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 »





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 »





Sink to source – the loss of biodiversity’s greatest ecosystem service

29 02 2012

I’ve mentioned this idea before, but it’s nice when some real data support a prediction (no matter how gloomy that prediction might have been). It’s what drives scientists toward discovery (or at least, it’s what I find particularly appealing about my job).

Several years ago, my colleagues (Navjot Sodhi† and Ian Warkentin) and I wrote a major review in TREE about the fate of the world’s ‘second’ lung of the planet, the great boreal forests of Russia, Canada & Scandinavia. We discussed how fragmentation was increasing at an alarming rate, and that although most species there are still relatively intact, we stand to lose a lot of its biodiversity if we don’t halt the fragmenting processes soon. We wrote more on the subject in a paper to appear imminently in Biological Conservation.

Another component though that we raised in the TREE paper was the boreal forests were very much in danger of turning into a net carbon producer. You see, the ‘lung’ analogy is very pertinent because on average, the growth of the massive expanse of the vegetation in the forest generally takes up much more atmospheric carbon that it exudes through decay and burning (for as we all know, plants take up carbon dioxide to produce sugars during photosynthesis, and produce oxygen as a ‘waste’ product). However, as we fragment, cut down and burn the forest, it can end up producing more than it takes up (i.e., turning from a ‘sink’ to a ‘source’). We highlighted several studies indicating how insect outbreaks and human-exacerbated fire intensities and frequencies could conceivably do this.

Now Zhihai Ma and colleagues have just compiled a paper in PNAS indicating that the danger is well on the way to becoming reality in Canada. The paper entitled Regional drought-induced reduction in the biomass carbon sink of Canada’s boreal forests reports the results from 96 long-term permanent sampling plots spread right across southern Canada – from British Columbia in the far west, to Newfoundland in the far east. Read the rest of this entry »





1 million hectares annually – the forest destruction of Indonesia

30 09 2011

© A. Kenyon http://goo.gl/UpG3m

Bill Laurance wrote a compelling and very dour piece in The Conversation this week. He asked for some ‘link love’, so I decided to reproduce the article here for ConservationBytes.com readers. Full credit to Bill and The Conversation, of course.

What comes to mind when you think of Indonesia?

For biologists like myself, Australia’s northern neighbour provokes visions of ancient rainforests being razed by slash-and-burn farmers, and endangered tigers and orangutans fleeing from growling bulldozers.

This reality is true, but there is also hope on the horizon.

Indonesia is a vast, sprawling nation, spanning some 17,000 islands. Among these are Java, Sumatra, half of New Guinea and much of Borneo.

Some of the planet’s most biologically rich and most endangered real estate is found on this archipelago.

Today, Indonesia is losing around 1.1 million hectares of forest annually. That’s an area a third the size of Belgium, bigger than Australia’s Wet Tropics World Heritage Area.

With forest loss now slowing in Brazil, Indonesia has the dubious distinction of being the world’s deforestation “leader”. No nation is destroying its forests faster.

In Sumatra, where I visited recently, the world’s biggest paper-pulp corporations are chopping down hundreds of thousands of hectares of native rainforest to make paper and cardboard.

Some of these corporations also fund aggressive lobbyists, such as World Growth in Washington DC [CJA Bradshaw’s note: see our piece on one particular patron of WG – Alan Oxley], to combat their critics and dissuade major retail chains from dropping their products. Read the rest of this entry »





Know thy threat

9 06 2011

Here’s another great guest post by Megan Evans of UQ – her previous post on resolving the environmentalist’s paradox was a real hit, so I hope you enjoy this one too.

The reasons for the decline of Australia’s unique biodiversity are many, and most are well known. Clearing of vegetation for urban and agricultural land uses, introduced species and changed fire patterns are regularly cited in State of the Environment reports, recovery plans and published studies as major threats to biodiversity. But, while these threats are widely acknowledged, little has been done to quantify them in terms of the proportion of species affected, or their spatial extent at a national, state or local scale. To understand why such information on threats may be useful, consider for instance how resources are allocated in public health care1.

Threat knowledge

Conditions such as cancer, heart disease and mental health are regarded as National Health Priority Areas in Australia, and have been given special attention when prioritising funds since the late 1980s. The burden of disease in these priority areas are quantified according to the incidence or prevalence of disease or condition, and its social and economic costs. Estimates of burden of disease and their geographic distribution (often according to local government areas) can assist in communicating broad trends in disease burden, but also in prioritising efforts to achieve the best outcomes for public health. An approach similar to that used in healthcare could help to identify priorities for biodiversity conservation – using information on the species which are impacted by key threats, the spatial distributions of species and threats, and the costs of implementing specific management actions to address these threats. Read the rest of this entry »





Global erosion of ecosystem services

14 09 2010

A few months ago I was asked to give a lecture about erosion of ecosystem services to students in the University of Adelaide‘s Issues in Sustainable Environments unit. I gave that lecture last week and just uploaded a slidecast of the presentation (with audio) today.

I’ve reproduced the lecture here for your viewing pleasure. I hope you find the 45-minute presentation useful. Note that the first few minutes cover me referring to the Biodiversity film short that I posted not too long ago.

CJA Bradshaw





Biodiversity SNAFU in Australia’s Jewel

16 06 2010

I’ve covered this sad state of affairs and one of Australia’s more notable biodiversity embarrassments over the last year (see Shocking continued loss of Australian mammals and Can we solve Australia’s mammal extinction crisis?), and now the most empirical demonstration of this is now published.

The biodiversity guru of Australia’s tropical north, John Woinarksi, has just published the definitive demonstration of the magnitude of mammal declines in Kakadu National Park (Australia’s largest national park, World Heritage Area, emblem of ‘co-management’ and supposed biodiversity and cultural jewel in Australia’s conservation crown). According to Woinarski and colleagues, most of those qualifiers are rubbish.

The paper published in Wildlife Research is entitled Monitoring indicates rapid and severe decline of native small mammals in Kakadu National Park, northern Australia and it concludes:

The native mammal fauna of Kakadu National Park is in rapid and severe decline. The cause(s) of this decline are not entirely clear, and may vary among species. The most plausible causes are too frequent fire, predation by feral cats and invasion by cane toads (affecting particularly one native mammal species).

I’ve done quite a bit of work in Kakadu myself, and the one thing that hits you every time you travel through it is the lack of visible wildlife. Sure, you’ll see horses, pigs and buffalo, as well as cane toads and cats, but getting a glimpse of anything native, from Conilurus to Varanus, and you’d consider yourself extremely lucky.

We’ve written a lot about the feral animal problem in Kakadu and even developed software tools to assist in density-reduction programmes. It doesn’t appear that anyone is listening.

Another gob-smacking vista you’ll get when travelling through Kakadu any time from April to December is that it’s either been burnt, actively burning or targeted for burning. They burn the shit out of the place every year. No wonder the native mammals are having such a hard time.

Combine all this with the dysfunctional management arrangement, and you cease to have a National Park. Kakadu is now a lifeless shell that does precious little for conservation of biodiversity (and 3 of the 5 criteria it had to satisfy to become a World Heritage Area are specifically related to natural resource ‘values’). I say, delist Kakadu now and let’s stop fooling ourselves.

Ok, back from the rant. Woinarski and others superimposed a mammal monitoring programme over top a fire-regime experiment for vegetation. Although they couldn’t sample every plot every season, they staggered the sampling to cover the area as best they could over the 13 years of monitoring (1996-2009). What they observed was staggering. Read the rest of this entry »





Global rates of forest loss – everyone’s a bastard

29 04 2010

© A. Hesse

I’ve written rather a lot about rates of forest loss around the world, including accumulated estimates of tropical forest loss and increasing fragmentation/loss in the boreal forest (see Bradshaw et al. 2009 Front Ecol Evol & Bradshaw et al. 2009 Trends Ecol Evol). For the tropics in particular, we used the index that an area of rain forest about the size of Bangladesh (> 15 million hectares) was disappearing each year, and in Russia alone, annual decline in forest area averaged 1.1 million hectares between 1988 and 1993. Mind boggling, really.

But some of these estimates were a bit old, relied on some imprecise satellite data, and didn’t differentiate forest types well. In addition, many have questioned whether the rates are continuing and which countries are being naughty or nice with respect to forest conservation.

