Eye on the taiga

24 03 2014

boreal damageDun! Dun, dun, dun! Dun, dun, dun! Dun, dun, daaaaah!

I’ve waited nearly two years to do that, with possibly our best title yet for a peer-reviewed paper: Eye on the taiga: removing global policy impediments to safeguard the boreal forest (recently published online in Conservation Letters).

Of course, the paper has nothing to do with cheesy Eighties music, underdog boxers or even tigers, but it does highlight an important oversight in world carbon politics. The boreal forest (also known as taiga from the Russian) spans much of the land mass of the Northern Hemisphere and represents approximately one quarter of the entire planet’s forests. As a result, this massive forest contains more than 35% of all terrestrially bound carbon (below and above ground). One doesn’t require much more information to come to the conclusion that this massive second lung of the planet (considering the Amazon the first lung) is a vital component of the world’s carbon cycle, and temperate biodiversity.

The boreal forest has been largely expanding since the retreat of the glaciers following the Last Glacial Maximum about 20,000 years ago, which means that its slow progression northward has produced a net carbon sink (i.e., it takes up more atmospheric carbon that it releases from decomposition). However, recent evidence suggests that due to a combination of increased deforestation, fire from both human encroachment and climate change, mass outbreaks of tree-killing insects and permafrost melting, the boreal forest is tipping towards becoming a net carbon source (i.e., emitting more carbon into the atmosphere than it takes up from photosynthesis). This is not a good thing for the world’s carbon cycle, because it means yet another positive feedback that will exacerbate the rapid warming of the planet. Read the rest of this entry »





Shrinking global range projected for the world’s largest fish

7 08 2013
© W. Osborn (AIMS)

© W. Osborn (AIMS)

My recently finished PhD student, Ana Sequeira, has not only just had a superb paper just accepted in Global Change Biology, she’s recently been offered (and accepted) a postdoctoral position based at the University of Western Australia‘s Oceans Institute (in partnership with AIMS and CSIRO). As any supervisor, I’m certainly pleased when a student completes her PhD, but my pride as an academic papa truly soars when she gets her first job. Well done, Ana. This post by Ana is about her latest paper.

Following our previous whale shark work (see herehereherehere, here, here and here), especially the recent review where we inferred global connectivity and suggest possible pathways for their migration, we have now gone a step further and modelled the habitat suitability for the species at at global scale. This paper sets a nice scene regarding current habitat suitability, which also demonstrates the potential connectivity pathways we hypothesised previously. But the paper goes much further; we extend our predictions to a future scenario for 2070 when water temperatures are expected to increase on average by 2 °C.

Sequeira et al_GCB_Figure 3

Global predictions of current seasonal habitat suitability for whale sharks. Black triangles indicate known aggregation locations. Solid line delineates areas where habitat suitability > 0.1 was predicted.

Regarding the current range of whale sharks (i.e., its currently suitable habitat), we already know that whale sharks span latitudes between about 35 º North to South. We also know that this geographical range has been exceeded on several occasions. What we did not know was whether conditions were suitable enough for whale sharks to cross from the Indian Ocean to the Atlantic Ocean – in other words, whether they could travel between ocean basins south of South Africa. Our global model results demonstrate that suitable habitat in this region does exist at least during the summer, thus supporting our hypotheses regarding global connectivity!

It’s true that the extensive dataset we used (30 years’ worth of whale shark sightings collected by tuna purse seiners in the three major oceans – data provided by the IRD, IOTC and SPC) has many caveats (as do all opportunistically collected data), but we went to great trouble to deal with them in this paper (you can request a copy here or access it directly here). And the overall result: the current global habitat suitability for whale sharks does agree well with current locations of whale shark occurrence, with the exception of the Eastern Pacific for where we did not have enough data to validate. Read the rest of this entry »





A carbon economy can help save our species too

20 05 2013

money treeWe sent out this media release the other day, but it had pretty poor pick-up (are people sick of the carbon price wars?). Anyway, I thought it prudent to reprint here on CB.com.

Will Australia’s biodiversity benefit from the new carbon economy designed to reduce greenhouse gas emissions? Or will bio-‘perversities’ win the day?

