Disadvantages of marine protected areas

29 02 2016




Stop wasting time

Stop wasting time


24 02 2016

frogWhile I’ve blogged about this before in general terms (here and here), I thought it wise to reproduce the (open-access) chapter of the same name published in late 2013 in the unfortunately rather obscure book The Curious Country produced by the Office of the Chief Scientist of Australia. I think it deserves a little more limelight.

As I stepped off the helicopter’s pontoon and into the swamp’s chest-deep, tepid and opaque water, I experienced for the first time what it must feel like to be some other life form’s dinner. As the helicopter flittered away, the last vestiges of that protective blanket of human technological innovation flew away with it.

Two other similarly susceptible, hairless, clawless and fangless Homo sapiens and I were now in the middle of one of the Northern Territory’s largest swamps at the height of the crocodile-nesting season. We were there to collect crocodile eggs for a local crocodile farm that, ironically, has assisted the amazing recovery of the species since its near-extinction in the 1960s. Removing the commercial incentive to hunt wild crocodiles by flooding the international market with scar-free, farmed skins gave the dwindling population a chance to recover.

redwoodConservation scientists like me rejoice at these rare recoveries, while many of our fellow humans ponder why we want to encourage the proliferation of animals that can easily kill and eat us. The problem is, once people put a value on a species, it is usually consigned to one of two states. It either flourishes as do domestic crops, dogs, cats and livestock, or dwindles towards or to extinction. Consider bison, passenger pigeons, crocodiles and caviar sturgeon.

As a conservation scientist, it’s my job not only to document these declines, but to find ways to prevent them. Through careful measurement and experiments, we provide evidence to support smart policy decisions on land and in the sea. We advise on the best way to protect species in reserves, inform hunters and fishers on how to avoid over-harvesting, and demonstrate the ways in which humans benefit from maintaining healthy ecosystems. Read the rest of this entry »

How to rank journals

18 02 2016

ranking… properly, or at least ‘better’.

In the past I have provided ranked lists of journals in conservation ecology according to their ISI® Impact Factor (see lists for 2008, 2009, 2010, 2011, 2012 & 2013). These lists have proven to be exceedingly popular.

Why are journal metrics and the rankings they imply so in-demand? Despite many people loathing the entire concept of citation-based journal metrics, we scientists, our administrators, granting agencies, award committees and promotion panellists use them with such merciless frequency that our academic fates are intimately bound to the ‘quality’ of the journals in which we publish.

Human beings love to rank themselves and others, the things they make, and the institutions to which they belong, so it’s a natural expectation that scientific journals are ranked as well.

I’m certainly not the first to suggest that journal quality cannot be fully captured by some formulation of the number of citations its papers receive; ‘quality’ is an elusive characteristic that includes inter alia things like speed of publication, fairness of the review process, prevalence of gate-keeping, reputation of the editors, writing style, within-discipline reputation, longevity, cost, specialisation, open-access options and even its ‘look’.

It would be impossible to include all of these aspects into a single ‘quality’ metric, although one could conceivably rank journals according to one or several of those features. ‘Reputation’ is perhaps the most quantitative characteristic when measured as citations, so we academics have chosen the lowest-hanging fruit and built our quality-ranking universe around them, for better or worse.

I was never really satisfied with metrics like black-box Impact Factors, so when I started discovering other ways to express the citation performance of the journals to which I regularly submit papers, I became a little more interested in the field of bibliometrics.

In 2014 I wrote a post about what I thought was a fairer way to judge peer-reviewed journal ‘quality’ than the default option of relying solely on ISI® Impact Factors. I was particularly interested in why the new kid on the block — Google Scholar Metrics — gave at times rather wildly different ranks of the journals in which I was interested.

So I came up with a simple mean ranking method to get some idea of the relative citation-based ‘quality’ of these journals.

It was a bit of a laugh, really, but my long-time collaborator, Barry Brook, suggested that I formalise the approach and include a wider array of citation-based metrics in the mean ranks.

Because Barry’s ideas are usually rather good, I followed his advice and together we constructed a more comprehensive, although still decidedly simple, approach to estimate the relative ranks of journals from any selection one would care to cobble together. In this case, however, we also included a rank-placement resampler to estimate the uncertainty associated with each rank.

I’m pleased to announce that the final version1 is now published in PLoS One2. Read the rest of this entry »

Bad science

10 02 2016

Head in HandsIn addition to the surpassing coolness of reconstructing long-gone ecosystems, my new-found enthusiasm for palaeo-ecology has another advantage — most of the species under investigation are already extinct.

That might not sound like an ‘advantage’, but let’s face it, modern conservation ecology can be bloody depressing, so much so that one sometimes wonders if it’s worth it. It is, of course, but there’s something marvellously relieving about studying extinct systems for the simple reason that there are no political repercussions. No self-serving, plutotheocratic politician can bugger up these systems any more. That’s a refreshing change from the doom and gloom of modern environmental science!

But it’s not all sweetness and light, of course; there are still people involved, and people sometimes make bad decisions in an attempt to modify the facts to suit their creed. The problem is when these people are the actual scientists involved in the generation of the ‘facts’.

As I alluded to a few weeks ago with the publication of our paper in Nature Communications describing the lack of evidence for a climate effect on the continental-scale extinctions of Australia’s megafauna, we have a follow-up paper that has just been published online in Proceedings of the Royal Society B — What caused extinction of the Pleistocene megafauna of Sahul? led by Chris Johnson of the University of Tasmania.

After our paper published earlier this month, this title might seem a bit rhetorical, so I want to highlight some of the reasons why we wrote the review. Read the rest of this entry »

It’s not always best to be the big fish

3 02 2016

obrien_fish_2Loosely following the theme of last week’s post, it’s now fairly well established that humans tend to pick on the big species first.

From fewer big trees, declines of big carnivores, elephant & rhino poaching, to fishing down the web, big species tend to cop it hardest when it comes to human-caused ecological disturbance.

While there are a lot of different combinations of traits that make some species more vulnerable to extinction than others (see examples for legumes, amphibians, sharks & teleosts, and mammals), one of the main ones is species size.

Generally speaking, larger species tend to produce fewer offspring and breed later in life than smaller species. This means that despite larger species tending to live longer than their smaller counterparts, their ‘slow’ reproductive output means that they are generally more susceptible to rapid environmental change (mainly via human intervention). In other words, their capacity for self-replacement is often too low to counteract the offtake from direct exploitation or habitat loss.

Despite a reasonable scientific understanding of this extinction-risk principle, the degree to which human disturbance affects species’ distributions is much less well quantified, and this is especially true for marine species.

I’m proud to announce another fascinating paper led by my postdoc, Camille Mellin, that has just come out online in Nature CommunicationsHumans and seasonal climate variability threaten large-bodied coral reef fish with small ranges.

With the world’s largest combined dataset of coral reef fish surveys for the entire Indo-Pacific (including the coral reef fish biodiversity hotspot — the Coral Triangle), we examined which conditions best described the distribution of fishes over a range of body sizes. Read the rest of this entry »