Drones, detection dogs, poo spotting: what’s the best way to conduct Australia’s Great Koala Count

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Romane H. Cristescu, University of the Sunshine Coast; Celine Frere, University of the Sunshine Coast, and Desley Whisson, Deakin University

Federal environment minister Sussan Ley this week announced A$2 million for a national audit of Australia’s koalas, as part of an A$18 million package to protect the vulnerable species.

The funding might seem like a lot – and, truth be told, it is more than most threatened species receive. But the national distribution of koalas is vast, so the funding equates to about A$1.40 to survey a square kilometre. That means the way koalas are counted in the audit must be carefully considered.

Koalas are notoriously difficult to detect, and counts so far have been fairly unreliable. That can make it hard to get an accurate picture of how koalas are faring, and to know where intensive conservation effort is needed – especially after devastating events such as last summer’s bushfires.

Methods for counting koalas range from the traditional – people at ground level looking up into the trees – to the high-tech, such as heat-seeking drones. So let’s look at each method, and how we can best get a handle on Australia’s koala numbers.

Environment Minister Sussan Ley has pledged $2 million for a national koala count.
Glenn Hunt/AAP

Why we need to know koala numbers

Gathering data about species distribution and population size is crucial, because governments use it to assess a species’ status and decide what protection it needs.

In announcing the funding, Ley said the new audit aims to fill data gaps, identify where koala habitat can be expanded, and establish an annual monitoring program.

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So far, population estimates for koalas at the state and national level are rare and highly uncertain. For example, the last national koala count in 2012 estimated 33,000-153,000 in Queensland, 14,000–73,000 in NSW and 96,000-378,000 in the southern states.

This uncertainty can make it hard to detect changes in population trends quickly enough to do something about the threat, such as by limiting development or logging. However, the new audit can use methods not available in 2012, which should help with accuracy.

To date, estimates of koala numbers have been highly uncertain.
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So how do you actually count koalas?

Finding a koala can be difficult. There may be few individuals spread over large areas. And koalas are well camouflaged and quiet, unless bellowing. Finally, they can sit high in the tree canopy.

In numerous research and management programs, we have observed that even the most experienced koala spotter may only see 20–80% of koalas present at a site, especially if the vegetation is thick or the terrain difficult to move through.

Romane Cristescu with detection dog USC x IFAW detection dog Bear. Detection dogs have been trained to locate koala and their scats.
Detection Dogs for Conservation

Making the job even harder, existing koala habitat maps can be highly inaccurate and miss unexpected hotspots. However, computer modelling using the latest methods, if carefully validated on the ground, can produce more accurate maps.

Traditional surveys involve multiple people independently searching the same area, and correcting counts based on the number of koalas each observer sees. This helps account for the difficulties in koala counting, but it’s hard, slow and costly work.

Searching for koala scat (poo) also is a common method of determining koala habitat – wherever koalas spend time, they will leave scats. However, the small brown pellets are easily missed, and large surveys for scats are time consuming.

Detection dogs have been trained to locate koala scats: in one study, dogs were shown to be 150% more accurate and 20 times quicker than humans.

And because male koalas bellow during the breeding season, koalas can also be detected with acoustic surveys. Audio recorders are left at a survey sites and the recordings scanned for bellows to determine whether koalas are present.

Recently, heat-seeking drones have also been used to detect koalas. This method can be accurate and effective, especially in difficult terrain. We used them extensively to find surviving koalas after the 2019-20 bushfires.

Citizen scientists can also collect important data about koalas. Smartphone apps allow the community to report sightings around Australia, helping to build a picture of where koalas have been seen. However, these sightings are often limited to areas commonly traversed by people, such as in suburbia, near walking tracks and on private property.

Everyday citizens can help with koala counting.
Shutterstock

Getting the koala count right

All these methods involve a complex mix of strengths and weaknesses, which means the audit will need input from koala ecologists if it’s to be successful. Survey methods and sites must be chosen strategically to maximise the benefits of the funding.

Robust research data exists, but is patchy across the koala’s entire range. The first step could include collating all current data, including community sightings, to determine where additional surveys are needed. This will allow for funding to be prioritised to fill data gaps.

It is promising that the announcement includes monitoring over the long term. This will help identify population trends and better understand the response of koalas to ongoing threats. It will also reveal whether actions to address koala threats are working.

Finally, while threats to koalas are generally well understood, they can vary between populations. So the audit should allow for “threat mapping” – identifying threats and looking for ways to mitigate them.