“Cautious optimism” was the conclusion of Professor Corey Bradshaw, Director of Ecological Modelling at the University of Adelaide’s Environment Institute. He is lead author of a new paper published in the journal of Biological Conservation which reviewed the likely consequences of a carbon economy on conservation of Australian biodiversity.

“In most circumstances these two very important goals for Australia’s future – greenhouse gas emissions reduction and biodiversity conservation – are not mutually exclusive and could even boost each other,” Professor Bradshaw says.

“There are, however, many potential negative biodiversity outcomes if land management is not done with biodiversity in mind from the outset.”

The paper was contributed to by 30 Australian scientists from different backgrounds. They reviewed six areas where Australia’s Carbon Farming Initiative could have the greatest impact on biodiversity: environmental plantings; policies and practices to deal with native regrowth; fire management; agricultural practices; and feral animal control.

“The largest biodiversity ‘bang for our buck’ is likely to come from tree plantings,” says Professor Bradshaw. “But there are some potential and frightening ‘bioperversities’ as well. For example, we need to be careful not to plant just the fastest-growing, simplest and non-native species only to ‘farm’ carbon.

“Carbon plantings will only have real biodiversity value if they comprise appropriate native tree species and provide suitable habitats and resources for valued fauna. Such plantings could however risk severely altering local hydrology and reducing water availability.”

Professor Bradshaw says carefully managing regrowth of once-cleared areas could also produce a large carbon-sequestration and biodiversity benefit simultaneously. And carbon price-based modifications to agriculture that would benefit biodiversity included reductions in tillage frequency, livestock densities and fertiliser use, and retention and regeneration of native shrubs. Read the rest of this entry »





Brave new green world: biodiversity’s response to Australia’s carbon economy

12 03 2013

carbon farming 2I’ve had a busy weekend entertaining visiting colleagues and participating in WOMADelaide‘s first-ever ‘The Planet Talks‘. If you haven’t heard of WOMADelaide, you’re truly missing out in one of the best music festivals going (and this is from a decidedly non-festival-going sort). Planet Talks this year was a bit of an experiment after the only partially successful Earth Station festival held last year (it was well-attended, but apparently wasn’t as financially successful as they had hoped). So this year they mixed a bit of science with a bit of music – hence ‘Planet Talks’. Paul Ehrlich was one of the star attractions, and I had the honour of going onstage with him yesterday to discuss a little bit about human population growth and sustainability. It was also great to see Robyn Williams again. All the Talks were packed out – indeed, I was surprised they were so popular, especially in the 39-degree heat. Rob Brookman, WOMADelaide’s founder and principal organiser, told me afterward that they’d definitely be doing it again.

But my post really isn’t about WOMADelaide or The Planet Talks (even though I got the bonus of meeting one of my favourite latin bands, Novalima, creators of one of my favourite songs). It’s instead about a paper I heralded last year that’s finally been accepted.

In early 2012 at the Terrestrial Ecosystem Research Network (TERN) symposium in Adelaide, the Australian Centre for Ecological Analysis and Synthesis (ACEAS) put on what they called the ‘Grand Challenges’ workshop. I really didn’t get the joke at the time, but apparently the ‘grand challenge’ was locking 30 scientists with completely different backgrounds in a room for two days to see if they could do anything other than argue and bullshit. Well, we rose to that challenge and produced something that I think is rather useful.

I therefore proudly introduce the paper entitled Brave new green world: consequences of a carbon economy for the conservation of Australian biodiversity just accepted in Biological Conservation. The online version isn’t quite ready yet (should be in the next few weeks), but you are welcome to request a preprint from me now. If you attended (the surprisingly excellent) TERN symposium in Canberra last month, you might have seen me give a brief synopsis of our results.

The paper is a rather  in-depth review of how we, 30 fire, animal, plant, soil, landscape, agricultural and freshwater biologists, believe Australia’s new carbon-influenced economy (i.e., carbon price) will impact the country’s biodiversity. Read the rest of this entry »





Crying ‘wolf’ overlooks the foxes: challenging ‘planetary tipping points’

28 02 2013

tipping pointToday, a paper by my colleague, Barry Brook, appeared online in Trends in Ecology and Evolution. It’s bound to turn a few heads.

