How did our galaxy form? How do galaxies evolve over time? Where did the Sun’s lost siblings end up?
Three hours north-east of Parkes lies a remote astronomical research facility, unpolluted by city lights, where researchers are collecting vast amounts of data in an effort to unlock some of the biggest questions about our Universe.
Siding Spring Observatory, or SSO, is one of Australia’s top sites for astronomical research. You’ve probably heard of the Parkes telescope, made famous by the movie The Dish, but SSO is also a key character in Australia’s space research story.
In this episode, astrophysics student and Conversation intern Cameron Furlong goes to SSO to check out the huge Anglo Australian Telescope (AAT), the largest optical telescope in Australia.
And we hear about Huntsman, a new specialised telescope that uses off-the-shelf Canon camera lenses – a bit like those you see sports photographers using at the cricket or the footy – to study very faint regions of space around other galaxies.
Listen in to hear more about some of the most fascinating space research underway in Australia – and how, despite gruelling hours and endless paperwork, astronomers retain their sense of wonder for the night sky.
“For me, it means remembering how small I am in this enormous Universe. I think it’s very easy to forget, when you go about your daily life,” said Richard McDermid, an ARC Future Fellow and astronomer at Macquarie University.
“It’s nice to get back into it to a dark place and having a clear sky. And then you get to remember all the interesting and fascinating things, the size, the grandeur and the peacefulness of being in the dark.”
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There is a widespread belief dingoes are as good as extinct in New South Wales and nearly all dog-like animals in the wild are simply wild dogs. This belief is bolstered by legislation and policies in NSW, which have removed the word dingo and refer only to “wild dogs”.
But our research, recently published in the journal Conservation Genetics, challenges this assumption. We performed DNA ancestry testing, much like the ancestry tests available to people, on 783 wild canines killed as part of pest control measures in NSW.
Roughly one in four of the animals we tested were pure dingoes, and most were genetically more than three-quarters dingo. Only 5 of the 783 animals we tested turned out to be feral domestic dogs with no dingo ancestry.
This is not entirely surprising. Domestic pet and working dogs have lived alongside dingoes for centuries. Widespread killing of dingoes also increases the risk of hybridisation because it breaks family groups apart, giving domestic dogs the opportunity to mate with dingoes. Small populations also have a higher risk of hybridisation.
Hybridisation is generally considered detrimental to conservation because it alters the genome. In the case of dingoes, hybridisation is a problem because hybrids may be different to dingoes and “true” dingoes will eventually disappear.
While our results show dingoes still exist and their genes are predominate, their conservation will be greatly helped if we can prevent further interbreeding with domestic dogs.
Time to resurrect the dingo
Our study has important implications for both how we describe dingoes, and the future conservation of dingoes in NSW. Most of the animals labelled as wild dogs in NSW had predominantly dingo DNA, and fewer than 1% were actually feral dogs.
The term wild dog obfuscates the identity of wild animals whose genes are mostly dingo but sometimes carry dog genes. For all intents and purposes, these animals have dingo DNA, look like dingoes and behave like dingoes, and consequently should be labelled as dingoes rather than escaped pets gone wild.
Hotspots with high dingo ancestry have significant conservation value and urgently need new management plans to ensure these pure dingo populations are protected from hybridisation. These populations could be protected by restricting the killing of dingoes in these areas and restricting access to domestic dogs on public land such as state forests.
Further ancestry testing should be conducted in more areas to determine whether there are other pockets of high dingo purity in NSW.
Undeniably, dingoes can negatively impact livestock producers, especially sheep farmers. Non-lethal strategies such as electric or exclusion fencing, and livestock guarding animals such as dogs, llamas and donkeys, may balance the need to conserve dingoes and protect vulnerable livestock.
Sydney’s Inner West Council has a new policy that it is reported means “residents will no longer need to seek council approval to prune or remove trees within three metres of an existing home or structure”. Hold on, don’t reach for that chainsaw yet, because research shows good green infrastructure – trees, green roofs and walls – can add value to your home.
Green infrastructure offers significant, economic, social and environmental benefits. Urban greening is particularly important in dense urban areas like Sydney’s Inner West. Among its benefits, green infrastructure:
A 2017 study focusing on three Sydney suburbs found a 10% increase in street tree canopy could increase property values by A$50,000 on average. And the shading effect of trees can reduce energy bills by up to A$800 a year in Sydney. So retaining your green infrastructure – your trees, that is – can deliver direct financial gains.
On a larger scale, a collaborative project with Horticulture Innovation Australia Limited compared carbon and economic benefits from urban trees considering different landuses along sections of two roads in Sydney. Higher benefits were recorded for the Pacific Highway, with 106 trees per hectare and 58.6% residential land use, compared to Parramatta Road, with 70 trees per hectare and 15.8% residential.
For the Pacific Highway section, total carbon storage and the structural value of trees (the cost of replacing a tree with a similar tree) were estimated at A$1.64 million and A$640 million respectively. Trees were also valuable for carbon sequestration and removing air pollution.
Tree species, age, health and density, as well as land use, are key indicators for financial and wider ecosystem benefits. Specifically, urban trees in private yards in residential areas are vital in providing individual landowner and collective government/non-government benefits.
Challenges of growth
As populations grow, cities increase density, with less green infrastructure. The loss of greenery affects the natural environment and both human and non-human well-being.
Trees and other green infrastructure reduce some impacts of urban density. However, policies, government incentives and national priorities can produce progress in urban greening or lead to setbacks. In the case of the Inner West Council, for instance, the inability to fund monitoring of changes in tree cover could lead to reductions at the very time when we need more canopy cover.
Key concerns include installation and maintenance costs of green infrastructure (trees, green roofs and walls) in property development, and tree root damage. Knowledge and skills are needed to maintain green infrastructure. As a result, developers often consider other options more feasible.
In the short and long term, multiple performance benefits and economic and environmental values are needed to establish the viability of green infrastructure.
Stockholm shares many issues found in Australian cities. Stockholm houses over 20% of Sweden’s inhabitants, is increasing in density and redeveloping land to house a growing population. Aiming to be fossil-free by 2050, Stockholm acknowledges the built environment’s role in limiting climate change and its impacts.
In a research project we intend to use virtual reality (VR) and electroencephalogram (EEG) technology to assess perceptions of green infrastructure and reactions to it in various spaces.
Our project combines VR with EEG hardware, which measures human reactions to stimuli, to learn how people perceive and value green infrastructure in residential development.
Identifying all the value of green infrastructure
The many benefits of green infrastructure are both tangible and non-tangible. Economic benefits include:
those that directly benefit owners, occupants or investors – stormwater, increased property values and energy savings
other financial impacts – greenhouse gas savings, market-based savings and community benefits.
The various approaches to evaluating net value present a challenge in quantifying the value of green infrastructure. The most common – cost-benefit analysis, triple bottom line, life cycle assessment and life cycle costing – are all inadequate for evaluating trade-offs between economic and environmental performance. Conventional cost-benefit analysis is insufficient for investment analysis, as it doesn’t include environmental costs and benefits.
This is salient for green infrastructure, as owners/investors incur substantial direct costs, whereas various shareholders share the value. Perhaps, in recognition of the shared value, a range of subsidies could be adopted to compensate investors. Discounted rates anyone?
Recent efforts to evaluate the business case for green infrastructure include attempts to identify and quantify the creation of economic, environment and community/social value. However, an approach that includes a more comprehensive set of value drivers is needed to do this. This is the gap we aim to fill.
The results of experiments using VR and EEG technology and semi-structured interviews will provide a comprehensive understanding of green infrastructure. This will be correlated with capital and rental values to determine various degrees of willingness to pay.
With this knowledge, property developers in Sweden and Australia will be able to make a more informed and holistic business case for increasing green infrastructure for more liveable, healthy cities.
Maybe we can then persuade more people, including those in the Inner West, to hang onto their trees and leave the chainsaws in the garage.
The plan to manage water in the Barwon-Darling is not working, according to a draft review released last week.
The New South Wales Natural Resources Commission, which released the draft report, found the Barwon-Darling is an “ecosystem in crisis”. The report provides a robust blueprint for a more sustainable water-sharing plan.
The review confirms criticism the existing plan gives too much water to irrigators and has added to pressures on the entire Murray-Darling ecosystem.
The draft review examines the 2012 Water Sharing Plan for the Barwon-Darling, which covers 1,600km of the river from Mungindi to Wilcannia. The river here flows south-west through a relatively narrow floodplain with a tightly meandering channel and a highly variable flow pattern.
The river is unregulated and depends heavily on upstream rivers for its water (for example, Condamine–Balonne, Border rivers, Gwydir and Namoi).
January’s massive fish kills around Menindee are only the most recent example of the pressures on the river’s ecosystems. Alongside the fish deaths, research has shown that other aquatic species in the system, such as river mussels, have suffered losses that will take many decades to recover.
Communities that live along the river told the commission people can no longer fish, swim or drink the river water. Graziers struggle to provide water for their stock because the river dries up more often.
Indigenous communities are particularly affected because without water their strong connection to the river – the Barka – is being damaged. A Barkandji elder told the commission:
The river is everything. It’s my life, my culture. You take the water away from us, we’ve got nothing.
While the review found drought, upstream water extraction in NSW and Queensland and climate change have all contributed to these problems, the greatest effect comes from inappropriate water-sharing rules, particularly when water levels are low.
The law underpinning river management in NSW prioritises protecting the environment and basic landholder rights (including native title) over irrigation. However, the commission found the current plan does not achieve this.
In fact, the plan has been highly controversial since it was enacted in 2012. This in large parts arose because major changes were made between the draft plan circulated in 2011 and the actual plan gazetted in 2012. The commission documents 16 such changes in the review and rates six as substantial.
The NSW government did not publicly explain the reason for such significant alteration in 2012, but there has been much speculation powerful vested interests influenced the government to provide more water for irrigation.
The most important effect of these changes was letting irrigators take water even when the river is very low. The review concludes:
These provisions benefit the economic interests of a few upstream users over the ecological and social needs of the many.
The review recommends the NSW government urgently change water-sharing rules so these better comply with the legal requirements to protect the environment and other water users, restore community trust and make the river more resilient to future shocks.
Key priorities for the NSW government are:
redesigning the water-sharing rules so environmental protection and basic landholder rights cannot be harmed by lesser priorities such as irrigation
introduce new flow targets to more effectively protect critical ecosystems and enhance river health
change rules relating to water extractions by A Class licence holders during critical low-flow periods, particularly those relating to commence-to-pump, cease-to-pump, and the size of pumps.
introduce and enforce more effective metering and monitoring
develop strategies and rules that address the inevitable impacts of climate change
develop and implement more integrated management of water resources in the northern Murray-Darling Basin.
The commission did note there have been positive changes to the NSW government’s approach to water policy and management since the ABC 4 Corners report Pumped in 2017 and the subsequent Ken Matthews report.
However, the Murray-Darling Basin Plan required NSW to complete a new water resource plan for the Barwon-Darling River by June 2019. The state missed this deadline. The NSW water minister has requested an extension to December 31 2019. A recent assessment by the Murray-Darling Basin Authority suggests NSW is still some way from completing this water resource plan.
While NSW delays, the Barwon-Darling river system and its communities suffer. The NSW government now has an excellent blueprint for a new plan. It must urgently implement the review’s 29 recommendations and complete a new plan for the Barwon-Darling before the end of 2019.
The New South Wales government last week revealed plans to ease shooting restrictions on feral deer. If the plans go ahead, deer will be stripped of their status as a game animal and will no longer be afforded protection under the state’s animal control laws.
This will mean that a game hunting licence would not be required for recreational, commercial and professional hunting of deer species. Restrictions on how and when deer can be hunted would also be lifted.
Feral deer will be treated the same as other pest animals in NSW, including red foxes, feral cats and rabbits.
Removing the game status of deer is the next logical step towards controlling existing deer numbers in NSW, and slowing their spread to new areas. Deer currently cover 17% of NSW, and this area has more than doubled since 2009.
Feral deer remain one of Australia’s least studied introduced mammals. Yet the evidence shows they have a substantial impact on Australia’s ecosystems and agriculture.
Since 2005, grazing and environmental damage by feral deer has been listed as a key threatening process under NSW legislation. Deer are known to graze on threatened plant species, and also cause erosion and soil compaction. They damage pasture; destroy fences and contaminate water sources; harm trees via antler rubbing; rip up the ground during rutting season; and potentially contribute to the spread of livestock diseases.
Ground-based shooting is the main way to manage deer in the urban fringes, regional areas and national parks. Unfortunately, coordinated ground shoots have only been effective for areas of less than 1,000 hectares, and there is no evidence that uncoordinated shooting by recreational hunters actually works to control deer on a widespread basis.
Aerial shooting can potentially be more successful over large tracts of land, but may not be a good option when tree cover is high and visibility is low. Poison baiting could help, although there is no method available to deliver baits safely, effectively and specifically to deer.
Irrespective of the control method, a coordinated approach is needed. We need a strategy that not only controls deer where damage is worst, but also prevents their spread to new areas. This will require NSW to work closely with the ACT and Victoria.
Rigorous monitoring will also be vital. This is important to gauge success (how many deer were culled, and the ethics of shooting, trapping and baiting), and to determine whether the control efforts have unintended impacts on the environment, such as deer carcasses providing food for scavenging pests.
Scavenging pests have been observed feeding on carcasses, but whether culling deer and other feral animals actually increases their abundance and impacts is unknown. Carcasses also provide a source of food for native scavengers such as eagles and ravens, and are integral to the structure and function of ecosystems.
The negative and positive impacts of deer culling on the broader ecosystem therefore needs consideration when developing and implementing monitoring plans. NSW can be the leader in this regard, starting from day one after removing the status of the deer as a game species.