Value of a good enemy

25 10 2009

alienpredatorI love these sorts of experiments. Ecology (and considering conservation ecology a special subset of the larger discipline) is a messy business, mainly because ecosystems are complex, non-linear, emergent, interactive, stochastic and meta-stable entities that are just plain difficult to manipulate experimentally. Therefore, making inference of complex ecological processes tends to be enhanced when the simplest components are isolated.

Enter the ‘mini-ecosystem-in-a-box’ approach to ecological research. I’ve blogged before about some clever experiments to examine the role of connectivity among populations in mitigating (or failing to mitigate) extinction risk, and alluded to others indicating how harvest reserves work to maximise population persistence. This latest microcosm experiment is another little gem and has huge implications for conservation.

A fairly long-standing controversy in conservation biology, and in invasive species biology in particular, is whether intact ecosystems are in any way more ‘resilient’ to invasion by alien species (the latter most often being deliberately or inadvertently introduced by humans – think of Australia’s appalling feral species problems; e.g., buffalo, foxes and cats, weeds). Many believe by default that more ‘pristine’ (i.e., less disturbed by humans) communities will naturally provide more ecological checks against invasives because there are more competitors, more specialists and more predators. However, considering the ubiquity of invasives around the world, this assumption has been challenged vehemently.

The paper I’m highlighting today uses the microcosm experimental approach to show how native predators, when abundant, can reduce the severity of an invasion. Using a system of two mosquito species (one ‘native’ – what’s ‘native’ in a microcosm? [another subject] – and one ‘invasive’) and a native midge predator, Juliano and colleagues demonstrate in their paper Your worst enemy could be your best friend: predator contributions to invasion resistance and persistence of natives that predators are something you want to keep around.

In short, they found little evidence of direct competition between the two mosquitoes in terms of abundance when placed together without predators, but when the midges were added, the persistence of the invasive mosquito was reduced substantially. Of course, the midge predators did do their share of damage on the native mosquitoes in terms of reducing the latter’s abundance, but through a type of competitive release from their invasive counterparts, the midges’ reduction of the invasive species left the native mosquito free to develop faster (i.e., more per capita resources).

Such a seemingly academic result has huge conservation implications. In most systems, predators are some of the largest and slowest-reproducing species, so they are characteristically the first to feel the hammer of human damage. From bears to sharks, and tigers to wolves, big, charismatic predators are on the wane worldwide. Juliano and colleagues’ nice experimental work with insects reminds us that keeping functioning native ecosystems intact from all trophic perspectives is imperative.

CJA Bradshaw

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ResearchBlogging.orgJuliano, S., Lounibos, L., Nishimura, N., & Greene, K. (2009). Your worst enemy could be your best friend: predator contributions to invasion resistance and persistence of natives Oecologia DOI: 10.1007/s00442-009-1475-x





Sleuthing the Chinese green slime monster

21 10 2009

greenslimemonsterI just returned from a week-long scientific mission in China sponsored by the Australian Academy of Science, the Australian Academy of Technological Sciences and Engineering and the Chinese Academy of Sciences. I was invited to attend a special symposium on Marine and Deltaic Systems where research synergies between Australian and Chinese scientists were to be explored. The respective academies really rolled out the red carpet for the 30 or so Australian scientists on board, so I feel very honoured to have been invited.

During our marine workshop, one of my Chinese counterparts, Dongyan Liu from the Yantai Institute for Coastal Zone Research, presented a brilliant piece of ecological sleuthing that I must share with readers of ConservationBytes.com.

The first time you go to China the thing that strikes you is that everything is big – big population, big cities, big buildings, big projects, big budgets and big, big, big environmental problems. After many years of overt environmental destruction in the name of development, the Chinese government (aided by some very capable scientists) is now starting to address the sins of the past.

Liu and colleagues published their work earlier this year in Marine Pollution Bulletin in a paper entitled World’s largest macroalgal bloom caused by expansion of seaweed aquaculture in China, which describes a bloody massive outbreak of a particularly nasty ‘green tide’.

What’s a ‘green tide’? In late June 2008 in the coastal city of Qingdao not far from Beijing (and just before the 2008 Olympics), a whopping 1 million tonnes of green muck washed up along approximately 400 km2 of coastline. It took 10,000 volunteers 2 weeks to clean up the mess. At the time, many blamed the rising eutrophication of coastal China as the root cause, and a lot of people got their arse kicked over it. However, the reality was that it wasn’t so simple.

The Yellow Sea abutting this part of the Chinese coast is so named because of its relatively high productivity. Warm waters combined with good mixing mean that there are plenty of essential nutrients for green things to grow. So, adding thousands of tonnes of fertilisers from Chinese agricultural run-off seems like a logical explanation for the bloom.

Qingdoa green tide 2008 © Elsevier

Qingdao green tide 2008 © Elsevier

However, it turns out that the bulk of the green slime was comprised of a species called Enteromorpha prolifera, and it just so happens that this particularly unsavoury seaweed loves to grow on the infrastructure used for the aquaculture of nori (a.k.a. amanori or zicai) seaweed (mainly, Porphyra yezoensis). Problem is, P. yezoensis is grown mainly on the coast hundreds of kilometres to the south.

Liu and colleagues examined both satellite imagery and detailed oceanographic data from the period prior to the green tide and not only spotted green splotches many kilometres long, they also determined that the current flow and wind direction placed the trajectory of any green slime mats straight for Qingdao.

So, how does it happen? Biofouling by E. prolifera on P. yezoensis aquaculture frames is dealt with mainly by manual cleaning and then dumping the unwanted muck on the tidal flats. When the tide comes back in, it washes many thousands of kilos of this stuff back out to sea, which then accumulates in rafts and continues to grow in the warm, rich seas. Subsequent genetic work also confirmed that the muck at sea was the same stock as the stuff growing on the aquaculture frames.

Apart from some lovely sleuthing work, the implications are pretty important from a biodiversity perspective. Massive eutrophication coupled with aquaculture that inadvertently spawns a particularly nasty biofouling species is a good recipe for oxygen depletion in areas where the eventual slime monster starts to decay. This can lead to so-called ‘dead’ zones that can kill off huge numbers of marine species. So, the proper management of aquaculture in the hungry Goliath that is China becomes essential to reduce the incidence of dead zones.

Fortunately, it looks like Liu and colleagues’ work is being taken seriously by the Chinese government who is now contemplating financial support for aquaculturists to clean their infrastructure properly without dumping the sludge to sea. A simple policy shift could save a lot of species, a lot of money, and a lot of embarrassment (not to mention prevent a lot of bad smells).

CJA Bradshaw

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ResearchBlogging.orgLiu, D., Keesing, J., Xing, Q., & Shi, P. (2009). World’s largest macroalgal bloom caused by expansion of seaweed aquaculture in China Marine Pollution Bulletin, 58 (6), 888-895 DOI: 10.1016/j.marpolbul.2009.01.013





October Issue of Conservation Letters

18 10 2009

The second-to-last issue in 2009 (October) of Conservation Letters is now out. Click here for full access.

cl2-5

Household goods made of non-timber forest products. © N. Sasaki

Papers in this issue:





Life and death on Earth: the Cronus hypothesis

13 10 2009
Cronus

Cronus

Bit of a strange one for you today, but here’s a post I hope you’ll enjoy.

