South Australia’s tattered environmental remains

16 04 2014
State budget percentage expenditures for health, education and environment

South Australia State budget percentage expenditures for health, education and environment

Yesterday I gave the second keynote address at the South Australia Natural Resource Management (NRM) Science Conference at the University of Adelaide (see also a brief synopsis of Day 1 here). Unfortunately, I’m missing today’s talks because of an acute case of man cold, but at least I can stay at home and work while sipping cups of hot tea.

Many people came up afterwards and congratulated me for “being brave enough to tell the truth”, which both encouraged and distressed me – I am encouraged by the positive feedback, but distressed by the lack of action on the part of our natural resource management leaders.

The simple truth is that South Australia’s biodiversity and ecosystems are in shambles, yet few seem to appreciate this.

So for the benefit of those who couldn’t attend, I’ve uploaded my slideshow for general viewing here, and I understand that a podcast might be available in the very near future. I’ve also highlighted some key points from the talk below: Read the rest of this entry »





Essential role of carnivores on the wane

10 01 2014
© Luca Galuzzi www.galuzzi.it

© Luca Galuzzi http://www.galuzzi.it

This interesting review has just come out in Science, and because I was given a heads-up about it, I decided to do a F1000 recommendation. That’s more or less what follows, with some additional thoughts.

Ripple and colleagues can perhaps be excused for stating what might appear to many ‘in the biz’ to be blatantly obvious, but their in-depth review of the status of the world’s carnivores is a comprehensive overview of this essential guild’s worldwide plight. It not only represents an excellent teaching tool, the review elegantly summarises the current status of these essential ecosystem engineers.

The world’s 245 terrestrial carnivores might seem to be ecologically redundant to the informed given their natural rarity, low densities and cryptic behaviour, but nothing could be farther from the truth. Ecologists have only within the last decade or so revealed the essential ecosystem functions of these species (see former posts on CB.com here, here and here). The review focuses on the largest and most well-studied species, but the trends likely apply across most of the order. Read the rest of this entry »





Too small to avoid catastrophic biodiversity meltdown

27 09 2013
Chiew Larn

Chiew Larn Reservoir is surrounded by Khlong Saeng Wildlife Sanctuary and Khao Sok National Park, which together make up part of the largest block of rainforest habitat in southern Thailand (> 3500 km2). Photo: Antony Lynam

One of the perennial and probably most controversial topics in conservation ecology is when is something “too small’. By ‘something’ I mean many things, including population abundance and patch size. We’ve certainly written about the former on many occasions (see here, here, here and here for our work on minimum viable population size), with the associated controversy it elicited.

Now I (sadly) report on the tragedy of the second issue – when is a habitat fragment too small to be of much good to biodiversity?

Published today in the journal Science, Luke Gibson (of No substitute for primary forest fame) and a group of us report disturbing results about the ecological meltdown that has occurred on islands created when the Chiew Larn Reservoir of southern Thailand was flooded nearly 30 years ago by a hydroelectric dam.

As is the case in many parts of the world (e.g., Three Gorges Dam, China), hydroelectric dams can cause major ecological problems merely by flooding vast areas. In the case of Charn Liew, co-author Tony Lynam of Wildlife Conservation Society passed along to me a bit of poignant and emotive history about the local struggle to prevent the disaster.

“As the waters behind the dam were rising in 1987, Seub Nakasathien, the Superintendent of the Khlong Saeng Wildlife Sanctuary, his staff and conservationist friends, mounted an operation to capture and release animals that were caught in the flood waters.

It turned out to be distressing experience for all involved as you can see from the clips here, with the rescuers having only nets and longtail boats, and many animals dying. Ultimately most of the larger mammals disappeared quickly from the islands, leaving just the smaller fauna.

Later Seub moved to Huai Kha Khaeng Wildlife Sanctuary and fought an unsuccessful battle with poachers and loggers, which ended in him taking his own life in despair in 1990. A sad story, and his friend, a famous folk singer called Aed Carabao, wrote a song about Seub, the music of which plays in the video. Read the rest of this entry »





MPs’ ignorance puts national parks in peril

30 08 2013

greedyLed by Bill Laurance, our latest opinion editorial in the Higher Education supplement. Interestingly, it has already spawned a bilious and spittle-flecked response by Queensland’s Acting National Parks Minister, Tim Mander. Given the evidence, who’s side do you take? I’m happy that at least one of the worst culprit state governments is at least now paying some attention to the issue.

