Tropical biology and conservation overview

28 07 2010

Last week I attended the 2010 International Meeting of the Association for Tropical Biology and Conservation (ATBC) in Sanur, Bali (Indonesia). I only managed one post on the real-world relevance of conservation research (that attracted quite a lot of comment) while there, but I did promise to give a conference overview as I did for the International Congress for Conservation Biology earlier this month. So here goes.

This was my first ATBC meeting despite having co-written ‘the book’ on tropical conservation biology (well, one of very, very many). I no longer live in the tropics but am still managing to keep my hand in many different aspects of tropical research. After all, tropical regions represent ground zero for conservation biology – they have the highest biodiversity (no matter which way you measure it), some of the greatest threats (e.g., most people, most rapid development, most corruption) and some of the most pressing human problems (disease, hunger, socio-political instability). Ironically, most of the world’s conservation ecologists work in temperate realms – it should really be the other way around. Read the rest of this entry »





Interview with a social (conservation) scientist

22 06 2010

I was contacted recently by Josh Cinner, a self-titled ‘social’ scientist (now working at the Centre of Excellence for Coral Reef Studies) who has published rather a lot in the conservation literature. He was recently highlighted in the journal Science for his work, and he thought CB readers would enjoy the coverage. He stated to me:

“…as a social scientist, I have spent the past decade or so working with ecologists and managers trying to integrate social science better in conservation. There are often calls for the importance of integrating social science in conservation and I thought your blog readers might appreciate some high-level recognition of the importance of this. Additionally, as far as I can tell, this is the first of these profiles that has focused on someone working in conservation.”

So, while fully crediting the source of this article and its author, Helen Fields, here is the entire text reproduced for your reading pleasure.

In the late 1980s, things were not going well for the coral reefs at Jamaica’s Montego Bay Marine Park. Overfishing had taken out a lot of the fish that eat algae, and algae were taking over the reef. “It was a classic case of ecosystem decline,” human geographer Joshua Cinner says. He arrived in Jamaica in 1996 as a Peace Corps volunteer after graduating from the University of Colorado, Boulder, with a double major in environmental conservation and geography. He was particularly interested in parks and preserves.

He’d landed in the middle of a war. Lobbying by tour operators and others got spearfishing, one of the main culprits in overfishing, banned in the park. The ban did not go over well with local people. “All the park equipment got vandalized. We had park rangers get threatened; their families got threatened at spear point,” Cinner says. Spearfishing equipment is cheap and you don’t need a boat; men who do it are generally poor and are fishing as a last resort. “The cultural lens through which the fishermen viewed this issue was of struggle in a post-slavery society, of the rich, predominantly white expatriates making a law that oppressed the poorest of the poor locals to benefit the wealthy.”

The conflict got Cinner thinking about how conservation really works. “It wasn’t really about the ecology,” he says. “Making conservation work in Jamaica had a lot to do with understanding the local culture and people.” It also opened his eyes to the role oceans play. “The ocean is often viewed as an open-access resource. That extra layer of complexity interested me,” he says. “Land can often be private property,” but “the ocean is typically viewed as free for anyone to fish in, for anyone to swim in and use.” Read the rest of this entry »





Where in the world to invest in plant conservation

31 05 2010

© CBD

It’s been a good few weeks with many of our papers coming out online early – for example, I highlighted one last week on ecosystem function breakdown from global warming.

Although this has been out for a few weeks, our new paper lead by PhD candidate Xingli Giam (formerly of National University of Singapore, recently completed Australian Endeavour Scholar, now at Princeton University and all-round up-and-coming research star), and with contributions from Hugh “Vascular” Tan and Navjot Sodhi of National University of Singapore and me, is entitled Future habitat loss and the conservation of plant biodiversity (just published online in Biological Conservation).

This one is a bit of a complicated one, so let me walk you through it.

Plants not only represent a huge component of global biodiversity (~320 000 species), they represent the ‘habitats’ in which animals live and provide the major source of nutrients to food webs. They also provide most of our food and other materials essential for human existence. Basically we’d be screwed without them.

Because so many of the world’s biomes are severely threatened now because of massive habitat loss, degradation, over-exploitation, invasive species, extinction synergies and climate change, we need to maximise our efficiency in protecting what’s left. While global prioritisation schemes have a fruitful scientific history since Myers & colleagues’ classic paper (see Biodiversity Hotspots), there are a number of problems that plague the concept and its implementation. Read the rest of this entry »





February Issue of Conservation Letters

13 02 2010

Diver at Great Barrier Reef, Australia

Hard to believe we’re already at Volume 3 – introducing the latest issue of Conservation Letters (Volume 3, Issue 1, February 2010). For full access, click here.

Note too we’ve jumped from 5 to 6 papers per issue. Congratulations to all our authors. Keep those submissions coming!

CJA Bradshaw

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Parochial conservation

30 01 2010
© cagiecartoons.com

A little bit of conservation wisdom for you this weekend.

In last week’s issue of Nature, well-known conservation planner and all-round smart bloke, Reed Noss (who just happens to be an editor for Conservation Letters and Conservation Biology), provided some words of extreme wisdom. Not pulling any punches in his Correspondence piece entitled Local priorities can be too parochial for biodiversity, Noss essentially says ‘don’t leave the important biodiversity decisions to the locals’.

He argues rather strongly in his response to Smith and colleagues’ opinion piece (Let the locals lead) that local administrators just can’t be trusted to make good conservation decisions given their focus on local economic development and other political imperatives. He basically says that the big planning decisions should be made at grander scales that over-ride local concerns because, well, the big fish in their little ponds can’t be trusted (nor do they have the training) to do what’s best for regional biodiversity conservation.

I couldn’t agree more – he states:

“Academic researchers, conservation non-governmental organizations and other ‘foreign’ interests tend to be better informed, less subject to local political influence and more experienced in conservation planning than local agencies.”

Of course, being part of the first group, I’m probably a little biased, but I dare say that we’ve got a lot better handle on the science beyond saving biodiversity, as well as a better understanding of why that’s important, than your average regional representative, village council, chief, Lord Mayor or state member. Sure, ‘engage your stakeholders’ (I have images of shooting missiles at people holding star pickets with this gem of business jargon wankery, but there you go), but please base the decision on science first. I think Smith and colleagues have some good points, but I am more in favour of a broad-scale benevolent dictatorship in conservation planning than fine-scale democracy. Granted, the best formula is likely to be very context-specific, and of course, you need some people with local implementation power to make it happen.

Dear Honourable Minister, you may sign on the dotted line to make policy real, but please, please listen to us before you do. Your very life and those of your children depend on it.

CJA Bradshaw

ResearchBlogging.orgNoss, R. (2010). Local priorities can be too parochial for biodiversity Nature, 463 (7280), 424-424 DOI: 10.1038/463424a

Smith, R., Veríssimo, D., Leader-Williams, N., Cowling, R., & Knight, A. (2009). Let the locals lead Nature, 462 (7271), 280-281 DOI: 10.1038/462280a

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Conservation Biology for All

26 12 2009

A new book that I’m proud to have had a hand in writing is just about to come out with Oxford University Press called Conservation Biology for All. Edited by the venerable Conservation Scholars, Professors Navjot Sodhi (National University of Singapore) and Paul Ehrlich (Stanford University), it’s a powerhouse of some of the world’s leaders in conservation science and application.

The book strives to “…provide cutting-edge but basic conservation science to a global readership”. In short, it’s written to bring the forefront of conservation science to the general public, with OUP promising to make it freely available online within about a year from its release in early 2010 (or so the rumour goes). The main idea here is that those in most need of such a book – the conservationists in developing nations – can access the wealth of information therein without having to sacrifice the village cow to buy it.

I won’t go into any great detail about the book’s contents (mainly because I have yet to receive my own copy and read most of the chapters!), but I have perused early versions of Kevin Gaston‘s excellent chapter on biodiversity, and Tom Brook‘s overview of conservation planning and prioritisation. Our chapter (Chapter 16 by Barry Brook and me), is an overview of statistical and modelling philosophy and application with emphasis on conservation mathematics. It’s by no means a complete treatment, but it’s something we want to develop further down the track. I do hope many people find it useful.

I’ve reproduced the chapter title line-up below, with links to each of the authors websites.