My colleague, Barry Brook, and I recently published a paper in the very new and perhaps controversial online journal , the Journal of Cosmology. Cosmology? According to the journal, ‘cosmology’ is:

“the study and understanding of existence in its totality, encompassing the infinite and eternal, and the origins and evolution of the cosmos, galaxies, stars, planets, earth, life, woman and man”.

The journal publishes papers dealing with ‘cosmology’ and is a vehicle for those who wish to publish on subjects devoted to the study of existence in its totality.

Ok. Quite an aim.

Our paper is part of the November (second ever) issue of the journal entitled Asteroids, Meteors, Comets, Climate and Mass Extinctions, and because we were the first to submit, we managed to secure the first paper in the issue.

Our paper, entitled The Cronus hypothesis – extinction as a necessary and dynamic balance to evolutionary diversification, introduces a new idea in the quest to find that perfect analogy for understanding the mechanisms dictating how life on our planet has waxed and waned over the billions of years since it first appeared.

Gaia

Gaia

In the 1960s, James Lovelock conceived the novel idea of Gaia – that the Earth functions like a single, self-regulating organism where life itself interacts with the physical environment to maintain conditions favourable for life (Gaia was the ancient Greeks’ Earth mother goddess). Embraced, contested, denounced and recently re-invigorated, the idea has evolved substantially since it first appeared. More recently (this year, in fact), Peter Ward countered the Gaia hypothesis with his own Greek metaphor – the Medea hypothesis. Essentially this view holds that life instead ‘seeks’ to destroy itself in an anti-Gaia manner (Medea was the siblicidal wife of Jason of the Argonauts). Ward described his Medea hypothesis as “Gaia’s evil twin”.

One can marvel at the incredible diversity of life on Earth (e.g., conservatively, > 4 million protists, 16600 protozoa, 75000-300000 helminth parasites, 1.5 million fungi, 320000 plants, 4-6 million arthropods, > 6500 amphibians, 10000 birds and > 5000 mammals) and wonder that there might be something in the ‘life makes it easier for life’ idea underlying Gaia. However, when one considers that over 99 % of all species that have ever existed are today extinct, then a Medea perspective might dominate.

Medea

Medea

Enter Cronus. Here we posit a new way of looking at the tumultuous history of life and death on Earth that effectively relegates Gaia and Medea to opposite ends of a spectrum. Cronus (patricidal son of Gaia overthrown by his own son, Zeus, and banished to Hades) treats speciation and extinction as birth and death in a ‘metapopulation’ of species assemblages split into biogeographic realms. Catastrophic extinction events can be brought about via species engineering their surroundings by passively modifying the delicate balance of oxygen, carbon dioxide and methane – indeed, humans might be the next species to fall victim to our own Medean tendencies. But extinction opens up new niches that eventually elicit speciation, and under conditions of relative environmental stability, specialists evolve because they are (at least temporarily) competitive under those conditions. When conditions change again, extinction ensues because not all can adapt quickly enough. Just as all individuals born in a population must eventually die, extinction is a necessary termination.

We think the Cronus metaphor has a lot of advantages over Gaia and Medea. The notion of a community of species as a population of selfish individuals retains the Darwinian view of contestation; self-regulation in Cronus occurs naturally as a result of extinction modifying the course of future evolution. Cronus also makes existing mathematical tools developed for metapopulation theory amenable to broader lines of inquiry.

For example, species as individuals with particular ‘mortality’ (extinction) rates, and lineages with particular ‘birth’ (speciation) rates, could interact and disperse among ‘habitats’ (biogeographical realms). ‘Density’ feedback could be represented as competitive exclusion or symbioses. As species dwindle, feedbacks such as reduced community resilience that further exacerbate extinction risk (Medea-like phase), and stochastic fluctuation around a ‘carrying capacity’ (niche saturation) arising when environmental conditions are relatively stable is the Gaia-like phase. Our Cronus framework is also scale-invariant – it could be applied to microbial diversity on another organism right up to inter-planetary exchange of life (panspermia).

What’s the relevance to conservation? We’re struggling to prevent extinction, so understanding how it works is an essential first step. Without the realisation that extinction is necessary (albeit, at rates preferably slower than they are currently), we cannot properly implement conservation triage, i.e., where do we invest in conservation and why?

We had fun with this, and I hope you enjoy it too.

CJA Bradshaw

ResearchBlogging.orgBradshaw, C.J.A., & Brook, B.W. (2009). The Cronus Hypothesis – extinction as a necessary and dynamic balance to evolutionary diversification Journal of Cosmology, 2, 201-209 Other: http://journalofcosmology.com/Extinction100.html

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Managing for extinction

9 10 2009

ladderAh, it doesn’t go away, does it? Or at least, we won’t let it.

That concept of ‘how many is enough?’ in conservation biology, the so-called ‘minimum viable population size‘, is enough to drive some conservation practitioners batty.

How many times have we heard the (para-) phrase: “It’s simply impractical to bring populations of critically endangered species up into the thousands”?

Well, my friends, if you’re not talking thousands, you’re wasting everyone’s time and money. You are essentially managing for extinction.

Our new paper out online in Biological Conservation entitled Pragmatic population viability targets in a rapidly changing world (Traill et al.) shows that populations of endangered species are unlikely to persist in the face of global climate change and habitat loss unless they number around 5000 mature individuals or more.

After several meta-analytic, time series-based and genetic estimates of the magic minimum number all agreeing, we can be fairly certain now that if a population is much less than several thousands (median = 5000), its likelihood of persisting in the long run in the face of normal random variation is pretty small.

We conclude essentially that many conservation biologists routinely underestimate or ignore the number of animals or plants required to prevent extinction. In fact, aims to maintain tens or hundreds of individuals, when thousands are actually needed, are simply wasting precious and finite conservation resources. Thus, if it is deemed unrealistic to attain such numbers, we essentially advise that in most cases conservation triage should be invoked and the species in question be abandoned for better prospects

A long-standing idea in species restoration programs is the so-called ‘50/500’ rule; this states that at least 50 adults are required to avoid the damaging effects of inbreeding, and 500 to avoid extinctions due to the inability to evolve to cope with environmental change. Our research suggests that the 50/500 rule is at least an order of magnitude too small to stave off extinction.

This does not necessarily imply that populations smaller than 5000 are doomed. But it does highlight the challenge that small populations face in adapting to a rapidly changing world.

We are battling to prevent a mass extinction event in the face of a growing human population and its associated impact on the planet, but the bar needs to be a lot higher. However, we shouldn’t necessarily give up on critically endangered species numbering a few hundred of individuals in the wild. Acceptance that more needs to be done if we are to stop ‘managing for extinction’ should force decision makers to be more explicit about what they are aiming for, and what they are willing to trade off, when allocating conservation funds.

CJA Bradshaw

(with thanks to Lochran Traill, Barry Brook and Dick Frankham)

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Traill, L.W., Brook, B.W., Frankham, R.R., & Bradshaw, C.J.A. (2009). Pragmatic population viability targets in a rapidly changing world Biological Conservation DOI: 10.1016/j.biocon.2009.09.001





Connectivity paradigm in extinction biology

6 10 2009

networkI’m going to do a double review here of two papers currently online in Proceedings of the Royal Society B: Biological Sciences. I’m lumping them together because they both more or less challenge the pervasive conservation/restoration paradigm that connectivity is the key to reducing extinction risk. It’s just interesting (and slightly amusing) that the two were published in the same journal and at about the same time, but by two different groups.