LAST week the world was appalled when Ecuador decided to open up one of its iconic national parks for petroleum development, with Leonardo di Caprio being among the chorus of dissenting voices. Yet the world should be even more disappointed in Australia, a far wealthier nation whose parks could be facing even worse threats.

Why is Australia going down this reckless path? It’s all down to the state governments – especially in Victoria, Queensland and NSW.

For the conservative politicians currently holding sway in these States, it seems it’s time to generate some quick cash while cutting park budgets – and never mind the impact on Australia’s imperilled ecosystems and biodiversity.

In Victoria, for instance, land developers are now being allowed to build hotels and other ventures in national parks. In NSW, recreational shooting and possibly logging will be allowed in parks if new legislation is passed. In NSW’s marine parks, bans on shore-based recreational fishing are being lifted [see previous post here].

Other parks in NSW and Queensland are being opened up to livestock grazing. In Morrinya National Park in Queensland, a strip of forest 20 km long was recently cleared for fencing, with new stock-watering tanks being established throughout the park. Read the rest of this entry »





Don’t blame it on the dingo

21 08 2013

dingo angelOur postdoc, Tom Prowse, has just had one of the slickest set of reviews I’ve ever seen, followed by a quick acceptance of what I think is a pretty sexy paper. Earlier this year his paper in Journal of Animal Ecology showed that thylacine (the badly named ‘Tasmanian tiger‘) was most likely not the victim of some unobserved mystery disease, but instead succumbed to what many large predators have/will: human beings. His latest effort now online in Ecology shows that the thylacine and devil extinctions on the Australian mainland were similarly the result of humans and not the scapegoat dingo. But I’ll let him explain:

‘Regime shifts’ can occur in ecosystems when sometimes even a single component is added or changed. Such additions, of say a new predator, or changes such as a rise in temperature, can fundamentally alter core ecosystem functions and processes, causing the ecosystem to switch to some alternative stable state.

Some of the most striking examples of ecological regime shifts are the mass extinctions of large mammals (‘megafauna’) during human prehistory. In Australia, human arrival and subsequent hunting pressure is implicated in the rapid extinction of about 50 mammal species by around 45 thousand years ago. The ensuing alternative stable state was comprised of a reduced diversity of predators, dominated by humans and two native marsupial predators ‑ the thylacine (also known as the marsupial ‘tiger’ or ‘wolf’) and the devil (which is now restricted to Tasmania and threatened by a debilitating, infectious cancer).

Both thylacines and devils lasted on mainland Australia for over 40 thousand years following the arrival of humans. However, a second regime shift resulted in the extinction of both these predators by about 3 thousand years ago, which was coincidentally just after dingoes were introduced to Australia. Dingoes are descended from early domestic dogs and were introduced to northern Australia from Asia by ancient traders approximately 4 thousand years ago. Today, they are Australia’s only top predator remaining, other than invasive European foxes and feral cats. Since the earliest days of European settlement, dingoes have been persecuted because they prey on livestock. During the 1880s, 5614 km of ‘dingo fence’ was constructed to protect south-east Australia’s grazing rangelands from dingo incursions. The fence is maintained to this day, and dingoes are poisoned and shot both inside and outside this barrier, despite mounting evidence that these predators play a key role in maintaining native ecosystems, largely by suppressing invasive predators.

Perhaps because the public perception of dingoes as ‘sheep-killers’ is so firmly entrenched, it has been commonly assumed that dingoes killed off the thylacines and devils on mainland Australia. People who support this view also point out that thylacines and devils persisted on the island of Tasmania, which was never colonised by dingoes (although thylacines went extinct there too in the early 1900s). To date, most discussion of the mainland thylacine and devil extinctions has focused on the possibility that dingoes disrupted the system by ‘exploitation competition’ (eating the same prey), ‘interference competition’ (wasting the native predators’ precious munching time), as well as ‘direct predation’ (dingoes actually eating devils and thylacines). Read the rest of this entry »





Saving world’s most threatened cat requires climate adaptation

23 07 2013
© CSIC Andalusia Audiovisual Bank/H. Garrido

© CSIC Andalusia Audiovisual Bank/H. Garrido

The Iberian lynx is the world’s most threatened cat, with recent counts estimating only 250 individuals surviving in the wild. Recent declines of Iberian lynx have been associated with sharp regional reductions in the abundance of its main prey, the European rabbit, caused mainly by myxomatosis virus and rabbit haemorrhagic disease. At present, only two Iberian lynx populations persist in the wild compared with nine in the 1990s.

