habitat loss has not occurred. Blue zones have up to 90 species affected by habitat loss, yellow is up to 120 species affected, while the highest category, red, is up to 187 species affected.
Conservation Biology

Habitat loss means far fewer birds

Our study shows many species have lost lots of habitat in certain parts of Australia. We know habitat loss is a major driver of population declines and freefalling numbers of animals globally. A measure of vertebrate population trends — the Living Planet Index — reveals that populations of more than 4,000 vertebrate species around the world are on average less than half of what they were in 1970.

In Australia, the trend is no different. Populations of our threatened birds declined by an average of 52% between 1985 and 2015. Alarmingly, populations for many common Australian birds are also trending downwards, and habitat loss is a major cause. Along Australia’s heavily populated east coast, population declines have been noted for many common species including rainbow bee-eater, double-barred finch, and pale-headed rosella.

Decling common species – rainbow bee-eater (left); double-barred finch (top right); pale-headed rosella (bottom right)
Jim Bendon, G. Winterflood, Aviceda



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This is a major problem for ecosystem health. Common species tend to be more numerous and so perform many roles that we depend on. Our parrots, pigeons, honeyeaters, robins, and many others help pollinate flowers, spread seeds, and keep pest insects in check. In both Europe and Australia, declines in common species have been linked to a reduction in the provision of these vital ecosystem services.

Common species are also the ones that we most associate with. Because they are more abundant and familiar, these animals provide important opportunities for people to connect with nature. Think of the simple pleasure of seeing a colourful robin atop a rural fence post, or a vibrant parrot dashing above the treetops of a suburban creek. The decline of common species may contribute to diminished opportunities for us to interact with nature, leading to an “extinction of experience”, with associated negative implications for our health and well-being.

We mustn’t wait until it’s too late

Our study aims to put the spotlight on common species. They are crucially important, and yet the erosion of their habitat gets little focus. Conserving them now is sensible. Waiting until they have declined before we act will be costly.

These species need more formal recognition and protection in conservation and environmental regulation. For example, greater attention on common species, and the role they play in ecosystem health, should be given in the assessment of new infrastructure developments under Australia’s federal environment laws (formally known as the Environment Protection and Biodiversity Conservation Act 1999).

We should be acting now to conserve common species before they slide towards endangerment. Without dedicated attention, we risk these species declining before our eyes, without us even noticing.The Conversation

Jeremy Simmonds, Postdoctoral Research Fellow in Conservation Science, The University of Queensland; Alvaro Salazar, Postdoctoral Research Fellow, The University of Queensland; James Watson, Professor, The University of Queensland, and Martine Maron, ARC Future Fellow and Professor of Environmental Management, The University of Queensland

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

Eat your heart out: native water rats have worked out how to safely eat cane toads



Water rats in Western Australia are safely hunting cane toads.
Author provided

Marissa Parrott, University of Melbourne; Sean Doody, University of Newcastle, and Simon Clulow, Macquarie University

Australia’s water rats, or Rakali, are one of Australia’s beautiful but lesser-known native rodents. And these intelligent, semi-aquatic rats have revealed another talent: they are one of the only Australian mammals to safely eat toxic cane toads.

Our research, published today in Australian Mammalogy, found water rats in Western Australia adapted to hunt the highly poisonous toads less than two years after the toads moved into the rats’ territory.




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The rats, which can grow to over 1kg, are the only mammal found to specifically target large toads, neatly dissecting the toads to eat their hearts and livers while avoiding the poisonous skin and glands.

Water rats

Water rats are nocturnal and specially adapted to live in waterways, with webbed feet and soft water-resistant fur. Their fur is so impressive there was once a thriving water rat fur industry in Australia.

They can be found in lakes, rivers and estuaries, often living alongside people, in New South Wales, Queensland, Tasmania, South Australia, far north and southwest Western Australia, the Northern Territory, and Victoria, where they can even be seen along St Kilda Pier.

Water rats are also highly intelligent, as shown by their rapid adaptation to hunting and eating one of Australia’s most toxic introduced species – the invasive cane toad.

Cane toads were introduced to Australia in 1935 in an ill-fated attempt to control the cane beetle. They have spread across the north of the country at up to 60km per year, leaving devastation in their wake. Many native species, such as northern quolls, yellow-spotted monitors, and crocodiles, have suffered widespread declines, and in some cases local extinctions, as a result of eating cane toads.

The toads secrete a toxin in their parotoid glands (on the back, neck and shoulders) that can be fatal even in very small doses.

A cane toad at our field site in the Kimberley.
Marissa Parrott, Author provided

Eat your heart out

Cane toads arrived at our field site in the Kimberley, Western Australia, in 2011-12, leading to a crash in the populations of predators including numerous lizards and northern quolls.

However, in 2014 we found a creek dotted with the bodies of cane toads that had clearly been attacked. Every morning we discovered up to five new dead toads with small, near-identical incisions down their chest in just a five-metre stretch of creek. What was using almost surgical precision to attack these toads?

Post-mortem analysis showed that in larger toads the heart and liver had been removed, and the gall bladder (which contains toxic bile salts) neatly moved outside the chest cavity. In medium-sized toads, besides the removal of the heart and liver, one or both back legs had been stripped of their toxic skin and the muscle also eaten.

The finding intrigued us enough to dissect waterlogged and rotting toad bodies in 40℃ heat. Using remote infrared camera footage and analysis of the bites left on the muscle, we found our clever attacker – the native water rat!

A water rat caught on camera hunting for cane toads in the Kimberley.
Marissa Parrott, Author provided

What kind of toads are rats eating?

While there have been anecdotal reports of water rats eating toads in Queensland and the Northern Territory, there were no published reports of this in Western Australia, where the toad was a more recent arrival.

We also didn’t know whether rats could tolerate the toad toxins, or were targeting non-toxic parts of the body. And we wanted to find out whether the rats were targeting small (and less toxic) toads, as some other rodent species do, or were deliberately going after larger toads which are a better source of food.

During our study we captured and measured more than 1,800 cane toads in just 15 days in the vicinity of the water rats’ creek. The vast majority, 94%, were medium-sized; 3.5% were small (less than 4cm long); and just 2.5% were large (greater than 10cm long).

But despite medium toads being far more common, three quarters of the dead toads we found were large, and the remainder were medium. No small toad bodies were found or observed being attacked.

While some species, such as keelback snakes and several birds (including black and whistling kites, and crows) can eat cane toads, there has been less evidence of mammals hunting this new type of prey and living to tell the tale.

Some rodents can eat small juvenile toads, but no rodents have been documented specifically targeting large toads. In our case, water rats preferred to eat large toads, despite medium-sized toads outnumbering them by 27 to 1.

A water rat eating at Healesville Sanctuary.

We’re not sure whether water rats have very rapidly learned how to safely attack and eat cane toads, or if they are adapting a similar long-term hunting strategy that they may use to eat toxic native frogs.

Water rats are very well placed to pass on hunting strategies, as they care for their offspring for at least four weeks after they finish producing milk. This could help spread the knowledge of toad hunting across streams and creeks over time.




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While this behaviour seems to be confined to local populations, if these tactics spread, water rats may be able to suppress toad populations when they reach water bodies – another small line of defence against this toxic killer.The Conversation

Marissa Parrott, Reproductive Biologist, Wildlife Conservation & Science, Zoos Victoria, and Honorary Research Associate, BioSciences, University of Melbourne; Sean Doody, Conjoint Fellow, University of Newcastle, and Simon Clulow, MQ Research Fellow, Macquarie University

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

What are native grasslands, and why do they matter?



The Southern Tablelands contain rare native grasslands.
Tim J Keegan/Flickr, CC BY-SA

Mike Letnic, UNSW

Coalition minister Angus Taylor is under scrutiny for possibly intervening in the clearing of grasslands in the southern highlands of New South Wales. Leaving aside the political dimensions, it’s worth asking: why do these grasslands matter?




