Grim tale of global shark declines

25 06 2015
Please don't eat me

Please don’t eat me

How do you prevent declines of species you cannot even see? This is (and has always been) the dilemma for fisheries because, well, humans don’t live underwater. Even when we strap on a metal tank full of air and a pair of fins, we’re still more or less like wounded astronauts peering through a narrow window of glass at the huge, largely empty, ocean space. It’s little wonder then that we have a fairly crap system of estimating fish abundance, and an even worse track record of managing them sustainably.

But humans love to eat fish – the total world estimate of legal fisheries landings is something in the vicinity of 190 million tonnes in 2013, up from 18 million tonnes in 1950 (according to FAO). We’re probably familiar with some of the losers of that massive harvest, with species like tunas, bill fishes and orange roughy making the news for catastrophic declines in abundance over the last 30-40 years. And we’re not even talking about the estimated tragedy that is illegal, unreported and unregulated (IUU) fishing.

Back in 1999, the FAO started to report that sharks – the new-ish target of many world fisheries resulting from the commercial extinction of many other fin fish fisheries – we’re starting to take the hit. Once generally ignored by fishing industries, sharks soon became popular target species. Then in 2003, Julia Baum and colleagues famously (and somewhat controversially) sounded the alarm for sharks in the Gulf of Mexico by some claims of major and catastrophic declines of large, predatory sharks. While some of the subsequent to-ing and fro-ing in the literature challenged these claims, Baum’s excellent work was ultimately vindicated.

Since then, more and more evidence that sharks are in trouble has surfaced, including the assessment of the reported (again, only legal) catch indicated heavy depletion of coastal sharks even by 1975, and the estimate that 25% of all shark and ray species have an elevated extinction risk, mainly resulting from overfishing. Now even the direct fisheries landings statistics are confirming this grim tale. Read the rest of this entry »





National commitment to conservation brings biodiversity benefits

16 06 2015

united-nations-dayWhat makes some conservation endeavours successful where so many fail to protect biodiversity? Or, how long is a piece of string?

Yes, it’s a difficult question because it’s not just about the biology – such as resilience and area relationships – in fact, it’s probably more about the socio-economic setting that will ultimately dictate how the biodiversity in any particular area fares in response to disturbance.

In the case of protected areas (that I’ll just refer to as ‘reserves’ for the remainder of this post), there’s been a lot of work done about the things that make them ‘work’ (or not) in terms of biodiversity preservation. Yes, we can measure investment, how much the community supports and is involved with the reserve, how much emphasis is put on enforcement, the types of management done within (and outside) of the reserves, et ceteraet cetera. All of these things can (and have to some extent) been correlated with indices of the fate of the biodiversity within reserves, such as rates and patterns of deforestation, the amount of illegal hunting, and the survival probability of particular taxa.

But the problem with these indices is that there are just indices – they probably do not encapsulate the overall ‘health’ of the biodiversity within a reserve (be that trends in the overall abundance of organisms, the resilience of the community as a whole to future disturbances, or the combined phylogenetic diversity of the ecosystem). This is because there are few long-term monitoring programmes of sufficient taxonomic and temporal breadth to summarise these components of complex ecosystems (i.e., ecology is complex). It’s no real surprise, and even though we should put a lot more emphasis on targeted, efficient, long-term biodiversity monitoring inside and outside of all major biodiversity reserves, the cold, hard truth of it is that we’ll never manage to get the required systems in place. Humanity just doesn’t value it enough. Read the rest of this entry »





50/500 or 100/1000 debate not about time frame

26 06 2014

Not enough individualsAs you might recall, Dick Frankham, Barry Brook and I recently wrote a review in Biological Conservation challenging the status quo regarding the famous 50/500 ‘rule’ in conservation management (effective population size [Ne] = 50 to avoid inbreeding depression in the short-term, and Ne = 500 to retain the ability to evolve in perpetuity). Well, it inevitably led to some comments arising in the same journal, but we were only permitted by Biological Conservation to respond to one of them. In our opinion, the other comment was just as problematic, and only further muddied the waters, so it too required a response. In a first for me, we have therefore decided to publish our response on the arXiv pre-print server as well as here on ConservationBytes.com.

50/500 or 100/1000 debate is not about the time frame – Reply to Rosenfeld

cite as: Frankham, R, Bradshaw CJA, Brook BW. 2014. 50/500 or 100/1000 debate is not about the time frame – Reply to Rosenfeld. arXiv: 1406.6424 [q-bio.PE] 25 June 2014.

The Letter from Rosenfeld (2014) in response to Jamieson and Allendorf (2012) and Frankham et al. (2014) and related papers is misleading in places and requires clarification and correction, as follows: Read the rest of this entry »





We’re sorry, but 50/500 is still too few

28 01 2014

too fewSome of you who are familiar with my colleagues’ and my work will know that we have been investigating the minimum viable population size concept for years (see references at the end of this post). Little did I know when I started this line of scientific inquiry that it would end up creating more than a few adversaries.

It might be a philosophical perspective that people adopt when refusing to believe that there is any such thing as a ‘minimum’ number of individuals in a population required to guarantee a high (i.e., almost assured) probability of persistence. I’m not sure. For whatever reason though, there have been some fierce opponents to the concept, or any application of it.

Yet a sizeable chunk of quantitative conservation ecology develops – in various forms – population viability analyses to estimate the probability that a population (or entire species) will go extinct. When the probability is unacceptably high, then various management approaches can be employed (and modelled) to improve the population’s fate. The flip side of such an analysis is, of course, seeing at what population size the probability of extinction becomes negligible.

‘Negligible’ is a subjective term in itself, just like the word ‘very‘ can mean different things to different people. This is why we looked into standardising the criteria for ‘negligible’ for minimum viable population sizes, almost exactly what the near universally accepted IUCN Red List attempts to do with its various (categorical) extinction risk categories.

