Faraway fettered fish fluctuate frequently

27 06 2010

Hello! I am Little Fish

Swimming in the Sea.

I have lots of fishy friends.

Come along with me.

(apologies to Lucy Cousins and Walker Books)

I have to thank my 3-year old daughter and one of her favourite books for that intro. Now to the serious stuff.

I am very proud to announce a new Report in Ecology we’ve just had published online early about a new way of looking at the stability of coral reef fish populations. Driven by one of the hottest young up-and-coming researchers in coral reef ecology, Dr. Camille Mellin (employed through the CERF Marine Biodiversity Hub and co-supervised by me at the University of Adelaide and Julian Caley and Mark Meekan of the Australian Institute of Marine Science), this paper adds a new tool in the design of marine protected areas.

Entitled Reef size and isolation determine the temporal stability of coral reef fish populations, the paper applies a well-known, but little-used mathematical relationship between the logarithms of population abundance and its variance (spatial or temporal) – Taylor’s power law.

Taylor’s power law is pretty straightforward itself – as you raise the abundance of a population by 1 unit on the logarithmic scale, you can expect its associated variance (think variance over time in a fluctuating population to make it easier) to rise by 2 logarithmic units (thus, the slope = 2). Why does this happen? Because a log-log (power) relationship between a vector and its square (remember: variance = standard deviation2) will give a multiplier of 2 (i.e., if xy2, then log10x ~ 2log10y).

Well, thanks for the maths lesson, but what’s the application? It turns out that deviations from the mathematical expectation of a power-law slope = 2 reveal some very interesting ecological dynamics. Famously, Kilpatrick & Ives published a Letter in Nature in 2003 (Species interactions can explain Taylor’s power law for ecological time series) trying to explain why so many real populations have Taylor’s power law slopes < 2. As it turns out, the amount of competition occurring between species reduces the expected fluctuations for a given population size because of a kind of suppression by predators and competitors. Cool.

But that application was more a community-based examination and still largely theoretical. We decided to turn the power law a little on its ear and apply it to a different question – conservation biogeography. Read the rest of this entry »





A world of hurt – the webinar

19 05 2010

Ah – finally. The World of Hurt webinar (many thanks to @fang for showing me how to do this).

CJA Bradshaw





A world of hurt – the video

19 05 2010

In case you couldn’t be there in person, here’s the podcast of last week’s talk I gave at the University of Adelaide’s Research Tuesdays seminar series – A world of hurt. The true global death count of environmental degradation.

View video here. See also the ‘Between the Buttons’ preamble AudioBoo here.

CJA Bradshaw

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PhD scholarships in marine plant ecology and conservation

12 05 2010

Two new APAI (Australian Postgraduate Award – Industry) PhD scholarships are available at the University of Adelaide, both in marine ecology and conservation.

Molecular Systematics and Ecology of Marine Macroalgae

Dr. Frederico Gurgel at the University of Adelaide is seeking 2 PhD students interested in working on several aspects of the marine green macroalgal genus Caulerpa. Honour students are also welcome to apply. APAI PhD scholarships are the best-paid scholarships from the Australian Research Council (fees + AU$26,000 p.a. for 3 yrs). Possible co-advisors: Prof. Corey Bradshaw (University of Adelaide/South Australian Research and Development Institute – SARDI), Dr. Jason Tanner (SARDI), and Dr. Marty Deveney (SARDI). External collaborators: Dr. Peter Grewe (CSIRO Marine), Dr. John Runcie (University of Sydney). Starting date: any time.

Integrative approach to the study of Caulerpa taxifolia in Australia: Ecological, Physiology, Phylogeography and DNA barcoding

The students will perform comparative ecological and physiological assays among Australian native and invasive strains of C. taxifolia (and related species) to study their response (e.g., growth, reproduction, photosynthesis, gene expression) to distinct abiotic factors and global climate change scenarios (e.g., pCO2, pH, temperature, light, salinity, nutrients). Students will perform a multi-marker comparative phylogeographic study among 14 invasive (NSW and SA) and 4 native (QLD, NT, WA) populations to determine the origin of introduced populations in temperate Australia. Students will build a dual-marker DNA barcode database of all species of Caulerpa in Australia as a tool to identify morphologically compromised specimens. Additionally, they will perform a molecular-assisted evolutionary (phylogenetic) study of the genus and develop demographic models to predict the fate of Caulerpa populations under different abiotic scenarios. The students will have the option to choose the components of the project they desire.

Desirable skills: 4WD and manual driving, snorkelling, SCUBA diving certification (open water minimum), molecular biology experience.

For more information please contact Dr. Fred Gurgel (e-mail or telephone: +61 8 8222 9291).

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A world of hurt

11 05 2010

Just a quick link to an AudioBoo sound bite preamble about my University of Adelaide‘s Research Tuesdays talk tonight on the human health implications of environmental degradation. Follows on nicely from last week’s ‘environmental reprobates‘ post. Full podcast of talk to come shortly.

Many thanks to Allan and Ian of ‘Between the Buttons‘.

CJA Bradshaw





Who are the world’s biggest environmental reprobates?

5 05 2010

Everyone is a at least a little competitive, and when it comes to international relations, there could be no higher incentive for trying to do better than your neighbours than a bit of nationalism (just think of the Olympics).

We rank the world’s countries for pretty much everything, relative wealth, health, governance quality and even happiness. There are also many, many different types of ‘environmental’ indices ranking countries. Some attempt to get at that nebulous concept of ‘sustainability’, some incorporate human health indices, and other are just plain black box (see Böhringer et al. 2007 for a review).

With that in mind, we have just published a robust (i.e., to missing data, choices for thresholds, etc.), readily quantifiable (data available for most countries) and objective (no arbitrary weighting systems) index of a country’s relative environmental impact that focuses ONLY on environment (i.e., not human health or economic indicators) – something no other metric does. We also looked at indices relative to opportunity – that is, looking at how much each country has degraded relative to what it had to start with.

We used the following metrics to create a combined environmental impact rank: natural forest loss, habitat conversion, fisheries and other marine captures, fertiliser use, water pollution, carbon emissions from land-use change and threatened species.

The paper, entitled Evaluating the relative environmental impact of countries was just published in the open-access journal PLoS One with my colleagues Navjot Sodhi of the National University of Singapore (NUS) and Xingli Giam, formerly of NUS but now at Princeton University in the USA.

So who were the worst? Relative to resource availability (i.e,. how much forest area, coastline, water, arable land, species, etc. each country has), the proportional environmental impact ranked (from worst) the following ten countries:

  1. Singapore
  2. Korea
  3. Qatar
  4. Kuwait
  5. Japan
  6. Thailand
  7. Bahrain
  8. Malaysia
  9. Philippines
  10. Netherlands

When considering just the absolute impact (i.e., not controlling for resource availability), the worst ten were:

  1. Brazil
  2. USA
  3. China
  4. Indonesia
  5. Japan
  6. Mexico
  7. India
  8. Russia
  9. Australia
  10. Peru

Interestingly (and quite unexpectedly), the authors’ home countries (Singapore, Australia, USA) were in either the worst ten proportional or absolute ranks. Embarrassing, really (for a full list of all countries, see supporting information). Read the rest of this entry »





A world of hurt

21 04 2010

Given it’s only a little under 3 weeks away, I thought I’d advertise an upcoming free public lecture I’m giving for the University of Adelaide‘s highly popular Research Tuesdays programme.

The Research Tuesdays team have done a fantastic job of putting together the associated promotional material, so I’m more or less going to reproduce it here.

The topic is about the global-scale evidence for declining human health from environmental degradation – it’s new research that I haven’t yet published, and so it’ll be exciting to start disseminating the amazing results my colleagues and I have found in a public forum.

So join us on 11 May at the University of Adelaide for what I promise will be an interesting (if not frightening) public lecture. Details below. Read the rest of this entry »





Conservation jobs at the University of Adelaide

13 04 2010

I’m posting the advertisements for two new conservation jobs in the Global Ecology Group at the University of Adelaide.

This Australian Research Council-funded Discovery Project seeks to determine whether functional forms of spatially explicit population dynamics are generalisable across taxa with similar attributes and range limiting factors. By considering the effects of multiple interacting factors (biotic and abiotic) on the demographic determinants of species’ habitat suitability and geographic distributional limits, the research will provide a foundation on which to develop adaptive conservation strategies in response to the anticipated impacts of global change; examine the complexities and potentially irreducible uncertainties in forecasting and managing biodiversity; and identify limitations associated with different modelling approaches. Read the rest of this entry »





China’s insatiable lust for tropical timber

4 04 2010

If you’ve been following ConservationBytes.com for the past few weeks, you’ll know that William Laurance was in town and gave a fantastic set of talks (download podcasts here). As a parting gift, he put together a brief post on one huge aspect of the tropical deforestation crisis we know face. Thanks, Bill.

© AAAS

I greatly enjoyed my recent visit to the University of Adelaide, and especially want to thank my host, Corey Bradshaw, for showing me a wonderful time there.

Corey asked me to contribute a brief blog for ConservationBytes.com and so I thought I’d highlight a paper in Science last week by my old friend Jianguo “Jack” Liu at Michigan State University. In his paper China’s road to sustainability, Jack describes the battle to improve environmental sustainability in China–a battle that is not progressing very well, all factors considered.

China’s explosive economic growth and environmental deterioration is also affecting other countries, especially those with timber, minerals or other resources that China wants. Today, more than half of the timber shipped anywhere in the world is destined for China–some 45 million m3 per year, an incredible total. Read the rest of this entry »





How to restore a tropical rain forest

6 11 2009

thiakiHere’s a little story for you about how a casual chat over a glass of wine (or many) can lead to great scientific endeavours.

A few years ago I was sitting in the living room of my good friends Noel Preece and Penny van Oosterzee in Darwin chatting about life, the universe, and everything. They rather casually mentioned that they would be selling their environmental consulting company and their house and moving to the Queensland rain forest. Ok – sounded like a pretty hippy thing to do when you’re thinking about ‘retiring’ (only from the normal grindstone, at least). But it wasn’t about the easy life away from it all (ok, partially, perhaps) – they wanted to do something with their reasonably large (181 ha), partially deforested (51-ha paddock) property investment. By ‘something’, I mean science.

So they asked me – how would we go about getting money to investigate the best way to reforest a tropical rain forest? I had no idea. As it turns out, no one really knows how to restore rain forests properly. Sure, planting trees happens a lot, but the random, willy-nilly, unquantified ways in which it is done means that no one can tell you what the biggest biodiversity bang for your buck is, or even if it can compete on the carbon sequestration front.

Why carbon sequestration? Well, in case you’ve had your head up your bum for the last decade, one of the major carbon mitigating schemes going is the offset idea – for every tonne of carbon you emit as a consumer, you (or more commonly, someone else you pay) plant a certain number of trees (because trees need carbon to grow and so suck it out of the atmosphere). Nice idea, but if you deforest native ecosystems just to bash up quick-growing monoculture plantations of (usually) exotic species with little benefit to native biota, biodiversity continues to spiral down the extinction vortex. So, there has to be a happy medium, and there has to be a way to measure it.

So I said to Penny and Noel “Why don’t we bash together a proposal and get some experts in the field involved and submit it to the Australian Research Council (ARC) for funding?” They thought that was a smashing idea, and so we did.

Fast forward a few years and … success! The Thiaki Project was born (‘Thiaki’ is the name of the Creek flowing through the property north of Atherton – seems to be of Greek origin). We were extremely lucky to find a new recruit to the University of Queensland, Dr. Margie Mayfield (who worked previously with Paul Ehrlich), who was not only an expert in the area of tropical reforestation for biodiversity, she also had the time and energy to lead the project. We garnered several other academic and industry partners and came up with a pretty sexy experiment that is just now getting underway thanks to good old Mr. ARC.

The project is fairly ambitious, even though the experiments per se are fairly straight forward. We’re using a randomised block design where we are testing 3 tree diversity treatments (monoculture, 1 species each from 6 families, and 5 species each from those same 6 families) and two planting densities (high and low). The major objective is to see what combination of planting density and native tree species provides the most habitat for the most species. We’re starting small, looking mainly at various insects as they start to use the newly planted blocks, but might expand the assessments (before planting and after) to reptiles, amphibians and possibly birds later on.

But we’re not stopping there – we were fortunate enough to get get a clever soil scientist, Dr. David Chittleborough of the University of Adelaide, involved so we could map the change in soil carbon during the experiment. Our major challenge is to find the right combination of tree species and planting techniques that restore native biodiversity the most effectively, all the while maximising carbon sequestration from the growing forest. And of course, we’re trying to do this as most cost-effectively as we can – measuring the relative costs will give landowners contemplating reforestation the scale of expenditures expected.

I’m pretty proud of what Margie, Noel, Penny and the rest of the team have accomplished so far, and what’s planned. Certainly the really exciting results are years away yet, but stay tuned – Thiaki could become the model for tropical reforestation worldwide. Follow the Thiaki Project website for regular updates.

I’d also love to recreate the Thiaki Project in southern Australia because as it turns out, no one knows how to maximise biodiversity and carbon sequestration for the lowest cost in temperate reforestation projects either. All we need is a few hundred hectares of deforested land (shouldn’t be hard to find), about $1 million to start, and a bit of time. Any takers?

CJA Bradshaw

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carbon offset

© C. Madden





Charles Darwin, evolution and climate change denial

5 08 2009

DarwinThis week a mate of mine was conferred her degree at the University of Adelaide and she invited me along to the graduation ceremony. Although academic graduation ceremonies can be a bit long and involve a little too much applause (in my opinion), I was fortunate enough to listen to the excellent and inspiring welcoming speech made by the University of Adelaide’s Dean of Science, Professor Bob Hill.

Professor Hill is a world-renown expert in plant evolution, systematics and ecophysiology, and he gave a wonderful outline of the importance of Darwin’s legacy for today’s burgeoning problem solvers. I am reproducing Prof. Hill’s speech here (with his permission) as a gift to readers of ConservationBytes.com. I hope you enjoy it as much as I did.

Chancellor, Vice Chancellor, distinguished guests, members of staff, friends and family of graduates, and, most importantly of all, the new graduates, I am very pleased to have been asked to speak to you today, because 2009 marks one of the great anniversaries that we will see in our lifetimes. 200 years ago, on February 12th 1809, Charles Robert Darwin was born. To add to the auspicious nature of this year, 150 years ago, John Murray published the first edition of Darwin’s most famous book, titled On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life, better known to us all today as The Origin of Species.

I believe that from a modern perspective, Darwin was the most influential person who has ever lived. Darwin’s impact on how we think and work is much more profound than most people realise. He changed the entire way in which we go about living. Today, I want to talk to you briefly about how Darwin had this impact.

Darwin was a great observer and a great writer, but above all he was a great critical thinker. He became a scientist by a round about route, planning to be a doctor and a minister of religion along the way, although his passion was always natural history. He was not a great undergraduate student, but he benefited enormously from contact he had with University staff outside the formal classroom. His potential must have been obvious, because he was strongly recommended at a relatively young age, to take the position of naturalist and gentleman companion to Captain Robert Fitzroy on his famous five year voyage of the Beagle. Following this voyage, Darwin never physically left Britain again, but intellectually he roamed far and wide. Darwin was one of the great letter writers. He wrote thousands of letters to contacts all over the world, requesting specimens, data and opinions, and he worked relentlessly at analysing what he received back.

Over many years as a practising scientist I have met a lot of people with a passion for natural history, some of them trained scientists like Darwin, some of them gifted amateurs. There is a very obvious distinction between those with and without formal scientific training at a Tertiary level, but it took me a long time to work out what that distinction is. Let me digress slightly before I explain it.

In today’s terminology we talk a lot about graduate attributes. For some graduates, it is reasonably simple to define the kinds of attributes you expect them to have. I prefer engineers whose bridges don’t fall down, lawyers who keep me out of jail unnecessarily, accountants who can add up and doctors who do their best to keep me alive and healthy. However, the key attributes we expect of Science graduates are not so simple to define. You will all have one or more specialities where you have more knowledge than those who did not do the relevant courses, but if you are anything like I was when I was sitting out there waiting to graduate, you probably think you did what you had to do in order to pass your exams and you now think you have forgotten most of what you were taught. I can assure you that you haven’t, but I can also assure you that specific knowledge of a scientific subject is not the most important thing you have been taught here.

So what is that special something that separates out a professional scientist? It is the capacity for critical scientific thinking. You are now ready to work as professionals in many fields, and employers will actively seek to hire you because they know you have been trained here to apply a particular approach to problem solving. That approach is not easily obtained and has been taught to you in the most subtle way over the full breadth of what you have been exposed to during your time here. I suspect most of you don’t even know that you now have this skill, but you do. Darwin had it in the most sublime fashion.