Let’s not get distracted by the title of the post, or the potential for a false controversy. It’s important to be clear that the planet is indeed ill, and it’s largely due to us. Species are going extinct faster than the would have otherwise. The planet’s climate system is being severely disrupted, so is the carbon cycle. Ecosystem services are on the decline.

But – and it’s a big ‘but’ – we have to be wary of claiming the end of the world as we know it or people will shut down and continue blindly with their growth and consumption obsession. We as scientists also have to be extremely careful not to pull concepts and numbers out of our bums without empirical support.

Specifically, I’m referring to the latest ‘craze’ in environmental science writing – the idea of ‘planetary tipping points‘ and the related ‘planetary boundaries‘. It’s really the stuff of Hollywood disaster blockbusters – the world suddenly shifts into a new ‘state’ where some major aspect of how the world functions does an immediate about-face. Read the rest of this entry »





You’re not even remotely concerned enough

31 08 2012

I’ve just returned from a 6-week trip to the United States and I am now dealing with the intensity of things left undone for so long [sigh]. But that trip was interesting for many reasons. First, and as I’ve already posted, I finished a book with Paul Ehrlich that will be out sometime early in 2013 (but I won’t deal with that here). I also attended an interesting, if slightly confusing, conference on ecosystem services. And finally, I had the pleasure of meeting Tony Barnosky in person, and we decided that we should definitely collaborate on a few things.

Another thing that struck me – and this happens no matter how often I visit the U.S., is just how completely insane that country’s politics are. The extremist, libertarian, plutotheocratic bullshit spewed by the far right to the detriment of the very people who support them is enough to make you vomit. And this startling and thoroughly backward world-view is now starting to penetrate more and more into Australian society and politics. From an environmental perspective, it’s a continuation of a downhill slide that started with Reagan’s destruction of environmentalism in the U.S., and Joh Bjelke-Petersen‘s war on the environment in Australia, and will only continue to get worse.

Of course, the main victim of reason in all these polemic politics is that we are doing next to nothing to mitigate horrendous climate disruption. Only yesterday, George Monbiot was lamenting (nay, pleading) that our governments are doing practically nil to avoid what can only be described as the greatest threat to our way of life since the World War II – in fact, the War and its associated holocaust is small bikkies compared to what awaits us.

And this is the most stressing part – even people who choose to use their brains and accept that we have an immense, global problem on our hands generally are not even remotely concerned enough. Read the rest of this entry »





Evolution here and now

17 02 2011

Here’s a guest post from one of my PhD students, Salvador Herrando-Peréz. Salva is working on theoretical aspects of density feedback mechanisms among different species, and is especially eclectic with his interests in biology. Salva regularly contributes to lay natural history magazines, especially in his native tongue Castellano (Spanish), and he is an active member of the Spanish organisation Bioestudios Saganta, a non-profit national organisation fully devoted to scientific research and its popularisation with a focus on biodiversity conservation.

I’ve asked my students to start contributing to ConservationBytes.com, and Salva is leading the charge.

Evolution evokes ideas such as fossils, geological eras and time scales of hundreds of thousands to millions of years. Only recently have we started to appreciate that such ‘macro-evolution’ is the result of accumulated changes in the morphology and genes of species from one generation to the next: days for HIV strands, months for a planktonic rotifer, or years for a poplar.

The Britons Peter and Rose Mary Grant published in 2002 a 30-year study on Darwin’s finches from Daphne Major (Galapagos, Ecuador) – a popular study organism since Charles Darwin’s Origin of species (Grant & Grant 2002). In such a short period of time, covering only six generations of these granivorous birds, several extreme droughts altered the type and abundance of seeds, and potentially triggered the evolution of body size, and beak shape and size, up to three times (Figure 1). The two biologists from Princeton reveal that:

  1. evolution is reversible – generations of finches experiencing overall increase in body and beak sizes can lead to future generations with smaller sizes (of course within limits; a finch will never develop the beak of a stork or a hummingbird), and
  2. phenological shifts across generations are unpredictable in so far as they respond to random climatic fluctuations – should droughts of contrasting intensity have occurred in different years over the study period, beaks and bodies might have evolved in other particular fashions. Read the rest of this entry »







Follow

Get every new post delivered to your Inbox.

Join 6,488 other followers

%d bloggers like this: