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Direct Action carbon reduction policy running out of steam
With 83% of the fund spent, the government’s central climate policy is almost exhausted, with no further funding committed
The federal government’s Direct Action carbon reduction policy appears to be running out of steam, with participation from industry dropping, the cost of the program rising and the budget for emissions reduction nearly exhausted.
The Clean Energy Regulator announced on Thursday it would pay a further $367m to polluting industries, in return for a commitment for them to reduce carbon emissions by 34.4m tonnes.
Continue reading...Leaves nearing their end still fly the flag
Sandy Bedfordshire The sycamore’s leaves, free to swing in the gappy canopy, seem to dance in a soundless jig
In the past fortnight, winter has descended into the branches of a big sycamore tree. As if they were the hangers-on at a party, a scattering of leaves are still flying the flag, wearing ready-to-drop yellow. Liberated from the constrictions and crowding of their erstwhile neighbours, they are free to swing in the gappy canopy. As the breeze lifts, they are raised up as one into a rocksteady beat.
Never have the leaves looked so alive as when so close to death. The great pointy-edged plates are picked up wonderfully by the wind as with no other tree around, and seem to dance in a soundless jig.
Continue reading...Bright city lights are keeping ocean predators awake and hungry
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Light pollution is changing the day-night cycle of some fish, dramatically affecting their feeding behaviour, according to our recently published study.
In one of the first studies of its kind, we found that increased light levels in marine habitats, associated with large coastal cities, can significantly change predator-prey dynamics.
We used a combination of underwater video and sonar to spy on these communities and record how their behaviour changed. Like us, the animals in our study slowed down at night. Predatory fish became sluggish and had little appetite.
But when the lights went on some of these same predators disappeared, while others feasted on the well-lit underwater buffet. Overall, there was much greater predation on seafloor-dwelling communities when the night waters were lit.
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The dark blanket of night might once have heralded time to rest, but the great pace of human activity has required that nights get shorter and days become artificially longer.
As the sun sets, streetlights flicker to life, generators go into overdrive and the landscape becomes dotted with artificial light, producing some of the most spectacular images from space. The sky glow from major urban centres can be seen more than 300km away.
While this may have enhanced productivity, we are starting to realise that the ecological effects on animals that have evolved under natural day–night cycles are significant.
Artificial lighting of outdoor areas began in earnest in the late 1700s. We have been manipulating lighting regimes for centuries for purposes that include increased egg production in hens and to encourage birds to sing during winter.
However, we have only recently begun to investigate the damaging ecological consequences. We now know that lighting used on offshore energy installations causes increased deaths of migratory birds and beach lighting can cause turtle hatchlings to become disoriented and reduce the chances of a safe journey from nest to sea.
But these are the more obvious impacts of a disrupted day length. More subtle changes in animal behaviours caused by artificial lighting have yet to be illuminated (pun intended!).
Lights, camera, predationUsing LED spotlights, we manipulated the light patterns underneath a wharf in Sydney Harbour, illuminating sessile (attached to the seafloor and wharf) invertebrate prey communities to fish predators. We recorded fish numbers and behaviour under different lighting scenarios (day, night and artificially lit night), and the prey communities were either protected or exposed to predators.
Despite different changes in different species, overall we found that more animals were getting eaten. The main predators were yellowfin bream (Acanthopagrus australis) and leatherjackets (Monocanthidae). The prey being consumed included barnacles, bryozoans (encrusting and arborescent), ascidians (solitary and colonial), sponges and bivalves.
Large predators are very important in ecosystems and play a major role in the structure of the whole food chain. If these predators are removed from the system, there are cascading effects and sometimes entire ecosystems collapse.
So we should expect that changes to the behaviour of predators will have major consequences for prey communities. When we turned on the lights, we found prey communities changed to more closely resemble communities exposed to predation during the day. This increase in predation pressure highlights the effect prey communities face under a brightening future, possibly leading to shifts in prey structure with flow-on effects to ecosystem functioning.
A bright futureAbout 70% of the world’s largest cities are situated on the coast, and there has been a corresponding increase in urban lighting that also illuminates the underwater world.
When coupled with the chemical pollution and increasing noise that our urban activities are introducing into waterways, the outlook is harsh for our marine life.
We are beginning to understand the effects of artificial light on the natural world around us, but there is still a long way to go – especially in the underwater realm. World populations continue to grow and increasing pressure is placed on our coastal fringes to support this growth, so we need to find solutions to reduce our impact wherever we can.
One solution for light pollution is to control the wavelength of light used depending on the location of the lights. LEDs are increasingly being used because they are effective and cheap to run, but they emit a broad spectrum with peaks in blue and green wavelengths, which penetrate to great depths underwater. Moving towards other spectra, such as red which doesn’t penetrate as far, could reduce the problem.
Ultimately, while our requirement for artificial light at night is unlikely to diminish, darkness remains a necessary component of many animal’s lives. We must do our best to bring back their night.
![The Conversation](https://counter.theconversation.edu.au/content/68965/count.gif)
Damon Bolton receives funding from UNSW.
Alistair Becker receives funding from the NSW Recreational Fishing Trust
Emma Johnston receives funding from the Australian Research Council.
Graeme Clark receives funding from UNSW, SCAR.
Katherine Dafforn receives funding from the Australian Research Council. She is affiliated with the Sydney Institute of Marine Science.
Mariana Mayer-Pinto receives funding from UNSW.
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The key to future food supply is sitting on our cities' doorsteps
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Our food systems are under increasing pressure from growing populations, diminishing resources and climate change. But, in a new report, we argue that city foodbowls – the agricultural land surrounding our cities – could supply more secure and sustainable food.
The final report of our Foodprint Melbourne project outlines a vision for “resilient city foodbowls” that can harness city waste to produce food, reduce dependence on distant sources of food and act as a buffer against increasing volatility in global food supplies.
But to do so we need to start planning now. Food is a basic human need – along with water, housing and transport – but it hasn’t been high on the planning agenda for Australia’s cities.
Growing food, and jobsAustralia’s city foodbowls are an important part of the nation’s food supply, particularly for fresh vegetables.
Melbourne’s foodbowl produces almost half of the vegetables grown in Victoria, and has the capacity to meet around 82% of the city’s vegetable needs.
Nationally, around 47% of highly perishable vegetables (such as lettuce, tomatoes and mushrooms) are produced in the foodbowls of the major state capitals, as well as eggs, chicken and perishable fruits such as berries.
New analysis by Deloitte Access Economics has shown that Melbourne’s foodbowl contributes A$2.45 billion each year to the regional economy and around 21,000 fulltime-equivalent jobs. The largest contributors (to the economy and to jobs) in Melbourne’s foodbowl are the fruit and vegetable industries.
Other research estimates that agriculture in Sydney’s foodbowl contributes around A$1 billion to the regional economy. The flow-on effects through the regional economy are estimated to be considerably higher.
City foodbowls at riskCity foodbowls are increasingly at risk. Our project has previously highlighted risks from urban sprawl, climate change, water scarcity and high levels of food waste.
Melbourne’s foodbowl currently supplies 41% of the city’s total food needs. But growing population and less land means this could fall to 18% by 2050.
Australia’s other city foodbowls face similar pressures. For example, between 2000 and 2005, Brisbane’s land available for vegetable crops reduced by 28%, and Sydney may lose 90% of its vegetable-growing land by 2031 if its current growth rate continues.
These losses can be minimised by setting strong limits on urban sprawl, using existing residential areas (infill) and encouraging higher-density living.
However, accommodating a future Melbourne population of 7 million (even at much higher density) will still likely mean we lose some farmland. The Deloitte modelling estimated this will lead to a loss of agricultural output from Melbourne’s foodbowl of between A$32 million and A$111 million each year.
Protecting our food supplyAustralia’s city foodbowls could play a vital role in a more sustainable and resilient food supply. If we look after our foodbowls, these areas will strengthen cities against the disruptions in food supplies that are likely to become more common thanks to climate change.
The New Urban Agenda adopted in October 2016 at the United Nations Conference on Housing and Sustainable Urban Development, or Habitat III, emphasises the need for cities to “strengthen food system planning”. It recognises that dependence on distant sources of food and other resources can create sustainability challenges and vulnerabilities to supply disruptions.
Resilient city food systems will need to draw on food from multiple sources – global, national and local – to be able to withstand and recover from supply disruptions due to chronic stresses, such as drought, and acute shocks, such as storms and floods.
Our final report presents a vision of a resilient city foodbowl for Melbourne.
In this future vision, highly perishable foods continue to grow close to the city. City waste streams are harnessed to counter decreasing supplies of water and conventional fertilisers, and increased investment in delivery of recycled water creates “drought-proof” areas of food production close to city water treatment plants.
If Australia’s cities are to retain their foodbowls as they grow, food will need to become a central focus of city planning. This is likely to require new policy approaches focused on “food system planning” that addresses land use and other issues, such as water availability.
We also need to strengthen local and regional food systems by finding innovative ways to link city fringe farmers and urban consumers – such as food hubs. This will create more diverse and resilient supply chains.
![The Conversation](https://counter.theconversation.edu.au/content/69146/count.gif)
Rachel Carey is a Research Fellow at the University of Melbourne on the Foodprint Melbourne project, which is funded by the Lord Mayor's Charitable Foundation. Project partners include the City of Melbourne and the peak bodies representing the local government areas in Melbourne's city fringe foodbowl. She is also a Research Fellow on the project 'Regulating Food Labels: The case of free range food products in Australia', which is funded by the Australian Research Council.
Jennifer Sheridan is a researcher at the University of Melbourne on the Foodprint Melbourne project, which is funded by the Lord Mayor's Charitable Foundation. Project partners include the City of Melbourne and the peak bodies representing the local government areas in Melbourne's city fringe foodbowl.
Kirsten Larsen is a Research Fellow at the University of Melbourne on the Foodprint Melbourne project, which is funded by the Lord Mayor's Charitable Foundation. Project partners include the City of Melbourne and the peak bodies representing the local government areas in Melbourne's city fringe foodbowl. She is also a Director of the Open Food Foundation, which receives money from the Victorian Department of Health.
There are 14 wild orange-bellied parrots left – this summer is our last chance to save them
When only 14 of any species are left in the wild, you know they are in trouble.
Such is the crisis faced by the last remaining population of orange-bellied parrots in southwest Tasmania. To make matters even worse, very few of these birds are females.
On our trip to southwest Tasmania on Tuesday, we found four nests. We will be returning to the site soon to count the fertile eggs.
There have been some heartening stories of the reversal of fortunes when endangered species crash to such low levels, but these stand against a bleak backdrop of increasing extinction rates in the 21st century.
In perhaps the most dramatic success story, there were only five Chatham Island black robins left in 1980, with the survival of the species hinging on just one breeding pair. The outlook was bleak, but a dedicated team of New Zealand scientists took the daring step of cross-fostering eggs and young to another species to boost productivity.
The fostering program developed to save the black robin worked so well that it became the benchmark for how to save endangered birds around the world. There are now more than 200 Chatham Island black robins in the wild.
Orange-bellied parrots have an awkward habit that makes them an especially difficult bird to conserve: they migrate.
Every autumn the parrots leave their breeding grounds in Tasmania and fly across Bass Strait to spend the winter in the salt marshes along the Victorian coastline. Migration is a dangerous business and many do not return.
Parrots often move around in flocks looking for food. Knowing where to go, and when, is cultural knowledge held in trust by the flock. Older, experienced birds lead the younger ones and share their knowledge of vast landscapes. This transfer of information from parents to offspring, and between all flock members, is essential.
When numbers fall and birds cannot draw on that reservoir of knowledge, or indeed benefit from the safety of numbers, things begin to go wrong.
Numbers are now so low that it is doubtful whether enough experienced parrots are left to lead the flock to food and safety. The value of the remaining wild birds is especially high.
Several years ago the Tasmanian government showed tremendous foresight by setting up a captive breeding colony of orange-bellied parrots. These were the “insurance population” for gradual release into the wild to bolster the critical mass of wild birds.
However, the captive-raised parrots have not proved to be as hardy as their wild cousins. Numbers in the wild continue to dwindle in spite of several decades of bird releases at the breeding site. A major outbreak of parrot beak and feather disease in 2015 also wiped out many of the nestlings hatched by wild parrots.
With only 14 wild birds left, difficult decisions must be made and dramatic action is required. The “insurance population” remains our trump card.
We recently launched a crowd-funding campaign to cover the costs of an emergency intervention using the insurance population.
The extent of the crisis only washed over us about a week ago. But hamstrung by the slowness of raising funding via usual methods, and with the agreement of all parties involved, we decided to raise funds quickly to enable the required emergency actions.
We reached our initial target of A$60,000 in less than two days. As we write, we are crashing through the A$100,000 mark in pledges from concerned members of the public. We have just lifted the bar to A$120,000 to fund our work well into next year.
We feel truly humbled by the generosity of the public reaction. It shows the extent to which people from all walks of life care about saving this species from extinction.
Our immediate plans are simple by necessity. As the few remaining orange-bellied parrots have already laid their clutches, we have little time to act if we are to help them breed to full capacity this season.
We will closely monitor the breeding birds and wherever necessary replace any infertile eggs with fertile ones from the captive birds. We will bolster with eggs and nestlings the brood of any female who has too few, and we will remove and hand-rear back to full health any nestlings that appear to be ailing. We will also boost the number of female nestlings to try to overcome the imbalance of the sexes.
In short, we will use the precious insurance birds in the best way possible, by turning their young into fully wild birds, who are fighting fit thanks to close bonds with their wild foster parents.
It will be a long road to recovery and there are no guarantees of success. But we simply cannot let these beautiful birds go extinct without joining the courageous team who have nurtured them this far and throwing absolutely everything we have at getting them back on their feet (or on the wing) in the wild.
![The Conversation](https://counter.theconversation.edu.au/content/69274/count.gif)
Rob Heinsohn receives funding from the Threatened Species Hub (Australian Federal Government) and the Australian Research Council.
Dejan Stojanovic receives funding from the Australian Government as part of a Research Offset, the Australian Research Council, and the National Environmental Science Program.
A poor choice of words to describe rich people | Brief letters
If we are not recycling all our plastic waste, largely because many councils cannot deal with all the variations (Just a third of plastic is recycled, survey shows, 22 November), why are the major supermarkets allowed to keep inventing new wrappings consisting of mixed materials and marked “Not currently recyclable”?
Jean Wood
Hythe, Kent
• In 1970, it wasn’t the work, it was the prospect of sex, drugs and rock’n’roll and escaping from home that was the lure (Our friends from the north, G2, 22 November). Now I crave to return to Liverpool, but London-born husband refuses to go somewhere that’s wetter and colder.
Jennifer Henley
London
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Air pollution 'causes 467,000 premature deaths a year in Europe'
Drive, baby, drive: Hammond's autumn statement is more grey than green
The money for new roads and freezing fuel tax overwhelms support for electric cars, further fuelling the nation’s air pollution crisis
Drive, baby, drive - that was the message from chancellor Philip Hammond’s autumn budget statement, with more money paving the way to new roads and a freeze on fuel tax.
The problem is the UK already has an air pollution crisis that causes tens of thousands of early deaths – more traffic will only make it worse. Furthermore, rising transport emissions are one of the biggest obstacles to the nation meeting its legal targets for cutting carbon emissions.
Continue reading...Schiaparelli: Esa gives update on Mars crash investigation
Autumn colors across North America – in pictures
As winter finally arrives across the US, we take a look back at the annual dazzling display of color across the continent
Continue reading...