When Darwin published the Origin of Species it was the culmination of decades of data gathering, backed up by meticulous analysis. Darwin never swayed from that rigorous approach, which strongly reflected the training he received as a student.

When you are exposed to a new problem, you will approach the solution in a similar way to Darwin. Let me consider the example of climate change. There is a remarkable parallel between the public reaction to the publication of the Origin of Species and the current public reaction to climate change. Darwin suffered a public backlash from people who were not ready to accept such a radical proposition as evolution by means of natural selection and this was reinforced by a significant number of professional scientists who were willing to speak out against him and his theory. As time went by, professional scientists were gradually won over by the weight of evidence, to the point where mainstream science no longer considers evolution as a theory but as scientific fact.

The reality of climate change and its potential impacts has not had a single champion like Darwin, but it has involved a similar slow accumulation of data and very careful analysis and critical thinking over the implications of what the data tell us. Initially, there were many scientists who spoke against the human-caused impact on climate change, but their number is diminishing. Most significantly, the critical analysis undertaken by thousands of mainstream scientists has gained broad political acceptance, despite the best efforts of special interest lobbyists. I suspect Darwin would be fascinated by the way this debate has developed.

Lobbyists who write stern words about how scientists as a whole are engaged in some conspiracy theory to alarm the general population simply do not understand or choose to ignore how scientists work. The world needs the critical and analytical thinking that scientists bring more than ever before. We live on a wonderful, resilient planet, that will, in the very long run, survive and thrive no matter what we do to it. But we are an extremely vulnerable species, and our survival in a manner we would consider as acceptable, is nowhere near as certain. That is the legacy of my generation to yours. I have faith that your generation will be wiser than mine has been, and I know that good science will lead the charge towards providing that wisdom.

Charles Darwin was the greatest scientist of all, and that is partly because he was a great observer and a great writer. But most of all, Darwin was the consummate critical thinker – he collected masses of data himself and from colleagues all over the world and he fashioned those data into the most relevant and elegant theory of all. I will conclude with a brief and well known passage from the first edition of the Origin of Species, which clearly demonstrates the power of Darwin’s writing:

Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.

I hope that the next Charles Darwin is sitting amongst you today. I know that at the very least I am standing in front of a group of people who have all the attributes necessary to be great contributors to the well-being of society and the planet. Be confident of your training and use your skills well. You have a grand tradition to uphold.

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Interview with… ConservationBytes

16 07 2009

CBlogoA few months ago I was asked to do an online interview about ConservationBytes at The Reef Tank. I previously made mention of the interview (see post), but I think it’s time I reproduce it here.

The effects of pollution, carbon build up in the ocean, extinction, loss of coral reefs, over-fishing, and global warming is increasingly becoming more detrimental to our marine life and marine world.

Fortunately our marine ecosystems have Corey Bradshaw on their side. As a conservation ecologist, Corey studies these ecosystems with a passion, trying to understands the interactions between plants and animals that make up these ecosystems as well as what human activity is doing to them.

He has realised long ago that conservation and awareness is crucial to the survival of these living things and carries on the long tradition of studying and trying to understand these ecosystems at the School of Earth & Environmental Sciences at the University of Adelaide in South Australia.

He also avidly blogs about these pertinent issues at ConservationBytes.com, because he felt a need that these marine conservation issues needed to be heard. And he was more then right.

We were lucky enough to grab some time with Corey Bradshaw and he was kind enough to answer some important marine conservation questions, which are important in our desire: to make the marine world a better place.

What is your background in science and conservation?

I have a rather eclectic background in this area. I originally started my university education in general ecology, with a focus on plant ecology in particular (this was the strength of my undergraduate institution). There was no real emphasis on conservation per se until I started my postgraduate studies, although even then I was more interested in the empirical side of theoretical ecology than on conservation itself. It was more or less a gradual process that as I realised just how much we as a species have changed the planet in our (relatively) short time here, I became more and more dedicated to quantifying the links between species loss and how it affects human well-being.

After completing my MSc, PhD and first postdoctoral fellowship in New Zealand and Australia, I had the good fortune to work alongside a few excellent conservation ecologists specialising in extinction dynamics. This is where my mathematical bent and conservation interests really took off and eventually set the stage for most of my research today.

Your blog is ConservationBytes.com. Why the urge to start a blog on conservation only?

It may seem odd that I resisted blogging for many years because I thought it was a colossal time-waster that would take me away from my main scientific research. However, several things convinced me of its need and utility. First, it’s a wonderful vehicle to engage non-scientists about the research one does – let’s face it, most people don’t read scientific journals. Second, it’s interactive; people can ask questions or comment directly online. Third, it overcomes the strict language and technical rigour of most scientific publications and gets to the heart of the issue (it also allows me to express some opinions and speculations that are otherwise forbidden in scientific writing). Fourth, I realised there was a real lack of understanding about basic conservation science among the populace, so providing a vehicle for conservation science dissemination online appeared to be a good idea – there simply wasn’t anything like it when I started only a year ago. Finally, an effective, policy-changing scientist must advertise his/her research through the popular media to be recognised, so it obviously has career benefits.

Tell me about the conservation topics you cover?

ConservationBytes.com covers pretty much any topic that conforms to at least one of the following criteria:

  • It concerns research (previous, ongoing, planned) that is designed to improve the fate of biodiversity, whether locally, regionally or internationally

  • It concerns policy studies, actions or ideas that will have positive bearing on biodiversity conservation

  • It concerns demonstrations of the role biodiversity plays in providing humans with essential ecosystem services

I even have a section I call ‘Toothless’ that highlights ineffective conservation research or policy. Other areas include: exposés of well-known conservation scientists, a collection of links to conservation science journals, and my personal information (publications, CV, media attention).

What is your take on marine conservation? What does marine conservation include?

Given that I have worked in both marine and terrestrial realms from the tropics to the Antarctic, I really see little distinction in terms of conservation. True, the marine realm probably presents more challenges to conservation in some respects because it’s generally much more difficult and expensive to collect meaningful data, and it’s more difficult to control or mitigate people’s behaviour (especially in international waters), but the ecological patterns are the same (although I admit they may operate over different spatial and temporal scales).

Current ‘hot’ topics in marine conservation include the global degradation and loss of coral reef ecosystems (and what to do about it), terrestrial run-off of pollutants and nutrients affecting marine communities, over-fishing and better fishing management strategies, the design of effective marine protected areas, the socio-economic implications of moving people away from direct exploitation to behaviours and economic activities that promote longer-term biological community stability and resilience, and of course, how climate change (via acidification, hypercapnia, temperature change, storm intensification, seal level rise and modified current structure) might exacerbate the systems that are already stressed by the aforementioned problems.

Have you done any work, research in the area of marine conservation?

Yes, quite a bit. Some salient areas include

  • The grey nurse shark Carcharias taurus was the world’s first shark species to receive legislative protection when the east Australian population was listed under the 1984 New South Wales Fisheries Management Act. It has since been listed as globally Vulnerable by the IUCN in 1996 and the east Australian population was declared Critically Endangered in 2003. Previously, we constructed deterministic, density-independent PVA models for the east Australian population that suggested dire prospects for its long-term persistence without direct and immediate intervention. However, deterministic models might be overly optimistic because they do not incorporate stochastic fluctuations that can drive small populations extinct, whereas failing to account for density feedback can predict overly pessimistic. We recently completed a study demonstrating that the most effective measure to reduce extinction risk was to legislate the mandatory use of offset circle hooks in both recreational and commercial fisheries. The increase in dedicated marine reserves and shift from bather protection nets to drumlines had much lower effectiveness.

  • The global extent of illegal, unreported and unregulated (IUU) fishing is valued from US$10-23.5 billion per year, representing between 11 and 26 million tonnes of fish killed annually beyond legal commercial catches. In northern Australia, IUU fishing has advanced as a ‘protein-mining’ wave starting in the South China Sea in the 1970s and now penetrates consistently into the nation’s Exclusive Economic Zone. We have documented the extent of this wave and the implications for higher-order predators such as sharks, demonstrating that IUU fishing has already depleted large predators in Australian territorial waters. Given the negative relationship between IUU fishing takes and governance quality, we propose that deterring invading fishers will need substantially greater investment in border protection, and international accords to improve governance in neighbouring nations, if the tide of extinction is to be effectively mitigated.

  • Determining the extinction risk of the world’s shark and ray species – some work I’ve done recently with colleagues is to examine the patterns of shark biodiversity globally and determine which groups are most at risk of extinction. Not a surprise, but it turns out that the largest species of shark that reproduce the slowest are the most endangered (including all those bitey ones that frighten people).

  • Finally, I’m doing a lot of work now examining how the structure of coral reefs affects fish biodiversity patterns and long-term resilience. It turns out that basic biogeographic predictors (e.g., reef size and relative isolation from other reefs) really do dictate how temporally stable fish populations remain. And as we know, the more variable a population in time and space, the more likely it will go extinct (on average). The practical implication is that we can identify those coral reefs most likely to maintain their fish communities simply by measuring their size and position.

You’re from Australia, correct? What kind of marine conservation is going on there?

I’m originally from Canada, but I’ve spent most of my adult life in Australia (mostly in Tasmania, the Northern Territory, and now, Adelaide in South Australia). I did my PhD in the deep south of New Zealand (Otago University, Dunedin). In Australia, all the aforementioned ‘hot’ areas of marine conservation are in full swing, with greater and greater emphasis on climate change research. I think this aspect is pre-occupying most serious marine ecologists in Australia these days. For example, the southeast of Australia has already experienced some of the fastest warming in the Southern Hemisphere, with massive regional shifts in many species of fish, invertebrates, macroalgae and plankton.

What’s your take on ocean acidification? Do you think people need to be aware of this issue?

I used to believe ocean acidification was THE principal marine conservation issue facing us today, but now I think it’s just another stressor in a cornucopia of stressors. The main issue here is that we still understand so little of its implications for marine biodiversity. Sure, you lower the pH and up the partial CO2 (pCO2) of seawater, and many organisms don’t do so well (in terms of survival, reproduction and growth). However, it’s considerably more complex than this. pH and pCO2 vary substantially in space and time, and we have yet to quantify these patterns or how they are changing for most of the marine realm. Therefore, it’s difficult to simulate ‘real’ and future conditions in the lab.

Another issue is that temperature is changing must faster and so far exposure experiments indicate that it generally has a much more pronounced effect on marine organisms than acidification per se. However, like many climate change issues, a so-called ‘tipping point’ could be just around the corner that makes many marine communities collapse. It’s a frightening prospect, but one that needs a lot more dedicated research.

Can a person own an aquarium and still be considered a marine conservationist in your opinion?

Of course, provided one is cognisant of several important issues. First, most aquarists rely on the importation of non-native species. Lack of vigilance and carelessness has resulted in a suite of alien species being released into naïve ecosystems, resulting in the extinction or reduction of many native fish and invertebrates. Another issue is the transport cost – think how much carbon you are emitting by flying that tropical clownfish to your local pet shop in Norway. Third, do you know from which populations your displayed fish come? Were they harvested sustainably, or were they the last individuals plucked from a dying reef? A good knowledge of an animal’s origin is essential for the responsible aquarist. In my view one should play it safe. I think having aquaria filled with local species that are easily acquired, don’t cost the Earth to transport and pose no risk to native ecosystems is the most responsible way to go. You can also be a lot more certain of sustainable harvest if you live close by the source.

What is your take on climate change and its effect on marine life? Is being aware and educated on this particular topic and how it affects the marine world make someone a marine conservationist?

Awareness is only the first and most basic step. I’d say most of the world is ‘aware’ to some extent. It’s really the change in human behaviour that’s required before we make any true leaps forward. Some of the issues described above get to the heart of behavioural change. To use an analogy, it’s not enough to recognise that you’re an alcoholic, you have to stop drinking too to prevent the damage.

What can we do to raise awareness of the importance of marine conservation and conservation in general?

My personal take on this, and it applies to ALL biodiversity conservation (i.e., not just marine) is that people won’t take it seriously until they see how its loss affects their lives negatively. For example, let’s say we lose all commercially exploitable fish – not having access to delicious and healthy fish protein will mean people change the way fishing is done; that is, they’ll try to force fishers to fish sustainably and consumers to demand responsibly. The same can be said for more esoteric ecosystem services like carbon sequestration, oxygen production, water purification, pollination, waste detoxification, etc. if, and only if, we understand the economic and health benefits of keeping ecosystems intact. We need more research that makes the biodiversity-human benefit link so that people ultimately get the message. Destroying biodiversity means destroying yourself.