Over €90 million has been spent since 1994 to mitigate the extinction risk of this charismatic animal, mainly through habitat management, reduction of human-caused mortality and, more recently, translocation. Although lynx abundance might have increased in the last ten years in response to intensive management, a new study published in Nature Climate Change warns that the ongoing conservation strategies could buy just a few decades before the species goes extinct.

The study led by Damien Fordham from The Environment Institute (The University of Adelaide) and Miguel Araújo from the Integrative Biogeography and Global Change Group (Spanish Research Council) shows that climate change could lead to a rapid and severe decrease in lynx abundance in coming decades, and probably result in its extinction in the wild within 50 years. Current management efforts could be futile if they do not take into account the combined effects of climate change, land use and prey abundance on population dynamics of the Iberian Lynx.

Read the rest of this entry »





No need for disease

7 01 2013

dead or alive thylacineIt’s human nature to abhor admitting an error, and I’d wager that it’s even harder for the average person (psycho- and sociopaths perhaps excepted) to admit being a bastard responsible for the demise of someone, or something else. Examples abound. Think of much of society’s unwillingness to accept responsibility for global climate disruption (how could my trips to work and occasional holiday flight be killing people on the other side of the planet?). Or, how about fishers refusing to believe that they could be responsible for reductions in fish stocks? After all, killing fish couldn’t possibly …er, kill fish? Another one is that bastion of reverse racism maintaining that ancient or traditionally living peoples (‘noble savages’) could never have wiped out other species.

If you’re a rational person driven by evidence rather than hearsay, vested interest or faith, then the above examples probably sound ridiculous. But rest assured, millions of people adhere to these points of view because of the phenomenon mentioned in the first sentence above. With this background then, I introduce a paper that’s almost available online (i.e., we have the DOI, but the online version is yet to appear). Produced by our extremely clever post-doc, Tom Prowse, the paper is entitled: No need for disease: testing extinction hypotheses for the thylacine using multispecies metamodels, and will soon appear in Journal of Animal Ecology.

Of course, I am biased being a co-author, but I think this paper really demonstrates the amazing power of retrospective multi-species systems modelling to provide insight into phenomena that are impossible to test empirically – i.e., questions of prehistoric (and in some cases, even data-poor historic) ecological change. The megafauna die-off controversy is one we’ve covered before here on ConservationBytes.com, and this is a related issue with respect to a charismatic extinction in Australia’s recent history – the loss of the Tasmanian thylacine (‘tiger’, ‘wolf’ or whatever inappropriate eutherian epithet one unfortunately chooses to apply). Read the rest of this entry »





Individuals a population to conserve make

28 11 2012
Unique in its genus, the saiga antelope inhabits the steppes and semi-desert environments in two sub-species split between Kazakhstan (Saiga tatarica tatarica, ~ 80% of the individuals) and Mongolia (Saiga tatarica mongolica). Locals hunt them for their meat and the (attributed) medicinal properties of male horns. Like many ungulates, the population is sensitive to winter severity and summer drought (which signal seasonal migrations of herds up to 1000 individuals). But illegal poaching has reduced the species from > 1 million in the 1970s to ~ 50000 currently (see RT video). The species has gone extinct in China and Ukraine, and has been IUCN “Critically Endangered” from 2002. The photo shows a male in The Centre for Wild Animals, Kalmykia, Russia (courtesy of Pavel Sorokin).

In a planet approaching 7 billion people, individual identity for most of us goes largely unnoticed by the rest. However, individuals are important because each can promote changes at different scales of social organisation, from families through to associations, suburbs and countries. This is not only true for the human species, but for any species (1).

It is less than two decades since many ecologists started pondering the ways of applying the understanding of how individuals behave to the conservation of species (2-9), which some now refer to as ‘conservation behaviour’ (10, 11). The nexus seems straightforward. The decisions a bear or a shrimp make daily to feed, mate, move or shelter (i.e., their behaviour) affect their fitness (survival + fertility). Therefore, the sum of those decisions across all individuals in a population or species matters to the core themes handled by conservation biology for ensuring long-term population viability (12), i.e., counteracting anthropogenic impacts, and (with the distinction introduced by Cawley, 13) reversing population decline and avoiding population extinction.

To use behaviour in conservation implies that we can modify the behaviour of individuals to their own benefit (and mostly, to the species’ benefit) or define behavioural metrics that can be used as indicators of population threats. A main research area dealing with behavioural modification is that of anti-predator training of captive individuals prior to re-introduction. Laden with nuances, those training programs have yielded contrasting results across species, and have only tested a few instances of ‘success’ after release into the wild (14). For example, captive black-tailed prairie dogs (Cynomys ludovicianus) exposed to stuffed hawks, caged ferrets and rattlesnakes had higher post-release survival than untrained individuals in the grasslands of the North American Great Plains (15). A clear example of a threat metric is aberrant behaviour triggered by hunting. Eleanor Milner-Gulland et al. (16) have reported a 46 % reduction in fertility rates in the saiga antelope (Saiga tatarica) in Russia from 1993-2002. This species forms harems consisting of one alpha male and 12 to 30 females. Local communities have long hunted this species, but illegal poaching for horned males from the early 1990s (17) ultimately led to harems with a female surplus (with an average sex ratio up to 100 females per male!). In them, only a few dominant females seem to reproduce because they engage in aggressive displays that dissuade other females from accessing the males. Read the rest of this entry »





It couldn’t have been us!

29 05 2012

A few months ago I asked Chris Johnson of the University of Tasmania to put together a post on his recent Science paper regarding Australian megafaunal extinctions. It seems that it stirred, yet again, some controversy among those who refuse to accept (mainly archaeologists) that humans could have had anything to do with pre-European extinctions. Indeed, how could humans possibly have anything to do with extinctions?!

Like Corey, I am mainly interested in current environmental problems. But now and then I wade into the debate over the extinction of Australia’s Pleistocene megafauna [editor's note: Chris literally wrote the book on Australian mammal extinctions over the last 50,000 years], those huge animals that wandered over the Australian landscape until about 40,000 years ago.

This is an endlessly fascinating topic. The creatures were wonderful and bizarre – it’s great fun doing work that lets you think about marsupial lions, giant kangaroos, geese bigger than emus, echidnas the size of wombats, and the rest. The cause of their extinction is perhaps the biggest mystery, and the most vexed controversy, in the environmental history of Australia. And for reasons that I will explain in a minute, solving this mystery is profoundly important for our understanding of contemporary Australian ecology.

The latest bit of work on this is a paper that a group of us (including Corey’s close colleague, Barry Brook) published in Science. You can see it here (if you don’t have access to Science, email me for a copy). So far, research on this problem has concentrated on dating fossils to find out when megafauna species went extinct. Several recent studies have found evidence for extinction between 40,000 and 50,000 years ago, which is about when people first came to Australia. But the conclusion that people caused a mass extinction of megafauna has been strenuously criticised, because so far it is based on only a few species with good collections of dates. The critics argue that other species disappeared before humans arrived, maybe in an extended series of extinctions caused by something else, like a deteriorating climate.

This argument over fossils will be with us for a long time. Because finding and dating fossils is such hard, slow work, the fossil record will inevitably give a seriously incomplete picture of what happened. One way around this problem would be to analyse the fossil record using mathematical approaches that take into account the problem of incomplete sampling. Corey is lead author of a recent paper that introduced a great new set of tools for this, and we are part of a group that is currently assembling a complete database of all recent dates on Australian fossils so that we can analyse them using these tools. Stay tuned for the result. Read the rest of this entry »





Can Australia afford the dingo fence?

18 05 2012

I wrote this last night with Euan Ritchie of Deakin University in response to some pretty shoddy journalism that misrepresented my comments (and Euan’s work). Our article appeared first in The Conversation this morning (see original article).