From our own work looking at the correlates of extinction risk (measured mainly by proxy as threat risk), the range of a population (i.e., the amount of area and number of habitats it covers) is the principal determinant of risk – the smaller your range, the greater your chance of shuffling off this mortal coil (see also here). This is, of course, because a large range usually means that you have some phenotypic plasticity in your habitat requirements, you can probably disperse well, and your not going to succumb to localised ‘catastrophes’ as often. It also probably means (but not always) that your population size increases as your range size increases; as we all know, populations must be beyond their minimum viable population size to have a good chance of persisting random demographic and environmental vagaries.

Well, the two papers in question, ‘Both population size and patch quality affect local extinctions and colonizations‘ by Franzén & Nilssen and ‘Environment, but not migration rate, influences extinction risk in experimental metapopulations‘ by Griffen & Drake, show that connectivity (i.e., the probability that populations are connected via migration) are probably the least important components in the extinction-persistence game.

Using a solitary bee (Andrena hattorfiana) metapopulation in Sweden, Franzén & Nilssen show that population size and food patch quality (measured by number of pollen-producing plants) were directly (but independently) correlated with extinction risk. Bigger populations in stable, high-quality patches persisted more readily. However, connectivity between patches was uncorrelated with risk.

Griffen & Drake took quite a different approach and stacked experimental aquaria full of daphnia (Daphnia magna) on top of one another to influence the amount of light (and hence, amount of food from algal growth) to which the populations had access (it’s interesting to note here that this was unplanned in the experiment – the different algal growth rates related to the changing exposure to light was a serendipitous discovery that allowed them to test the ‘food’ hypothesis!). They also controlled the migration rate between populations by varying the size of holes connecting the aquaria. In short, they found that environmentally influenced (i.e., food-influenced) variation was far more important at dictating population size and fluctuation than migration, showing again that conditions promoting large population size and reducing temporal variability are essential for reducing extinction risk.

So what’s the upshot for conservation? Well, many depressed populations are thought to be recoverable by making existing and fragmented habitat patches more connected via ‘corridors’ of suitable habitat. The research highlighted here suggests that more emphasis should be placed instead on building up existing population sizes and ensuring food availability is relatively constant instead of worrying about how many trickling migrants might be moving back and forth. This essentially means that a few skinny corridors connecting population fragments will probably be insufficient to save our imperilled species.

CJA Bradshaw

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Franzen, M., & Nilsson, S. (2009). Both population size and patch quality affect local extinctions and colonizations Proceedings of the Royal Society B: Biological Sciences DOI: 10.1098/rspb.2009.1584

Griffen, B., & Drake, J. (2009). Environment, but not migration rate, influences extinction risk in experimental metapopulations Proceedings of the Royal Society B: Biological Sciences DOI: 10.1098/rspb.2009.1153





Protecting Australian wilderness

1 10 2009

Today I highlight a new paper just out online in Diversity and Distributions by James Watson and colleagues: Wilderness and future conservation priorities in Australia. It’s certainly one for the Potential list.

KNP

Jim Jim Falls, Kakadu National Park

Australia has a pretty bad biodiversity conservation track record – we have some of the worst mammal extinction trends in the world, and we’ve lost at least 50 % of our forested area since European colonisation. Despite our relatively large system of parks and reserves, things aren’t going to well (even in the parks!).

Our rapidly expanding influence means that we have to start protecting larger and larger areas if we want to have any chance of slowing the modern extinction crisis. This means we have to go beyond dedicated biodiversity reserves and sequester more ‘wilderness’ (defined as “…large areas that have experienced minimal habitat loss“). Watson and colleagues therefore used Australia as a good example to determine the extent to which the national protected area network captures ‘wilderness’, and how Australia’s planned expansion of the reserve system will include ‘wilderness’ in the future.

Although there wasn’t much planning involved initially, Australia (like many other countries) started to take biodiversity conservation seriously in the mid-1990s, such that now we have about 11 % of our 7.7 million km2 land area within a National Reserve System. Planning didn’t feature heavily in the early years, but it has been embraced now by nearly all planning bodies within government.

© Wiley-Blackwell

© Wiley-Blackwell

Using estimates of the total wilderness area in Australia (Fig. a), Watson and colleagues determined how much was included in the Reserve System (Fig. b), and how this value changed between 2000 and 2006.

Of the 2.93 million km2 of wilderness (38 % of land area, mostly in northern and western Australia), only 14 % was protected in 2000. This value increased marginally to 19 % by 2006 as the size of the Reserve System itself increased by 37 % (i.e., from 652597 to 895326 km2).

Bottom line – our growth in reserve area didn’t really capture the necessary wilderness; instead, gains were made in areas largely modified by humans. Even where wilderness has been captured, it’s predominately in ‘multiple use’ regions (incorporating mining, forestry and grazing, for example).

This isn’t a bad thing really – by focussing on areas of high biodiversity value that are under relatively high threat embraces the biodiversity hotspot approach to conservation and emphasises restoration. This is, of course, needed. But not incorporating a wider component of the habitats within wilderness could bias conservation toward range-restricted species.

© Wiley-Blackwell

© Wiley-Blackwell

Watson and colleagues therefore make a number of recommendations:

  1. We should strive to quantify and map spatially the  important ecological and evolutionary processes that drive the distribution and abundance of biodiversity so they can be explicitly incorporated into reserve area prioritisations.
  2. We should focus on predicting the magnitude and distribution of future threats and incorporate them into the spatial prioritisation framework.
  3. We should incorporate realistic constraints (e.g., financial costs) into prioritisation.
  4. We need to map and analyse a range of social and economic factors that define opportunities for conservation in conjunction with information on conservation values, threats and costs.

The bottom line is that we need to find a better balance between planning that protects threatened species and ecosystems in already highly fragmented (threatened) landscapes, and planning that protects large areas of wilderness that still contains most of its conservation values (wilderness). We’re getting there, but slowly, and hopefully in time to save our remaining threatened species from extinction.

CJA Bradshaw

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ResearchBlogging.org

Watson, J., Fuller, R., Watson, A., Mackey, B., Wilson, K., Grantham, H., Turner, M., Klein, C., Carwardine, J., Joseph, L., & Possingham, H. (2009). Wilderness and future conservation priorities in Australia Diversity and Distributions DOI: 10.1111/j.1472-4642.2009.00601.x





Evolution of biodiversity: the hard evidence

25 09 2009

Just a plug for Richard Dawkins’ new book “The Greatest Show on Earth“. Hard to believe, but there are still billions of people who are blind to how life actually works, mainly from the intellectual blindfold of religion.

For more things Dawkins, visit http://richarddawkins.net/.





How to make an effective marine protected area

22 09 2009

Here’s a nice little review from the increasingly impressive Frontiers in Ecology and the Environment which seems to be showcasing a lot of good conservation research lately.

© USGS

© USGS

As we know, the world’s oceans are under huge threat, with predictions of 70 % loss of coral reefs by 2050, decline in kelp forests, loss of seagrasses, over-fishing, pollution and a rapidly warming and acidifying physical environment. Given all these stressors, it is absolutely imperative we spend a good deal of time thinking about the right way to impose restrictions on damage to marine areas – the simplest way to do this is via marine protected areas (MPA).

The science of MPA network design has matured over the last 10-20 years such that there is a decent body of literature now on what we need to do (now the policy makers just have to listen – some  progress there too, but see also here). McLeod and colleagues in the latest issue of Frontiers in Ecology and the Environment have published a review outlining the best, at least for coral reefs, set of recommendations for MPA network design given available information (paper title: Designing marine protected area networks to address the impacts of climate change). Definitely one for the Potential list.

Here’s what they recommend:

Size

  • bigger is always better
  • minimum diameter of an MPA should be 10-20 km to ensure exchange of propagules among protected benthic populations

Shape

  • simple shapes best (squares, rectangles)
  • avoid convoluted shapes to minimise edge effects

Representation

  • protect at least 20-30 % of each habitat

Replication

  • protect at least 3 examples of each marine habitat

Spread

  • select MPA in a variety of temperature regimes to avoid risk of all protected reefs succumbing to future climate changes

Critical Areas

  • protect nursery areas, spawning aggregations, and areas of high species diversity
  • protect areas demonstrating natural resilience or rapid recovery from previous disturbances

Connectivity

  • measure connectivity between MPA to ensure replenishment
  • space maximum distance of 15-20 km apart
  • include whole ecological units
  • buffer core areas
  • protect adjacent areas such as outlying reefs, seagrass beds, mangroves

Ecosystem Function

  • maintain key functional groups of species (e.g., herbivorous fishes)

Ecosystem Management

  • embed MPA in broader management frameworks addressing other threats
  • address and rectify sources of pollution
  • monitor changes

Of course, this is just a quick-and-dirty list as presented here – I highly recommend reading the review for specifics.

CJA Bradshaw

ResearchBlogging.orgMcLeod, E., Salm, R., Green, A., & Almany, J. (2009). Designing marine protected area networks to address the impacts of climate change Frontiers in Ecology and the Environment, 7 (7), 362-370 DOI: 10.1890/070211





What is a species?

18 09 2009

In a bid to save some time given looming grant application deadlines and overdue paper revisions, I’ve opted to reproduce a nice little discussion about how we define ‘species’ in a biodiversity sense. This is a great little synopsis of the species concept by Professor Colin Groves of the Australian National University that aired on ABC Radio National‘s Ockham’s Razor show hosted by Robyn Williams. This is an important discussion because it really dictates how we measure biodiversity, and more importantly, how we should seek to restore it when ‘degraded’. The full transcript can be viewed here, and you can listen here. Below I reproduce the relevant bits of the essay.

butterfliesSpecies, in the words of the great evolutionary biologist George Gaylord Simpson, are lineages evolving separately from others, each with its own unitary evolutionary role and tendencies. They are the units of biodiversity. Everybody uses the term, with greater or lesser degrees of precision, but even biologists, I regret to say, often use it without actually defining what they mean.

It was the great zoologist Ernst Mayr who in 1940 offered the best known definition: ‘A species is a group of actually or potentially interbreeding natural populations which is reproductively isolated from other such groups’. He called this the Biological Species Concept.

This definition of species, still widely accepted, has frequently been misinterpreted as meaning that ‘different species cannot interbreed’. It does not say this. In the first place, it refers to species as ‘natural populations’. It is referring to what happens in a state of nature, not what happens in zoos or in domestic animals. For example, lions and leopards, which although closely related are usually recognised as different species, live in the same habitats in Africa and India and, as far as I know, no authenticated hybrids are known from the wild. But in zoos, hybrids have been bred successfully.

Then there is the question of what exactly ‘reproductive isolation’ consists of. Mayr said that the mechanisms of reproductive isolation may be either pre-mating (where members of different species do not normally regard each other as potential mates) or post-mating (where they do mate, but the hybrids do not survive, or are sterile). In the case of lions and leopards, evidently the reproductive isolating mechanisms are pre-mating, because normally they do not regard each other as potential mates, but these can break down if a male of one species and a female of the other are caged together, a case of making the best of a bad job, if you like. Their post-mating reproductive isolation, however, is incomplete: male lion-leopard hybrids are thought to be sterile, but the females are fertile.

So far so good. According to the Biological Species Concept, different species are defined by not usually forming hybrids with each other, for whatever reason, under natural conditions. But it is not so simple.

Consider leopards, again. They live not only in Africa and India, but also on the island of Sri Lanka, and throughout Southeast Asia, including the island of Java. The leopards of Sri Lanka and Java obviously do not interbreed with those of the mainland, because they are separated by water barriers. According to Ernst Mayr’s definition, species are ‘actually or potentially interbreeding natural populations’, and presumably island leopards are to be regarded as ‘potentially interbreeding’ with mainland ones. But how do we know? How could we possibly know?

birds

© J. Dougherty

The closest relative of the lion and the leopard is the jaguar, which lives in South and Central America, and likewise doesn’t have the chance to interbreed with leopards (or with lions, for that matter), so again, the ‘potentially interbreeding’ criterion breaks down. I would ask, and it is legitimate to ask, why is the jaguar classified as a species separate from the African and mainland-Asian leopard, whereas the Sri Lankan and Javanese leopards are not?

In my opinion, ‘potentially interbreeding’, is, really, a phantom concept. The Biological Species Concept offers no guidance at all for deciding whether populations living in different areas are distinct species or not. As one example from my own experience, mammal specialists have had heated discussions over whether the American bison and the European bison are or are not different species, a particularly pointless exercise if one accepts the Biological Species Concept. It was as early as the 1960s that a few taxonomists began to worry about this, because they were starting to realise that there were quite a lot of cases where they really needed to know. Gilbert’s potoroo, from the south-west of Western Australia, is it, or is it not, a different species from the Long-nosed potoroo, from south-eastern Australia? This may sound like a piece of pedantry, but it is in fact not a trivial decision, because Gilbert’s potoroo is critically endangered, and if it is not really a distinct species then it is less of a worry.

It was a group working in the American Museum of Natural History, known as the New York Group and already getting a reputation for asking awkward questions, that was pushing most strongly for a resolution, and in 1983, one of them, the ornithologist Joel Cracraft, proposed to replace the Biological Species Concept altogether and define a species ‘The smallest cluster of individual organisms within which there is a parental pattern of ancestry and descent, and that is diagnosably distinct from other such clusters by a unique combination of fixed character states’. What this means is that a species is a population or group of populations (this is the ‘parental pattern of ancestry and descent’ bit) which can be distinguished 100% from any other (this is the ‘diagnosably distinct’ bit). This concept of species is called the Phylogenetic Species Concept.

Many biologists, myself included, I’m afraid, started off by disliking the Phylogenetic Species Concept, and hoped it would die a natural death. But it did not; in fact it spread because many biologists, including taxonomists, and at long last I too, realised that it provides an objective criterion, diagnosability, for all cases, which the old Biological Species Concept does not. It tells us, for example, that Sri Lankan and Javanese leopards are not distinct species, because they cannot be 100% distinguished from the leopards of the mainland, whereas the jaguar is a distinct species because it is 100% distinct from its relatives.

© P. Mays

© P. Mays

Much taxonomy today depends on molecular genetics, DNA sequencing. At present, many molecular geneticists tend to distinguish species rather subjectively, if they differ ‘enough’, though what is meant by ‘enough difference’ varies from one study to another. The Phylogenetic Species Concept is of course excellently suited to DNA sequencing, and many species have been recognised by having consistent differences in DNA sequences (the diagnosability criterion).

The molecular revolution has also taught us something important about species, that they do in fact interbreed under natural conditions, to a much greater extent than we had thought. We know this, because there is a form of DNA, mitochondrial DNA, that is inherited not from both parents, but from the mother alone; it is passed solely down the female line (with apparently few exceptions). And we now know quite a number of cases where a population of one species has the mitochondrial DNA of a different, related species.

Here is a nice example. The common deer species of the eastern United States is the white-tailed deer. In the west, it is replaced by the mule deer, and in the middle they live side-by-side in the same habitats. On a large ranch in West Texas, there are herds of both species, and they have the same mitochondrial DNA! There has been some dispute in the past over whose mitochondrial DNA it actually is, but it now appears that it is that of the mule deer. We imagine that, at some time in the past, some white-tailed bucks, unable to find does of their own species, ‘made the best of a bad job’ and drove off some mule deer bucks and mated with mule deer does. Hybrids were born, and in the next generation more white-tail bucks came over and mated with them. The hybrids are now three-quarters white-tail, and one-quarter mule deer, but of course they still had the mitochondrial DNA of their mule deer grandmothers. In a few more generations, they would come to totally resemble white-tailed deer, the only legacy of their original maternal heritage being their mitochondrial DNA.





Ice: canary in the global coal mine

14 09 2009

An intended pun from James Balog in another classic TED talk. If you thought climate change was merely a prediction from mathematical models, think again. The biodiversity implications are staggering.

“We have a problem of perception… Not enough people really get it yet.” J. Balog

Vodpod videos no longer available.
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Coming to grips with the buffalo problem

7 09 2009

Clive McMahon (left) & colleaguesA good friend and colleague of mine, Dr. Clive McMahon, is visiting Adelaide for the next few weeks from Darwin. We’re attacking a few overdue manuscripts and sampling a few of Adelaide’s better drops of value-added grape juice, so I asked him to do a guest post on ConservationBytes.com about his work. So here it is, something perhaps even few Australians know much about, let alone overseas folks. If you can recall that very strange scene in the film Crocodile Dundee where the old croc hunter casts a gestured spell over a horned beast, then you’ll probably appreciate this post.

Yes, there are plenty of them in northern Australia

Invasive and feral species can be important drivers of biodiversity loss. Australia, like many other isolated islands has developed an ancient, unique and diverse ecosystem. This unique ecosystem has been under extreme pressure ever since humans arrived around 40000-60000 years ago. One of the more damaging and economically important introduced species in Australia is the Asian swamp buffalo (Bubalus bubalis). Ironically, swamp buffalo are listed as Endangered by the IUCN, and current estimates suggest that there are probably less than 4000 in their native habitats in Asia.

© B. Salu, Kakadu National Park

© B. Salau, Kakadu National Park

The first 16 buffalo were introduced to Australia in 1826 on Melville Island, and then to the mainland at Cobourg Peninsula a year later from Kupang (now West Timor, Indonesia). Another 18 buffalo were obtained from Kisar Island (northeast of modern Timor-Leste) and introduced to the Cobourg. In 1843, another 49 were introduced. When the first Cobourg settlement was abandoned in 1849, all the buffalo were released, and the population spread rapidly throughout the Northern Territory. Over the next 65 years, numbers and distribution increased to an estimated 350000 in the 1960s and 1970s and densities exceeded 25 km-2 in ‘prime’ habitat. However, the population was severely reduced during the 1980s and 1990s in parts of its range under the Brucellosis-Tuberculosis Eradication Campaign (BTEC). Although largely successful in eradicating buffalo from pastoral lands in the short term, there was no ongoing broad-scale management of numbers and the present-day population of free-ranging buffalo has recovered to former densities in some areas.

© C. Speed

© C. Speed

Buffalo were then and still are major problem in Australia due mainly to the environmental damage they cause, such as saltwater intrusion of wetlands and trampling of sensitive habitats, their potential threat to Australia’s livestock industry as hosts for disease, and the danger they pose to human safety. Given these ecological, economic and social impacts, there is an urgent need to manage buffalo numbers.

An important step to inform management of introduced and invasive species is to determine the history of introduction and quantify the rate of spread from introduction sites. Contemporary genetic techniques in conjunction with demographic and life history information are useful tools for understanding the dynamics, population structure, biology and colonisation dynamics of plants and animals, including invasive species such as buffalo.

We are currently in the final stages of providing the first detailed analysis of the buffalo population structure (demographic and genetic) to (1) establish the rate and most probable history of spread using detailed genetic information sampled from 8 sub-populations, (2) quantify the genetic distance and mixing rates between populations and (3) describe the age structure and therefore the demographic performance of this very successful invasive species.

Firstly to get an idea of genetic structure and relatedness, we collected a total of 430 small skin biopsies from buffalo across the Northern Territory, representing eight geographically distinct populations. To determine what has made the buffalo such a successful invader it is important to know the survival and breeding performance; we also constructed seven life tables based on culled samples at different densities and in different environments to work out what are the critical components of the population – i.e., where management intervention would be most successful.

As expected from a bottlenecked population, genetic variation is low compared to the that found in swamp buffalo from India and South East Asia. Despite this reduced genetic variation, the Australian population has thrived and spread outwards from introduction sites and into culled sites at high rates over the last 160 years (covering ~ 224 000 km2 in that time).

Although buffalo in Australia experienced two major periods of population reduction since their introduction, a small proportion (estimated at ~ 20 %) escaped the BTEC reduction in the eastern part of its north Australian range. BTEC did not operate with uniformity across the entire range of buffalo, concentrating its destocking efforts in a general area from the western coast of the Northern Territory to west of the Mann River in Arnhem Land, and south roughly to Kakadu National Park’s southern border. Coincidently and not surprisingly, it is in this area that we observe most migration activity.

The subpopulation structure detected here suggests that each population, while connected over generational time scales, generally remains in its immediate vicinity over the course of management-tractable periods. Therefore, management aimed at protecting Australia’s lucrative livestock industry trading under Australia’s disease-free status will benefit directly from this knowledge. For example, the localised introduction and subsequent rapid detection of disease could be efficiently managed from local culls because short-term movements of long-distance are less likely. Our results showcase how management of animals for disease control can be effectively informed via genetic studies and so avoid the need for expensive broad-scale intervention.

Our analyses of the age structure of buffalo reveals that buffalo have the capacity to recover swiftly after control because of high survival and fertility rates. Survival in the juvenile age classes was consistently the most important modifier of population growth. In populations where juvenile animals are harvested annually, fertility determined rebound potential. Thus, management aimed at long-term control of densities should focus primarily on the sustained culling of adult females and their offspring.

Given that numbers of buffalo are increasing and that buffalo are extremely well-adapted to the monsoonal tropics (unlike cattle, buffalo can maintain body condition and positive growth during times of food shortages), they are vulnerable to extended periods of harsh conditions. Climate change predictions herald increasing rainfall in the region, thereby potentially reducing the pressure on juvenile survival. As such, buffalo population growth could conceivably increase, making future management much more difficult. In essence, we need a large, evidence-based density reduction programme in place soon to prevent the worst ecological damage to Australia’s sensitive and unique ecosystems.

Check back here for announcements of upcoming publications arising from our work.

Clive McMahon & CJA Bradshaw

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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

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Wobbling to extinction

31 08 2009

crashI’ve been meaning to highlight for a while a paper that I’m finding more and more pertinent as a citation in my own work. The general theme is concerned with estimating extinction risk of a particular population, species (or even ecosystem), and more and more we’re finding that different drivers of population decline and eventual extinction often act synergistically to drive populations to that point of no return.

In other words, the whole is greater than the sum of its parts.

In other, other words, extinction risk is usually much higher than we generally appreciate.

This might seem at odds with my previous post about the tendency of the stochastic exponential growth model to over-estimate extinction risk using abundance time series, but it’s really more of a reflection of our under-appreciation of the complexity of the extinction process.

In the early days of ConservationBytes.com I highlighted a paper by Fagan & Holmes that described some of the few time series of population abundances right up until the point of extinction – the reason these datasets are so rare is because it gets bloody hard to find the last few individuals before extinction can be confirmed. Most recently, Melbourne & Hastings described in a paper entitled Extinction risk depends strongly on factors contributing to stochasticity published in Nature last year how an under-appreciated component of variation in abundance leads to under-estimation of extinction risk.

‘Demographic stochasticity’ is a fancy term for variation in the probability of births deaths at the individual level. Basically this means that there will be all sorts of complicating factors that move any individual in a population away from its expected (mean) probability of dying or reproducing. When taken as a mean over a lot of individuals, it has generally been assumed that demographic stochasticity is washed out by other forms of variation in mean (population-level) birth and death probability resulting from vagaries of the environmental context (e.g., droughts, fires, floods, etc.).

‘No, no, no’, say Melbourne & Hastings. Using some relatively simple laboratory experiments where environmental stochasticity was tightly controlled, they showed that demographic stochasticity dominated the overall variance and that environmental variation took a back seat. The upshot of all these experiments and mathematical models is that for most species of conservation concern (i.e., populations already reduced below to their minimum viable populations size), not factoring in the appropriate measures of demographic wobble means that most people are under-estimating extinction risk.

Bloody hell – we’ve been saying this for years; a few hundred individuals in any population is a ridiculous conservation target. People must instead focus on getting their favourite endangered species to number at least in the several thousands if the species is to have any hope of persisting (this is foreshadowing a paper we have coming out shortly in Biological Conservationstay tuned for a post thereupon).

Melbourne & Hastings have done a grand job in reminding us how truly susceptible small populations are to wobbling over the line and disappearing forever.

CJA Bradshaw

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Not-so-scary maths and extinction risk

27 08 2009
© P. Horn

© P. Horn

Population viability analysis (PVA) and its cousin, minimum viable population (MVP) size estimation, are two generic categories for mathematically assessing a population’s risk of extinction under particular environmental scenarios (e.g., harvest regimes, habitat loss, etc.) (a personal plug here, for a good overview of general techniques in mathematical conservation ecology, check out our new chapter entitled ‘The Conservation Biologist’s Toolbox…’ in Sodhi & Ehrlich‘s edited book Conservation Biology for All by Oxford University Press [due out later this year]). A long-standing technique used to estimate extinction risk when the only available data for a population are in the form of population counts (abundance estimates) is the stochastic exponential growth model (SEG). Surprisingly, this little beauty is relatively good at predicting risk even though it doesn’t account for density feedback, age structure, spatial complexity or demographic stochasticity.

So, how does it work? Well, it essentially calculates the mean and variance of the population growth rate, which is just the logarithm of the ratio of an abundance estimate in one year to the abundance estimate in the previous year. These two parameters are then resampled many times to estimate the probability that abundance drops below a certain small threshold (often set arbitrarily low to something like < 50 females, etc.).

It is simple (funny how maths can become so straightforward to some people when you couch them in words rather than mathematical symbols), and rather effective. This is why a lot of people use it to prescribe conservation management interventions. You don’t have to be a modeller to use it (check out Morris & Doak’s book Quantitative Conservation Biology for a good recipe-like description).

But (there’s always a but), a new paper just published online in Conservation Letters by Bruce Kendall entitled The diffusion approximation overestimates extinction risk for count-based PVA questions the robustness when the species of interest breeds seasonally. You see, the diffusion approximation (the method used to estimate that extinction risk described above) generally assumes continuous breeding (i.e., there are always some females producing offspring). Using some very clever mathematics, simulation and a bloody good presentation, Kendall shows quite clearly that the diffusion approximation SEG over-estimates extinction risk when this happens (and it happens frequently in nature). He also offers a new simulation method to get around the problem.

Who cares, apart from some geeky maths types (I include myself in that group)? Well, considering it’s used so frequently, is easy to apply and it has major implications for species threat listings (e.g., IUCN Red List), it’s important we estimate these things as correctly as we can. Kendall shows how several species have already been misclassified for threat risk based on the old technique.

So, once again mathematics has the spotlight. Thanks, Bruce, for demonstrating how sound mathematical science can pave the way for better conservation management.

CJA Bradshaw

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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

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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

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Continuing saga of the frogs’ legs trade

10 08 2009
© D. Bickford

© M. Auliya

In January we had a flurry of media coverage (see here for examples) about one of our papers that had just come out online in Conservation BiologyEating frogs to extinction (Warkentin et al.). I blogged about the paper then (one of ConservationBytes’ most viewed posts) that described the magnitude of the global trade in amphibian parts for human food. Suffice it to say, it’s colossal.

A couple of months ago, John Henley of the Guardian (UK) rang me to discuss the issue some more for a piece he was doing in that newspaper. The article has just come out (along with a companion blog post), and I can honestly say that it’s the most insightful coverage of the issue by the media I’ve seen yet. Thanks, John, for covering it so well. The article is excellently written, poignant and really gets to the heart of the matter – people just don’t know how bad the frog trade really is for amphibian biodiversity.

Short story – don’t eat any more frogs’ legs (you probably won’t be missing much).

I’ve reproduced John’s article below, but please visit the original here.

Why we shouldn’t eat frogs’ legs

In the cavernous community hall of the Vosges spa town of Vittel, a large and lugubrious man, his small, surprisingly chirpy wife, and 450 other people are sitting down to their evening meal. It’s rather noisy. “Dunno why we do it, really,” shouts the man, whose name is Jacky. “Don’t taste of anything, do they? White. Insipid. If it wasn’t for the sauce it’d be like eating some soft sort of rubber. Just the kind of food an Englishman should like, in fact. Hah.”

Outside, the streets are filled with revellers. A funfair is going full swing. The restaurants along the high street are full, and queues have formed before the stands run by the local football, tennis, basketball, rugby and youth clubs.

All offer the same thing: cuisses de grenouilles à la provencale (with garlic and parsley), cuisses de grenouille à la poulette (egg and cream). Seven euros, or thereabouts, for a paper plateful, with fries. Nine with a beer or a glass of not-very-chilled riesling. The more daring are offering cuisses de grenouilles à la vosgienne, à l’andalouse, à l’ailloli. There’s pizza grenouille, quiche grenouille, tourte grenouille. Omelette de grenouilles aux fines herbes. Souffle, cassolette and gratin de grenouilles.

Everywhere you look, people are nibbling greasily on a grenouille, licking their fingers, spitting out little bones. “Isn’t it just great?” yells Jacky’s diminutive wife, Frederique. “Every year we do this. It’s our tradition. Our tribute to the noble frog.”

This is Vittel’s 37th annual Foire aux Grenouilles. According to Roland Boeuf, the 70-year-old president of the Confrererie de Taste-Cuisses de Grenouilles de Vittel, or (roughly) the Vittel Brotherhood of Frog Thigh Tasters, which has organised the event since its inception, the fair regularly draws upwards of 20,000 gourmet frog aficionados to the town for two days of amphibian-inspired jollities. Between them, they consume anything up to seven tonnes of frogs’ legs.

But there’s a problem. When the fair began, its founder René Clément, resistance hero, restaurateur and last of the great Lorraine frog ranchers, could supply all the necessary amphibians from his lakes 20 miles or so away. Nowadays, none of the frogs are even French.

According to Boeuf, Clément, whose real name was Hofstetter, moved to the area in the early 1950s looking to raise langoustines in the Saone river; the water proved too brackish and he turned to frogs instead. A true Frenchman, his catchphrase, oft-quoted around these parts, was that frogs “are like women. The legs are the best bits”.

Hofstetter/Clément would, says Gisèle Robinet, “provide 150 kg, 200 kg for every fair, all from his lakes and all caught by him”. With her husband Patrick, Robinet runs the Au Pêché Mignon patisserie (tourte aux grenouilles for six, €18; chocolate frogs €13 the dozen) on the Place de Gaulle, across the square from the restaurant Clément used to run, Le Grand Cerf. Now known as Le Galoubet, there’s a plaque commemorating the great frogman outside. “As a child I remember clearly him dismembering and preparing and cleaning his frogs in front of the restaurant,” says Robinet, who sells frog tartlets to gourmet Vitellois throughout the year, but makes a special effort with quiches and croustillants at fair-time. “It’s a big job, you know. Very fiddly. But we were all frog-catchers when I was a kid. Now, of course, that’s not possible any more.”

Boeuf recalls many a profitable frog-hunting expedition in the streams and ponds around Vittel. “One sort, la savatte, you could catch with your bare hands,” he says. “Best time was in spring, when they lay their eggs. They’d gather in their thousands, great wriggling green balls of them. I’ve seen whole streams completely blocked by a mountain of frogs.”

Others, rainettes, would be everywhere at harvest time. Or you could get a square of red fabric and lay it carefully on the water next to a lily pad that happened to have a frog on it, “and she’d just hop straight off and on to the cloth”, Boeuf says. “They love red.”

Pierette Gillet, the longest-standing member of the Brotherhood and, at 81, still a sprightly and committed frog-fancier, remembers heading out at night with a torch in search of so-called mute frogs, harder to catch because they have no larynx and hence emit no croak. “They’d be blinded by the light, and you could whack them over the head,” she says.

But those days are long gone. As elsewhere in the world, the amphibians’ habitat in France – where frogs’ legs have been a recognised and much remarked-upon part of the national diet for the best part of 1,000 years – is increasingly at risk, from pollution, pesticides and other man-made ills. Ponds have been drained and replaced with crops and cattle-troughs. Diseases have taken their toll, and the insects that frogs feed on are disappearing too. Alarmed by a rapid and dramatic fall in frog numbers, the French ministry of agriculture and fisheries began taking measures to protect the country’s species in 1976; by 1980, commercial frog harvesting was banned.

These days, a few regional authorities in France still allow the capture of limited numbers of frogs, strictly for personal consumption and provided they are broiled, fried or barbecued and consumed on the spot (a heresy not even Boeuf is prepared to contemplate). There are poachers who defy the ban; two years ago a court in Vesoul in the Haute-Saone convicted four men of harvesting vast numbers of frogs from the Mille-Etangs or Thousand Lakes area of the Vosges. The ringleader admitted to personally catching at least 10,000, which he sold to restaurants for 32 cents apiece.

By and large, though, France’s tough protection laws, enforceable by fines of up to €10,000 (£8,500) and instant confiscation of vehicles and equipment, seem to be working. As a result, all seven tonnes (officially, at least) of frogs’ legs consumed at this year’s Vittel fair have been imported, pre-prepared, deep-frozen and packed in cardboard boxes, from Indonesia.

Needless to say, this does not much please patriotic Gallic frog-fanciers. “We’d far prefer our frogs to be French, of course we would,” laments Gillet. “Especially here in the Vosges. This really is the heart of frog country.”

A Vittel restaurateur, who for obvious reasons demands anonymity, suggests there are still “ways and means” of securing at least a semi-reliable supply of French frogs for those who demand a true produit du terroir, “but it’s really not very easy, and no one here will tell you anything about it. We’d like to source locally, but the law is the law.”

But the fact that the Foire aux Grenouilles – not to mention the rest of France, and other big frog-consuming nations such as Belgium and the United States – now imports almost all its frogs’ legs has consequences that run deeper than a mere denting of national gastronomic pride. For scientists now believe that, just as with many fish species, we could be well on the way to eating the world’s frogs to extinction. Based on an analysis of UN trade data, researchers think we may now be consuming as many as 1bn wild frogs every year. For already weakened frog populations, that is very bad news indeed.

Scientists have long been aware that while human activity is causing a steady loss of the world’s biodiversity, amphibians seem to be suffering far more severely than any other animal group. It is thought their two-stage life cycle, aquatic and terrestrial, makes them twice as vulnerable to environmental and climate change, and their permeable skins may be more susceptible to toxins than other animals. In recent years, a devastating fungal condition, chytridiomycosis, has caused catastrophic population declines in Australia and the Americas.

“Amphibians are the most threatened animal group; about one third of all amphibian species are now listed as threatened, against 23% of mammals and 12% of birds,” says Corey Bradshaw, an associate professor at the Environment Institute of the University of Adelaide and a member of the team that carried out the research into human frog consumption that was published earlier this year in the journal Conservation Biology. “The principle drivers of extinction, we always assumed, were habitat loss and disease. Human harvesting, we thought, was minor. Then we started digging, and we realised there’s this massive global trade that no one really knows much about. It’s staggering. So as well as destroying where they live, we’re now eating them to death.”

France is the main culprit: according to government figures, while the French still consume 70 tonnes a year of domestically gathered legs each year, they have been shipping in as many as 4,000 tonnes annually since 1995. Besides popular, essentially local events such as the Foire aux Grenouilles, frogs’ legs are mostly a delicacy reserved for restaurants with gastronomic pretensions; one three-star chef, Georges Blanc, has at one time or another developed 19 different recipes for them at his celebrated restaurant in the Ain village of Vonnas, baking and skewering and skilleting them in everything from cream to apples.

