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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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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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.

The dingo is a true-blue, native Australian species


Bradley Smith, CQUniversity Australia; Corey J. A. Bradshaw, Flinders University; Euan Ritchie, Deakin University; Justin W. Adams, Monash University; Kylie M Cairns, UNSW, and Mathew Crowther, University of Sydney

Of all Australia’s wildlife, one stands out as having an identity crisis: the dingo. But our recent article in the journal Zootaxa argues that dingoes should be regarded as a bona fide species on multiple fronts.

This isn’t just an issue of semantics. How someone refers to dingoes may reflect their values and interests, as much as the science.

How scientists refer to dingoes in print reflects their background and place of employment, and the Western Australian government recently made a controversial attempt to classify the dingo as “non-native fauna”.




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Why the WA government is wrong to play identity politics with dingoes


How we define species – called taxonomy – affects our attitudes, and long-term goals for their conservation.

What is a dog?

Over many years, dingoes have been called many scientific names: Canis lupus dingo (a subspecies of the wolf), Canis familiaris (a domestic dog), and Canis dingo (its own species within the genus Canis). But these names have been applied inconsistently in both academic literature and government policy.

This inconsistency partially reflects the global arguments regarding the naming of canids. For those who adhere to the traditional “biological” species concept (in which a “species” is a group of organisms that can interbreed), one might consider the dingo (and all other canids that can interbreed, like wolves, coyotes, and black-backed jackals) to be part of a single, highly variable and widely distributed species.

Members of the Canis genus: wolf (Canis lupus), coyote (Canis latrans), Ethiopian wolf (Canis simensis), black-backed jackal (Canis mesomelas), dingo (Canis dingo), and a representative of the domestic dog (Canis familiaris).

But the “biological” species concept used to name species came about long before modern genetic tools, or even before many hybrid species were identified by their DNA (such as the “red wolf,” an ancient hybrid of grey wolves and coyotes found in the southeastern United States).

Few people would really argue that a chihuahua, a wolf, and a coyote are the same species. In reality there are many more comprehensive and logical ways to classify a species. In our latest paper we argue that a holistic approach to defining species is essential in the case of the dingo and other canids.

Our work shows conclusively that dingoes are distinct from wild canids and domestic dogs based on many different criteria.

Truly wild

The first criterion is that dingoes are wild animals, and live completely independent from humans. This is fundamentally different to domestic, feral, or wild dogs, which must live near human settlements and rely on humans for food and water in some way to survive.

Yes, the dingo might have arrived in Australia with humans, and we know that Aboriginal Australians have had a close relationship with dingoes following the latter’s arrival. But neither of these observations excludes dingoes from being wild.




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For example, a relationship with humans does not constitute the rigorous definitions of domestication. Consider the red fox (Vulpes vulpes), which was also introduced to Australia by people and are now free-ranging: they are also not considered to be domesticated. Neither are wild animals such as birds that we feed in our backyards domesticated simply because they are sometimes fed by us.

Ecological role

In fact, dingoes have been living wild and independently of humans for a very long time — they have a distinct and unique evolutionary past that diverged some 5 to 10 thousand years ago from other canids. This is more than enough time for the dingo to have evolved into a naturalised predator now integral to maintaining the health of many Australian ecosystems.




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Dogs do not have the brain power or body adaptations to survive in the wild, and they cannot play the same ecological role as dingoes. From this ecological perspective alone, the two species are not interchangeable. Dingoes are Australia’s only large (between 15-20 kg), land-based predator, and as such play a vital role in Australia’s environment.

Shape and size

Viewed alone, the overall shape of the body and skull does not easily distinguish wild canids from dogs, mainly because of the sheer diversity among different breeds of domestic dogs.

But there are some important body differences between free-ranging dogs and dingoes, mainly in the skull region (as shown here and here).

Cranial 3-D reconstructions of a dingo (bottom) and a free-ranging dog (top), highlighting the differences in cranial morphology mentioned in the text.

Behaviour

Dingoes (and other truly wild canids) have some fundamentally unique behaviours that set them apart from dogs (although like shape, there are often exceptions among the artificial dog breeds). For example, dingoes have significantly different reproductive biology and care-giving strategies.

There are also differences in brain function, such as in the way the two species solve problems, and dingoes and dogs communicate differently with humans.




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Genetics

While dingoes and dogs obviously share an ancestral relationship, there is a lot of genetic data to support the distinction between dingoes and dogs.

While dingoes share ancestry with ancient Asian dogs from 10,000 years ago, the dingo has been geographically isolated from all other canids for many thousands of years, and genetic mixing has only been occurring recently, most probably driven by human intervention.

Since the 1990s, genetic markers have been in widespread use by land managers, conservation groups, and researchers to differentiate dingoes from domestic dogs.

A summary of the evolutionary relationships among wolves, dingoes and modern domestic dogs. Dingoes and other ancient lineages of dog such as New Guinea singing dogs form a distinct lineage separate from modern domestic dogs that have undergone successive generations of artificial selection.

What’s at stake?

Even acknowledging the dingo’s uncertain and distant past, lumping dingoes and dogs together is unjustified.

Labelling dingoes as “feral domestic dogs” or some other misnomer ignores their unique, long, and quintessentially wild history in Australia.




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Why do some graziers want to retain, not kill, dingoes?


Inappropriate naming also has serious implications for their treatment. Any label less than “dingo” can be used to justify their legal persecution.

Further loss of dingoes could have serious, negative ecological consequences, including potentially placing other Australian native animals at increased risk of extinction.The Conversation

Bradley Smith, Senior Lecturer in Psychology, CQUniversity Australia; Corey J. A. Bradshaw, Matthew Flinders Fellow in Global Ecology, Flinders University; Euan Ritchie, Associate Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University; Justin W. Adams, Senior Lecturer, Department of Anatomy and Developmental Biology, Monash University; Kylie M Cairns, Adjunct associate lecturer, UNSW, and Mathew Crowther, Associate professor, University of Sydney

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

Australia’s native rhododendrons hide in the high mountain forests



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Rhododendron lochiae, photographed on Bell Peak.
Image by Dan McLeod

Stuart Worboys, James Cook University

Sign up to the Beating Around the Bush newsletter here, and suggest a plant we should cover at batb@theconversation.edu.au.


The 1800s was a time of colonial expansion across the globe. During this time the great and the good of Britain filled their grand gardens with exotic novelties from all corners of the world.

Amongst these were many species of Asian rhododendron, a diverse and colourful genus of shrubs and small trees, whose high altitude origins made them well suited to the cool temperate climate of England and Scotland.




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Throughout the 19th century, commercial collectors and field naturalists discovered rhododendron species in southern China, the Himalayas, on the high peaks of Borneo, Java and especially New Guinea.

These finds lead Victoria’s government botanist of the time, Ferdinand von Mueller, to speculate about finding rhododendrons on the high tropical mountains on the northeast coast of Queensland. He wrote:

When in 1855 [I] saw… the bold outlines of Mount Bellenden-Ker, the highest mount of tropical Australia, towering to 5,000 feet, [I] was led to think, that the upper region might prove to be the home of species of Rhododendron… forms of plants characteristic of cool Malayan sylvan regions.

But the lofty heights of Mt Bellenden Ker were unknown to European Australians. It would be another 32 years before an expedition led by naturalist W.A. Sayer reached its central peak.



The Conversation, CC BY-ND

Sayer’s expedition, accompanied by two indigenous assistants, reached the mountain’s high ridge after several mishap-filled attempts. It was here they confirmed Mueller’s suspicions. Sayer’s account of its discovery is interesting:

The top of the range is razor-backed, and on travelling along the range beyond the spur by which we ascended, I could not see the sides, they being, if anything, hanging over. We tumbled rocks over, but could not hear them fall.

It was here that I observed the Rhodendron Lochae growing, and asked the Kanaka to get it; but he remarked, ‘S’pose I fall, I no see daylight any more; I go bung altogether;’ so I had to get it myself.

Mueller received the hard-won specimens and named the species Rhododendron lochae (later corrected to R. lochiae) after Lady Loch, the wife of the Victorian Governor.

Since then, rhododendron plants have been found on nine peaks and tablelands in the Wet Tropics region of north Queensland. Populations on peaks south of Cairns are called Rhododendron lochiae, whilst plants growing on mountains to the north of Cairns are considered by some to be a distinct species: Rhododendron viriosum.

Australian rhododendron at Smith College Botanical Garden.
Ren Glover/Flickr, CC BY-NC

Both northern and southern plants are straggly shrubs that grow in thin soils or rock cracks, sometimes in open cloud-swept boulder fields, sometimes in deep shade along creeks, or rarely as epiphytes on moss-covered trees. They produce bunches of gloriously red, bell-shaped flowers, followed by dry brown capsules filled with small winged seeds that are apparently spread by wind.

They grow slowly but with relative ease from cuttings, and are often cultivated in gardens and nurseries in temperate Australia. However, over time knowledge of the precise origin of these cultivated plants has been lost, which means they are unsuitable for detailed scientific investigations.

All of Australia’s rhododendron populations are located at altitudes above 950m in National Parks within the Wet Tropics World Heritage Area. Most are difficult to access, requiring arduous climbs on rough foot tracks through leech-infested rainforest. And yet, although isolated in protected areas, they are threatened by human activities: loss of habitat due to climate change.

Recent climate modelling research published by scientists from James Cook University and the CSIRO predicts significant reductions in suitable habitat for a suite of mountaintop flora species in Australia’s tropics (our rhododendrons were not included in the analysis, but occupy the habitats assessed).

The habitat of many of these species is predicted to disappear altogether well before the end of the century.

Conservationists are racing to preserve samples of native rhododendrons.
Author provided

Using rhododendron as a model, the Australian Tropical Herbarium at James Cook University is working to save these threatened species through “ex situ” conservation – cultivation in temperate zone public gardens, well outside their natural range. Because the threatening process – climate change – is not readily mitigated, establishing precautionary ex situ collections is the only viable conservation intervention for these plants.

With funding from the Australian Rhododendron Society Victoria Branch and the Ian Potter Foundation, and the support of traditional owners, Queensland National Parks and the Wet Tropics Management Authority, we have mounted expeditions to collect samples from most of the known populations.

These expeditions have put expert naturalists into rarely visited and challenging environments. Beyond gathering rhododendron samples, new moss species have been discovered and are being named, a fern previously thought extinct was rediscovered, and beautiful little epiphytic orchids have been found on a mountain where they’d not previously been recorded. Golden bower-bird bowers have been mapped in remote mountain rainforests, and a likely new species of snail has been discovered.




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Australia now has a well-documented and genetically diverse collection of native rhododendron plants thriving in the Dandenong Ranges Botanic Garden.

We plan to expand this work, ensuring the preservation and public display of rhododendron and many other mountain species threatened by climate change.

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Stuart Worboys, Laboratory and Technical Support Officer, Australian Tropical Herbarium, James Cook University

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

Figs, ferns and featherwoods: learn all about Australia’s native trees and plants


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You love Australian plants, I love Australian plants, we all love Australian plants!
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Madeleine De Gabriele, The Conversation and Molly Glassey, The Conversation

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Australia is classified as “megadiverse” meaning it’s a global hotspot for plant and animal diversity, and has vast numbers of unique species found nowhere else on Earth. With this newsletter we want you to be able to wander down the garden path, off the beaten track, and smell the gum leaves. Specifically, what kind of gum leaf? What is it from? Where does it grow?




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We’ll let you know every time a new edition in our Beating Around the Bush series comes out, putting the spotlight on a different native plant every time. We’re on a roughly fortnightly schedule, but like any garden there might be a few surprises along the way. I’ll also be rounding up some of the greatest hits from our archives, and talking about what’s new in the plant world.

This one is for all you floraphiles out there.
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The ConversationIf someone else in your life might enjoy this mix in their inbox, please let them know about it. And if you have any feedback, feel free to let us know in the comments.

Madeleine De Gabriele, Deputy Editor: Energy + Environment, The Conversation and Molly Glassey, Audience Development Manager, The Conversation

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