We feel we have to set the record straight after some of our (Bradshaw’s) comments were taken grossly out of context, or not considered at all (Ritchie’s). A bubbling kerfuffle in the media over the last week compels us to establish some facts about dingoes in Australia, and more importantly, about how we as a nation choose to manage them.

A small article in the News Ltd. Adelaide Advertiser appeared on 11 May in which one of us (Bradshaw) was quoted as advocating the removal of the dingo fence because it was not “cost effective” (sic). Despite nearly 20 minutes on the telephone explaining to the paper the complexities of feral animal management, the role of dingoes in suppressing feral predators, and the “costs” associated with biodiversity enhancement and feral control, there wasn’t a single mention of any of this background or justification.

Another News Ltd. article denouncing Ritchie’s work on the role of predators in Australian ecosystems appeared in The Weekly Times the day before, to which Ritchie responded in full.

So it’s damage control, and mainly because we want to state categorically that our opinion is ours alone, and not that of our respective universities, schools, institutes or even Biosecurity SA (which some have claimed or insinuated, falsely, that we represent). Biosecurity SA is responsible for, inter alia, the dingo fence in South Australia. Although our opinions differ on its role, we are deeply impressed, grateful and supportive of their work in defending us from biological problems. Read the rest of this entry »





The wounded soldiers of biodiversity

10 04 2012

Here’s another great post from Salvador Herrando-Pérez. It is interesting that he’s chosen an example species that was once (a long, long time ago in a galaxy far, far away) of great interest to me (caribou – see ancient papers a, b, c, d). But that is another story. Take it away, Salva.

 

Figure 1. Caribou (reindeer) are ungulates weighing up to ~ 100 kg. They live in tundra and taiga in Finland, Greenland, Finland, Norway, Mongolia, Russia, Canada and USA (extinct in Sweden). The species is globally stable (‘Least Concern’, IUCN Red List), but the subspecies of woodland caribou (Rangifer tarandus caribou) is threatened in North America. Schneider and colleagues’ 7 study encompasses ~ 3,000 individuals in 12 herds (75 to 450 individuals per herd), occupying ~ 100.000 km2 of conifer forest and peatland (3,000 to 19,000 km2 per herd). Two ecotypes are recognized regionally22, namely migratory mountain herds (mostly from mountains and foothills in west-central Alberta), and non-migratory boreal herds (mostly from peatlands in central and northern Alberta). The photo shows a group of caribous grazing on subalpine vegetation from Tonquin Valley, Jasper National Park (Alberta, Canada). Photo courtesy of Saakje Hazenberg.

As conservation biology keeps incorporating management and economical principles from other disciplines, it stumbles with paradoxes such that investing on the most threatened components of biodiversity might in turn jeopardize the entire assets of biodiversity.

At the end of 2011, newspapers and TVs echoed an IUCN report cataloguing as ‘extinct’ or ‘near extinct’ several subspecies of rhinos in Asia and Africa. To many, such news might have invoked the topic: “how badly governments do to protect the environment”. However if, to avoid those extinctions, politicians had to deviate funds from other activities, what thoughts would come to the mind of workers whose salaries had to be frozen, school directors whose classroom-roof leakages could not be repaired (e.g., last winter at my niece’s school in Spain), colonels whose last acquisition of ultramodern tanks had to be delayed, or our city council’s department who had to cancel Sting’s next performance.

Thus, there are three unquestionable facts regarding species conservation:

  1. the protection of species costs money;
  2. governments and environmental organisations have limited budgets for a range of activities they deem necessary; and
  3. our way of conserving nature is failing because, despite increasing public/private support and awareness, the rate of destruction of biodiversity is not decelerating1,2.

One of the modern debates among conservationists pivots around how to use resources efficiently3-6. Schneider and colleagues7 have dealt with this question for woodland caribou (Rangifer tarandus) in Canada. A total of 18 populations of this ungulate persist in the Canadian province of Alberta, all undergoing demographic declines due to mining extractions (oil, gas and bitumen), logging and wolf predation. The species is listed as ‘threatened’ regionally and nationally. The Alberta Caribou Recovery Plan (2004-2014) is attempting to protect all herds. Under such a framework, Schneider et al.7 predicted that woodland caribou would be regionally extirpated in less than a century.

Furthermore, they estimated the costs of making each herd viable (Fig. 1), with a triple revelation. To save all herds from extinction would need ~ CA$150,000 million (beyond the available budget). The most threatened herds are among the most expensive to protect (within present management approach). Some herds would be secured through modest investment for two decades. Overall, their study suggests that Alberta’s woodland caribou would be eligible for triage, i.e., at the subpopulation level8. Read the rest of this entry »





Eat a feral a week

22 03 2012

© Y. Sugiura

Just a quick post this week about something I’ve been contemplating for a while.

What if every Australian pledged to eat a feral animal a week?

Yes, I know that it’s a bit out of the pitch, and I’m sure not everyone would do it. Nor would it be physically possible for one person to eat an entire camel, buffalo or deer in a week – but hopefully you get the picture.

Why propose this? Australia is quite over-run with feral animals. Some quick stats:

Now we have, of course, many other ferals (cats, rats, foxes, mice), but I don’t think too many people would want to eat them. I have personally eaten feral pigs, camels, buffalo, goats, and red, fallow and sambar deer, mostly from my own research trips or from friends who hunt. Read the rest of this entry »





When did it go extinct?

11 01 2012

It was bound to happen. After years of successful avoidance I have finally succumbed to the dark side: palaeo-ecology.

I suppose the delve from historical/modern ecology into prehistory was inevitable given (a) my long-term association with brain-the-size-of-a-planet Barry Brook (who, incidentally, has reinvented his research career many times) and (b) there is no logic to contend that palaeo extinction patterns differ in any meaningful way from modern biodiversity extinctions (except, of course, that the latter are caused mainly by human endeavour).

So while the last, fleeting days of my holiday break accelerate worringly toward office-incarceration next week, I take this moment to present a brand-new paper of ours that has just come out online in (wait for it) Quaternary Science Reviews entitled Robust estimates of extinction time in the geological record.

Let me explain my reasons for this strange departure.

It all started after a few drinks (doesn’t it always) with Alan Cooper, Chris Turney and Barry Brook when we were discussing the uncertainties associated with the timing of megafauna extinctions – you might be aware that traditionally there have been two schools of thought on late-Pleistocene extinction pulses: (1) those who think there were mainly caused by massive climate shifts not to dissimilar to what we are experiencing now and (2) those who believe that the arrival of humans into naïve regions lead to a ‘blitzkrieg‘ of hunting and overkill. Rarely do adherents of each stance agree (and sometimes, the ‘debate’ can get ugly given the political incorrectness of inferring that prehistoric peoples were as destructive as we are today – cf. the concept of the ‘noble savage‘). Read the rest of this entry »





Sustainable kangaroo harvests

10 11 2011

When I first started this blog back in 2008, I extolled the conservation virtues of eating kangaroos over cattle and sheep. Now I want to put my academic money where my mouth is, and do some kangaroo harvest research.

Thanks to the South Australia Department of Environment and Natural Resources  (DENR) and the commercial kangaroo harvest industry, in conjunction with the University of Adelaide, I’m pleased to announce a new scholarship for a PhD candidate to work on a project entitled Optimal survey and harvest models for South Australian macropods based at the University of Adelaide’s School of Earth and Environmental Sciences.

DENR is custodian of a long-term macropod database derived from the State’s management of the commercial kangaroo harvest industry. The dataset entails aerial survey data for most of the State from 1978 to present, annual population estimates, quotas and harvests for three species: red kangaroo (Macropus rufus), western grey kangaroo (Macropus fuliginosus), and the euro (Macropus robustus erubescens). Read the rest of this entry »





Where the sick buffalo roam

28 10 2011

It’s been some time coming, but today I’m proud to announce a new paper of ours that has just come out in Journal of Applied Ecology. While not strictly a conservation paper, it does provide some novel tools for modelling populations of threatened species in ways not available before.