As I said before, awareness is only the first step.





Underwater deforestation

26 05 2009
© C. Connell

© S. Connell

I’ve been meaning to blog on this for a while, but am only now getting around to it.

Now, it’s not bulldozers razing our underwater forests – it’s our own filth. Yes, we do indeed have underwater forests, and they are possibly the most important set of species from a biodiversity perspective in temperate coastal waters around the world. I’m talking about kelp. I’ve posted previously about the importance of kelp and how climate change poses a threat to these habitat-forming species that support a wealth of invertebrates and fish. In fact, kelp forests are analogous to coral reefs in the tropics for their role in supporting other biodiversity.

The paper I’m highlighting for the ConservationBytes.com Potential list is by a colleague of mine at the University of Adelaide, Associate Professor Sean Connell, and his collaborators entitled “Recovering a lost baseline: missing kelp forests from a metropolitan coast“. This paper is interesting, novel and applied for several reasons.

First, it sets out some convincing evidence that the Adelaide coastline has experienced a fairly hefty loss of canopy-forming kelp (mainly species like Ecklonia radiata and Cystophora spp.) since urbanisation (up to 70 % !). Now, this might not seem too surprising – we humans have a horrible track record for damaging, exploiting or maltreating biodiversity – but it’s actually a little unexpected given that Adelaide is one of Australia’s smaller major cities, and certainly a tiny city from a global perspective. There hasn’t been any real kelp harvesting around Adelaide, or coastal overfishing that could lead to trophic cascades causing loss through herbivory. Connell and colleagues pretty much are able to isolate the main culprits: sedimentation and nutrient loading (eutrophication) from urban run-off.

Second, one might expect this to be strange because other places around the world don’t have the same kind of response. The paper points out that in the coastal waters of South Australia, the normal situation is characterised by low nutrient concentrations in the water (what we term ‘oligotrophic’) compared to other places like New South Wales. Thus, when you add even a little bit extra to a system not used to it, these losses of canopy-forming kelp ensue. So understanding the underlying context of an ecosystem will tell you how much it can be stressed before all hell breaks loose.

Finally, the paper makes some very strong arguments for why good marine data are required to make long-term plans for conservation – there simply isn’t enough investment in basic marine research to ensure that we can plan responsibly for the future (see also previous post on this topic).

A great paper that uses a combination of biogeography, time series and chemistry to inform about a major marine conservation problem.

CJA Bradshaw

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Woodland Recovery Initiative

12 03 2009

golden wattle (Acacia pycnantha)I’m recommending you view a video presentation (can be accessed by clicking the link below) by A/Prof. David Paton which demonstrates the urgency of reforesting the region around Adelaide. Glenthorne is a 208-ha property 17 km south of the Adelaide’s central business district owned and operated by the University of Adelaide. A major revegetation project called the Woodland Recovery Initative is being organised to achieve the following:

  • reclaim approximately 100 ha of farmland and reconstruct a suitable habitat that encourages the return of native species
  • establish a world-class research centre
  • employ scientists, technicians, teachers and managers to deliver research, educational, community engagement, monitoring and on-ground works
  • develop educational programs that involve local schools in the environmental works, so that young South Australians are engaged in the project and see it as important to the future of their community

In my view, this is a really exciting opportunity to test experimentally the best ways to restore woodlands to maximise biodiversity retention. Once revegetated, the Glenthorne property will link existing reserves to maximise forested area (and as we know, increasing habitat area is one of most effective ways to prevent extinction). The next step is to apply the knowledge gained from the long-term experimentation at Glenthorne to revegetate the regions surrounding Adelaide that have suffered 200 years of heavy deforestation.

I strongly encourage local support of this initiative – it’s not only biodiversity that will benefit – ecosystem services on which the human residents of the greater Adelaide region depend (including extremely important things such as water retention and carbon sequestration) will also be efficiently enhanced by evidence-based ecological restoration of the region. We could certainly use better natural water retention and more carbon sequestration in addition to the re-establishment of many extirpated native species!

VIEW VIDEO BY CLICKING HERE

CJA Bradshaw