Increasing human population density drives environmental degradation in Africa

26 06 2019

 

stumps

Almost a decade ago, I (co-) wrote a paper examining the socio-economic correlates of gross, national-scale indices of environmental performance among the world’s nations. It turned out to be rather popular, and has so far garnered over 180 citations and been cited in three major policy documents.

In addition to the more pedestrian ranking itself, we also tested which of three main socio-economic indicators best explained variation in the environmental rank — a country’s gross ‘wealth’ indicator (gross national income) turned out to explain the most, and there was no evidence to support a non-linear relationship between environmental performance and per capita wealth (the so-called environmental Kuznets curve).

Well, that was then, and this is now. Something that always bothered me about that bit of research was that in some respects, it probably unfairly disadvantaged certain countries that were in more recent phases of the ‘development’ pathway, such that environmental damage long since done in major development pulses many decades or even centuries prior to today (e.g., in much of Europe) probably meant that certain countries got a bit of an unfair advantage. In fact, the more recently developed nations probably copped a lower ranking simply because their damage was fresher

While I defend the overall conclusions of that paper, my intentions have always been since then to improve on the approach. That desire finally got the better of me, and so I (some might say unwisely) decided to focus on a particular region of the planet where some of the biggest biodiversity crunches will happen over the next few decades — Africa.

Africa is an important region to re-examine these national-scale relationships for many reasons. The first is that it’s really the only place left on the planet where there’s a semi-intact megafauna assemblage. Yes, the great Late Pleistocene megafauna extinction event did hit Africa too, but compared to all other continents, it got through that period relatively unscathed. So now we (still) have elephants, rhinos, giraffes, hippos, etc. It’s a pretty bloody special place from that perspective alone.

P1080625

Elephants in the Kruger National Park, South Africa (photo: CJA Bradshaw)

Then there’s the sheer size of the continent. Unfortunately, most mercator projections of the Earth show a rather quaint continent nuzzled comfortably in the middle of the map, when in reality, it’s a real whopper. If you don’t believe me, go to truesize.com and drag any country of interest over the African continent (it turns out that its can more or less fit all of China, Australia, USA, and India within its greater borders).

Third, most countries in Africa (barring a few rare exceptions), are still in the so-called ‘development’ phase, although some are much farther along the economic road than others. For this reason, an African nation-to-nation comparison is probably a lot fairer than comparing, say, Bolivia to Germany, or Mongolia to Canada.

Read the rest of this entry »





Inexorable rise of human population pressures in Africa

31 08 2016
© Nick Brandt

© Nick Brandt

I’ve been a bit mad preparing for an upcoming conference, so I haven’t had a lot of time lately to blog about interesting developments in the conservation world. However, it struck me today that my preparations provide ideal material for a post about the future of Africa’s biodiversity.

I’ve been lucky enough to be invited to the University of Pretoria Mammal Research Unit‘s 50th Anniversary Celebration conference to be held from 12-16 September this year in Kruger National Park. Not only will this be my first time to Africa (I know — it has taken me far too long), the conference will itself be in one of the world’s best-known protected areas.

While decidedly fortunate to be invited, I am a bit intimidated by the line-up of big brains that will be attending, and of the fact that I know next to bugger all about African mammals (in a conservation science sense, of course). Still, apparently my insight as an outsider and ‘global’ thinker might be useful, so I’ve been hard at it the last few weeks planning my talk and doing some rather interesting analyses. I want to share some of these with you now beforehand, although I won’t likely give away the big prize until after I return to Australia.

I’ve been asked to talk about human population pressures on (southern) African mammal species, which might seem simple enough until you start to delve into the complexities of just how human populations affect wildlife. It’s simply from the perspective that human changes to the environment (e.g., deforestation, agricultural expansion, hunting, climate change, etc.) do cause species to dwindle and become extinct faster than they otherwise would (hence the entire field of conservation science). However, it’s another thing entirely to attempt to predict what might happen decades or centuries down the track. Read the rest of this entry »





Keeping India’s forests

9 08 2016

I’ve just returned from a short trip to the National Centre for Biological Sciences (NCBS) in Bangalore, Karnataka, one of India’s elite biological research institutes.

Panorama of a forested landscape (Savandurga monolith in the background) just south of Bangalore, Karnataka (photo: CJA Bradshaw)

Panorama of a forested landscape (Savandurga monolith in the background) just south of Bangalore, Karnataka (photo: CJA Bradshaw)

I was invited to give a series of seminars (you can see the titles here), and hopefully establish some new collaborations. My wonderful hosts, Deepa Agashe & Jayashree Ratnam, made sure I was busy meeting nearly everyone I could in ecology and evolution, and I’m happy to say that collaborations have begun. I also think NCBS will be a wonderful conduit for future students coming to Australia.