The Genesis

A few years ago, a few of us (Bob LacyPhil Miller and JP Pollak of Vortex fame, Barry Brook, and a few others) got together in a little room at the Brookfield Zoo in the suburban sprawl of Chicago to have a crack at some new modelling approaches the Vortex crew had recently designed. The original results were pleasing, so we had a follow-up meeting last year (thanks to a few generous Zoo benefactors) and added a few post-docs and students to the mix (Damien FordhamClive McMahon, Tom Prowse, Mike Watts, Michelle Verant). The great population modeller Resit Akçakaya also came along to assist and talk about linkages with RAMAS.

Out of that particular meeting a series of projects was spawned, and one of those has now been published online: Novel coupling of individual-based epidemiological and demographic models predicts realistic dynamics of tuberculosis in alien buffalo.

The Coupling

So what’s so novel about modelling disease in buffalo, and why would one care? Well, here’s the interesting part. The buffalo-tuberculosis example was a great way to examine just how well a new suite of models – and their command-centre module – predicted disease dynamics in a wild population. The individual-based population modelling software Vortex has been around for some time, and is now particularly powerful for predicting the extinction risk of small populations; the newest addition to the Vortex family, called Outbreak, is also an individual-based epidemiological model that allows a population of individuals exposed to a pathogen to progress over time (e.g., from susceptible, exposed, infectious, recovered/dead). Read the rest of this entry »





No substitute for primary forest

15 09 2011

© Romulo Fotos http://goo.gl/CrAsE

A little over five years ago, a controversial and spectacularly erroneous paper appeared in the tropical ecology journal Biotropica, the flagship journal of the Association for Tropical Biology and Conservation. Now, I’m normally a fan of Biotropica (I have both published there several times and acted as a Subject Editor for several years), but we couldn’t let that paper’s conclusions go unchallenged.

That paper was ‘The future of tropical forest species‘ by Joseph Wright and Helene Muller-Landau, which essentially concluded that the severe deforestation and degradation of tropical forests was not as big a deal as nearly all the rest of the conservation biology community had concluded (remind you of climate change at all?), and that regenerating, degraded and secondary forests would suffice to preserve the enormity and majority of dependent tropical biodiversity.

What rubbish.

Our response, and those of many others (including from Toby Gardner and colleagues and William Laurance), were fast and furious, essentially destroying the argument so utterly that I think most people merely moved on. We know for a fact that tropical biodiversity is waning rapidly, and in many parts of the world, it is absolutely [insert expletive here]. However, the argument has reared its ugly head again and again over the intervening years, so it’s high time we bury this particular nonsense once and for all.

In fact, a few anecdotes are worthy of mention here. Navjot once told me one story about the time when both he and Wright were invited to the same symposium around the time of the initial dust-up in Biotropica. Being Navjot, he tore off strips from Wright in public for his outrageous and unsubstantiated claims – something to which Wright didn’t take too kindly.  On the way home, the two shared the same flight, and apparently Wright refused to acknowledge Navjot’s existence and only glared looks that could kill (hang on – maybe that had something to do with Navjot’s recent and untimely death? Who knows?). Similar public stoushes have been chronicled between Wright and Bill Laurance.

Back to the story. I recall a particular coffee discussion at the National University of Singapore between Navjot Sodhi (may his legacy endure), Barry Brook and me some time later where we planned the idea of a large meta-analysis to compare degraded and ‘primary’ (not overly disturbed) forests. The ideas were fairly fuzzy back then, but Navjot didn’t drop the ball for a moment. He immediately went out and got Tien Ming Lee and his new PhD student, Luke Gibson, to start compiling the necessary studies. It was a thankless job that took several years.

However, the fruits of that labour have now just been published in Nature: ‘Primary forests are irreplaceable for sustaining tropical biodiversity‘, led by Luke and Tien Ming, along with Lian Pin Koh, Barry Brook, Toby Gardner, Jos Barlow, Carlos Peres, me, Bill Laurance, Tom Lovejoy and of course, Navjot Sodhi [side note: Navjot died during the review and didn't survive to hear the good news that the paper was finally accepted].