But most reasonable people are likely to agree that < 1 % chance of going extinct over many generations (40, in the case of our suggestion) is an acceptable target. I’d feel pretty safe personally if my own family’s probability of surviving was > 99 % over the next 40 generations.

Some people, however, baulk at the notion of making generalisations in ecology (funny – I was always under the impression that was exactly what we were supposed to be doing as scientists – finding how things worked in most situations, such that the mechanisms become clearer and clearer – call me a dreamer).

So when we were attacked in several high-profile journals, it came as something of a surprise. The latest lashing came in the form of a Trends in Ecology and Evolution article. We wrote a (necessarily short) response to that article, identifying its inaccuracies and contradictions, but we were unable to expand completely on the inadequacies of that article. However, I’m happy to say that now we have, and we have expanded our commentary on that paper into a broader review. Read the rest of this entry »





Making the scientific workshop work

28 10 2013
I don't mean this

I don’t mean this

I’ve been a little delayed in blogging this month, but for a very good reason – I’ve just experienced one of the best workshops of my career. I’d like to share a little of that perfect science recipe with you now.

I’ve said it before, but it can stand being repeated: done right, workshops can be some of the most efficient structures for doing big science.

First, let me define ‘workshop’ for those of you who might have only a vague notion of what it entails. To me, a workshop is a small group of like-minded scientists – all of whom possess different skills and specialities – who are brought together to achieve one goal. That goal is writing the superlative manuscript for publication.

So I don’t mean just a bog-standard chin-wag infected with motherhoods and diatribes. Workshops are not mini-conferences; neither are they soap boxes. It is my personal view that nothing can waste a scientist’s precious time more than an ill-planned and aimless workshop.

But with a little planning and some key ingredients that I’ll list shortly, you can turn a moderately good idea into something that can potentially shake the foundations of an entire discipline. So what are these secret ingredients? Read the rest of this entry »





Advice for getting your dream job in conservation science

4 12 2012

people management

A few weeks ago I heard from an early-career researcher in the U.S. who had some intelligent things to say about getting jobs in conservation science based on a recent Conservation Biology paper she co-wrote. Of course, for all the PhDs universities are pumping out into the workforce, there will never be enough positions in academia for them all. Thus, many find their way into non-academic positions. But – does a PhD in science prepare you well enough for the non-academic world? Apparently not.

Many post-graduate students don’t start looking at job advertisements until we are actually ready to apply for a job. How often do we gleam the list of required skills and say, “If only I had done something to acquire project management skills or fundraising skills, then I could apply for this position…”? Many of us start post-graduate degrees assuming that our disciplinary training for that higher degree will prepare us appropriately for the job market. In conservation science, however, many non-disciplinary skills (i.e., beyond those needed to be a good scientist) are required to compete successfully for non-academic positions. What are these skills?

Our recent paper in Conservation Biology (Graduate student’s guide to necessary skills for nonacademic conservation careers) sifted through U.S. job advertisements and quantified how often different skills are required across three job sectors: nonprofit, government and private. Our analysis revealed that several non-disciplinary skills are particularly critical for job applicants in conservation science. The top five non-disciplinary skills were project management, interpersonal, written communication, program leadership and networking. Approximately 75% of the average job advertisement focused on disciplinary training and these five skills. In addition, the importance of certain skills differed across the different job sectors.

Below, we outline the paper’s major findings with regard to the top five skills, differences among sectors, and advice for how to achieve appropriate training while still in university. Read the rest of this entry »





Protected areas work, but only when you put in the effort

15 11 2012

Apologies for the delay in getting this latest post out. If you read my last one, you’ll know that I’ve been in the United Kingdom for the last week. I’m writing this entry in the train down from York to Heathrow, from which I’ll shortly begin the gruelling 30-hour trip home to Adelaide.

Eight days on the other side of the planet is a bit of a cyclonic trip, but I can honestly say that it was entirely worth it. My first port of call was London where I attended the Zoological Society of London’s Protected Areas Symposium, which is the main topic on which I’ll elaborate shortly.

But I also visited my friend and colleague, Dr. Kate Parr at the University of Liverpool, where I also had the pleasure of talking with Rob Marrs and Mike Begon. Liverpool was also where I first observed the habits of a peculiar, yet extremely common species – the greater flabby, orange-skinned, mini-skirted, black-eyed scouser. Fascinating.

I then had the privilege and serendipitous indulgence of visiting the beautiful and quaint city of York where I gave another talk to the Environment Department at the University of York. My host, Dr. Kate Arnold was simply lovely, and I got to speak with a host of other very clever people including Callum Roberts, Phil Platts, Andy Marshall and Murray Rudd. Between the chats and real ales, mushy peas, pork pies and visits to the Minster, I was in north English heaven.

Enough of the cultural compliments – the title of this post was the take-home message of the ZSL symposium. There I gave a 25-minute talk summarising our recent paper on the performance of tropical protected areas around the globe, and added a few extra analyses in the process. One interesting result that was missing from the original paper was the country-level characteristics that explain variation in protected area ‘health’ (as we defined it in the Nature paper). After looking at a number of potential drives, including per-capita wealth, governance quality, environmental performance, human population density and the proportion of high conservation-value protected areas (IUCN Ia, Ib, II and IV categories), it came out that at least at that coarse country scale that only the proportion of high conservation-value protected areas explained any additional variation in health. In other words, the more category Ia, Ib, II and IV protected areas a country has (relative to the total), the better their protected areas do on average (and remember, we’re talking largely about developing and tropical nations here). Read the rest of this entry »








Follow

Get every new post delivered to your Inbox.

Join 8,370 other followers

%d bloggers like this: