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Stunning new lows in cost of large scale solar and battery storage
Ausnet, and the case for a rethink on who pays for new grid connections
How clean are Australia’s ‘clean coal’ power stations?
Trump’s clean energy budget cuts would ‘devastate’ emerging economic sector
Coalition seeks applications for solar thermal funds by end of year
SunPower Breaks Ground on 28-Megawatt Solar Power System at Vandenberg Air Force Base
Flamingo balancing act saves energy
Germany to host two more battery factories
Curious Kids: If a huge huntsman spider is sucked into a vacuum cleaner, can it crawl out later?
![](https://cdn.theconversation.com/files/168490/width496/file-20170509-20761-1b1xkf5.jpg)
This is an article from Curious Kids, a new 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!
If a huge huntsman spider is sucked into a vacuum cleaner, can it crawl out later? I really, really need to know. – Lucy, age 8, Ivanhoe.
Editor’s note: for such an important question, we consulted two experts – a vacuum cleaner design expert and a spider expert.
Simon Lockrey, industrial design research fellow and former vacuum cleaner design engineer: It certainly could, depending on the vacuum cleaner.
If there is a clear way out, the huntsman could make its escape when the vacuum is turned off. That’s assuming the spider survived being sucked up, that there were surfaces it could stick to, and there were gaps big enough to squeeze through.
However, sometimes escape is not possible. This is because some vacuum cleaners have internal “doors” that only open on the way in, and not the way out. Think of a trap door that only opens one way! We had those in some of the vacuums I helped to design.
Not all vacuums have this feature. It is mainly for machines that have short openings and get tipped up a lot, such as hand-held vacuums. So without that one-way door, a spider may have a chance to escape.
But the big question is whether a spider would even survive being sucked into a vacuum cleaner at all. Put it this way: when a spider enters a high-speed cyclonic machine, it may be travelling super quick. Speeds vary depending on the model. However, there are new digital motors that can rotate five times quicker than a Formula 1 engine – that’s 120,000 revolutions per minute!
Probably a spider’s best bet would be to lay low until the vacuum cleaner is emptied, and then make a getaway from the bin it is emptied into.
Maggie Hardy, spider expert: When a spider is sucked up by a vacuum cleaner, it first needs to avoid being killed by the low pressure that sucks air and dirt into the vacuum. And second, the spider will have to heal from any damage (scratches, or even lost legs) caused by travelling through the brushes, hoses and chambers inside the vacuum cleaner.
We know spiders can survive in low pressure (like you find in a vacuum) and in low gravity, thanks to some research carried out in space by NASA.
The very first spiders in space were sent for an experiment designed by an American high school student named Judith Miles, in 1973. She wanted to find out how the “spidernauts” would respond to weightlessness in low gravity, because spiders on Earth use both wind and gravity to properly construct their webs. Two more spidernaut experiments were conducted on the International Space Station in 2008 and 2009, and you can compare the results you get on Earth with what the astronauts found in space.
Spiders in space.The most recent study, in 2011, found that with some practice spidernauts build webs that are very similar to the ones spiders build on Earth.
Spiders have an exoskeleton (their skeleton is on the outside of their body). Spider movement depends on them being able to inflate and deflate their legs, so if they lose a leg sometimes there isn’t enough pressure for them to move their legs. If a spider loses one or more of its legs it will usually regrow them in the next moult (the next time they shed their exoskeleton).
Spiders are a delightful and important part of the natural world, and if they are in your house they are generally lost.
You can build your own spider hospital, in case you do find an injured spider in or around your home. Of course, first you should check with an adult or an expert to make sure the spider isn’t dangerous, and never pick up a spider with your hands – have an adult use a large piece of cardboard, or a plastic container.
How to make a spider hospital.Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to us. You can:
* Email your question to curiouskids@theconversation.edu.au
* Tell us on Twitter by tagging @ConversationEDU with the hashtag #curiouskids, or
* Tell us on Facebook
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Please 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.
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Simon Lockrey worked for Dyson as a design engineer from 2007-2009. He has not received any funding from Dyson in his subsequent academic role at RMIT. He does receive funding from various government, NFP/ NGO, and industry partners for research on sustainability, innovation and design.
Maggie Hardy has received funding from The University of Queensland and UniQuest Pty Ltd.
Widespread invasive species control is a risky business
![](https://cdn.theconversation.com/files/170482/width496/file-20170523-8917-14t8me9.jpg)
In 1977, on the islands of French Polynesia, government authorities released a predatory snail. They hoped this introduction would effectively control another species of invasive snail, previously introduced to supply escargot.
Instead, by the early 1980s, scientists reported alarming declines of native snail populations. Within ten years, 48 native snail species (genus Partula) had been driven to extinction in the wild.
The extinction of the Partula is notorious partially because these snails were, before going extinct, the study subjects of the first test in nature of Darwin’s theory of evolution by natural selection.
In the decades since, attempts to control and eradicate invasive species have become common, generally with far better results.
However, our paper, published today in Nature Ecology and Evolution, highlights the importance of scientific evidence and independent assessments when deciding whether to control or eradicate invasive species.
From islands to continentsIncreasingly, large-scale invasive species control initiatives are being proposed worldwide. As early as 2018, a herpes virus will be released in Australia’s largest river system, targeting invasive common carp. As part of its Threatened Species Strategy, Australia is also planning to kill two million feral cats.
Across the Tasman Sea, New Zealand has made a bold commitment to remove three groups of invasive predators entirely by 2050.
![](https://cdn.theconversation.com/files/170494/width754/file-20170523-8876-1yyy3dn.jpg)
It’s not just Australians and Kiwis making ambitious invasive species control proposals: bounties are being paid to catch invasive fish in the United States. The European Union has blacklisted 37 species of plants and animals within 4 million square kilometres, many of which are well-established and will be targeted by control (not preventative) measures.
Meanwhile, new gene editing technology has made the continental-scale eradication of invasive species a real possibility, for example by implementing gene drives that reduce breeding success. If you haven’t heard of it, CRISPR is a startling new biotechnology that makes genetic modification of plants and animals much easier. It offers new potential solutions to some of the world’s worst environmental, agricultural and human health problems.
These schemes will be implemented across large and complex social-ecological systems, and some options – like releasing a virus or genetically engineered species – may be irreversible.
Managing riskWhile these projects may yield great benefits, we must be aware of the potential risk of unexpected and undesirable outcomes.
A prime example is the project to remove invasive carp from a million square kilometres of Australia’s rivers. Some scientists have expressed concern about the potential for the virus to jump species, and the effects of having hundreds of tonnes of dead fish fouling waterways and sapping oxygen from the water. The CSIRO and those planning the release of the virus suggest it is safe and effective.
Despite extensive media reporting giving the impression that the plan is approved to go ahead, the National Carp Control Plan has yet to publish a risk assessment, and is planning to deliver a report in 2018.
Removing well-established invasive species can create unforeseen consequences. These species can play significant roles in food webs, provide shelter for native animals, support ecosystem services, and their sudden death can disrupt ecological processes that are important to native species.
For example, a large amount of time and effort was spent in removing the non-native tamarix (or “salt cedar”) in the southwestern United States, because of the belief it was harming the water table.
Yet, subsequent research has indicated that the negative effects of tamarix have been exaggerated. In some areas, the plant is actually used by large numbers of endangered flycatchers to nest and fledge their young.
![](https://cdn.theconversation.com/files/170478/width754/file-20170523-8883-1cjatd8.jpg)
In our paper, we highlight a series of considerations that should be addressed before plunging into large-scale invasive species control.
Fundamentally, there must be a demonstrable ecological and social benefit from control or eradication, above and beyond the purely ideological. At first this might seem facile, but invasive species control initiatives are often highly politicised, with science taking a back seat. Given scarce funding for conservation, it is crucial that resources are not squandered on programmes that may not deliver - or could cause environmental damage.
We must avoid assuming that attempting to control invasive species will, by default, solve our environmental problems. This means addressing the full range of human pressures which negatively affect biodiversity. We must also consider how removing an influential invasive species could benefit other invasive species, harm native species through increased predation and competition, or alter ecological processes or habitat.
Comprehensive risk-benefit assessment of invasive species control programs allow decision-makers to proactively avoid, manage or accept these risks.
For example, tonnes of decomposing carp post-virus may cause short-term water quality issues, or the death of native species. Ultimately, however, these risks could be acceptable if the virus is effective, and allows native species a window of opportunity to recover.
Large-scale invasive species control demands careful investigation of the risks and rewards. We hope our paper can provide policy-makers with better guidelines for science-based decision-making.
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R. Keller Kopf has applied for funding from the Fisheries Research and Development Corporation to assess the: Ecological, Social and Socio-Economic Risks of Releasing Koi Herpes Virus to Control Common Carp in Australia.
Dale Nimmo receives funding from the Australian Research Council, the Australian Academy of Science, the Hermon Slade Foundation, the Department of Parks and Wildlife, and the Department of Land, Water and Planning.
Paul Humphries receives funding from the MDBA Environmental Water Knowledge and Research Program and has received funding from the MDBA Native Fish Strategy. He is a collaborator on an application for funding from the Fisheries Research and Development Corporation in relation to the Koi Herpes Virus to Control Common Carp in Australia..
Thinking big gives top predators the competitive edge
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Dingoes could be the key to controlling red foxes and other invasive predators, but only if we encourage them in large enough numbers over a wide enough area, our research shows.