It was great therefore when I came across a new paper in PNAS by Hansen & colleagues entitled Quantification of global gross forest cover loss because it answered many of the latter questions.

Part of the problem in assessing worldwide forest cover loss in the past was the expense of satellite imagery, access problems, data storage and processing issues. Happily, new satellite streams and easing of access has rectified many of these limitations. Hansen & colleagues took advantage of data from the MODIS sensor to create a stratification for forest cover loss. They then used the Landsat ETM+ sensor as the primary data for quantifying gross forest cover loss for the entire planet from 2000 to 2005. They defined ‘forest cover’ as “… 25% or greater canopy closure at the Landsat pixel scale (30-m × 30-m spatial resolution) for trees > 5 m in height”.

For your reading pleasure (and conservation horror), the salient features were: Read the rest of this entry »





December Issue of Conservation Letters

11 12 2009

Gemsbok (Oryx gazella) in Namibia

Another great line-up in Conservation Letters‘ last issue for 2009. For full access, click here.





Can we solve Australia’s mammal extinction crisis?

3 09 2009

© F. O'Connor

© F. O'Connor

This ‘In DepthScience Opinion piece from the ABC couldn’t have come at a better time. Written by Ian Gordon of the CSIRO, this opinion piece was written off the back of the special session on mammalian extinctions held at the recent International Congress of Ecology in Brisbane. Three previous ConservationBytes.com blogs in August (here, here and here) were devoted to specific talks at the Congress, including one about John Woinarksi’s gloomy tale of dwindling mammal populations in the Top End (which is especially frightening considering its also going on in our so-called ‘protected’ areas such as Kakadu, Litchfield and Garig Gunak Barlu National Parks!).

So, I recommend you have a read of my blog post on the shocking continued loss of Australian mammals, then read Ian’s piece copied below. Bottom lines – stop burning the shit out of our forests and encourage dingo population recovery and expansion.

Australia leads the world in mammal extinctions.

Over the last two hundred years 22 mammal species have become extinct, and over 100 are now on the threatened and endangered species list, compiled as part of the federal government’s Environment Protection and Biodiversity Conservation Act.

Evidence suggests Australia is on the cusp of another wave of mammal extinctions with a reduction in the abundance of some species and alarmingly, their range.

This is undoubtedly one of the major biodiversity conservation issues affecting Australia. It’s crucial we focus on the management solutions required to stop these species falling into extinction.

A South American success story

Working as a zoologist has allowed me to be involved in projects across the globe, looking at species at risk of extinction due to over-exploitation by humans.

Earlier this year I edited a book on the South American vicuña‘s comeback from the brink of extinction. Once abundant in the Andes, this wild relative of the llama suffered a sharp population drop in the 1960s due to international demand for its fleece.

An international moratorium on the sale of vicuña fleece in 1969 saw populations recover enough by 1987 for Andean communities to be able to harvest the fibre in a sustainable way. Population numbers of vicuña have remained healthy ever since, making it one of the few success stories of wildlife conservation worldwide.

Australia’s mammal extinction crisis

However Australia’s medium-sized mammals have had to deal with a different range of issues to the vicuña: the introduction of feral animals, particularly cats and foxes; increased grazing pressure; altered fire regimes; the clearing of habitat for development and production; and now, the effects of climate change.

It isn’t that any of these pressures are particularly important by themselves, but the fact that many of them act in concert has had a significant impact on causing the crashes in population numbers, and increasing the risk of species becoming extinct.

For example, the crescent nailtail wallaby was once an abundant and widespread macropod of central and western Australia. The pressures of feral cats and foxes coupled with clearing for agriculture and grazing, and altered fire regimes pushed this little species over the edge and it is now classified as extinct.

The problem is also more far-reaching than we first assumed. Many people may think that animals are becoming extinct in the south of Australia where habitat destruction is quite evident.

But the populations of iconic species in the north of Australia such as the northern quoll, golden bandicoot and the Carpentarian rock-rat are also collapsing. In our lifetime populations of some species have greatly reduced in number, and others have completely disappeared in landscapes that are considered to be in excellent condition.

The golden bandicoot, listed as a vulnerable species, used to be found across much of the north of Australia. It is now only found in very small populations in the Northern Territory and on the isolated Burrow Island off the coast of Western Australia.

Time to bring back the dingo?

Further research on the impacts of fire, grazing, invasive species and climate change on Australian mammals would be extremely valuable, but ecologists recognise that crucial management decisions need to be made now.

We’ve found ourselves in a position where we have identified the threats to Australian mammal species and documented the loss of these species, the role of science must turn more directly to identifying the opportunities for assisting the survival of these mammals.

In August I chaired a panel with Professor Chris Johnson from James Cook University at the International Congress of Ecology, to discuss what management could be put in place now to help beleaguered populations of small mammals recover.

Johnson’s main focus is to bring back the top-order predator.

He believes there is now good evidence that a stable population of dingoes suppresses the numbers and activity of foxes and cats, and some other feral animal species as well.

He argues that the effect of using a top predator like the dingo to hold down populations of foxes and cats is that the total intensity of predation on smaller native mammals can be reduced.

Bringing back the dingo has many sheep and cattle farmers raising their eyebrows because the wild dogs are known to kill stock. But guardian sheepdogs can protect stock herds by fighting off dingoes if they come too close. This still allows the dingoes to have a beneficial effect in the ecosystem.

Current trials of Maremma dogs, a type of sheepdog, at Dunluce sheep station in northwest Queensland demonstrate that they can be effective dingo deterrents in a pastoral zone.

This is just one potential solution that may work in some areas. Reinstating mosaic fire regimes, where patches of land are burnt at different times to allow the land to recover in stages, and controlling grazing around sensitive habitat of endangered mammals are other potential solutions that are currently under trial in various parts of the country.

Working together

Even though science doesn’t have all the answers I believe that it is more important than ever for land managers and scientists to work together to put new management regimes on the ground.

Our scientific knowledge can provide guidelines for land managers to reduce the pressures on our biodiversity. Through monitoring how species and ecosystems respond to on-ground management we can then learn and adapt our advice to meet future challenges facing Australia’s threatened species.

We need to act now: the international community is watching Australia and we have an opportunity to show how we can apply science through collaborative agreements with land managers to reduce the threats and protect endangered species.

We’ll then be able to add Australian animals to the short list of species, like the vicuña, that have been brought back from the brink of extinction.

CJA Bradshaw

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl





Burning away ecological ignorance

24 08 2009

This is the last post from the 10th International Congress of Ecology (INTECOL) in Brisbane. I’ve just returned after a long, but good week.

fire

© ABC Landline

Following my last two posts (here and here) from INTECOL, I end with a post about the very final talk of the Congress by a very well-known conservation ecologist, Professor David Lindenmayer of the Australian National University. David is a prolific and highly respected ecologist specialising in long-term ecological studies measuring forest biodiversity change. What made this final talk so compelling (and compelling it had to be after 5 straight days of talks) was not that it was essentially his acceptance ‘speech’ for winning the Ecological Society of Australia‘s Australian Ecology Research Award (AERA), it was the personal side of his science that kept the audience rapt.

As many CB readers will know, Australia (the state of Victoria in particular) suffered earlier this year some of the worst forest fires on record. Many died and many millions in property were damaged. Since then, everyone from Germaine Greer to MP Wilson Tuckey has become a laughably unqualified fire expert, but few have sufficient knowledge or experience to prescribe the most parsimonious fire regime for Victoria’s wet temperate forests.

Now, I think David was unfortunate to lose either friends or family in those fires, and he’s been collecting biodiversity data there and studying the ecology of south Australian fires for over two decades. Suffice it to say, he probably knows what he’s talking about.

So when the baying hounds of public misunderstanding demand that the remaining bush fragments of Victorian forests be cleared to protect people and property (so-called ‘hazard-reduction burning’), I think we should listen instead to David Lindenmayers of this world.

David’s talk was about just this – how the fires are portrayed as the Apocalypse itself by the media, when in reality ecosystems generally bounce back very quickly. Indeed, even in some of the most heavily burnt sites, most of the standing carbon in the vegetation remains (despite appearances). He also explained that our knowledge of temperate fire regimes is rudimentary at best, and that available evidence from the Northern Hemisphere suggests that clearing forests actually can lead to a HIGHER fire proneness, intensity and frequency. He explained how the homogenisation of fire patterns destroy are weakening essential ecosystem functions, and that spatial and temporal fire patchiness is essential to maintain ecosystems and the people living in them.

