How Australian wildlife spread and suppress Ross River virus



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Mozzies feed on many native species, including the Nankeen Night Heron.
Janis Otto/flikr

Eloise Stephenson, Griffith University; Cameron Webb, University of Sydney, and Emily Johnston Flies, University of Tasmania

Ross River virus is Australia’s most common mosquito-borne disease. It infects around 4,000 people a year and, despite being named after a river in North Queensland, is found in all states and territories, including Tasmania.

While the disease isn’t fatal, it can cause debilitating joint pain, swelling and fatigue lasting weeks or even months. It can leave sufferers unable to work or look after children, and is estimated to cost the economy A$2.7 to A$5.6 million each year.

There is no treatment or vaccine for Ross River virus; the only way to prevent is to avoid mosquito bites.




Read more:
Explainer: what is Ross River virus?


Mosquitoes pick up the disease-causing pathogen by feeding on an infected animal. The typical transmission cycle involves mosquitoes moving the virus between native animals but occasionally, an infected mosquito will bite a person. If this occurs, the mosquito can spread Ross River virus to the person.

Animal hosts

Ross River virus has been found in a range of animals, including rats, dogs, horses, possums, flying foxes, bats and birds. But marsupials – kangaroos and wallabies in particular – are generally better than other animals at amplifying the virus under experimental infection and are therefore thought to be “reservoir hosts”.

The virus circulates in the blood of kangaroos and wallabies for longer than other animals, and at higher concentrations. It’s then much more likely to be picked up by a blood-feeding mosquito.

Kangaroos are a common sight around Australia’s coastal wetlands.
Dr Cameron Webb (NSW Health Pathology), Author provided

Dead-end hosts

When we think of animals and disease we often try to identify which species are good at transmitting the virus to mosquitoes (the reservoir hosts). But more recently, researchers have started to focus on species that get bitten by mosquitoes but don’t transmit the virus.

These species, known as dead-end hosts, may be important for reducing transmission of the virus.

With Ross River virus, research suggests birds that get Ross River virus from a mosquito cannot transmit the virus to another mosquito. If this is true, having an abundance of birds in and around our urban environments may reduce the transmission of Ross River virus to animals, mosquitoes and humans in cities.

Other reservoir hosts?

Even in areas with a high rates of Ross River virus in humans, we don’t always find an abundance of kangaroos and wallabies. So there must be other factors – or animals yet to be identified as reservoirs or dead-end hosts – playing an important role in transmission.

Ross River virus is prevalent in the Pacific Islands, for instance, where there aren’t any kangaroos and wallabies. One study of blood donors in French Polynesia found that 42.4% of people tested had previously been exposed to the virus. The rates are even higher in American Samoa, where 63% of people had been exposed.




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The worst year for mosquitoes ever? Here’s how we find out


It’s unclear if the virus has recently started circulating in these islands, or if it’s been circulating there longer, and what animals have been acting as hosts.

What about people?

Mosquitoes can transmit some viruses, such as dengue and Zika between people quite easily.

But the chances of a mosquito picking up Ross River virus when biting an infected human is low, though not impossible. The virus circulates in our blood at lower concentrations and for shorter periods of time compared with marsupials.

Stop mozzies biting with insect repellents.
Elizaveta Galitckaia/Shutterstock

If humans are infected with Ross River virus, around 30% will develop symptoms of joint pain and fatigue (and sometimes a rash) three to 11 days after exposure, while some may not experience any symptoms until three weeks after exposure.

To reduce your risk of contracting Ross River virus, take care to cover up when you’re outdoors at sunset and wear repellent when you’re in outdoor environments where mosquitoes and wildlife may be frequently mixing.




Read more:
Mozzie repellent clothing might stop some bites but you’ll still need a cream or spray


The Conversation


Eloise Stephenson, PhD Candidate, Griffith University; Cameron Webb, Clinical Lecturer and Principal Hospital Scientist, University of Sydney, and Emily Johnston Flies, Postdoctoral Research Fellow (U.Tasmania), University of Tasmania

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

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What happens after you take injured wildlife to the vet?



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Many Australians bring injured wild animals to vets, but not many people know what happens next.
RSPCA ACT

Bronwyn Orr, University of Sydney

Australia’s wildlife is unique and endearing, with many species found nowhere else in the world. Unfortunately, it isn’t rare to encounter sick or injured wildlife around your home or by the side of the road. My research, recently published in the Australian Veterinary Journal, estimates between 177,580 and 355,160 injured wild animals are brought into NSW veterinary clinics alone every year.

But until now, very little was known about what happens to wildlife after they’re brought to a vet. My colleagues and I surveyed 132 veterinary clinics around Australia, examining the demands and expectations of treating wildlife. We also looked for risks to animal welfare as a result of these findings.

Most clinics only saw a handful of wildlife patients every week, with birds and marsupials such as possums the most common. Sadly, the majority (82%) of wildlife arrived in veterinary care due to trauma of some kind. The most common cause was animals being hit by cars, followed by undefined trauma and predation by another animal.




Read more:
Want to help animals? Don’t forget the chickens


Most clinics examined and treated wildlife for free, with less than 10% receiving some kind of payment. These were usually made by wildlife rehabilitation groups or members of the public.

Due to the painful and serious nature of trauma, around a third of clinics reported euthanasia was the most common outcome for wildlife at their clinic. More positively, more than half indicated that wildlife were usually passed onto wildlife rehabilitators, suggesting this is the most common outcome.

Kangaroo with burns to all four limbs after a fire.
Author Provided

Almost three quarters of veterinary clinics said they only saw wildlife when they had spare time. This is concerning, as delays to treatment raises serious animal welfare concerns.

Additionally, many veterinary clinics indicated they felt a lack of time, knowledge and skills interfered with their ability to treat wildlife.

As veterinary clinics are small businesses, wildlife present a conundrum. They are not owned (although technically they are owned by the Crown), expect treatment with no payment and don’t look like the usual pets seen by most vets. With clinics full of paying clients expecting prompt treatment, it can be hard to prioritise wildlife.

So what is the solution?

Ideally, either the state or federal government would take financial responsibility for wildlife. The federal government does pay for some wildlife treatment at private veterinary clinics, but this is part of a biosecurity monitoring scheme and isn’t open to most clinics.




Read more:
How dogs and cats can get their day in court


Donations from the public to treat wildlife would also likely be welcomed. However, help can come in other ways. One large clinic in Sydney is trialling an in-house wildlife carer, who would triage wildlife and take responsibility for ensuring wildlife are prioritised. Appointing a “wildlife champion” in a clinic is another option, where an interested vet or nurse is designated the “go to” person for wildlife cases.

Wombat in the wild.
From Shutterstock

What should you do if you find injured wildlife?

1. Call your local wildlife care group for advice

Some animals aren’t actually injured, such as fledgling birds which are learning to fly, and others (such as goannas) can be dangerous, so be sure to seek advice before approaching wildlife. If you don’t know who your local wildlife care group is, type into a search engine “wildlife carer” to locate one near you.

2. Keep yourself safe

Armed with advice from a wildlife carer, ensure you don’t put yourself in a risky situation to rescue wildlife. Take care around busy roads, use a barrier between yourself and the injured animal (such as a towel or welding gloves) and avoid the bitey end! Wildlife are inherently fearful of people, which means they might attack if scared.




Read more:
Put out water for the wildlife in your garden on hot days


3. Secure the injured animal before transport

You don’t want an injured animal to escape in your car on the way to the vet. If the injured animal is a bird, small reptile or baby marsupial, a cardboard box with air holes and lined with a towel makes a good transport container. Don’t offer wildlife food, as they have very special diets and digestive systems.

4. Give as much information as possible

When you get to the vet, ensure you provide detailed information on where you found the animal. If the animal is healthy enough to enter wildlife rehabilitation, the wildlife carers will need to release the animal as close as possible to the location where it was found. This is because many animals, such as possums, are fiercely territorial and often die if relocated outside their territory.


Ultimately, many injured wild animals cannot be saved and will be euthanased after being dropped off at a veterinary clinic. This is not a bad outcome. Wildlife aren’t pets – they need to be fit to survive if they are ever going to have a chance in the wild. Injuries such as a badly broken wing or losing an eye would condemn wildlife upon release to starvation or predation.

It is much kinder to humanely euthanase injured wildlife which have no chance of survival rather than let them suffer a prolonged death in the wild. Even if the animal you drop off at the vet is ultimately euthansed, you have still saved it from prolonged suffering.The Conversation

Bronwyn Orr, Veterinarian and PhD candidate, University of Sydney

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

Comic explainer: forest giants house thousands of animals (so why do we keep cutting them down?)



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Wes Mountain/The Conversation, CC BY-ND

Madeleine De Gabriele, The Conversation and Wes Mountain, The Conversation

Giant eucalypts play an irreplaceable part in many of Australia’s ecosystems. These towering elders develop hollows, which make them nature’s high-rises, housing everything from endangered squirrel-gliders to lace monitors. Over 300 species of vertebrates in Australia depend on hollows in large old trees.

These “skyscraper trees” can take more than 190 years to grow big enough to play this nesting and denning role, yet developers are cutting them down at an astounding speed. In other places, such as Victoria’s Central Highlands Mountain Ash forests, the history of logging and fire mean that less than 1.2% of the original old-growth forest remains (that supports the highest density of large old hollow trees). And it’s not much better in other parts of our country.

David Lindenmayer explains how these trees form, the role they play – and how very hard they are to replace.




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Mountain ash has a regal presence: the tallest flowering plant in the world



Wes Mountain/The Conversation, CC BY-ND



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The plan to protect wildlife displaced by the Hume Highway has failed



Sign up to Beating Around the Bush, a series that profiles native plants: part gardening column, part dispatches from country, entirely Australian.The Conversation

Madeleine De Gabriele, Deputy Editor: Energy + Environment, The Conversation and Wes Mountain, Multimedia Editor, The Conversation

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

Elephants and economics: how to ensure we value wildlife properly



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Botswana’s elephants are officially an economic asset.
Ian Sewell/Wikimedia Commons, CC BY-SA

Michael Vardon, Australian National University; Carl Obst, University of Melbourne, and David Lindenmayer, Australian National University

Ensuring the economic health of nations is one of the biggest tasks expected of governments. The elephant in the room has long been the health of the environment, on which the health of the economy (and everything else) ultimately depends.

Most countries still rely on gross domestic product as the lead measure of their economic health. But this does not account for the loss of environmental condition. There is a growing recognition of the environmental damage that human activity causes, our dependence on a functioning environment, and the need for new approaches to measure and manage the world.

We hope this new idea can be advanced internationally at the two-week meeting of the Convention on Biological Diversity, which began this week in Sharm El-Sheikh, Egypt.




Read more:
Why we need environmental accounts alongside national accounts


Integrating the environment into national accounts has long been suggested as a way to improve information and has been tried in several countries.

In Botswana, where elephants are included in the nation’s environmental accounts, spending on wildlife conservation is now seen as an investment, rather than a cost. This example shows how integrating environmental assets into economic data can help provide a new policy framing for conservation. But worldwide, this type of “expanded accounting” has had limited impact on policy decisions so far.

On target

The Convention on Biological Diversity includes what are known as the Aichi Targets. Target 2 states:

By 2020, at the latest, biodiversity values have been integrated into national and local development and poverty reduction strategies and planning processes and are being incorporated into national accounting, as appropriate, and reporting systems. (emphasis added)

This provides a clear starting point for conservationists and economists to work together. So far, little has been done on the valuation of biodiversity, and the work that has been done so far has not progressed very far on the question of how to integrate environmental and economic values into national accounting.

On one hand, putting monetary values on biodiversity has been decried as the commodification of nature. But we argue that without using appropriately defined monetary values, the environment will always be vulnerable to economic forces. If Aichi Target 2 is to be met by 2020, we clearly need an agreed concept of biodiversity value, and a shared approach to recognising it.




Read more:
It pays to invest in biodiversity


Crucially, as well as calculating the environment’s contribution to the economy, we also need to assess the requirements for maintaining and enhancing biodiversity. To return to the example of Botswana’s elephants, this means recognising that elephants need land and water (Botswana’s wildlife consumes 10% of all its water, with elephants accounting for most use). As tourism-related industries generated roughly US$2 billion in 2013 (Botswana’s second-largest sector by revenue, with mining the first), the allocation of water and land to wildlife is clearly a prudent investment decision.

This approach can also reveal the impacts and trade-offs resulting from different land uses on environmental values. In Victoria’s Central Highlands, for example, the cessation of native logging would reduce revenue from timber production, but would also help support a range of rare and endangered species, including Leadbeater’s Possum. It would also benefit a range of other industries like agriculture, as well as the people in cities like Melbourne.




Read more:
Logging must stop in Melbourne’s biggest water supply catchment


Keeping the books up to date

Like any accounting system, these estimates of the economic value of the environment would need to be updated, ideally annually, if they are to remain relevant in underpinning governments’ decisions. This would also entail regular data collection on the species and ecosystems themselves.

Unfortunately, however, consistent long-term nationwide monitoring of biodiversity at the species or ecosystem level is rarely done. And while remote-sensing offers some promise for landscape-scale monitoring of major ecosystem types (such as tropical savannahs, temperate forests, wetlands), there is generally no substitute for boots on the ground.

This month’s summit in Egypt offers an opportunity for countries to reaffirm their recognition of the benefits that biodiversity provides to people and the economy. It also provides a chance to go further, to agree that integrated accounting will help us understand and appreciate the trade-offs between the environment and economy.

Recognising and accounting for the elephant in the room would be a great achievement – not to mention a sound investment in the future.


The authors would like to acknowledge the contribution of Heather Keith to this article.The Conversation

Michael Vardon, Associate Professor at the Fenner School, Australian National University; Carl Obst, Honorary Research Fellow, Melbourne Sustainable Society Institute, University of Melbourne, 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.

Curious Kids: How do plastic bags harm our environment and sea life?


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Sea turtle eating a plastic bag.
from www.shutterstock.com

Britta Denise Hardesty, CSIRO and Qamar Schuyler, CSIRO

This is an article from Curious Kids, a series for children. The Conversation is asking kids to send in questions they’d like an expert to answer. All questions are welcome – serious, weird or wacky! You might also like the podcast Imagine This, a co-production between ABC KIDS listen and The Conversation, based on Curious Kids.


My name is Sanuki and I’m 8 years old. I live in Melbourne. My question is how do plastic bags harm our environment and sea life? – Sanuki, age 8, Melbourne.


Good question, Sanuki!

Plastic bags harm marine (and land) environments in a few ways.

Turtles (and other animals) may mistake plastic bags for food. Turtles like to eat jellyfish, and we think turtles eat the plastic bags because they resemble jellyfish.

When turtles eat plastic, it can block their intestinal system (their guts). Therefore, they can no longer eat properly, which can kill them. The plastics in their tummy may also leak chemicals into the turtle. We don’t know whether this causes long term problems for the turtle, but it’s probably not good for them.




Read more:
Australian waters polluted by harmful tiny plastics


How plastic impacts the ecosystems

Plastic bags can also smother corals and other seabed communities. When plastic bags end up in our oceans, animals (including seals, dolphins and seabirds) can get tangled up in them. An animal with a plastic bag around its neck will have trouble moving through the water, catching its prey or feeding, and escaping predators.

Plastic can smother seabed and coral, impacting ecosystems.
from www.shutterstock.com

On land, plastic bags are an eyesore. They get stuck in trees, along fence lines, or as litter at our parks and beaches.

Many people don’t realise that plastic bags can also cause flooding. Previously in Ghana (in West Africa), plastic bags blocked storm water drains during a big rainstorm. This caused flooding so bad that people were killed.

Making plastic requires a lot of energy and work

Plastic bags can even be harmful before they are used. It takes a lot of resources and energy to create a plastic bag. A key ingredient is oil. As a fossil fuel, oil must be extracted from the ground. Do we want to use fossil fuel resources to make a product that is only used once (we call this a “single use plastic”)?

Many millions of barrels of oil are used to make plastic bags every year. A lot of energy is also used to make and transport plastic bags. It is better for the environment if we reduce our energy use.




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This South Pacific island of rubbish shows why we need to quit our plastic habit


The push towards plastic-free

Lately, lots of people recognise the impacts that plastic bags have, and they are working on alternatives. Many local and state governments have passed plastic bag bans here in Australia, which helps stop the use of single use plastic bags.

In fact, New South Wales is the only state in Australia where you can still get thin, single use plastic bags at the grocery store.

So, remind your parents to bring their reusable cloth bags whenever you go shopping. You just might save a turtle.


Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to us. They can:

* Email your question to curiouskids@theconversation.edu.au

* Tell us on Twitter


CC BY-ND

The ConversationPlease tell us your name, age and which city you live in. You can send an audio recording of your question too, if you want. Send as many questions as you like! We won’t be able to answer every question but we will do our best.

Britta Denise Hardesty, Principal Research Scientist, Oceans and Atmosphere Flagship, CSIRO and Qamar Schuyler, Research Scientist, Oceans and Atmospheres, CSIRO

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

A numbers game: killing rabbits to conserve native mammals



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Controlling rabbit populations has a key role in conserving Australia’s native plants and animals
William Booth

Euan Ritchie, Deakin University; Damien Fordham, University of Adelaide, and Miguel Lurgi, Centre national de la recherche scientifique (CNRS)

Invasive species have a devastating effect on biodiversity. In Australia, introduced red foxes and feral cats have been implicated in the majority of the extinctions of the native mammal fauna, which has been decimated since European arrival.

But there’s a herbivore that also causes eco-catastrophe. Rabbits both compete with native animals for food and shelter and act as easy prey for abundant populations of cats and foxes. By over-grazing vegetation and reducing habitat complexity, they make hunting easier for introduced predators.




Read more:
Invasive predators are eating the world’s animals to extinction – and the worst is close to home


Food webs are complex. Because of this, once an invasive species is embedded in a food web, simply eradicating them without considering the potential knock-on effects to other species they interact with, could cause unintended and undesirable consequences. We modelled different rates of rabbit population reduction to assess what level of control might be best for aiding the conservation of native mammals and not causing negative outcomes.

Rabbit numbers boom and crash

Rabbits, famously, reproduce rapidly and can cope with a relatively high predation rate. This can cause “hyper-predation”, where rabbit-inflated cat and fox populations indirectly increase the predation pressure on native mammals. This is especially so when rabbit populations intermittently crash due to, for example, extreme environmental events (like severe and prolonged droughts) or disease. This causes predators to switch their diet and eat more native mammals.

Threatened species such as the greater bilby are likely to benefit from rabbit control.
Jasmine Vink

This logically suggests that reducing rabbit numbers might thus help reduce cat and fox populations, by removing their abundant prey. Collectively this should benefit native plants and animals, including many threatened mammal species. However, ecosystem and pest management is a complex game.

When controlling rabbits we need to look beyond one or two species. We should consider the potential consequences for the entire ecological community, which ultimately depend on how changes in one species percolate through the network of ecological interactions between them.

Our new research, recently published in the Journal of Applied Ecology, set out to examine these questions in more detail. We consider other key players in Australia’s arid regions, such as kangaroos and dingoes, when looking at the effects of rabbit control on small native mammals. Our aim was to provide a better understanding of how changes in rabbit populations might affect other species via the food web.

We developed a multi-species ecological network model to describe and quantify how changing rabbit abundance can affect species on different feeding levels. In addition to rabbits, small native mammals, and mesopredators (cats and foxes), our model also considers apex predators (dingo) and large herbivores (kangaroo) as part of the Australian arid food web. This model allowed us to examine changes in predator-prey interactions (including potential prey switching and hyper-predation) and how these could affect the survival of native prey through time.

Our model of an Australian arid ecosystem food web.
Author provided

We found that removing rabbits at rates between 30-40% appeared to benefit small mammals. This is approximately the rate at which rabbits are currently managed in Australia using biocontrol agents (introduced diseases).

Rabbit control in Australia typically involves a “press and pulse” approach. Rabbit populations are suppressed via biocontrol (press) and periods of warren destruction and poisoning (pulse). Finding that reducing rabbit populations by around 40% seems most beneficial to small mammals is important, as it informs how and when we combine these strategies.

The 40% rate corresponds well with the disease-induced (press) mortality rate in rabbit populations due to rabbit haemorrhagic disease and myxomatosis. These are the primary biocontrol agents used in arid Australia to control rabbit populations.

Our study supports rabbit-reduction strategies that involve sustained “press” control, that kill a moderate portion of a rabbit population, with less frequent removal at higher proportions of the population.

To effectively manage invasive species, it’s important to focus on entire communities. Targeting single species might not be enough – every animal exists within a complex web of interactions.




Read more:
Mourn our lost mammals, while helping the survivors battle back


There has been much focus by the current government on controlling feral cats, as a way to conserve many of Australia’s unique and threatened mammal species.

The ConversationHowever, more focus could be devoted to protecting habitat cover and complexity, by reducing the land clearing and over-grazing that makes hunting easier. We can also manage rabbits sensibly to reduce competition for resources, and indirectly control cats and foxes.

Euan Ritchie, Associate Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University; Damien Fordham, , University of Adelaide, and Miguel Lurgi, Postdoctoral research fellow, Centre national de la recherche scientifique (CNRS)

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

Smart city planning can preserve old trees and the wildlife that needs them



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Mature trees have horizontal branches that are attractive to wildlife and birds.
from shutterstock.com

Philip Gibbons, Australian National University

Australia’s landscapes are dotted with mature eucalypts that were standing well before Captain Cook sailed into Botany Bay. These old trees were once revered as an icon of the unique Australian landscape, but they’re rapidly becoming collateral damage from population growth. Mature eucalypts are routinely removed to make way for new suburbs.

Good planning can ensure many more mature eucalypts are retained in urban developments.
Philip Gibbons

This has a considerable impact on our native fauna. Unless society is prepared to recognise the value of our pre-European eucalypts, urban growth will continue to irrevocably change our unique Australian landscape and the wildlife it supports.




Read more:
Trees are a city’s air conditioners, so why are we pulling them out?


Why are old eucalypts worth saving?

In urban landscapes, many consider large and old eucalypts a dangerous nuisance that drop limbs, crack footpaths and occupy space that could be used for housing. But when we remove these trees they are effectively lost forever. It takes at least 100-200 years before a eucalypt reaches ecological maturity.

Birds use old eucalypts as places to perch or nest.
Philip Gibbons

As trees mature, their branches become large and begin to grow horizontally rather than vertically, which is more attractive to many birds as perches and platforms where they can construct a nest.

Wildlife also use cavities inside ageing eucalypts. These are formed as the heartwood – the dead wood in the centre – decays. When a limb breaks it exposes cavities where the heartwood once occurred.

This is such a ubiquitous process in our forests that around 300 of Australia’s vertebrate species, such as possums, owls, ducks, parrots and bats, have evolved to use these cavities as exclusive places to roost or nest.

Mature trees also support high concentrations of food for animals that feed on nectar, such as honeyeaters, or seed, such as parrots.




Read more:
Concrete jungle? We’ll have to do more than plant trees to bring wildlife back to our cities


One study found that the number of native birds in an urban park or open space declines by half with the loss of every five mature eucalypts.

How can we keep old trees?

Decaying heartwood in older eucalypts leads to some large branches falling. This is when most eucalypts are removed from urban areas. So we remove trees at the exact point in time when they become more attractive to wildlife.

Plantings around the base of a mature eucalypt discourage pedestrian traffic or parked cars.
Philip Gibbons

A well-trained arborist knows that old — or even dead — eucalypts don’t need to be removed to make them safe. A tree is only dangerous if it has what arborists call a target. Unless there is a path, road or structure under a tree, then the probability of something or someone being struck by a falling branch is often below the threshold of acceptable risk.

Progressive arborists first focus on eliminating targets. For example, they might plant shrubs around the base of dead or rapidly ageing trees to minimise pedestrian traffic, rather than eliminating trees.

Where targets can’t be managed, trimming trees can remove branches that have a high risk of falling. Trees can also be structurally supported (braced) to remain stable. Such trees remain suitable as habitat for many native species.

Developers can plan around old trees.
from shutterstock.com

How to design around trees

The removal of mature eucalypts is, in part, due to urban developers not considering these trees early in the planning process.

I have worked with one developer on the outskirts of Canberra to identify important trees. The developer then planned around, rather than in spite of, these trees.

The outcome has been around 80% of mature trees have been retained. This is much greater than the proportion of mature trees retained in other new urban developments in Canberra.




Read more:
Trees versus light rail: we need to rethink skewed urban planning values


The ConversationAustralia’s population is projected to double in 50 years, so our suburbs will continue to infill and expand. This will result in the continued loss of our mature eucalypts unless our approach to planning changes.

Philip Gibbons, Associate professor, Australian National University

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