Dangar Falls 360

The Peripatetic Ponderings of a Passing Person

During my break from Blogging I was able to get away for some time out. I headed off to one of my favourite spots, relatively close to here (about 3.5 to 4 hours drive, which is fairly close for Australia), Dorrigo. Dorrigo National Park is near Dorrigo – in fact it is just 2km out of town. It’s a great place and I’ll be posting some photos (and possibly video also) from the visit over the next week or so. During my visit I stayed at Dorrigo Mountain Resortjust out of Dorrigo and close by the national park. I stayed in a fairly basic cabin for two nights, which though it wouldn’t meet the standards set by most people (and I wouldn’t blame them or judge them for that) for a place to stay, I did view it as just somewhere to stay and sleep, choosing to spend…

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States’ dummy-spit over the Murray-Darling Basin Plan clouds the real facts

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The Darling River near Menindee, NSW.
Tim Keegan/Wikimedia Commons, CC BY-SA

Quentin Grafton, Crawford School of Public Policy, Australian National University and John Williams, Australian National University

Given the outraged reaction from some state water ministers to the disallowance of an amendment to the Murray Darling Basin Plan, you would be forgiven for thinking that a heinous crime had been committed against farmers in upstream states.

In fact, what happened was that the Senate voted for the Basin Plan to continue unchanged, rather than allow a modest increase in the water available to farms in the Murray Darling’s Northern Basin.

NSW water minister Niall Blair reacted by declaring that his state “will now start the process of withdrawing ourselves from the plan”, while his Victorian counterpart Lisa Neville angrily declared that “the plan is over” (despite Victoria not even being in the Northern Basin).

The political friction is generating a lot of heat, but precious little light. The debate could use a few more facts, so here they are.

Read more:
Is the Murray-Darling Basin Plan broken?

First of all, the amount of water involved in the amendment represents less than 1% of the average annual surface water extractions allowed by the Basin Plan. This is roughly equivalent to a single day’s irrigation use throughout the basin during the growing season.

In other words, irrigators already use huge amounts of water, and ensuring that environmental water recovery on the Darling River is not reduced by 70 billion litres will make very little difference to irrigators.

Second, the delivery of the environmental water target of 390 billion litres in the Northern Basin, rather than 320 billion litres as proposed in the amendment, will be undertaken with full compensation. In other words, no individual irrigator will be made worse off by allowing the original target to be delivered. No one is “taking water” from anyone.

Third, let’s just reiterate that no one has changed the Basin Plan, so the “loss” of 70 billion litres simply represents 70 billion litres less in diversions that farmers were hoping to receive in future, but now won’t.

Meanwhile, there is another amendment under consideration, to be decided by May 7, that will potentially allow farmers across the Basin to divert an extra 605 billion litres from the river. These amendments are political compromises and not part of the scientific and economic assessments that led to the Basin Plan.

Fourth, the claims by the Murray-Darling Basin Authority that the reduction in the environmental water recovery will save 200 jobs does not bear scrutiny. Jobs in agriculture have everything to do the weather, with commodity prices and the value of the Australian dollar, and very little to do with environmental water recovery. We should not spend hundreds of thousands of dollars on a consultant to get an “answer” that does not pass proper peer review in academic journals if we want good public policy outcomes.

Fifth, and finally, it’s time for some maths. The Basin Plan that was passed in 2012 had, on average, a surface water diversion limit (that is, the total amount that farmers and other water users were allowed to take) of 10,873 billion litres per year. Before surface water diversions were controlled in the mid-1990s, the average annual surface water diversions in the Basin were 10,684 billion litres per year. Between 2000-01 and 2014-15, the average was 7,956 billion litres per year.

In other words, the water limits allowed by the existing Basin Plan represent an increase, rather than a reduction, on what water users have been taking, on average, for the past 30 years. For this reason alone, we should be very careful about letting them have even more.