Using data from 138 studies from Asia, South America and Africa comprising 2220 pair-wise comparisons of biodiversity ‘values’ between forests that had undergone some sort of disturbance (everything from selective logging through to regenerating pasture) and adjacent primary forests, we can now hammer the final nails into the coffin containing the putrid remains of Wright and Muller-Landau’s assertion – there is no substitute for primary forest. Read the rest of this entry »





Species’ Ability to Forestall Extinction – AudioBoo

8 04 2011

Here’s a little interview I just did on the SAFE index with ABC AM:


Not a bad job, really.

And here’s another one from Radio New Zealand:


CJA Bradshaw





S.A.F.E. = Species Ability to Forestall Extinction

8 01 2011

Note: I’ve just rehashed this post (30/03/2011) because the paper is now available online (see comment stream). Stay tuned for the media release next week. – CJAB

I’ve been more or less underground for the last 3 weeks. It has been a wonderful break (mostly) from the normally hectic pace of academic life. Thanks for all those who remain despite the recent silence.

© Ezprezzo.com

But I’m back now with a post about a paper we’ve just had accepted in Frontiers in Ecology and Environment. In my opinion it’s a leap forward in how we measure relative threat risk among species, despite some criticism.

I’ve written in past posts about the ‘magic’ minimum number of individuals that should be in a population to reduce the chance of extinction from random events. The so-called ‘minimum viable population (MVP) size’ is basically the abundance of a (connected) population below which random events take over from factors causing sustained declines (Caughley’s distinction between the ‘declining’ and ‘small’ population paradigms).

Up until the last few years, the MVP size was considered to be a population- or species-specific value, and it required very detailed demographic, genetic and biogeographical data to estimate – not something that biologists tend to have at their fingertips for most high-risk species. However, several papers published by our group (Minimum viable population size and global extinction risk are unrelated, Minimum viable population size: a meta-analysis of 30 years of published estimates and Pragmatic population viability targets in a rapidly changing world) have shown that there is in fact little variation in this number among the best-studied species; both demographic and genetic data support a number of around 5000 to avoid crossing the deadly threshold.

Now the fourth paper in this series has just been accepted (sorry, no link yet, but I’ll let you all know as soon as it is available), and it was organised and led by Reuben Clements, and co-written by me, Barry Brook and Bill Laurance.

The idea is fairly simple and it somewhat amazes me that it hasn’t been implemented before. The SAFE (Species Ability to Forestall Extinction) index is simply the distance a population is (in terms of abundance) from its MVP. In the absence of a species-specific value, we used the 5000-individual threshold. Thus, Read the rest of this entry »





More rain forest regeneration opportunities

5 10 2010

Last November I wrote about an exciting conservation research endeavour (see ‘How to restore a tropical rain forest‘)  in which I am involved called the Thiaki Rain Forest Regeneration Project taking place as we speak in the hinterland of north Queensland’s Atherton Tableland. I personally have done next to nothing on the project yet (UQ’s Margie Mayfield is leading the charge), so I can’t really update you on all the nitty-gritty of our progress. Regardless, I can say that some of the planting tests have been done, the species have been chosen and are growing happily in the nursery reading for planting in January 2011, and the baseline biodiversity assessments are well under way.

Well, prior to our Supercharge Your Science extravaganza in Cairns and Townsville a few weeks ago, I visited Penny & Noel at Thiaki for a catch up, a discussion of what’s been happening and what’s about to happen. It was a great weekend (the family came along too) with good food, wine, ticks and leeches (biodiversity in action), and I’m getting more and more excited about what this project will deliver over the coming years.

In the meantime, a couple of ‘opportunities’ have arisen; in other words – we need some good PhD students to tackle some outstanding issues with the project. Read the rest of this entry »





Humans 1, Environment 0

27 09 2010

© flickr.com/photos/singapore2010

While travelling to our Supercharge Your Science workshop in Cairns and Townsville last week (which, by the way, went off really well and the punters gave us the thumbs up – stay tuned for more Supercharge activities at a university near you…), I stumbled across an article in the Sydney Morning Herald about the state of Australia.

That Commonwealth purveyor of numbers, the Australian Bureau of Statistics (ABS), put together a nice little summary of various measures of wealth, health, politics and environment and their trends over the last decade. The resulting Measures of Australia’s Progress is an interesting read indeed. I felt the simple newspaper article didn’t do the environmental components justice, so I summarise the salient points below and give you my tuppence as well. Read the rest of this entry »








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