Saving an iconic species

Last summer’s bushfires highlighted how koalas, and other native species, are vulnerable to climate change. And the clearing of koala habitat continues, at times illegally.

Government inquiries and reviews have shown state and federal environment laws are not preventing the decline of koalas and other wildlife. The federal laws are still under review.

However, the new funding underpins an important step – accurate mapping of koalas and their habitat for protection and restoration. This is a crucial task in protecting the future of this iconic Australian species.

The koala count is critical to protecting the species.
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Romane H. Cristescu, Posdoc in Ecology, University of the Sunshine Coast; Celine Frere, Senior lecturer, University of the Sunshine Coast, and Desley Whisson, Senior Lecturer in Wildlife and Conservation Biology, School of Life and Environmental Sciences, Deakin University

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

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Getting closer to a much better count of Africa’s lions

A young lion cub rests in the branches of a large euphorbia tree in Uganda’s Queen Elizabeth Conservation Area.
Alex Braczkowski, Author provided

Alexander Richard Braczkowski, Griffith University; Duan Biggs, Griffith University; James R. Allan, University of Amsterdam, and Martine Maron, The University of Queensland

African lions are one of the world’s favourite animals. But their numbers have been shrinking over the past century, especially over the past 30 years. Some scientists estimate that their numbers have halved since 1994.

Estimates of the total population of Africa’s king of beasts vary, but a recent CITES report suggested that only about 25,000 remain in the wild, across 102 populations in Africa. But the numbers in this report aren’t particularly reliable. Most used traditional survey approaches – like counts of lion footprints, audio lure surveys or expert opinion – and many were not peer-reviewed.

These traditional methods of counting lions produce highly uncertain estimates. A count of lions using their footprints may give you an estimate of, say, 50 lions in an area. But the uncertainty around this estimate could be between 15 and 100 individuals. This large uncertainty makes tracking how lion populations change from year to year nearly impossible. Our recent review shows that the majority of methods used to count African and Asiatic lions use these less robust methods.

Two young lions rest in the branches of a Euphorbia tree on the Kasenyi Plains of Queen Elizabeth National Park.
Alex Braczkowski

Making sure that lion numbers are accurate and reasonably precise is key for the species’ conservation. Estimates of lion numbers underpin their classification as ‘vulnerable’. They also form the backbone for controversial management practices like the setting of trophy hunting quotas.

The good news is that better ways of counting lions are being developed. So called spatially explicit capture-recapture methods are useful for conservation because they tell us not only how many animals live in an area, but how they move in a landscape, what their sex ratios are and even where their highest numbers are located. This method has been used to count tigers, leopards, jaguars and mountain lions for over a decade but it is only now becoming popular for lions.

A review of 169 peer-reviewed scientific articles (Web of Science and Google Scholar) showed many lion abundance and density estimates rely on traditional methods like audio lure or track surveys.

Spatially explicit capture-recapture methods use a mathematical model which incorporates the individual identity of animals (usually from photographs of natural body markings, spot patterns or even whisker spots) and their location in a landscape. By identifying and “marking” individuals over a period of time an estimate can be made of the total number of animals that live in an area.

Better methods from East Africa

This method was first used to count lions in a 2014 study in Kenya’s Maasai Mara. The lead authors capitalised on a historic way of identifying lions: their whiskers. Every lion in the wild has a unique whisker spot pattern, very much like a human fingerprint.

Recently, some of us applied this technique in a count of African lions in southwestern Uganda, in a region known as the Queen Elizabeth Conservation Area. These lions are interesting because they have a rare culture of tree-climbing. This means they have great local tourism value as each lion raises about USD$ 14 000 annually in park fees.

The status of lions in Uganda was not previously very well understood. After a wave of intense poaching during the unstable Idi Amin and Milton Obote regimes – 1971 to 1985 – during which time wildlife numbers plummeted.

But recent aerial surveys and radio-collaring studies suggested that lion prey numbers were recovering. A radio collaring study of lions from 2006 to 2010 also showed that lion home range sizes were small, and because range size is predicted by abundant prey, this suggested lions here were in good health.

Uganda’s lions in peril

From October 2017 to February 2018 we drove more than 8 000 km in 93 days searching for lions in the Queen Elizabeth Conservation Area. We obtained 165 lion detections. Using individual identifications from photos, we calculated that on average one could expect to find about 3 individual lions per 100 square kilometres, with a total of 71 lions in the entire area.

Scientists during a census of the lions in Uganda’s Queen Elizabeth Conservation Area.
Steve Winter

We used the spatially explicit capture-recapture method to assess how lion movements had changed from the home range study performed a decade earlier. Worryingly, our results showed that lions had increased their ranges significantly in just 10 years – above 400% for male lions and above 100% for females.

Also, there was only one female for every male in the wild. This is very different to other African lion populations which have a much higher proportion of females relative to males (about two females for every male).

Next steps

From the standpoint of lion conservation and recovery these results are concerning. But, on a positive note, this finding has provided a timely alert. And we recommend the use of this relatively novel survey methodology to assess other lion populations across Africa.

Four young lion cubs trigger a camera trap set on a waterbuck kill on Queen Elizabeth’s Kasenyi Plains.
Alex Braczkowski

More recently, in 2020, another rigorous study at Lake Nakuru National Park, Kenya, applied this approach and found that this method estimated lion population size to be about a sixth of what was previously thought. The Kenya Wildlife Service, in collaboration with local partners is now using spatially explicit capture-recapture in an ambitious nationwide survey of lions and other large carnivores at all potential strongholds across Kenya.

More broadly, these results further bolster the view that by relying on ad hoc, indirect methods to detect lion population trends, we may end up with misleading answers and fail to direct scarce conservation resources optimally.

We argue that all stakeholders involved in lion conservation across Africa and Asia should use rigorous survey methods to keep track of lion populations. These results should then form appropriate baselines for continent-wide reports on lion abundance, and help inform strategies aimed at their recovery.

Alexander Richard Braczkowski, Research Associate, Griffith University; Duan Biggs, Senior Research Fellow Social-Ecological Systems & Resilience, Griffith University; James R. Allan, Postdoctoral research fellow, University of Amsterdam, and Martine Maron, ARC Future Fellow and Professor of Environmental Management, The University of Queensland

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

Climate explained: why we need to focus on increased consumption as much as population growth

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Glenn Banks, Massey University

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Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz

Almost every threat to modern humanity can be traced simply to our out-of-control population growth (think about arable land going to housing; continued growth in demand for petroleum fuels). Is anything being done to contain population growth on a national and international scale?

The question of population is more complex that it may seem – in the context of climate change as well as other issues such as biodiversity loss and international development.

As a starting point, let’s look at the statement “out-of-control population growth”. In fact, population growth is more “in control” than it has been for the past 50 years.

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Population isn’t growing everywhere

The global rate of population growth has been declining from just over 2% per year in 1970 to less than 1.1% in 2020 (and this estimate was made before COVID-19 erupted globally).

To put this in perspective, if the 2% growth rate had continued, the world’s population would have doubled in 35 years. At a 1.1% growth rate, it would now be set to double in 63 years – but the growth rate is still declining, so the doubling time will be lengthened again.

Population growth also varies significantly between countries. Among the 20 most populous countries in the world, three countries have growth rates of more than 2.5% – Ethiopia, Nigeria and the Democratic Republic of Congo – while Japan’s population is in decline (with a negative growth rate, -0.3%) and China, Russia, Germany and Thailand all have very low growth rates.

These growth rates vary in part because the population structures are very different across countries. Japan has an aged population, with 28% over 65 years and just 12% under 15 years. Nigeria has only 3% of people in the over-65 bracket and 44% under 15.

For comparison, 20% of New Zealanders are younger than 15 and 16% are older than 65. For Australia, the respective figures are 18% and 17%.

Migration also makes a significant contribution in some countries, propping up the working-age population and shaping the demographic structure. History and levels of economic development play an important role too: higher-income countries almost consistently have smaller families and lower growth rates.

Rise in consumption

It’s certainly valid to link population growth (even a more limited “in control” population growth) with climate change and loss of land. Everything else being equal, more people means more space taken up, more resources consumed and more carbon emitted.

But while population growth has slowed since the 1970s, resource consumption hasn’t. For example, there is no equivalent decline in fossil fuel use since the 1970s.

Fuel consumption varies throughout the world.
Flickr/Minnesota Pollution Control Agency, CC BY-NC

This is an area where not everyone is equal. If all people were to use the same amount of resources (fossil fuels, timber, minerals, arable land etc), then of course total resource use and carbon would rise. But resource use varies dramatically globally.

If we look at oil consumption per person in 2019, the average American used almost twice as much as someone in Japan, the second oil-thirstiest populous nation, and almost 350 times as much as a person living in the Democratic Republic of Congo.

It is an easy out for us in the industrialised world to say “out-of-control population growth” is killing the planet, when instead it is equally valid – but more confronting – to say our out-of-control consumption is killing the planet.

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Population growth slows when women are educated

To come to the final part of the question: is anything being done to contain population growth, on a national or international scale?

Even if we set aside the argument above that population is not the only issue, or even the most significant one, in terms of threats to humanity, what factors might influence population growth in parts of the world where it is high?

Things are being done, but they may not be what most people expect. It has long been shown that as incomes rise and health care improves, more children survive and people tend to have smaller families.

This effect is not instantaneous. There is a lag where population growth rates might rise first before they begin to drop. This demographic transition is a relatively consistent pattern globally.

But, at the country level, the single most significant influence on reducing fertility rates, family size and overall population growth is access to education for girls and women.

Fertility rates drop when girls get access to education.
Oksana Kuzmina/Shutterstock

One study in 2016, drawing on World Bank population data across a wide range of countries, found:

… the main driver of overall fertility reduction is clearly the change in proportions of women at each education level.

In relation to climate change action, this study specifically notes:

It is education, or more specifically girls’ education, that is far more likely to result in lower carbon emissions than a shift to renewables, improved agricultural practices, urban public transport, or any other strategy now being contemplated.

Recent research looked at how the global population might change if we implemented the aspirations of the 17 UN Sustainable Development Goals. It found the change would be significant and could even mean the global population stabilises by mid-century.

Glenn Banks, Professor of Geography and Head of School, School of People, Environment and Planning, Massey University

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

As Earth’s population heads to 10 billion, does anything Australians do on climate change matter?

The United Nations predicts the world will be home to nearly 10 billion people by 2050 – making global greenhouse emission cuts ever more urgent.
NASA/Joshua Stevens

Mark Beeson, University of Western Australia

As unprecedented bushfires continue to ravage the country, Prime Minister Scott Morrison and his government have been rightly criticised for their reluctance to talk about the underlying drivers of this crisis. Yet it’s not hard to see why they might be dumbstruck.

The human race has never had to grapple with a problem as large, complex or urgent as climate change. It’s not that there aren’t solutions available. There are already some hopeful signs of an energy transition in Australia. As Professor Ross Garnaut has explained, it would be in Australia’s economic interests to become a low-carbon energy superpower.

To successfully tackle climate change will require some painful transitions domestically, and unprecedented levels of international coordination and cooperation. But that isn’t happening. Global action to cut emissions is falling far short of what’s needed – and meanwhile, though it’s controversial to mention, the world’s population quietly climbs ever higher.

Our growing population challenge

The United Nations’ World Population Prospects 2019 report forecast that by 2027, India will overtake China as the world’s most populous country.

By 2050, the UN predicts that the world’s population will be nearly 10 billion, up from 7.7 billion now. Nine countries are expected to be home to more than half of that growth: India, Nigeria, Pakistan, the Congo, Ethiopia, Tanzania, Indonesia, Egypt and the United States. The population of sub-Saharan Africa is expected to double by 2050 (a 99% increase), while Australia and New Zealand are expected to grow more slowly (28% increase).

The world’s population growth rate in recent years.
World Population Prospects 2019, United Nations, CC BY

Given how difficult climate politics have been here in Australia, why would we expect it to be any more politically feasible in say, India, which claims the right to develop as we did? However self-serving Australian coal supporters’ arguments about lifting Indians out of poverty are, the underlying questions of national autonomy and the ‘right’ to develop are not easily refuted.

Even talking about demography is asking for trouble – especially if it becomes caught up with questions of race, identity and the most fundamental of human rights, the right to reproduce.

While reducing population growth is plainly important in the long-term, it isn’t a quick fix for all our environmental problems. In the meantime, research has shown that supporting education for girls in poor countries is one of the single most important things we can do now to address this issue.

How Australia can show leadership

I think we need to understand that global emissions don’t have an accent, they come from many countries and we need to look at a global solution… – Prime Minister Scott Morrison on Insiders, ABC, 12 January 2020

This is the central defence of business as usual: there’s no point in Australia making huge sacrifices and ‘wrecking’ (or transforming, depending on your perspective) the economy if no one else is doing so. We contribute less than 2% to global greenhouse emissions, so – some claim – we can’t make any real difference.