Read more:
The Murray Darling Basin Plan is not delivering – there’s no more time to waste

Politicians and vested interests are playing fast and loose with the facts.
Let’s be clear, the Basin Plan will not keel over because of this disallowed amendment. But it will die if the irrigators who have already received billions of dollars of taxpayers’ money, and who have billions allocated for them in the forward estimates, stop the Basin Plan from delivering on its original intentions.

It’s time our federal government stood up and defended the national interest and faithfully delivered on the original intent of the Basin Plan, and actually increase stream flows in the Basin by 2,750 billion litres per year.

The ConversationAs we and our colleagues argued earlier this month, that means establishing a truly independent scientific and expert body to evaluate the Basin’s health and what has been delivered in terms of increased net stream flows with the Basin Plan. It also means an end to further infrastructure subsidies and efficiency projects until the full facts are publicly known and scrutinised about what public benefits they provide.

Quentin Grafton, Director of the Centre for Water Economics, Environment and Policy, Crawford School of Public Policy, Australian National University and John Williams, Adjunct Professor Environment and Natural Resources, Crawford School of Public Policy, Australian National University

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


The Murray Darling Basin Plan is not delivering – there’s no more time to waste

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Despite billions spent on trying to save water in the Murray Darling Basin, results have been disappointing.
John Williams, Author provided

Quentin Grafton, Crawford School of Public Policy, Australian National University; Darla Hatton MacDonald, University of Tasmania; David Paton, University of Adelaide; Graham Harris, University of Wollongong; Henning Bjornlund, University of South Australia; Jeffery D Connor, University of South Australia; John Quiggin, The University of Queensland; John Williams, Australian National University; Lin Crase, University of South Australia; Richard Kingsford, UNSW, and Sarah Ann Wheeler, University of Adelaide

More than five years after the Murray Darling Basin Plan was implemented, it’s clear that it is not delivering on its key objectives.

The Basin Plan, at its core, is about reducing the amount of water that can be extracted from its streams, rivers and aquifers. It includes an environmental water strategy to improve the conditions of the wetlands and rivers of the basin.
The Productivity Commission will conduct a five-yearly inquiry into the effectiveness of the Basin Plan in 2018.

It is high time to explain what is really going on in the Basin and water recovery. For this reason we have all signed the Murray-Darling Basin Declaration to explain what has gone wrong, to call for a freeze on funding for new irrigation projects until the outcomes of water recovery has been fully and independently audited, and to call for the establishment of an independent, expert body to deliver on the key goals of the Water Act (2007).

Read more:
Is the Murray-Darling Basin Plan broken?

Until the ABC’s 4 Corners program in July last year, many Australians were unaware of alleged water theft and grossly deficient compliance along the Darling River. The true situation stands in stark contrast to the official view that all was well.

Some A$6 billion has been spent on “water recovery” in the Murray-Darling Basin. Of this, A$4 billion was used to subsidise irrigation infrastructure. This water recovery and the 2012 Basin Plan have been presented as a comprehensive solution to the environmental and economic problems of the Murray-Darling. But what has this huge public expenditure actually bought us?

The basin remains in a poor state. While there have been environmental improvements at specific sites, these have not been replicated basin-wide. Indeed, the federal government’s own State of the Environment Report 2016 gives a “poor” assessment on inland water flows in the basin. It reports long-term downward trends in flows since 2011 and a widespread loss of ecosystem function. Other evidence tells the same story.

Water recovery infrastructure projects have benefited irrigators, but for many of these projects there is no scientific evidence that they have actually increased net stream flows. Flows at the Murray River mouth remain inadequate. The federal government’s objective to keep the mouth open to the sea 90% of the time will almost certainly not be achieved.

The Murray mouth remains in a dire statedredging to keep it open is the norm rather than the exception, even without a drought.

How is it possible to spend A$6 billion on water recovery in the basin and have so little to show for it? It is now more than 11 years since the A$10 billion National Plan for Water Security was announced, seven years since the Millennium Drought ended, and the Australian government is already 70% towards achieving its water recovery goal. Surely, by now, Australian taxpayers – not to mention the river’s ecosystems – should be seeing a better return on this bold environmental investment?

Bad decisions

We have spent much of our working lives investigating water reforms and the health of the Murray-Darling Basin. We deplore the diversion of funds for environmental recovery into irrigation upgrades – a decision that simply represents poor public policy. Much more could have been achieved for far less, as federal government data show that buying water from willing sellers is 60% cheaper than building questionable engineering works.

To make matters worse, just two months ago the Murray-Darling Basin Authority recommended to parliament that buying back of environmental flows be reduced by 22% by July 1, 2019. This is an average annual reduction that exceeds the volume of water in Sydney Harbour.

Instead, 36 water supply projects are planned to deliver this water recovery goal. Yet 25 of them fail to satisfy the Basin Plan’s own conditions of approval such as environmental risks are adequately mitigated.

Plans are also afoot to “invest” A$1.5 billion in yet more infrastructure projects that will supposedly be the equivalent of 450 billion litres per year of water by 2024. South Australia demanded this extra water before it would approve the 2012 Basin Plan.

An algal bloom in the Darling River at Louth.
John Williams, Author provided

Despite spending A$4 billion to reduce water losses from irrigation over the past decade, we still do not know what impact this has had on the water that previously flowed from farmers’ paddocks and returned to wetlands, rivers and aquifers. The decline in these flows might have completely offset increases in environmental flows from water rights acquired through subsidies.

It is time to call it like it is. Australia is paying the price of alleged water theft, questionable environmental infrastructure water projects, and policies that subsidise private benefits at the expense of taxpayers and sustainability.

Accountability requires transparency in reporting and monitoring. So far we have failed to redirect public money away from wasteful subsidies while the rivers suffer. This is why we have signed the Murray-Darling Declaration, to highlight our concerns and to offer solutions.

Steps to change

Many aspects of water reform need to change, but three steps are necessary to deliver fully on the key objectives of the Water Act 2007. These are:

  1. Stop any further expenditures on subsidies or grants for irrigation infrastructure in the Murray-Darling Basin until there is an independent, scientific and economic audit of what A$4 billion delivered in volumes of water and environmental outcomes.

  2. Audit all water recovery and planned sustainable diversion limit (SDL) adjustments in the basin, including details of environmental water recovered, expenditures and actual environmental outcomes, especially in terms of stream flows at all special environmental assets, including the Murray Mouth.

  3. Establish an independent expert scientific advisory body to monitor the basin’s health and to publicly guide all governments to ensure the full achievement of key objectives of the Water Act 2007. These are: to restore overallocated resources to environmentally sustainable levels of extraction; and to protect, restore and provide for the ecological values and ecosystem services of the Murray-Darling Basin.

Read more:
Drought on the Murray River harms ocean life too

There is no time to waste for the Murray-Darling Basin, its rivers, environments, traditional owners, and communities. Our declaration makes it clear what must be done. The federal and state governments must be held to account and actually deliver what is needed for the basin, before the next big drought causes irreversible damage.

This article was co-authored by Richard Davis, a former chief science adviser to the National Water Commission.

The ConversationThis article is co-published with Policy Forum at the Crawford School of Public Policy.

Quentin Grafton, Director of the Centre for Water Economics, Environment and Policy, Crawford School of Public Policy, Australian National University; Darla Hatton MacDonald, Associate Professor, University of Tasmania; David Paton, Associate Professor, University of Adelaide; Graham Harris, Professorial Fellow, University of Wollongong; Henning Bjornlund, Professor, University of South Australia; Jeffery D Connor, Professor in Water Economics, University of South Australia; John Quiggin, Professor, School of Economics, The University of Queensland; John Williams, Adjunct Professor Environment and Natural Resources, Crawford School of Public Policy, Australian National University; Lin Crase, Professor of Economics and Head of School, University of South Australia; Richard Kingsford, Professor, School of Biological, Earth and Environmental Sciences, UNSW, and Sarah Ann Wheeler, Professor in Water Economics, University of Adelaide

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


Sydney’s closer to being a zero-carbon city than you think

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The potential clean energy sources are all around Sydney, just waiting to be harnessed.
Author provided

Rob Roggema, University of Technology Sydney

You live in one of the sunniest countries in the world. You might want to use that solar advantage and harvest all this free energy. Knowing that solar panels are rapidly becoming cheaper and have become feasible even in less sunny places like the UK, this should be a no-brainer.

Despite this, the Australian government has taken a step backwards at a time when we should be thinking 30 years ahead.

Further reading: Will the national energy guarantee hit pause on renewables?

Can we do it differently? Yes, we can! My ongoing research on sustainable urbanism makes it clear that if we use the available renewable resources in the Sydney region we do not need any fossil resource any more. We can become zero-carbon. (With Louisa King and Andy Van den Dobbelsteen, I have prepared a forthcoming paper, Towards Zero-Carbon Metropolitan Regions: The Example of
Sydney, in the journal SASBE.)

Enough solar power for every household

Abundant solar energy is available in the Sydney metropolitan area. If 25% of the houses each installed 35 square metres of solar panels, this could deliver all the energy for the city’s households.

We conservatively estimate a total yield of 195kWh/m2 of PV panel placed on roofs or other horizontal surfaces. The potential area of all Sydney council precincts suited for PV is estimated at around 385km2 – a quarter of the entire roof surface.

We calculate the potential total solar yield at 75.1TWh, which is more than current domestic household energy use (65.3TWh, according to the Jemena energy company).

Further reading: What’s the net cost of using renewables to hit Australia’s climate target?

Wind turbines to drive a whole city

If we install small wind turbines on land and larger turbines offshore we can harvest enough energy to fuel our electric vehicle fleet. Onshore wind turbines of 1-5MW generating capacity can be positioned to capture the prevailing southwest and northeast winds.

The turbines are placed on top of ridges, making use of the funnel effect to increase their output. We estimate around 840km of ridge lines in the Sydney metropolitan area can be used for wind turbines, enabling a total of 1,400 turbines. The total potential generation from onshore wind turbines is 6.13TWh.

Offshore turbines could in principle be placed everywhere, as the wind strength is enough to create an efficient yield. The turbines are larger than the ones on shore, capturing 5-7.5MW each, and can be placed up to 30km offshore. With these boundary conditions, an offshore wind park 45km long and 6km wide is possible. The total offshore potential then is 5.18TWh.

Altogether, then, we estimate the Sydney wind energy potential at 11.3TWh.

Around 840km of ridge lines (marked in yellow and red) in the Sydney metropolitan area can be used for wind turbines.
Author provided

Further reading: FactCheck Q&A: is coal still cheaper than renewables as an energy source?

Turning waste into biofuels

We can turn our household waste and green waste from forests, parks and public green spaces into biogas. We can then use the existing gas network to provide heating and cooling for the majority of offices.

Biomass from domestic and green waste will be processed through anaerobic fermentation in old power plants to generate biogas. Gas reserves are created, stored and delivered through the existing power plants and gas grid.

Further reading: Biogas: smells like a solution to our energy and waste problems

Algae has enormous potential for generating bio-energy. Algae can purify wastewater and at the same be harvested and processed to generate biofuels (biodiesel and biokerosene).

Specific locations to grow algae are Botany Bay and Badgerys Creek. It’s noteworthy that both are close to airports, as algae could be important in providing a sustainable fuel resource for planes.

Using algae arrays to treat the waste water of new precincts, roughly a million new households as currently planned in Western Sydney, enables the production of great quantities of biofuel. Experimental test fields show yields can be high. A minimum of 20,000 litres of biodiesel per hectare of algae ponds is possible if organic wastewater is added. This quantity is realisable in Botany Bay and in western Sydney.

Biomass fermentation of household and green waste and wastewater treatment using algae arrays can generate biogas, biodiesel and biokerosene.
Author provided

Further reading: Biofuel breakthroughs bring ‘negative emissions’ a step closer

Extracting heat from beneath the city

Shallow geothermal heat can be tapped through heat pumps and establishing closed loops in the soil. This can occur in large expanses of urban developments within the metropolitan area, which rests predominantly on deposits of Wianamatta shale in the west underlying Parramatta, Liverpool and Penrith.

Where large water surfaces are available, such as in Botany Bay or the Prospect Reservoir, heat can also be harvested from the water body.

The layers of the underlying Hawkesbury sandstone, the bedrock for much of the region, can yield deep geothermal heat. This is done by pumping water into these layers and harvesting the steam as heat, hot water or converted electricity.

Sydney’s geology offers sources of both shallow and deep theothermal heat.
Author provided

Further reading: Explainer: what is geothermal energy?

Hydropower from multiple sources

The potential sources of energy from hydro generation are diverse. Tidal energy can be harvested at the entrances of Sydney Harbour Bay and Botany Bay, where tidal differences are expected to be highest.

Port Jackson, the Sydney Harbour bay and all of its estuaries have a total area of 55km2. With a tidal difference of two metres, the total maximum energy potential of a tidal plant would be 446TWh. If Sydney could harvest 20% of this, that would be more than twice the yield of solar panels on residential roofs.

If we use the tide to generate electricity, we can also create a surge barrier connecting Middle and South Head. Given the climatic changes occurring and still ahead of us, we need to plan how to protect the city from the threats of future cyclones, storm surges and flooding.

I have written here about the potential benefits of artificially creating a Sydney Barrier Reef. The reef, 30km at most out at sea, would provide Sydney with protection from storms.

At openings along the reef, wave power generators can be placed. Like tidal power, wave power can be calculated: mass displacement times gravity. If around 10km of the Sydney shoreline had wave power vessels, the maximum energy potential would be 3.2TWh.

In the mouths of the estuaries of Sydney Harbour and Botany Bay, freshwater meets saltwater. These places have a large potential to generate “blue energy” through reverse osmosis membrane technology.

To combine protective structures with tidal generating power, an open closure barrier is proposed for the mouth of Sydney Harbour. The large central gates need to be able to accommodate the entrance of large cruise ships and to close in times of a storm surge. At the same time, a tidal plant system operates at the sides of the barrier.

An artist’s impression of the Sydney Harbour surge barrier and tidal plant.
Drawing: Andy van den Dobbelsteen, Author provided

Further reading: Catching the waves: it’s time for Australia to embrace ocean renewable energy

Master plan for a zero-carbon city

All these potential energy sources are integrated into our Master Plan for a Zero-Carbon Sydney. Each has led to design propositions that together can create a zero-carbon city.

The Zero-Carbon Sydney Master Plan maps out how the city can be fossil-free.
Author provided

The ConversationThe research shows there is enough, more than enough, potential reliable renewable energy to supply every household and industry in the region. What is needed is an awareness that Australia could be a global frontrunner in innovative energy policy, instead of a laggard.

Rob Roggema, Professor of Sustainable Urban Environments, University of Technology Sydney

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


New Royal Commission into water theft may be just the tip of iceberg for the Murray Darling Basin

Jamie Pittock, Australian National University

Last weekend South Australian Premier Jay Weatherill announced the establishment of a Royal Commission to investigate breaches of the Murray Darling Basin Agreement.

This follows apparently egregious behaviour by some irrigators and state government regulators in New South Wales. Yet the alleged theft of water in the Murray-Darling Basin is only the tip of the iceberg when we consider the institutional problems – namely the capture of state government agencies by powerful irrigation interests.

Take NSW as an example. In 1993 the then state Department of Water Resources’ North west rivers audit found the same theft, meter-tampering and questionable government oversight exposed again by the ABC’s Four Corners investigation in July.

Only half of the targeted volume of salt has been flushed out to sea and the water supply to Broken Hill and other communities has become unreliable. Moreover, floodplain forests and wetlands of international significance continue to decline, and native fish and water bird populations have flatlined.

In fact, many values are at risk in the river system that supplies water to more than 3 million people, and covers a seventh of Australia’s landmass. It is not only a few (alleged) bad apples, it is governance of water that is broken.

Problems with the existing plan

While bad behaviour in NSW is evident, of more concern is the way some state governments are frustrating implementation of the A$13 billion 2012-26 Basin Plan and associated programs to recover water for the river system.

If the Basin Plan is to improve the health of the river and its extensive floodplain forests along the lower River Murray, the water recovered for the environment needs to be released in pulses. That will be the best way to ensure it can rise out of the river channel and inundate wetlands.

Read more: Is the Murray-Darling Basin Plan broken?

In this context it is unhelpful for the Victorian Government to propose flows of around half the previously agreed size because of the objections of a small number of landowners along the Goulburn River in its Goulburn key focus area project.

Upstream, state governments have rules that allow water purchased by taxpayers for the river to be extracted by irrigators when it crosses state borders. However, they are failing to remove bottlenecks that prevent managed floods from travelling safely down rivers. They have even proposed to reduce the water available for the environment below minimum requirements.

Astonishingly, 30% of water extraction points in the Basin are still not metered and the information that is collected is not publicly available or audited so that theft can be penalised.

Sustainable management required

Sustainable management of the Murray-Darling Basin requires trust and cooperation among the responsible state, ACT and federal governments.

The alleged water theft in NSW breaks that trust, especially for SA as the downstream state that relies on the River Murray. But so too does the stalling of implementation of the Basin Plan agreement and manipulation of the rules that govern who gets what water and when they get it.

Read more: ‘Tax returns for water’: satellite-audited statements can save the Murray-Darling

The foundation of trust is transparency. As a start, there are many opportunities for online recording of water allocations and use to increase trust. It is still possible to fix implementation of the Plan.

In a report released yesterday the Wentworth Group of Concerned Scientists has identified several solutions, including metering all water diversions, completing water recovery, and investing in regional development.

The good news is that there are signs of political leadership. The Council of Australian Governments promised in June to deliver the Basin Plan “in full and on time” for its planned commencement in 2019.

Recently, Prime Minister Malcolm Turnbull recommitted the federal government to Basin Plan implementation. He endorsed the far-reaching recommendations of the Murray-Darling Basin Authority’s Basin-wide Compliance Review to strengthen enforcement of water laws and the Basin Plan, and to recover the remaining environmental water.

The SA Royal Commission

Beginning in 2018, Weatherill’s newly announced Royal Commission will investigate breaches of the Murray Darling Basin Agreement, and the Commissioner “will examine the adequacy of existing legislation and practices and make recommendations for any necessary changes.”

Most significantly, Weatherill has proposed going beyond water theft to “look into whether any legislative or policy changes since the agreement was signed in 2012 have been inconsistent with the purpose of the Basin Agreement and Basin Plan”.

Read more: We need more than just extra water to save the Murray-Darling Basin

The Royal Commission’s terms of reference are not yet available and the extent of cooperation of upstream governments is highly uncertain (NSW has already said it will not cooperate). Yet the Royal Commission could help identify ways to better meter and account for water, improve compliance and set rules to protect environmental water.

At the next Basin Ministerial Council meeting later this year the governments need to map out measures to put the Plan back on track. If it can do so, it will be endorsed at the Council of Australian Governments in 2018. This is their opportunity to articulate precisely how they will fulfil their commitment to delivering the basin plan in full and on time.

The ConversationThe Murray-Darling Basin Plan is not perfect. Implementation has problems, but with the remaining $5.1 billion allocated funds and proper leadership it can be well implemented to benefit both people and the environment.

Jamie Pittock, Director, International Programs, UNESCO Chair in Water Economics and Transboundary Water Governance, Australian National University

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


Did they mean to do that? Accident and intent in an octopuses’ garden

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A gloomy octopus perched above a bed of discarded scallop shells.
Peter Godfrey-Smith , Author provided

Martin Hing, University of Wollongong and Peter Godfrey-Smith, University of Sydney

We recently published a scientific report of octopuses living together in unusual numbers at a site on the south coast of New South Wales.

Then things got a little out of hand.

Read more: Octopuses invade Welsh beach – here are the scientific theories why

Gloomy octopus

The gloomy octopus, named for large eyes that can give the animal a doleful appearance, is the most common local octopus in NSW waters. Octopus tetricus, to use its scientific name, has usually been thought of as a solitary animal, and that has been the stereotype associated with most octopus species for many years.

The recent discovery of a site in Jervis Bay, Australia where these octopuses gather in quite high numbers is challenging that perception, and revealing some striking behaviours.

The site consists of three rocky outcrops, around which octopuses have built up an extensive bed of discarded scallop shells, mixed with some human debris.

A gloomy octopus swims over scattered scallop shells.
Peter Godfrey-Smith, Author provided

We think there is a process of “positive feedback” operating at the site. As scallops are brought back to the site to eat, the discarded shells provide material for additional octopuses to dig burrows. The shells line and stabilise the shaft-like dens. When the site was discovered in 2016, a total of 15 octopuses were present, along with several unoccupied dens.

This is the second site of its kind discovered. The first, reported in 2012, seems to have been formed around a discarded object, now very encrusted, of human origin.

The second site, which is entirely “natural,” shows that the same gathering of octopuses can occur without a “seeding” of the process by a human artefact.

At both sites, octopuses engage in quite complicated interactions – they produce displays, probe each other with their arms, and often try to evict other octopuses from their dens.

Other individuals of this species probably do live more solitary lives – when observed around Sydney, for example, they are almost always alone. This suggests that the octopuses have an ability to individually adapt their behaviour according to their circumstances.

Underwater city?

In September 2017, our scientific report of the second site was published, written with our colleagues David Scheel, Stephanie Chancellor, Stefan Linquist, and Matt Lawrence.

This paper received a good deal of media attention, with initial stories fairly accurate. But they seem to have started a self-sustaining process of their own, especially as a couple of early reports used the term “city” in their title. For example: “Scientists discover an underwater city full of gloomy octopuses.”

Gloomy octopus on the move.
Peter Godfrey-Smith, Author provided

This was probably influenced by the nickname chosen for the site, “Octlantis,” though our article did not talk about “cities” or anything similar. Soon the authors were fielding interview requests from around the world, wanting more details of the hidden octopus city and the lives of its denizens.

New online articles about the site seemed to build successively on exaggerations made in earlier articles, until our octopuses were reported as making “art” and building “fences”.

Octlantis is not a city, and no artworks, fences, or buildings have been made. In an era of rapid and unconstrained circulation of information around the internet, often with important political ramifications, the buzz around Octlantis is a reminder of how quickly rumours can arise and feed off each other, generating a literature that becomes less and less accurate at each step.

Accident versus intent

The Octlantis site does raise interesting questions about what the octopuses intend to do, and which effects of their actions are entirely inadvertent. Questions of “intent” are very difficult in work on animal behaviour, but we think some distinctions can be made – provisionally at least – in these terms.

Octopuses collect scallops for use as food. This requires them to make excursions from their den and find their way home. They bring the scallops home to eat, we assume, because it is safer than eating in the open. They also dig dens in the shell bed, and sometimes arrange shells and other objects around the edge of their den.

It seems quite likely to us that the collection of scallops and the building and maintenance of dens are all intentional behaviours (in a low-key sense of that term).

Why so gloomy, octopus?
Peter Godfrey-Smith, Author provided

Dens are sometimes maintained with some care, and octopuses will expel debris either by carrying it away, or with use of their jet propulsion mechanism, the “siphon.” But this does not imply that octopuses have any inkling that when they bring scallops back to the site, they are improving the den-building possibilities for themselves or others. Those effects may be entirely inadvertent.

Work is continuing on these animals and their unusual homes. One interesting question is whether other octopus species behave like this in some circumstances.

Another is why we observe groups of gloomy octopuses at these particular sites, and not in other areas where a solid object has been placed on the sea floor in what looks like similar circumstances.

The ConversationHow many octopuses’ gardens are out there, waiting to be discovered?

Martin Hing, PhD Researcher in marine and behavioural ecology, University of Wollongong and Peter Godfrey-Smith, Professor of History and Philosophy of Science, University of Sydney

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