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The grasslands in much of eastern Australia are the result of forests and woodlands cleared to “improve” the landscape (from a grazier’s point of view) to make it suitable for grazing livestock.

The “improvment” typically entails cutting trees, burning the felled timber and uprooting tree stumps, followed by ploughing, fertilising and sowing introduced grasses that are more palatable to livestock than many native grasses.

However, largely treeless native grasslands once occurred at high elevations across much of the Monaro tableland, in the area stretching between Canberra and Bombala.

The Monaro grasslands (or in scientific speak, the natural temperate grassland of the Southern Tablelands) are in relatively dry and cold areas, particularly in upland valleys or frost hollows where cold air descends at night.

The combination of dry climate and cold restricts tree growth and instead has encouraged grasses and herbs. Native grasses such as kangaroo grass and poa tussock dominate the grasslands, but there are many other unique plants. A typical undisturbed grassland area will support 10-20 species of native grasses and 40 or more non-grass species.




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The grassy plains are also home to unique cold-adapted reptiles such as the grass-land earless dragon, little whip snake, pink-tailed worm lizard and striped legless lizards. This combination of plants and animals create a unique ecological community.

Striped legless lizards may resemble a snake, but most of its body is actually tail. It has vestigial limbs and a non-forked tongue.
Benjamint444/Wikipedia, CC BY-NC-SA

A fraction remain

It is estimated only 0.5% of the area that would once have been natural temperate grasslands in the Southern Tablelands remains. The rest has been gradually “improved” since the mid-nineteenth century to make them more productive for livestock grazing.

Livestock dramatically change the composition of grasslands, as animals remove palatable plants and compact the soil under their weight. Disturbed soil and the livestock also help to spread non-native weeds.

However, most native grasslands have not just been modified by grazing but completely replaced by man-made pastures. That is, the land has been ploughed, fertilised and the seeds of introduced grasses have been planted.




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These changes to the landscape mean much of the landscape is dominated by introduced plants and is now unsuitable for many of the native plants and animals that once lived and grew there.

Because the Natural Temperate Grassland of the Southern Tablelands is now so rare it is classified as critically endangered and federally protected. Furthermore, many of the distinct plants and animals that still live in these grasslands are classified as vulnerable or endangered.

The pink-tailed worm lizard is one of the rare species living in the native grasslands of the Southern Tablelands.
Matt Clancy/Wikimedia Commons, CC BY-SA

Some of the best remaining examples of the Monaro grasslands can be found in old cemeteries and in areas set aside as public livestock grazing areas. These areas of public land have often been spared from pasture improvement or only lightly grazed, and thus now support relatively intact native grassland ecosystems.




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While, to the untrained eye the Monaro grasslands may seem unremarkable and difficult to distinguish from grazing pastures, they are deeply important. They show us what Australia once looked like, and act as a haven for native biodiversity.

Indeed, what remains of the natural grasslands is now so disturbed by agriculture there is a real threat this distinctive ecological community and many of the species it contains may disappear altogether, if they are not protected from excessive grazing, fertilisers and the plough.The Conversation

Mike Letnic, Professor, Centre for Ecosystem Science, UNSW

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

Logged native forests mostly end up in landfill, not in buildings and furniture



File 20190409 2905 7sdxsi.jpg?ixlib=rb 1.1
Almost all native forest logging in Victoria is for woodchips, pulp and pallets, which have short lifespans before going to landfill.
Janelle Lugge/Shutterstock

Chris Taylor, Australian National University and David Lindenmayer, Australian National University

Victoria has some of the most carbon-dense native forests in the world. Advocates for logging these forests often argue that wood products in buildings and furniture become long-term storage for carbon.

However, these claims are misleading. Most native trees cut down in Victoria become woodchips, pulp and pallets, which have short lifespans before going to landfill. In landfill, the wood breaks down and releases carbon back into the atmosphere.

On the other hand, our evolving carbon market means Australia’s native forests are extremely valuable as long-term carbon stores. It’s time to recognise logging for short-lived wood products is a poor use of native forests.