Belgium and Luxembourg are also noted connoisseurs, but perhaps surprisingly, the country that runs France closest in the frog import stakes is the US. Frogs’ legs are particularly popular in the former French colony of Louisiana, where the city of Rayne likes to call itself Frog Capital of the World, but are also consumed with relish in Arkansas and Texas, where they are mostly served breaded and deep-fried. Bradshaw has a picture on his blog of President Barack Obama tucking with apparent gusto into a plate of frogs’ legs.

The world’s most avid frog eaters, though, are almost certainly in Asia, in countries such as Indonesia, China, Thailand and Vietnam. South America, too, is a big market. “People may think frogs’ legs are some kind of epicurean delicacy consumed by a handful of French gourmets, but in many developing countries they are a staple,” Bradshaw says.

Indonesia is today the world’s largest exporter of frogs by far, shipping more than 5,000 tonnes each year. Some of these may be farmed, but not many. Commercial frog-farming has been tried in both the US and Europe, but with little success: for a raft of reasons, including the ease with which frogs can fall prey to disease, feeding issues and basic frog biology, it is a notoriously risky and uneconomic business. Frogs are farmed in Asia, but rarely on an industrial scale; most are small, artisan affairs with which rural families try to supplement their income.

The vast majority of frogs that end up on a plate are harvested from the wild. Bradshaw and his colleagues estimate that Indonesia, to take just one exporting country, is probably consuming between two and seven times as many frogs as it sends abroad. “We have the legally recorded, international trade figures, but none of the local business is recorded,” Bradshaw says. “It’s back-of-an-envelope work. That’s what’s so alarming.”

The scientists’ biggest concern, he says, is that because of the almost complete lack of data, no one knows in what proportion different frog species are being taken. If, as they suspect, some 15 or 20 frog species are at any given moment supplying most of world demand, the consequences could be catastrophic. For while overharvesting for human consumption may not in itself be quite enough to drive a frog species to extinction, combined with all the other threats frogs face it certainly could be.

“The thing is, it isn’t a gradual process,” Bradshaw warns. “There’s a threshold, you cross it, and the whole thing crashes because you’ve just completely changed the composition of the whole community. There’s a tipping point. It’s exactly what happened with the overexploitation of cod in the North Atlantic. And with frogs, there’s no data, no tracking, no stock management. We really should have learned our lesson with fish, but it seems we haven’t. This is a wake-up call.”

Back in Vittel, Boeuf says he had no idea frogs were in such trouble. “They’re an endangered species here, I know,” he says. “That’s why we have to be careful, and we are. But if we can buy them in such quantities from Indonesia, surely it must be all right. They’re being careful there too, aren’t they?” Sadly, it would seem they are not. And all for a few greasy scraps of limp, bland flesh.

People say frogs taste like a cross between fish and chicken. In fact, they taste of frog: in other words, precious little bar the sauce they are served in.





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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Few people, many threats – Australia’s biodiversity shame

31 07 2009

bridled_nailtail_400I bang on a bit about human over-population and how it drives biodiversity extinctions. Yet, it isn’t always hordes of hungry humans descending on the hapless species of this planet  – Australia is a big place, but has few people (just over 20 million), yet it has one of the higher extinction rates in the world. Yes, most of the country is covered in some fairly hard-core desert and most people live in or near the areas containing the most species, but we have an appalling extinction record all the same.

A paper that came out recently in Conservation Biology and was covered a little in the media last week gives some telling figures for the Oceania region, and more importantly, explains that we have more than enough information now to implement sound, evidence-based policy to right the wrongs of the past and the present. Using IUCN Red List data, Michael Kingsford and colleagues (paper entitled Major conservation policy issues for biodiversity in Oceania), showed that of the 370 assessed species in Australia, 80 % of the threatened ones are listed because of habitat loss, 40 % from invasive species and 30 % from pollution. As we know well, it’s mainly habitat loss we have to control if we want to change things around for the better (see previous relevant posts here, here & here).

Kingsford and colleagues proceed to give a good set of policy recommendations for each of the drivers identified:

Habitat loss and degradation

  • Implement legislation, education, and community outreach to stop or reduce land clearing, mining, and unsustainable logging through education, incentives, and compensation for landowners that will encourage private conservation
  • Establish new protected areas for habitats that are absent or poorly represented
  • In threatened ecosystems (e.g., wetlands), establish large-scale restoration projects with local communities that incorporate conservation and connectivity
  • Establish transparent and evidence-based state of environment reporting on biodiversity and manage threats within and outside protected areas.
  • Protect free-flowing river systems (largely unregulated by dams, levees, and diversions) within the framework of the entire river basin and increase environmental flows on regulated rivers

Invasive species

  • Avoid deliberate introduction of exotic species, unless suitable analyses of benefits outweigh risk-weighted costs
  • Implement control of invasive species by assessing effectiveness of control programs and determining invasion potential
  • Establish regulations and enforcement for exchange or treatment of ocean ballast and regularly implement antifouling procedures

Climate change

  • Reduce global greenhouse gas emissions
  • Identify, assess, and protect important climate refugia
  • Ameliorate the impacts of climate change through strategic management of other threatening processes
  • Develop strategic plans for priority translocations and implement when needed

Overexploitation

  • Implement restrictions on harvest of overexploited species to maintain sustainability
  • Implement an ecosystem-based approach for fisheries, based on scientific data, that includes zoning the ocean; banning destructive fishing; adopting precautionary fishing principles that include size limits, quotas, and regulation with sufficient resources based on scientific assessments of stocks and; reducing bycatch through regulation and education
  • Implement international mechanisms to increase sustainability of fisheries by supporting international treaties for fisheries protection in the high seas; avoiding perverse subsidies and improve labelling of sustainable fisheries; and licensing exports of aquarium fish
  • Control unsustainable illegal logging and wildlife harvesting through local incentives and cessation of international trade

Pollution

  • Decrease pollution through incentives and education; reduce and improve treatment of domestic, industrial, and agriculture waste; and rehabilitate polluted areas
  • Strengthen government regulations to stop generation of toxic material from mining efforts that affects freshwater and marine environments
  • Establish legislation and regulations and financial bonds (international) to reinforce polluter-pays principles
  • Establish regulations, education programs, clean ups, labelling, and use of biodegradable packaging to reduce discarded fishing gear and plastics

Disease

  • Establish early-detection programs for pathological diseases and biosecurity controls to reduce translocation
  • Identify causes, risk-assessment methods, and preventative methods for diseases
  • Establish remote communities of organisms (captive) not exposed to disease in severe outbreaks

Implementation

  • Establish regional population policies based on ecologically sustainable human population levels and consumption
  • Ensure that all developments affecting the environment are adequately analysed for impacts over the long term
  • Promote economic and societal benefits from conservation through education
  • Determine biodiversity status and trends with indicators that diagnose and manage declines
  • Invest in taxonomic understanding and provision of resources (scientific and conservation) to increase capacity for conservation
  • Increase the capacity of government conservation agencies
  • Focus efforts of nongovernmental organisations on small island states on building indigenous capacity for conservation
  • Base conservation on risk assessment and decision support
  • Establish the effectiveness of conservation instruments (national and international) and their implementation

A very good set of recommendations that I hope we can continue to develop within our governments.

CJA Bradshaw

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