It was my first time visiting India1, and I admit that I had many preconceptions about the country that were probably unfounded. Don’t get me wrong — many of them were spot on, such as the glorious food (I particularly liked the southern India cuisine of dhosa, iddly & the various fruit-flavoured semolina concoctions), the insanity of urban traffic, the juxtaposition of extreme wealth and extreme poverty, and the politeness of Indian society (Indians have to be some of the politest people on the planet).

But where I probably was most at fault of making incorrect assumptions was regarding the state of India’s natural ecosystems, and in particular its native forests and grasslands. Read the rest of this entry »





Buying time

27 06 2016

farmOriginally published in the Otago Daily Times by Tom McKinlay

If we don’t act soon, the world we leave our children will be in a sorry state indeed, leading Australian scientist Prof Corey Bradshaw tells Tom McKinlay.

Prof Corey Bradshaw’s 9-year-old daughter lives what sounds an idyllic existence. On their small farm outside Adelaide in South Australia, she has her chickens and her dogs and her cats, her goats and her sheep.

She’s an only child, but is not short of attention from adults and reads voraciously.

She has big plans; there are at least 25 careers she likes the look of, that she’ll undertake simultaneously: farmer, wildlife rescuer, self-sufficient bush dweller – feeding herself by shooting arrows at fish – scientist and more.

She is optimistic about the future. As she should be. A 9-year-old girl living in Australia in 2016 should regard the sky as no limit at all.

All this I learn from her father, ecologist Prof Bradshaw, who talks of his daughter with an enthusiasm unbounded.

It is fair to assume she has picked up some of her interest in the natural world from him.

He holds the Sir Hubert Wilkins Chair of Climate Change in the School of Biological Sciences at the University of Adelaide.

And the ecologist, conservation biologist and systems modeller – with a University of Otago degree – has shared a great deal of his work with his daughter.

“She’s very much a farm kid, but because of who I am she gets to hear a lot about animal and plant systems around the world, and she’s travelled a lot with me and she’s a complete fanatic of David Attenborough,” the professor says.

So far, still so idyllic. But Prof Bradshaw’s work means he is at the forefront of alerting the world to what is not right with it.

Pollution, climate change, habitat loss, extinction.

His daughter has travelled with him to see species that might not be with us by the time she grows up.

“She’s hyper-aware of extinctions, in particular, and how climate change is contributing to that,” Prof Bradshaw says.

“I don’t pull any punches with her.”

In fact, he made her cry when she was 5 explaining climate change. She hasn’t needed to travel to know the pot is on the boil. Fires have forced the family to flee its South Australian property several times, not just at the height of summer.

One of the worst fires in the region struck in May a couple of years back.

“We were on the doorstep of winter and we had one of our worst fires in 20 years.”

So even without a scientist in the family, there are certain unavoidable truths for a child growing up in 21st-century Australia.

Prof Bradshaw is coming to Dunedin next month as part of the New Zealand International Science Festival to talk on climate change, looking at it from his daughter’s perspective. Read the rest of this entry »





Killing the Koala and Poisoning the Prairie

19 10 2015

Cover-Bradshaw&Ehrlich-final

Man and the environment are meant for each other” — Tony Abbott, former Prime Minister of Australia (2014)

I know the human being and the fish can co-exist peacefully” — George W. Bush, former President of the USA (2000)

It. Has. Finally. Been. Published.

Yes, my new book with Paul Ehrlich, published by University of Chicago Press, is now available to purchase in book shops and online distributors around the world. The blog post today is a little explanatory synopsis of why we wrote the book and what it contains, but of course the real ‘meat’ is in the book. I hope you enjoy it.

In Australia, you can purchase the hard copy through Footprint Books, and the Kindle version at Amazon Australia. I also suggest that Australians might find the best deals through Booko. Electronic versions are also available through Kobo and Google Play. In the US you can order directly from University of Chicago Press, Amazon, Barnes & Noble, and many other book sellers. In the UK and Europe, the book is available from your country’s Amazon distributor. I imagine many chain and independent book sellers will be carrying the book by now, or will be soon.

My deepest thanks to all those who made it possible.

Our chance meeting in 2009 at Stanford University turned out to be auspicious, not least of which because of the publication this week of our co-authored book, Killing the Koala and Poisoning the Prairie. Australia, America and the Environment by University of Chicago Press. As a mid-career ecologist (Bradshaw) based at the University of Adelaide, it was indeed an honour to meet one of the most famous scientists (Ehrlich) in my field. With a list of books and hundreds of scientific papers under his belt, Ehrlich has been tackling major environmental issues since the 1960s. Ehrlich also has a long-time interest in Australia, having visited nearly every year during the last four decades and experienced more of the country than most Australians. Together we have observed firsthand the similarities and differences of Australia and the US, and the eyes we see through are trained as those of environmental scientists and evolutionary biologists.

So why write a book about the environmental tragedies currently unfolding in two completely different countries at opposite ends of the Earth? As it turns out, Australia and the US have much more in common environmentally than one might think, and not necessarily in a good way. Despite our vastly different floras and faunas, population densities, histories of human colonisation and soil productivities, there is an almost spooky similarity in the environmental and political problems both our countries are now experiencing. As such, we have a lot to learn about avoiding each other’s mistakes.

Ausmerica

Australia and the contiguous US are roughly equivalent in land area, both cultures are derived originally and principally from what is now the United Kingdom, and both are examples of super-consuming, super-wasting, wealthy, literate countries. Both countries also have environmental footprints that exceed most other countries on Earth, with some of the world’s highest per capita rates of greenhouse-gas emissions, water consumption, species extinctions and deforestation.  Read the rest of this entry »





When human society breaks down, wildlife suffers

22 01 2015

bearGlobal human society is a massive, consumptive beast that on average degrades its life-support system. As we’ve recently reported, this will only continue to get worse in the decades to centuries to come. Some have argued that as long as we can develop our societies enough, the impact of this massive demographic force can be lessened – a concept described by the environmental Kuznets curve. However, there is little evidence that negative societal impact on the environment is lessened as per capita wealth exceeds some threshold; unfortunately environmental damage tends to, on average, increase as a nation’s net wealth increases. That’s not to say that short-term improvements cannot be achieved through technological innovation – in fact, they will be essential to offset the inexorable growth of the global human population.

So poor nations as well as the wealthy ones are responsible for environmental damage. Poorer nations often have ineffective governance systems so they fail to enforce compliance in environmental regulations, but wealthier nations often exploit a high proportion of their natural resources, with the inevitable environmental damage this entails. In some cases however, biodiversity can temporarily escape some of the ravages of society because humans either perceive the area to be too dangerous, or otherwise have no incentive to go there. There are some good examples of the latter, such as the vicinity around the Chernobyl nuclear reactor that melted down in 1986, or the Korean demilitarised zone.

In this vein, I just stumbled across an extremely interesting paper today published online early in Conservation Biology that describes trends in charismatic wildlife (i.e., big mammals) as the former Soviet Union collapsed in 1991 and societal breakdown ensued. The authors had access to an amazing dataset that spanned the decade prior to the collapse, the decade immediately following, and a subsequent decade of societal renewal. What they found was fascinating. Read the rest of this entry »





Human population size: speeding cars can’t stop quickly

28 10 2014

Stop breeding cartoon-Steve Bell 1994Here at ConservationBytes.com, I write about pretty much anything that has anything remotely to do with biodiversity’s prospects. Whether it is something to do with ancient processes, community dynamics or the wider effects of human endeavour, anything is fair game. It’s a little strange then that despite cutting my teeth in population biology, I have never before tackled human demography. Well as of today, I have.

The press embargo has just lifted on our (Barry Brook and my) new paper in PNAS where we examine various future scenarios of the human population trajectory over the coming century. Why is this important? Simple – I’ve argued before that we could essentially stop all conservation research tomorrow and still know enough to deal with most biodiversity problems. If we could only get a handle on the socio-economic components of the threats, then we might be able to make some real progress. In other words, we need to find out how to manage humans much more than we need to know about the particulars of subtle and complex ecological processes to do the most benefit for biodiversity. Ecologists tend to navel-gaze in this arena far too much.

So I called my own bluff and turned my attention to humans. Our question was simple – how quickly could the human population be reduced to a more ‘sustainable’ size (i.e., something substantially smaller than now)? The main reason we posed that simple, yet deceptively loaded question was that both of us have at various times been faced with the question by someone in the audience that we were “ignoring the elephant in the room” of human over-population.

Read the rest of this entry »





We only have decades…

26 04 2012

… not centuries.

Here’s a little video production The Environment Institute put together that explains some of our lab‘s work and future directions.


CJA Bradshaw





One billion people still hungry

12 11 2010

 

overpopulationA few days ago, that printed mouthpiece of Murdoch’s News Corporation in Australia – The Australiani, attacked Paul Ehrlich with a spectacular piece of uninformed gibberish (‘Population bomb still a fizzer 40 years on‘) that we both feel compelled to contest.

The Australian, well-known for its ‘War on Science’, refused to give us the opportunity to respond officially in an Opinion Editorial, so we are compelled to fight back using the blogosphere and our collective networks (which, we might add, probably exceed the distribution of said newspaper). Frankly, it was no surprise that The Australian chose to ignore us.

The article in question was written by Oliver Marc Hartwich of the so-called ‘Centre for Independent Studies’, the hyper-conservative Australian propaganda machine reminiscent of the ultra-right wing American Enterprise Institute, made up of some of Australia’s most powerful business magnates and with no academic affiliation whatsoever. Anything vaguely left-of-centre and even remotely promoting environmental responsibility is considered a viable target.

Recently, we blew the whistle on an equally dangerous man and the institutes he represents – climate-denier Alan Oxley; he and the business interests he represents are responsible for more deforestation, biodiversity loss and financial inequity in South East Asia over the last few decades than almost any single group.

Now we turn our attention to expose the true colours of the Centre for Independent Studies and Mr. Hartwich. Read the rest of this entry »





Every extra human means fewer animals

8 02 2010

© The Sun

As promised some time ago when I blogged about the imminent release of the book Conservation Biology for All (edited by Navjot Sodhi and Paul Ehrlich), I am now posting a few titbits from the book.

Today’s post is a blurb from Paul Ehrlich on the human population problem for conservation of biodiversity.

The size of the human population is approaching 7 billion people, and its most fundamental connection with conservation is simple: people compete with other animals., which unlike green plants cannot make their own food. At present Homo sapiens uses, coopts, or destroys close to half of all the food available to the rest of the animal kingdom. That means that, in essence, every human being added to the population means fewer individuals can be supported in the remaining fauna.

But human population growth does much more than simply cause a proportional decline in animal biodiversity – since as you know, we degrade nature in many ways besides competing with animals for food. Each additional person will have a disproportionate negative impact on biodiversity in general. The first farmers started farming the richest soils they could find and utilised the richest and most accessible resources first (Ehrlich & Ehrlich 2005). Now much of the soil that people first farmed has been eroded away or paved over, and agriculturalists increasingly are forced to turn to marginal land to grow more food.

Equally, deeper and poorer ore deposits must be mined and smelted today, water and petroleum must come from lower quality resources, deeper wells, or (for oil) from deep beneath the ocean and must be transported over longer distances, all at ever-greater environmental cost [my addition – this is exactly why we need to embrace the cheap, safe and carbon-free energy provided by nuclear energy].

The tasks of conservation biologists are made more difficult by human population growth, as is readily seen in the I=PAT equation (Holdren & Ehrlich 1974; Ehrlich & Ehrlich 1981). Impact (I) on biodiversity is not only a result of population size (P), but of that size multiplied by affluence (A) measured as per capita consumption, and that product multiplied by another factor (T), which summarises the technologies  and socio-political-economic arrangements to service that consumption. More people surrounding a rainforest reserve in a poor nation often means more individuals invading the reserve to gather firewood or bush meat. More poeple in a rich country may mean more off-road vehicles (ORVs) assulting the biota – especially if the ORV manufacturers are politically powerful and can succesfully fight bans on their use. As poor countries’ populations grow and segments of them become more affluent, demand rises for meat and automobiles, with domesticated animals competing with or devouring native biota, cars causing all sorts of assults on biodiversity, and both adding to climate disruption. Globally, as a growing population demands greater quantities of plastics, industrial chemicals, pesticides, fertilisers, cosmetics, and medicines, the toxification of the planet escalates, bringing frightening problems for organisms ranging from polar bears to frogs (to say nothing of people!).

In sum, population growth (along with escalating consumption and the use of environmentally malign technologies) is a major driver of the ongoing destruction of populations, species, and communities that is a salient feature of the Anthropocene. Humanity , as the dominant animal (Ehrlich & Ehrlich 2008), simply out competes other animals for the planet’s productivity, and often both plants and animals for its freshwater. While dealing with more limited problems, it therefore behoves every conservation biologist to put part of her time into restraining those drivers, including working to humanely lower [sic] birth rates until population growth stops and begins a slow decline twoard a sustainable size (Daily et al. 1994).

Incidentally, Paul Ehrlich is travelling to Adelaide this year (November 2010) for some high-profile talks and meetings. Stay tuned for coverage of the events.

CJA Bradshaw

Add to FacebookAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to TwitterAdd to TechnoratiAdd to Yahoo BuzzAdd to Newsvine