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The problem with logging native forests

Victoria has about 7.6 million hectares of native forests. The most carbon-dense areas are in ash forests, consisting of mountain ash, alpine ash and shining gum trees.

These forests can store up to 1,140 tonnes of carbon per hectare for centuries.

Only 14% of logs cut from Victorian native forests end up as timber products used in buildings and furniture.
Shutterstock

But around 1.82 million hectares of Victorian native forests are allocated to the government’s logging business, VicForests.

VicForests claims logging is the only market for the large area of native forest allocated to it. In other words, its forests are exclusively valued as timber asset, in the same way a wheat crop would be exclusively valued for wheat grain production.

In Victorian native forests, industrial scale clearfell logging removes around 40% of the forest biomass for logs fit for sale.

The remaining 60% is debris, which is either burned off or decomposes – becoming a major source of greenhouse gas emission.




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Myth one: storing carbon in wood products

The first myth we want to address is logging native forests is beneficial because the carbon is stored in wood products. This argument depends on the proportion of forest biomass ending up in wood products, and how long they last before ending up in landfill.

On average, logs suitable to be sawn into timber make up only an average 35% of total logs cut from Victorian native forests.

Of this 35%, sawmills convert less than 40% into sawn timber for building and furniture. Offcuts are woodchipped and pulped for paper manufacturing, along with sawdust sold to chicken broiler sheds for bedding.

Sawn timber equates to 14% of log volume cut from the forest. The remaining 84% of logs cut are used in short-lived and often disposable products like copy paper and pallets.




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Forest soil needs decades or centuries to recover from fires and logging


The lifespan of paper products is assumed to be three years. Although around 75% of paper and cardboard is recovered, recycling is growing more uncertain with recovered paper being sent to landfill.

The maximum lifespan of a timber pallet is seven years. At the end of their service, timber pallets are sent to landfill, chipped for particleboard, reused for landscape mulch or burnt for energy generation.

Longer-lived wood products, such as the small proportion of native timber used in building and furniture, have a lifespan of around 90 years. These wood products are used to justify logging native forests.

But at the end of their service life, the majority of these wood products also end up in landfill.

In fact, for the 500,000 tonnes of wood waste generated annually from building, demolition and other related commercial processes in Victoria, over two thirds end up in landfill, according to a Sustainability Victoria report.

Myth two: the need to log South East Asian rainforests

A second myth is using logs from Victorian native forests will prevent logging and degradation of rainforests across South East Asia, particularly for paper production.

This is patently absurd. The wood from the Victorian plantation sector – essentially timber farms, rather than trees growing “wild” in native forests – could replace native forest logs used for paper manufacturing in Victoria several times over.

In fact, in 2016-17 89% of logs used to make wood pulp (pulplogs) for paper production in Victoria came from plantation trees, with the majority of hardwood logs exported.

And Australia is a net exporter by volume of lower-value unprocessed logs and woodchips.




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Native forests can help hit emissions targets – if we leave them alone


Processing pulplogs from well managed plantations in Victoria instead of exporting them would give a much needed jobs boost for local economies.

With most of these plantations established on previously cleared farmland, they offer one of the most robust ways for the land use sector to off-set greenhouse gas emissions.

Next steps

The time is right for Australian governments to develop a long-term carbon storage plan that includes intact native forests.

Logging results in at least 94% of a forest’s stored carbon ending up in the atmosphere. A maximum of 6% of its carbon remains in sawn timber, for up to 90 years (but typically much shorter). This is patently counterproductive from a carbon-storage point of view.




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State-owned forest management companies, such as VicForests, can transition away from the timber business and begin managing forests for carbon storage. Such a concept is not new – the federal government has already approved a way to value the carbon storage of plantations.

The same must now be developed to better protect native forests and the large amounts of carbon they can store.The Conversation

Chris Taylor, Research Fellow, Fenner School of Environment and Society, Australian National University and David Lindenmayer, Professor, The 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.