As outlined in my 2019 book, Environmental Populism: The Politics of Survival in the Anthropocene, nations such as Australia can play a useful role by showing what an enlightened country, with the capacity and incentive to act, might do. If we don’t have the means and the compelling environmental reasons to make tough but meaningful policy choices, who does?

But even in the unlikely event that Australians collectively retrofitted the entire economy along sustainable lines, there would still be a lot of the world that wouldn’t, or couldn’t even if they wanted to. The development imperative really is non-negotiable in India, China and the more impoverished states of sub-Saharan Africa.

Will China lead the way?

From the privileged perspective of wealthy Australians, the ‘good’ news is that the ecological footprint of the average Ethiopian is seven times smaller than ours. India’s average is even less, despite all the recent development. However, people in India and Ethiopia may not think that’s a good thing.

One of the paradoxical impacts of globalisation is that everyone is increasingly conscious of their relative place in the international scheme of things. The legitimacy of governments – especially unelected authoritarian regimes like China’s – increasingly revolves around their capacity to deliver jobs and rising living standards. Where governments can’t deliver, the population vote with their feet.

As naturalist Sir David Attenborough warned last week, Australia’s current fires are another sign that “the moment of crisis has come”. He called on China for the global leadership we’ve been missing:

If the Chinese come and say: ‘Not because we are worried about the world but for our own reasons, we are going to take major steps to curb our carbon output […]’, everybody else would fall into line, one thinks. That would be the big change that one could hope would happen.

China has arguably already made the biggest contribution to our collective welfare with its highly contentious, now abandoned one-child policy. China’s population would have been around 400 million people larger without it, pushing us closer to the crisis Sir David fears.

To be clear, I’m not advocating compulsory population control, here or anywhere. But we do need to consider a future with billions more people, many of them aspiring to live as Australians do now.

Looking ahead, will Australians try to keep living as we do today? Or will we decide to set a new example of living well, without such a heavy ecological footprint? Resolving all these conundrums won’t be easy; perhaps not even possible. That’s another discomfiting reality that we may have to get used to.

Mark Beeson, Professor of International Politics, University of Western Australia

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

How to feed a growing population healthy food without ruining the planet

For many of us, a better diet means eating more fruit and vegetables.
iStock, CC BY-NC

Alessandro R Demaio, University of Copenhagen; Jessica Fanzo, Johns Hopkins University, and Mario Herrero, CSIRO

If we’re serious about feeding the world’s growing population healthy food, and not ruining the planet, we need to get used to a new style of eating. This includes cutting our Western meat and sugar intakes by around 50%, and doubling the amount of nuts, fruits, vegetables and legumes we consume.

These are the findings our the EAT-Lancet Commission, released today. The Commission brought together 37 leading experts in nutrition, agriculture, ecology, political sciences and environmental sustainability, from 16 countries.

Over two years, we mapped the links between food, health and the environment and formulated global targets for healthy diets and sustainable food production. This includes five specific strategies to achieve them through global cooperation.

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Right now, we produce, ship, eat and waste food in a way that is a lose-lose for both people and planet – but we can flip this trend.

What’s going wrong with our food supply?

Almost one billion people lack sufficient food, yet more than two billion suffer from obesity and food-related diseases such as diabetes and heart disease.

The foods causing these health epidemics – combined with the way we produce our food – are pushing our planet to the brink.

One-third of the greenhouse gas emissions that drive climate change come from food production. Our global food system leads to extensive deforestation and species extinction, while depleting our oceans, and fresh water resources.

To make matters worse, we lose or throw away around one-third of all food produced. That’s enough to feed the world’s hungry four times over, every year.

At the same time, our food systems are at risk due to environmental degradation and climate change. These food systems are essential to providing the diverse, high-quality foods we all consume every day.

A radical new approach

To improve the health of people and the planet, we’ve developed a “planetary health diet” which is globally applicable – irrespective of your geographic, economic or cultural background – and locally adaptable.

The diet is a “flexitarian” approach to eating. It’s largely composed of vegetables and fruits, wholegrains, legumes, nuts and unsaturated oils. It includes high-quality meat, dairy and sugar, but in quantities far lower than are consumed in many wealthier societies.