In summary, we have failed to learn lessons from northern Australia about buggering up the natural fire regime (see previous post). We as a society fall victim to sensationalist and uninformed media reports and develop ill-advised, knee-jerk policies as a result. Ecological considerations for our own welfare have been overlooked too long. It’s time politicians stop fuelling the fires of public ignorance and listen to the ecologists out there who know a thing or two about complex ecosystem structure and the disturbance regimes that create them.

Thanks, David, for a sobering reminder of the importance of our work.

CJA Bradshaw

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl





Shocking continued loss of Australian mammals

21 08 2009

thylacineAs CB readers know, I’m in Brisbane this week for the 10th International Congress of Ecology (INTECOL). My last post was on a great plenary talk by biodiversity guru, Kevin Gaston of the University of Sheffield, and I’ve got one more before heading back to Adelaide tomorrow.

Today, the last day of INTECOL talks, brought together some great conservation minds in a session in which I was honoured to participate. I spoke on extinction synergies, but I think John Woinarski of the Northern Territory Government stole the show.

I used to live in the NT and have seen John speak many times; however, this was one of the best and most sobering of his talks I’ve seen yet.

In a nutshell, we are STILL experiencing a colossal decline in our mammals. I think many might know that Australia is the WORST country in the world for mammal extinctions already – even more gut-wrenching when you consider that our closest competitors are small islands that have a completely different set of threats. However, many don’t know (and this is John’s point), that we are still losing populations at an outrageous rate.

John’s been working on everything from Conilurus to quolls in the central and northern parts of Australia for over 20 years, and he’s got some of the best data around. Without fail, almost every remaining native small mammal population is in decline, even to the point of local extirpation in over 50 % of all his monitoring sites (and there are a lot of monitoring sites).

If that isn’t worrying enough, much of his data are collected in some of our biggest national parks (e.g., Kakadu National Park) – this basically means that despite restricting habitat loss (our greatest driver of extinction), mammal populations are still in ever-increasing states of buggery.

So, what are the causes? Anyone who’s been to Kakadu National Park, or (even luckier) has been to Arnhem Land, know that we’re literally burning the shit out of these places. Sure, fire is an integral part of northern Australian ecology, but the pervasive paradigm – unless-it’s-burnt-every-year-it’s-bad credence – means that nothing ever has a chance to come back after a population crash caused by a one-off fire.

Sure, things like cane toads and other feral animals might play a role, but it’s the ridiculous burning regime we’ve adopted that’s destroying our already depleted and unique mammalian species assemblage. Unless we reverse this trend NOW, we’ll have more or less condemned our one-of-a-kind mammals to extinction. As an Australian, can you live with that?

A stark reminder of how ridiculous the situation has become, esteemed Professor William Bond of South Africa stated in the question period after John’s talk (I paraphrase):

“When you arrive in Australia, you are bombarded with slogans of sporting victories, great food and fantastic wine [all true], but no one tells you of the biodiversity tragedy that has, and is continuing, to happen in Australia. In Africa, we have managed to convince people to conserve elephants that destroy their crops and kill their families – why can’t Australians realise their are destroying their very heritage? What are you doing to stop the carnage?”

I have no answer. Sorry, William. Sorry, John. Sorry, Australia.

CJA Bradshaw

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl





Fragmen borealis: degradation of the world’s last great forest

12 08 2009
© energyportal.eu

© energyportal.eu

I have the dubious pleasure today of introducing a recently published paper of ours that was at the same time both intellectually stimulating and demoralising to write. I will make no apologies for becoming emotionally involved in the scientific issues about which my colleagues and I write (as long as I can maintain with absolute sincerity that the data used and conclusions drawn are as objectively presented as I am capable), and this paper probably epitomises that stance more than most I’ve written during my career.

The topic is especially important to me because of its subtle, yet potentially disastrous consequences for biodiversity and climate change. It’s also a personal issue because it’s happening in a place I used to (many, many years ago) call home.

Despite comprising about a third of the world’s entire forested area and harbouring some of the lowest human densities anywhere, the great boreal forest that stretches across Alaska, Canada, Scandinavia and a huge chunk of Russia is under severe threat.