  1. Conservation Biology: Past and Present (C. Meine)
  2. Biodiversity (K. Gaston)
  3. Ecosystem Functions and Services (C. Sekercioglu)
  4. Habitat Destruction: Death of a Thousand Cuts (W. Laurance)
  5. Habitat Fragmentation and Landscape Change (A. Bennett & D. Saunders)
  6. Overharvesting (C. Peres)
  7. Invasive Species (D. Simberloff)
  8. Climate Change (T. Lovejoy)
  9. Fire and Biodiversity (D. Bowman & B. Murphy)
  10. Extinctions and the Practice of Preventing Them (S. Pimm & C. Jenkins)
  11. Conservation Planning and Priorities (T. Brooks)
  12. Endangered Species Management: The US Experience (D. Wilcove)
  13. Conservation in Human-Modified Landscapes (L.P. Koh & T. Gardner)
  14. The Roles of People in Conservation (A. Claus, K. Chan & T. Satterfield)
  15. From Conservation Theory to Practice: Crossing the Divide (M. Rao & J. Ginsberg)
  16. The Conservation Biologist’s Toolbox – Principles for the Design and Analysis of Conservation Studies (C. Bradshaw & B. Brook)

As you can see, it’s a pretty impressive collection of conservation stars and hard-hitting topics. Can’t wait to get my own copy! I will probably blog individual chapters down the track, so stay tuned.

CJA Bradshaw

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Not so ‘looming’ – Anthropocene extinctions

4 11 2009

ABCclip031109

© ABC 2009

Yesterday I was asked to do a quick interview on ABC television (Midday Report) about the release of the 2009 IUCN Red List of Threatened Species. I’ve blogged about the importance of the Red List before, but believe we have a lot more to do with species assessments and getting prioritisation right with respect to minimum viable population size. Have a listen to the interview itself, and read the IUCN’s media release reproduced below.

My basic stance is that we’ve only just started to assess the number of species on the planet (under 50000), yet there are many millions of species still largely under-studied and/or under-described (e.g., extant species richness = > 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 – see Bradshaw & Brook 2009 J Cosmol for references). What we’re looking at here is a refinement of knowledge (albeit a small one). We are indeed in the midst of the Anthropocene mass extinction event – there is nothing ‘looming’ about it. We are essentially losing species faster than we can assess them. I believe it’s important to make this clearer to those not working directly in the field of biodiversity conservation.

CJA Bradshaw

Extinction crisis continues apace – IUCN

Gland, Switzerland, 3 November, 2009 (IUCN) – The latest update of the IUCN Red List of Threatened Species™ shows that 17,291 species out of the 47,677 assessed species are threatened with extinction.

The results reveal 21 percent of all known mammals, 30 percent of all known amphibians, 12 percent of all known birds, and 28 percent of reptiles, 37 percent of freshwater fishes, 70 percent of plants, 35 percent of invertebrates assessed so far are under threat.

“The scientific evidence of a serious extinction crisis is mounting,” says Jane Smart, Director of IUCN’s Biodiversity Conservation Group. “January sees the launch of the International Year of Biodiversity. The latest analysis of the IUCN Red List shows the 2010 target to reduce biodiversity loss will not be met. It’s time for governments to start getting serious about saving species and make sure it’s high on their agendas for next year, as we’re rapidly running out of time.”

Of the world’s 5,490 mammals, 79 are Extinct or Extinct in the Wild, with 188 Critically Endangered, 449 Endangered and 505 Vulnerable. The Eastern Voalavo (Voalavo antsahabensis) appears on the IUCN Red List for the first time in the Endangered category. This rodent, endemic to Madagascar, is confined to montane tropical forest and is under threat from slash-and-burn farming.

There are now 1,677 reptiles on the IUCN Red List, with 293 added this year. In total, 469 are threatened with extinction and 22 are already Extinct or Extinct in the Wild. The 165 endemic Philippine species new to the IUCN Red List include the Panay Monitor Lizard (Varanus mabitang), which is Endangered. This highly-specialized monitor lizard is threatened by habitat loss due to agriculture and logging and is hunted by humans for food. The Sail-fin Water Lizard (Hydrosaurus pustulatus) enters in the Vulnerable category and is also threatened by habitat loss. Hatchlings are heavily collected both for the pet trade and for local consumption.

“The world’s reptiles are undoubtedly suffering, but the picture may be much worse than it currently looks,” says Simon Stuart, Chair of IUCN’s Species Survival Commission. “We need an assessment of all reptiles to understand the severity of the situation but we don’t have the $2-3 million to carry it out.”

The IUCN Red List shows that 1,895 of the planet’s 6,285 amphibians are in danger of extinction, making them the most threatened group of species known to date. Of these, 39 are already Extinct or Extinct in the Wild, 484 are Critically Endangered, 754 are Endangered and 657 are Vulnerable.

The Kihansi Spray Toad (Nectophrynoides asperginis) has moved from Critically Endangered to Extinct in the Wild. The species was only known from the Kihansi Falls in Tanzania, where it was formerly abundant with a population of at least 17,000. Its decline is due to the construction of a dam upstream of the Kihansi Falls that removed 90 percent of the original water flow to the gorge. The fungal disease chytridiomycosis was probably responsible for the toad’s final population crash.

The fungus also affected the Rabb’s Fringe-limbed Treefrog (Ecnomiohyla rabborum), which enters the Red List as Critically Endangered. It is known only from central Panama. In 2006, the chytrid fungus (Batrachochytrium dendrobatidis) was reported in its habitat and only a single male has been heard calling since. This species has been collected for captive breeding efforts but all attempts have so far failed.

Of the 12,151 plants on the IUCN Red List, 8,500 are threatened with extinction, with 114 already Extinct or Extinct in the Wild. The Queen of the Andes (Puya raimondii) has been reassessed and remains in the Endangered category. Found in the Andes of Peru and Bolivia, it only produces seeds once in 80 years before dying. Climate change may already be impairing its ability to flower and cattle roam freely among many colonies, trampling or eating young plants.

There are now 7,615 invertebrates on the IUCN Red List this year, 2,639 of which are threatened with extinction. Scientists added 1,360 dragonflies and damselflies, bringing the total to 1,989, of which 261 are threatened. The Giant Jewel (Chlorocypha centripunctata), classed as Vulnerable, is found in southeast Nigeria and southwest Cameroon and is threatened by forest destruction.

Scientists also added 94 molluscs, bringing the total number assessed to 2,306, of which 1,036 are threatened. Seven freshwater snails from Lake Dianchi in Yunnan Province, China, are new to the IUCN Red List and all are threatened. These join 13 freshwater fishes from the same area, 12 of which are threatened. The main threats are pollution, introduced fish species and overharvesting.

There are now 3,120 freshwater fishes on the IUCN Red List, up 510 species from last year. Although there is still a long way to go before the status all the world’s freshwater fishes is known, 1,147 of those assessed so far are threatened with extinction. The Brown Mudfish (Neochanna apoda), found only in New Zealand, has been moved from Near Threatened to Vulnerable as it has disappeared from many areas in its range. Approximately 85-90 percent of New Zealand’s wetlands have been lost or degraded through drainage schemes, irrigation and land development.

“Creatures living in freshwater have long been neglected. This year we have again added a large number of them to the IUCN Red List and are confirming the high levels of threat to many freshwater animals and plants. This reflects the state of our precious water resources. There is now an urgency to pursue our effort but most importantly to start using this information to move towards a wise use of water resources,” says Jean-Christophe Vié, Deputy Head of the IUCN Species Programme.

“This year’s IUCN Red List makes for sobering reading,” says Craig Hilton-Taylor, Manager of the IUCN Red List Unit. “These results are just the tip of the iceberg. We have only managed to assess 47,663 species so far; there are many more millions out there which could be under serious threat. We do, however, know from experience that conservation action works so let’s not wait until it’s too late and start saving our species now.”

The status of the Australian Grayling (Prototroctes maraena), a freshwater fish, has improved as a result of conservation efforts. Now classed as Near Threatened as opposed to Vulnerable, the population has recovered thanks to fish ladders which have been constructed over dams to allow migration, enhanced riverside vegetation and the education of fishermen, who now face heavy penalties if found with this species.





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





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





Global conservation priorities based on human need

13 07 2009
nf2

© Wiley-Blackwell

A paper recently posted online in Conservation Letters caught my eye as a Potential on ConservationBytes.com.

Gary Luck and colleagues’ paper Protecting ecosystem services and biodiversity in the world’s watersheds is a novel approach to an admittedly problematic aspect of conservation biology – global prioritisation schemes. While certainly coming in as a Conservation Classic, the first real global conservation prioritisation scheme (Myers and colleagues’ global biodiversity hotspots) was rather subjective in its approach, and many subsequent schemes have failed to reproduce the same kinds of priorities (the congruency problem). I’m certainly not knocking biodiversity hotspots because I believe it was one of the true paradigm shifts in conservation biology, but I am cognisant of its limitations.

Another big problem with conservation prioritisation schemes is that they are a hard sell to governments – how do you convince nations (especially poor ones) to forgo the immediate gains of resource exploitation to protect what many (incorrectly and short-sightedly) deem as irrelevant centres of biotic endemism?

Well, Luck and colleagues have taken us one step closer to global acceptance of conservation prioritisation schemes by basing this latest addition on ecosystem services. In their paper they divided the world by catchments (watersheds) and then estimated the services of water provision, flood prevention and carbon storage that each provides to humanity. Water provision was a estimated as a complex combination of variables that together can be interpreted as the capacity of ecosystems to regulate water flows and quality that benefit humans (e.g., influencing seasonal water availability or nutrient levels). Flood mitigation was estimated as the system’s capacity to reduce the impact of floods on communities, and carbon storage was estimated as the system’s capacity to uptake carbon in soils and vegetation.

In general, the catchments in need of the highest priority protection were found in the poorest areas (namely, South East Asia and Africa) because their protection would be the least costly and benefit the most people. Luck and colleagues are therefore the first to incorporate cost–benefit trade-offs explicitly in developing global priorities for protecting ecosystem services and biodiversity. I take my hat off to them for a modern and highly relevant twist on an old idea. Great paper and I hope people take notice.

CJA Bradshaw

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Classics: Ecological Triage

27 03 2009

It is a truism that when times are tough, only the strongest pull through. This isn’t a happy concept, but in our age of burgeoning biodiversity loss (and economic belt-tightening), we have to make some difficult decisions.In this regard, I suggest Brian Walker’s1992 paper Biodiveristy and ecological redundancy makes the Classics list.

Ecological triage is, of course, taken from the medical term triage used in emergency or wartime situations. Ecological triage refers to the the conservation prioritisation of species that provide unique or necessary functions to ecosystems, and the abandonment of those that do not have unique ecosystem roles or that face almost certain extinction given they fall well below their minimum viable population size (Walker 1992). Financial resources such as investment in recovery programmes, purchase of remaining habitats for preservation, habitat restoration, etc. are allocated accordingly; the species that contribute the most to ecosystem function and have the highest probability of persisting are earmarked for conservation and others are left to their own devices (Hobbs & Kristjanson 2003).

This emotionally empty and accounting-type conservation can be controversial because public favourites like pandas, kakapo and some dolphin species just don’t make the list in many circumstances. As I’ve stated before, it makes no long-term conservation or economic sense to waste money on the doomed and ecologically redundant. Many in the conservation business apply ecological triage without being fully aware of it. Finite pools of money (generally the paltry left-overs from some green-guilty corporation or under-funded government initiative) for conservation mean that we have to set priorities – this is an entire discipline in its own right in conservation biology. Reserve design is just one example of this sacrifice-the-doomed-for-the good-of-the-ecosystem approach.

Walker (1992) advocated that we should endeavour to maintain ecosystem function first, and recommended that we abandon programmes to restore functionally ‘redundant’ species (i.e., some species are more ecologically important than others, e.g., pollinators, prey). But how do you make the choice? The wrong selection might mean an extinction cascade (Noss 1990; Walker 1992) whereby tightly linked species (e.g., parasites-hosts, pollinators-plants, predators-prey) will necessarily go extinct if one partner in the mutualism disappears (see Koh et al. 2004 on co-extinctions). Ecological redundancy is a terribly difficult thing to determine, especially given that we still understand relatively little about how complex ecological systems really work (Marris 2007).

The more common (and easier, if not theoretically weaker) approach is to prioritise areas and not species (e.g., biodiversity hotspots), but even the criteria used for area prioritisation can be somewhat arbitrary and may not necessarily guarantee the most important functional groups are maintained (Orme et al. 2005; Brooks et al. 2006). There are many different ways of establishing ‘priority’, and it depends partially on your predilections.

More recent mathematical approaches such as cost-benefit analyses (Possingham et al. 2002; Murdoch et al. 2007) advocate conservation like a CEO would run a profitable business. In this case the ‘currency’ is biodiversity, and so a fixed financial investment must maximise long-term biodiversity gains (Possingham et al. 2002). This essentially estimates the potential biodiversity saved per dollar invested, and allocates funds accordingly (Wilson et al. 2007). Where the costs outweigh the benefits, conservationists move on to more beneficial goals. Perhaps the biggest drawback with this approach is that it’s particularly data-hungry. When ecosystems are poorly measured, then the investment curve is unlikely to be very realistic.

CJA Bradshaw

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(Many thanks to Lochran Traill and Barry Brook for co-developing these ideas with me)








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