Many of us need to eat more veggies and less red meat.
Joshua Resnick/Shutterstock

The planetary health diet consists of:

• vegetables and fruit (550g per day per day)
• wholegrains (230 grams per day)
• dairy products such as milk and cheese (250g per day)
• protein sourced from plants, such as lentils, peas, nuts and soy foods (100 grams per day)
• small quantities of fish (28 grams per day), chicken (25 grams per day) and red meat (14 grams per day)
• eggs (1.5 per week)
• small quantities of fats (50g per day) and sugar (30g per day).

Of course, some populations don’t get nearly enough animal-source foods necessary for growth, cognitive development and optimal nutrition. Food systems in these regions need to improve access to healthy, high-quality diets for all.

The shift is radical but achievable – and is possible without any expansion in land use for agriculture. Such a shift will also see us reduce the amount of water used during production, while reducing nitrogen and phosphorous usage and runoff. This is critical to safeguarding land and ocean resources.

By 2040, our food systems should begin soaking up greenhouse emissions – rather than being a net emitter. Carbon dioxide emissions must be down to zero, while methane and nitrous oxide emissions be kept in close check.

How to get there

The commission outlines five implementable strategies for a food transformation:

1. Make healthy diets the new normal – leaving no-one behind

Shift the world to healthy, tasty and sustainable diets by investing in better public health information and implementing supportive policies. Start with kids – much can happen by changing school meals to form healthy and sustainable habits, early on.

Unhealthy food outlets and their marketing must be restricted. Informal markets and street vendors should also be encouraged to sell healthier and more sustainable food.

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2. Grow what’s best for both people and planet

Realign food system priorities for people and planet so agriculture becomes a leading contributor to sustainable development rather than the largest driver of environmental change. Examples include:

• incorporating organic farm waste into soils
• drastically reducing tillage where soil is turned and churned to prepare for growing crops
• investing more in agroforestry, where trees or shrubs are grown around or among crops or pastureland to increase biodiversity and reduce erosion
• producing a more diverse range of foods in circular farming systems that protect and enhance biodiversity, rather than farming single crops or livestock.

The measure of success in this area is that agriculture one day becomes a carbon sink, absorbing carbon dioxide from the atmosphere.

Technology can help us make better use of our farmlands.
Shutterstock

3. Produce more of the right food, from less

Move away from producing “more” food towards producing “better food”.

This means using sustainable “agroecological” practices and emerging technologies, such as applying micro doses of fertiliser via GPS-guided tractors, or improving drip irrigation and using drought-resistant food sources to get more “crop per drop” of water.

In animal production, reformulating feed to make it more nutritious would allow us to reduce the amount of grain and therefore land needed for food. Feed additives such as algae are also being developed. Tests show these can reduce methane emissions by up to 30%.

We also need to redirect subsidies and other incentives to currently under-produced crops that underpin healthy diets – notably, fruits, vegetables and nuts – rather than crops whose overconsumption drives poor health.

4. Safeguard our land and oceans

There is essentially no additional land to spare for further agricultural expansion. Degraded land must be restored or reforested. Specific strategies for curbing biodiversity loss include keeping half of the current global land area for nature, while sharing space on cultivated lands.

The same applies for our oceans. We need to protect the marine ecosystems fisheries depend on. Fish stocks must be kept at sustainable levels, while aquaculture – which currently provides more than 40% of all fish consumed – must incorporate “circular production”. This includes strategies such as sourcing protein-rich feeds from insects grown on food waste.

5. Radically reduce food losses and waste

We need to more than halve our food losses and waste.

Poor harvest scheduling, careless handling of produce and inadequate cooling and storage are some of the reasons why food is lost. Similarly, consumers must start throwing less food away. This means being more conscious about portions, better consumer understanding of “best before” and “use by” labels, and embracing the opportunities that lie in leftovers.

Circular food systems that innovate new ways to reduce or eliminate waste through reuse will also play a significant role and will additionally open new business opportunities.

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Australian communities are fighting food waste with circular economies

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For significant transformation to happen, all levels of society must be engaged, from individual consumers to policymakers and everybody along the food supply chain. These changes will not happen overnight, and they are not the responsibility of a handful of stakeholders. When it comes to food and sustainability, we are all at the decision dining table.

The EAT-Lancet Commission’s Australian launch is in Melbourne on February 1. Limited free tickets are available.

Alessandro R Demaio, Australian Medical Doctor; Fellow in Global Health & NCDs, University of Copenhagen; Jessica Fanzo, Bloomberg Distinguished Associate Professor of Global Food and Agriculture Policy and Ethics, Johns Hopkins University, and Mario Herrero, Chief Research Scientist, Food Systems and the Environment, CSIRO

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

‘Overpopulation’ and the environment: three ideas on how to discuss it in a sensitive way

Ints Vikmanis / shutterstock

Rebecca Laycock Pedersen, Keele University and David P. M. Lam, Leuphana University

Should we give up having children to save the planet? Recent news articles and scientific papers have once again raised concerns about “overpopulation” and the environmental implications of having too many humans on Earth. Many people consider bringing fewer children into the world to be the logical solution. If you read the comments section of these articles, you’ll find out what anyone who’s been in a conversation about overpopulation knows: such exchanges are polarised, emotionally loaded and conflict ridden.

Regardless of whether you think that overpopulation is the defining issue of our time, don’t think it is a real problem, or lie somewhere in between, it’s absolutely crucial we can have these conversations without further polarising the debate. In a recent comment in Environmental Research Letters, we offer three tips for having conversations about overpopulation in a more ethical, thoughtful and sensitive way.

1) Recognise the limits of individual action at home

An individual person (or a couple) acting by themselves can only do so much. It can seem like the most impactful action one can take is to have fewer children, but our capacity to act collectively can have far greater impacts than any one (or two) people can alone.

Environmental problems are so large that they are hard for us to wrap our minds around. When people are encouraged to think about these problems as individuals, it can cause them to go into denial about how much impact they can genuinely have. But research has shown that highlighting a collective responsibility for addressing environmental issues actually leads to a greater desire to act.

Often recommendations for how to be more environmentally friendly are targeted at things you do in your personal life: recycle more, eat less meat, fly less, and so on. However, businesses, universities, hospitals, churches and charities all have big environmental footprints, too. In fact, these are usually much larger than any one individual’s footprint. Therefore, individuals acting professionally within these organisations can substantially reduce their environmental impact.

For example, the head of purchasing of a large organisation may be able to make bigger reductions in their organisation’s carbon emissions through changing purchasing guidelines than they could ever make by having fewer children. So organisations, or people working on behalf of organisations with big environmental footprints, are often much more strategic actors to target when striving towards larger-scale pro-environmental changes.

2) Acknowledge some humans consume more than others

When we’re talking about population as an environmental issue, it’s important to remember that it’s not the number of people per se but rather the consumption habits that lead to environmental degradation. Seven billion Americans using as much water, plastic, petrol and meat as they do now, would be a global disaster. In many countries, however, individuals use a fraction of the average American, and Eritrea has the smallest per capita ecological footprint of all.

The average EU citizen creates 31kg of plastic waste a year.
Roman Mikhailiuk / shutterstock

So few children are being born in most developed countries that without immigration, populations would be declining. For example, in Canada, the fertility rate was 1.6 children per woman in 2011 (well below the replacement rate of 2.1). So if you think about it, the real environmental impact here has to do with how much people are consuming – and this varies widely both between and within countries.

3) Be clear: is family planning a human right?

Suggestions to have fewer children are very closely linked to the idea of birth control. Birth control has an ugly history and its knock-on effects can still be seen in China and South Korea today. In these countries, birth control led to the abortion of many female embryos as families preferred to have boys for several cultural reasons. However, today these countries face the problem of having more men than women of childbearing age which is one reason behind the trafficking of young women from other countries, such as Vietnam.

Against this backdrop, in 2012, the United Nations Population Fund declared family planning a human right. But still about 12% of women aged 15–49 globally don’t have access to family planning. This is a modern-day human rights violation happening right now.

This is why, when the suggestion of addressing environmental issues by having fewer children comes up, the conversation often switches to overpopulation and becomes fraught. Overpopulation is usually seen as a problem that puts future generations at risk. Therefore when it is raised in conversations about family planning, it’s read as a value statement: my children’s rights being violated in future are more important than the rights of those being violated now. This may not be your intended message, so be clear: should women have the right to choose when and how many children they have?

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An expanding human population is a collective challenge which incorporates values, emotions, different worldviews, and the alignment of different interests. So next time you find yourself wading into an exchange about overpopulation, be clear about your underlying assumptions. This is a conversation with many layers and we need to approach it with open minds, sensitivity, tact and compassion.

Rebecca Laycock Pedersen, PhD Researcher, Keele University and David P. M. Lam, PhD Researcher, Institute for Ethics and Transdisciplinary Stustainability Research (IETSR), Leuphana University

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

World’s Largest King Penguin Colony Has Collapsed

The link below is to an article reporting on the collapse of the world’s largest King Penguin population.

For more visit:
https://www.theguardian.com/world/2018/jul/30/worlds-largest-king-penguin-colony-has-declined-by-90

Even if you were the last rhino on Earth… why populations can’t be saved by a single breeding pair

Corey Bradshaw, Flinders University

Two days ago, the last male northern white rhino (Ceratotherium simum cottoni) died. His passing leaves two surviving members of his subspecies: both females who are unable to bear calves.

Even though it might not be quite the end of the northern white rhino because of the possibility of implanting frozen embryos in their southern cousins (C. simum simum), in practical terms, it nevertheless represents the end of a long decline for the subspecies. It also raises the question: how many individuals does a species need to persist?

Fiction writers have enthusiastically embraced this question, most often in the post-apocalypse genre. It’s a notion with a long past; the Adam and Eve myth is of course based on a single breeding pair populating the entire world, as is the case described in the Ragnarok, the final battle of the gods in Norse mythology.

This idea dovetails neatly with the image of Noah’s animals marching “two by two” into the Ark. But the science of “minimum viable populations” tells us a different story.

No inbreeding, please

The global gold standard used to assess the extinction risk of any species is the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species.

The Red List’s assessment criteria are based on the so-called “50/500 rule”. This states that to avoid inbreeding depression (the loss of “fitness” due to genetic problems), an effective population size of at least 50 individuals in a population is required.

To avoid eroding evolutionary potential (the ability of a population to evolve to cope with future environmental changes), an effective population of at least 500 is required.

The key here is that little qualifier “effective”. This refers to individuals who can breed with each other without causing inbreeding or loss of genetic diversity. A family unit, for example, might have only one or two reproductively effective members. But they would also need another, unrelated, family unit nearby for their offspring to reproduce with.

That means that the number of effective individuals is lower than the total population. On average, the ratio is about 0.1 to 0.2; that is, one effective individual (genetically speaking) for every five to ten members of the population.

This also assumes that the breeding pairs are matching up based on an optimal genetic basis – what geneticists call an “idealised population”.

In a perfect world, a breeding pair of animals would be completely unrelated and would have no chance of producing babies with any genetic defects caused by inbreeding. However, real populations rarely behave like this, so some pairs have a certain amount of relatedness. As the population gets smaller, the chance of breeding with a relative increases, which leads to more frequent and severe inbreeding.

Repopulating the world after the apocalypse

So let’s do the maths. Fifty effective individuals – the ICUN standard for avoiding inbreeding – equals a total population of 250 to 500. This means that, in a hypothetical apocalypse, humanity would need a lot more than a handful of survivors to repopulate effectively.

However, to retain evolutionary potential – to remain genetically flexible and diverse – the IUCN criteria suggest we would need at least 500 effective individuals. That requires a population of 2,500 to 5,000.

Some preliminary results emerging from ongoing research at the Centre of Excellence for Australian Biodiversity and Heritage appear to confirm this. Using both ancient DNA techniques and palaeo-demographic models, we have estimates of a minimum effective population size for Aboriginal Australians when they first appeared of about 250. This means at least several thousand had to arrive around the same time to manage to colonise the entire continent successfully.

Of course, not every species has the same ratio of effective to total population size, and not all populations necessarily need 5,000 individuals to survive. But without being able to measure the true ratio for a specific population, it helps to default to the average situation.

The idea that 50 individuals is enough to avoid inbreeding depression comes largely from laboratory populations that probably do not describe the situation for populations living in wild environments.

In species as varied as houseflies and pinkfairies, populations substantially greater than 50 individuals still succumb to inbreeding depression. So, in many cases, 50 effective individuals is in fact too low to ensure no inbreeding depression occurs. It may be that 100 effective individuals is closer to the true minimum, without even considering how populations respond to evolutionary challenges.

So, sensational analogies about the apocalypse aside, do human beings follow the same rule? We aren’t entirely sure, but evidence suggests that most species in vastly different groups roughly follow the same trend.

An emerging rule of thumb is that when a population starts to dip below several thousand individuals, it has a high likelihood of going extinct.

Corey Bradshaw, Matthew Flinders Fellow in Global Ecology, Flinders University

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

Uganda’s Bird Population

Half of an Endangered Antelope Population Has Died Within Weeks