Surprised that we’re not talking about tropical deforestation for once? Surprised that so-called ‘developed’ nations are pilfering the last great carbon sink and biodiversity haven left on the planet? If you have read any of the posts on this blog, you probably shouldn’t be.

The paper today appeared online in Trends in Ecology and Evolution and is entitled Urgent preservation of boreal carbon stocks and biodiversity (by CJA Bradshaw, IG Warkentin & NS Sodhi). It’s essentially a review of the status of the boreal forest from a biodiversity perspective, and includes a detailed assessment of the degree of its fragmentation, species threat, climate- and human-influenced disturbance regime, and its carbon sequestration/emission status. I’ll summarise some of the main findings below:

borealfire

© NASA

  • Russia contains ~53 % of the boreal forest, followed by Canada (25 %), USA (18 %, mostly in Alaska), Sweden (2 %) and Finland and Norway (~1 % each); there are small areas of boreal forest in northern China and Mongolia.
  • Fire is the main driver of change in the boreal forest. Although clearing for logging and mining abounds, it pales in comparison to the massive driver that is fire.
  • There is evidence that climate change is increasing the frequency and possibly extent of fires in the boreal zone. That said, most fires are started by humans, and this is particularly the case in the largest expanse in Russia (in Russia alone, 7.5 and 14.5 million hectares burnt in 2002 and 2003, respectively).
  • While few countries report an overall change in boreal forest extent, the degree of fragmentation and ‘quality’ is declining – only about 40 % of the total forested area is considered ‘intact’ (defined here as areas ≥ 500 km2, internally undivided by things such as roads, and with linear dimensions ≥ 10 km).
  • Russian boreal forest is the most degraded and least ‘intact’, and has suffered the greatest decline in the last few decades compared to other boreal countries.
  • Boreal countries have only < 10 % of their forests protected from wood exploitation, except Sweden where it’s about 20 %.
  • There are over 20000 species described in the boreal forest – a number much less than that estimated for tropical forests even of much smaller size.
  • 94 % of the 348 IUCN Red Listed boreal species are considered to be threatened with extinction, but other estimates from local assessments compiled together in 2000 (the United Nations’ Temperate and Boreal Forest Resources Assessment) place the percentages of threatened species up to 46 % for some taxa in some countries (e.g., mosses in Sweden). The latter assessment placed the Fennoscandian countries as having the highest proportions of at-risk taxa (ferns, mosses, lichens, vascular plants, butterflies, birds, mammals and ‘other vertebrates’), with Sweden having the highest proportion in almost all categories.
  • Boreal forest ecosystems contain about 30 % of the terrestrial carbon stored on Earth (~ 550 Gigatonnes).
  • © BC Ministry For Range/L. Maclaughlan

    Warmer temperatures have predisposed coniferous forest in western Canada to a severe outbreak of mountain pine beetle (Dendroctonus ponderosae) extending over > 13 M ha. © BC Ministry For Range/L. Maclaughlan

  • Mass insect outbreaks killing millions of trees across the entire boreal region are on the rise.
  • Although considered in the past as a global carbon sink, recent disturbances (e.g., increasing fire and insect outbreak) and refinements of measurement mean that much of the area is probably a carbon source (at least, temporarily).
  • A single insect outbreak in western Canada earlier this decade thought to be the direct result of a warming planet contributed more carbon to the atmosphere than all of that country’s transport industry and fire-caused release combined.
  • Current timber harvest management is inadequately prepared to emulate natural fire regimes and account for shifting fire patterns with climate change.
  • No amount of timber management can offset the damage done by increasing fire – we must manage fire better to have any chance of saving the boreal forest as a carbon sink and biodiversity haven.

Those include the main take-home messages. I invite you to read the paper in full and contact us (the authors) if you have any questions.

CJA Bradshaw

Full reference: Bradshaw, CJA, IG Warkentin, NS Sodhi. 2009. Urgent preservation of boreal carbon stocks and biodiversity. Trends in Ecology and Evolution DOI: 10.1016/j.tree.2009.03.019

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl





Ray of conservation light for Borneo

25 07 2009

This was the most interesting 20 minutes I’ve spent in the last wee while.