Interest in re-introducing or restoring top predators, like dingoes and wolves, has been fuelled by recent studies demonstrating their important roles in their ecosystems. They can especially be vital in suppressing the abundance of lower-order competitors or “mesopredators”, like red foxes and possibly feral cats (which can have devastating effects on native species).
But researchers have found top predators aren’t always successful in reducing mesopredator numbers. Until now, such variation has been linked to human presence, land-use changes and environmental factors such as landscape productivity.
However, our research, published yesterday in Nature Communications, found that a key factor for success is high numbers of dingoes and wolves across their natural range.
The density effectIf you look at how species are typically distributed across a landscape – their range – ecological theory predicts there’ll be lower numbers at the outer edges of their range.
If you do need large numbers of top predators to effectively suppress mesopredators, the core of their range is potentially the best place to look.
We tested this idea, looking at the dingo in Australia and the grey wolf in North America and Europe. The mesopredators included the red fox in Australia, the coyote in North America and the golden jackal in Europe.
![](https://cdn.theconversation.com/files/170446/width754/file-20170522-7379-r7mxz4.jpg)
We used information from bounty hunting programs, as these provide data on predator numbers across a wide geographical area. In the case of Australia we used historic data from the 1950s, as this is the most recent reliable information about red fox and dingo distribution. The actual population numbers of red foxes and dingoes have changed substantially since then, but the nature of their interactions – which is what we were investigating – has not.
We determined that top predators exist in higher numbers at the core of their ranges in comparison to the edges. We then looked at mesopredator numbers across the range edges of their respective top predator.
![](https://cdn.theconversation.com/files/170448/width754/file-20170522-7358-lmaea2.jpg)
The results, which were consistent across the three continents, suggest that top predators can suppress mesopredators effectively (even completely) but only in the core of their geographic range, where their numbers are highest.
In other words, abundant top predators can exert disproportionate mesopredator control once their numbers increase past a certain point.
![](https://cdn.theconversation.com/files/170449/width754/file-20170522-7364-1nc7xvl.jpg)
The relationship we uncovered is now formalised as the “Enemy Constraint Hypothesis”. It could apply to other predator dyads, where two animals compete for similar resources – even relationships involving parasites and pathogens.
Our findings are important for understanding species interactions and niches, as well as the ecological role of top predators. It could explain why other studies have found top predators have little influence on mesopredators: they were looking at the edge, not the core, of the top predators’ range.
![](https://cdn.theconversation.com/files/170451/width754/file-20170522-7351-t7e168.jpg)
Dingoes can be vital for reducing red fox and possibly feral cat numbers. In our case studies the ranges of each top predator were limited primarily by human use of the land and intensive shooting, trapping and poisoning.
Killing pack animals like dingoes can fracture social groups, potentially altering their natural behaviour and interactions with other species. Future studies on predator interactions therefore need to consider the extent to which the animals are acting in response to human intervention.
If we want to benefit from the presence of top predators, we need to rethink our approach to management – especially where they are subjected to broad-scale control, as the dingo is in some parts of Australia.
Changing our relationship with top predators would not come without its challenges, but high extinction rates around the world (and especially in Australia) clearly indicate that we urgently need to change something. If this includes restoring top predators, then we need to think big.
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Thomas Newsome receives funding from Deakin University, The University of Sydney, the National Geographic Society for Research and Exploration, Seattle City Lights, Washington Department of Fish and Wildlife, and Newmont Tanami Operations. He is Treasurer of the Australasian Wildlife Management Society and a member of the Australian Mammal Society and the Ecological Society of Australia.
More people heading to court to spur action on climate change, study finds
- Study by UN and Columbia finds ‘proliferation’ of cases instigated by citizens
- Lion’s share of court cases are in US but number also growing around the world
Governments around the world are increasingly being challenged in court to do more to combat the threat of climate change, with litigation ranging from a group’s attempt to stop an airport runway in Austria to a Pakistani farmer suing his government over its failure to adapt to rising temperatures, a new study has found.
Related: Trump treading water over climate change deal, says deputy UN chief
Continue reading...How plastic took over the world in 50 years | Letters
Is anyone cheered by your report of the extent and intensity of plastic pollution (38 million pieces of plastic waste found on uninhabited South Pacific island, 16 May)? The plastics industry, perhaps? It is, after all, a sign of how much they have changed the world. I recall my first encounter with a transparent plastic bottle, 50 years ago this year. I also recall the “information” films, sponsored by firms such as BP and Shell, and widely shown in schools at the time, extolling the benefits that plastic brings. The industry put petroleum byproducts to good use. It was cheap. It was scientific. It was new. It was innovation. Today, the ideology of innovation is every bit as powerful. The future, we are told, belongs to the “disruptive innovators” – Uber and their ilk. They make billions, but neither political nor economic systems have evolved ways of dealing with or costing the havoc they cause. Plastic was the disruptive technology of its day: half a century later, we know the mess will never be cleared up. We also know that those – animal and vegetable – who pay the price will not be those who squirrelled away the profits. It is time society found a way of holding innovation and innovators to account.
Professor John Holford
Nottingham
• In your article, the plight of Henderson Island shows very visually the direct impact people are having on nature – even in the places that we consider to be most special. As a Unesco world heritage site, the island is considered to have outstanding universal value, but despite their protected status, nearly half of natural world heritage sites are facing serious threats, from poaching and illegal fishing to harmful industrial activity. Urgent action needs to be taken to protect these precious areas, which is why WWF has launched a global campaign, Together, Saving Our Shared Heritage, to safeguard these sites. The threats to our planet are now so great that wildlife populations are disappearing at an alarming rate. Current predictions are that wildlife numbers will have declined by 67% between the 1970s and the end of this decade unless urgent action is taken. We are all responsible for the future of our planet.
Chris Gee
Head of campaigns, WWF-UK
How many Teslas does it take to black out an apartment block?
'My worst nightmares are coming true': Europe's last primeval forest on 'brink of collapse'
Polish government is accused of pushing Białowieża forest ecosystem to point of no return with state-sanctioned logging in Unesco world heritage site
Scientists and environmental campaigners have accused the Polish government of bringing the ecosystem of the Białowieża forest in north-eastern Poland to the “brink of collapse”, one year after a revised forest management plan permitted the trebling of state logging activity and removed a ban on logging in old growth areas.
Large parts of the forest, which spans Poland’s eastern border with Belarus and contains some of Europe’s last remaining primeval woodland, are subject to natural processes not disturbed by direct human intervention.
Continue reading...UK bathing water ranks next from last in EU beach table
20 sites fail safe bathing criteria stoking fears UK will once more be ‘dirty man of Europe’ after Brexit
The UK is second bottom in a league table ranking EU countries on the quality of their bathing water, stoking fears that the “dirty man of Europe” could be on his way home after Brexit.
96.4% of British beaches were found safe to swim in last year, but 20 sites failed the assessment in the annual survey by the European Environmental Agency (EEA) released on Tuesday. Only Ireland had a higher percentage of poor quality bathing waters at 4%.
Continue reading...Australian Conservation Foundation vows to pursue all avenues to stop Adani loan
Environmental group warns it will take legal action against Northern Australia Infrastructure Facility directors if funding granted for rail line
The Australian Conservation Foundation has warned it will pursue all avenues, including possible legal action, to stop a concessional loan being granted to a rail line associated with the controversial Adani coalmine.
The ACF’s president, prominent businessman Geoff Cousins, told Guardian Australia on Tuesday the environmental group would “pursue [directors of the Northern Australia Infrastructure Facility (Naif)] through whatever means possible” in the event the Naif granted the rail project a loan.
Continue reading...Tourmalet to tarte aux pommes: savouring the French Pyrenees by bike
If Tour De France climbs without time pressure or panniers sounds appealing, investigate this bespoke cycling holiday in the French Pyrenees
What kind of cyclist are you? A superfit obsessive with high-end equipment, up for the toughest races? Or a potterer along county lanes, limiting yourself to 20 miles a day, treating cycling as a gentle route to the next pub? If you’re somewhere in between – but fitness can vary considerably, because you are time-poor – then this trip could be for you.
Perhaps you also want to taste Europe’s finest cycling, tackle the Tourmalet, or other classic cols, but don’t want to carry panniers, or worry about bike repairs, agonise over routes or scour websites for the best-value restaurants and hotels. You want to enjoy cycling as a pure, challenging experience, but go at your own pace, stop for lunch, take photographs, and feel that you can have that extra glass of wine at the end of the day.
Continue reading...The Great British Bee Count – in pictures
Up to 15,000 people took part in the 2016 Great British Bee Count, recording 383,759 bees, some of which are pictured here. This year’s annual count has begun and will run until 30 June 2017
- Download the free app to help monitor and learn more about the endangered bee population and get tips for bee-friendly planting
Trump treading water over climate change deal, says deputy UN chief
Amina Mohammed says president seems to be avoiding making decision on whether US will renege on historic agreement
The UN’s deputy secretary general has accused President Donald Trump of “treading water” over a decision on the future of the Paris climate change agreement, on which the fate of millions of people depend.
Amina Mohammed told the Guardian she was hopeful the US would not renege on the deal signed last year, but that Trump appeared to be avoiding a public declaration after taking such a hard line during his campaign for the White House.
Continue reading...