Up until just now, I had never heard of Willie Smits or what he’s been doing in Indonesia. I’ve been fairly hard on Indonesia in some of my papers and blog posts because of the ecological tragedy taking place there. I’ve focussed on the immense rate and extent of deforestation, the oil palm explosion, peatland destruction and air pollution arising from runaway fires there – I have thus far ignored any real positives because I didn’t really believe there were any.

Then I saw Smits’ TED talk. Two words – very impressed. I usually enjoy and even barrack for TED talks, and this is no exception.

This man and his organisation have really been applying a great deal of the research mentioned on ConservationBytes.com, as well as collecting data proving beyond a shadow of a doubt that if you integrate people’s needs with those of biodiversity, you can restore not only entire ecosystems, you can make humans benefit immensely in the process. A chronic pessimist, I can scarcely believe it.

He talks about a whole-system approach where agriculture, full rain forest restoration, climate control, carbon sequestration, monitoring and local governance all work together to turn once bare, fire-prone, species-poor deforested grasslands into teaming jungles that support happy, healthy, wealthy and well-governed human communities. Please watch this.

Vodpod videos no longer available.

CJA Bradshaw

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl





Indonesia’s precious peatlands under oil palm fire

31 05 2009
© Cockroach Productions

© Cockroach Productions

A small opinion piece about to be published in Frontiers in Ecology and the Environment (June 2009 issue) discusses a major concern we (Lian Pin Koh, Rhett Butler and I) have with Indonesia’s decision to allow peatlands less than 3 m deep to be converted to oil palm. Is nothing immune to the spread of this crop (see previous posts here and here on oil palm plantations)?

Why is this such a big deal? Well, we list five main reasons why it’s a bad idea for Indonesia, the world in general and biodiversity:

  1. Peatlands are amazing carbon sinks, so their destruction necessarily equates to a large release of carbon into the atmosphere (Page et al. 2002)
  2. Tropical peatlands take a hell of a long time to generate – 100s to 1000s of years (Chimner and Ewel 2005)
  3. Tropical peatlands harbour a massive biodiversity, but they are still poorly described and their ecosystems only superficially understood
  4. The burning of peatlands to provide the conditions necessary to plant oil palm will contribute to the massive ‘haze’ problem in South East Asia (Lohman et al. 2007)
  5. The decision goes against the principles of ‘reducing carbon emissions from deforestation and forest degradation‘ (REDD), which means it will be more difficult to implement carbon trading schemes that intrinsically value intact forests

More detail can be found in the Write Back piece that will be published shortly in Frontiers in Ecology and the Environment. For more information on oil palm and its conservation implications, see the following:

CJA Bradshaw

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl





Moving forward with extinction risk predictions from climate change

15 10 2008

A little belated, but I thought this was worth mentioning for the Potential list…

182kydeee9pyxjpgOne from Keith and colleagues in Biology Letters entitled Predicting extinction risks under climate change: coupling stochastic population models with dynamic bioclimatic habitat models is a nice example of a way forward to predict the extremely complex array of ecological processes and patterns that may arise from rapid climate change.

One of the major problems with predicting how biodiversity might respond to climate change is the typical simplicity of single-species ‘envelope’ models – these models basically use tolerance limits (generally, physiological) or optimum conditions to predict how a species’ distribution might change. Unfortunately, this usually negates the complex dynamics of populations, the dispersal capacity of individuals, and interactions with other species that may all dominate possible responses. In other words, climatic envelope models may be way, way off (and probably vastly optimistic).

Keith and colleagues have brought us a step closer to better predictions of (and hopefully, better responses to) climate change effects on species. They linked a time series of habitat suitability models with spatially explicit stochastic population models to explore factors that influence the viability of plant species populations in South African fynbos, a global biodiversity hotspot. They discovered that complex interactions between life history, disturbance regimes and distribution patterns mediate species extinction risks under climate change.

Well done! Our next challenge is to incorporate multiple species’ interactions into such models (just to make them as mind-bogglingly complex as possible) to give us better approaches for managing our depauperate future.

CJA Bradshaw

Add to FacebookAdd to NewsvineAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to Ma.gnoliaAdd to TechnoratiAdd to Furl








%d bloggers like this: