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Influential conservation papers of 2022

3 01 2023

Following my annual tradition, I present the retrospective list of the ‘top’ 20 influential papers of 2022 as assessed by experts in Faculty Opinions (formerly known as F1000). These are in no particular order. See previous years’ lists here: 2021, 2020, 2019, 2018, 2017, 2016, 2015, 2014, and 2013.

Genetic variance in fitness indicates rapid contemporary adaptive evolution in wild animals — “… this paper adds a much-needed perspective to the status of genetic diversity and adaptive potential in contemporary populations.“

Habitat, geophysical, and eco-social connectivity: benefits of resilient socio-ecological landscapes — “… distinguishes four distinct but interrelated types of connectivity: landscape, habitat, geophysical, and eco-social connectivity, of which the fourth type is new. The authors discuss how these different types of connectivity are related to ecosystem services and disservices, and how they interact with each other to influence landscape sustainability issues.“

Glyphosate impairs collective thermoregulation in bumblebees — “… low-dose glyphosate, combined with global increases in temperature, converge to disrupt homeostatic regulation in bee colonies. This is a crucial revelation for understanding the loss of bees across the globe, as they serve as major pollinators in nature and agriculture.“

Human disturbances affect the topology of food webs — “… provides great opportunities for the study of food web structures, their dynamics and stability under different human influences.“

A comprehensive database of amphibian heat tolerance — “… provides estimates of amphibian upper thermal limits – a relevant trait for assessing the vulnerability of this highly-threatened group of ectotherms to rising temperatures – derived from thousands of experimental studies.”

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Categories : alien species, biodiversity, birds, climate change, climate shift, community ecology, connectivity, conservation, conservation biology, conservation ecology, coral reefs, deforestation, disease, ecology, ecosystem, ecosystem services, environmental policy, extinction, fish, fragmentation, frog, genetic diversity, genetics, habitat loss, invasive species, management, marine, marine protected area, modelling, monitoring, Murray-Darling, ocean, population dynamics, predator, protected area, recovery, research, restoration, science, seagrass, sustainability, synergies, threatened species, top-down ecology, trophic cascades, tropical, vegetation

Fancy a pangolin infected with coronavirus? Apparently, many people do

30 12 2021

The logic of money contradicts the logic of species conservation and human health. As illegal trade has driven pangolins to near extinction, their hunting and market value has kept increasing ― even when we have known that they act as coronavirus reservoirs in the middle of the Covid-19 pandemic.

_{Sunda pangolin (Manis javanica) in a monsoon forest (Sumba Island, Indonesia). With adult weights up to 10 kg and body lengths around half a metre, these animals are mostly solitary and nocturnal, feed on ants and termites, and love tree climbing using bark hollows to shelter and give birth to singletons. The species occurs across mainland and islands of South East Asia, and became ‘Endangered’ in 2008 and ‘Critically Endangered’ in 2014, following a 80% decline in the last 20 years due to hunting and poaching. It has been the most heavily trafficked Asian species, and the IUCN’s assessment states: “… the incentives for harvesting and illegally trading in the species are universally high based on the high financial value of pangolin parts and derivatives”. Captive breeding is unlikely to deter wild collection because (among other reasons) farming costs are high (more so on a large scale) and, even if the species could be traded legally, wild versus farmed pangolin products and individuals are difficult to distinguish (23). Photo courtesy of Michael Pitts}

Urbanites are attracted to exotic species, materials, and places. Our purchasing power seems to give us the right to buy any ‘object’ that we can pay for, no matter how exotic the object might be. In such a capitalist rationale, it is no surprise that > 150 thousand illegal cargos with wild animals and plants have been confiscated in 149 countries over the last two decades, moving some 6000 species from one place of the planet to another (1).

Social networks show people interacting with all kinds of fauna, creating the illusion that any animal can become a pet (2). And there’s a multi-$billion market of wildlife for a diverse array of uses including collecting, food, ornamentation, leisure, clothing and medicine (3-5). The paradox is that the rarer a species is, the higher its market value runs and the more lucrative selling it turns out to be, leading to more exploitation and rocketing extinction risk (6).

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Tags: CITES, COVID, COVID-19, covid19, endangered, illegal wildlife trade, pangolin, SARS-COV-2, wildlife, Wildlife trade
Categories : Africa, Asia, biodiversity, China, conservation, conservation biology, corruption, decline, disease, economics, environmental policy, exploitation, extinction, harvest, Malaysia, mammal, poaching, poverty, South East Asia, threatened species, tropical

Remote areas not necessarily safe havens for biodiversity

16 12 2021

The intensity of threats to biodiversity from human endeavour becomes weaker as the distance to them increases.

As you move away from the big city to enjoy the countryside, you’ll notice the obvious increase in biodiversity. Even the data strongly support this otherwise subjective perception — there is a positive correlation between the degree we destroy habitat, harvest species, and pollute the environment, and the distance from big cities.

Remote locations are therefore usually considered safe havens and potential reservoirs for biodiversity. But our new study published recently in Nature Communications shows how this obvious pattern depicts only half of the story, and that global conservation management and actions might benefit from learning more about the missing part.

Communities are not just lists of individual species. Instead, they consist of complex networks of ecological interactions linking interdependent species. The structure of such networks is a fundamental determinant of biodiversity emergence and maintenance. However, it also plays an essential role in the processes of biodiversity loss. The decline or disappearance of some species might have detrimental —often fatal — effects on their associates. For example, a parasite cannot survive without its hosts, as much as a predator will starve without prey, or a plant will not reproduce without pollinators.

Events where a species disappears following the loss of other species on which it depends are known as co-extinctions, and they are now recognised as a primary driver of the ongoing global biodiversity crisis. The potential risk stemming from ecological dependencies is a major concern for all ecological systems.

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Tags: climate change, coral reefs, coral-reef fishes, ecological networks, Fish, Giovanni Strona, Trophic cascade
Categories : biodiversity, bottom-up ecology, climate change, community ecology, connectivity, conservation, conservation biology, coral reefs, ecology, extinction, fish, fisheries, marine, marine protected area, modelling, planning, predation, predator, top-down ecology, tropical

How much is that iguana in the window?

25 08 2020

In our latest study, we examine the downstream effects of publicising an elevated species description for a reptile that is highly prized in the international commercial wildlife trade.

We describe how iguanas from an insular population of the common green iguana (Iguana iguana) entered commercial trade shortly after an announcement was made indicating that the population would be described as a new species.

The international commercial wildlife trade presents a known risk factor for wild populations of threatened species. One organisation in particular regulates the international trade in species — the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).

Although most people probably know about the illegal practices involving iconic elephants and rhinos, reptiles are also targeted and traded. For example, after its discovery and description in 2016, and even though locality data were safeguarded, China’s endemic Mountain spiny crocodile newt (Echinotriton maxiquadratus) quickly entered the trade. This put conservation pressure on this small-range species (1, 2). Therefore, CITES signatory countries placed this species on its Appendix II in 2019, which lists animals and plants in need of protection.

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Tags: CITES, Convention on International Trade in Endangered Species of Wild Fauna and Flora, iguana, Saba, Saba black dragon, Wildlife trade
Categories : alien species, captive breeding, conservation, conservation biology, environmental policy, exploitation, tropical

Successful movers responding to climate change

16 06 2020

tropical fishes range shifts Ecologists often rely on measuring certain elements of a species’ characteristics, behaviour, or morphology to determine if these — what we call ‘traits’ — give them certain capacities to exploit their natural environments. While sometimes a bit arbitrarily defined, the traits that can be measured are many indeed, and sometimes they reveal rather interesting elements of a species’ resilience in the face of environmental change.

As we know, climate change is changing the way species are distributed around the planet, for the main (and highly simplified) reason that the environments in which they’ve evolved and to which they have adapted are changing.

In the simplest case, a warming climate means that there is a higher and higher chance you’ll experience temperatures that really don’t suit you that well (think of a koala or a flying fox baking in a tree when the thermometer reads +45° in the shade). Just like you seeking those nice, air-conditioned spaces on a scorcher of a day, species like to move to where conditions are more acceptable to their particular physiologies and behaviours.

When they can’t change fast enough, they go extinct.

Ecologists use life-history traits to predict which species have the highest probability of moving to new areas in response to climate change. Most studies into this phenomenon have largely ignored that range shifts in fact occur in sequential stages: (1) the species arrives in a new place for the first time, (2) its population increases in size (and extent), and (3) it can continue to persist in the new spot. Read the rest of this entry »

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Tags: Biogeography, climate change, Fish, marine fishes, native invasive species, range shifts, species' traits, traits, tropical fish
Categories : alien species, Australia, behaviour, bioclimatic envelope, biogeography, climate change, climate shift, coasts, community ecology, coral reefs, ecology, ecosystem, extinction, fish, food, function, invasive species, marine, monitoring, southern Australia, tropical

Academics and Indigenous groups unite to stand up for the natural world

26 04 2019

Rain forest gives way to pastures in the Brazilian Amazon in Mato Grosso. Photo by Thiago Foresti.

More than 600 scientists from every country in the EU and 300 Brazilian Indigenous groups have come together for the first time. This is because we see a window of opportunity in the ongoing trade negotiations between the EU and Brazil. In a Letter published in Science today, we are asking the EU to stand up for Brazilian Indigenous rights and the natural world. Strong action from the EU is particularly important given Brazil’s recent attempts to dismantle environmental legislation and ‘develop the unproductive Amazon’.

It’s worth clarifying — this isn’t about the EU trying to control Brazil — it’s about making sure our imports aren’t driving violence and deforestation. Foreign white people trying to ‘protect nature’ abroad have a dark and shameful past, where actions done in the name of conservation have led to the eviction of millions of Indigenous people. This has predominantly been to create (what we in the world of conservation would call) ‘protected areas’. The harsh reality is that most protected areas either are or have been ancestral lands of Indigenous people who are closely linked to their land and depend on it for their survival. Clearly, conservationists need to support Indigenous people. This new partnership between European scientists and Brazilian Indigenous groups is doing just that.

Brazil’s forest loss 2001-2013 shown in red. Indigenous lands outlined. By Mike Clark; data from GlobalForestWatch.org

In Brazil, many Indigenous groups still have a right to their land. This land is predominantly found in the Amazon rainforest, where close to a million Indigenous people live and depend on a healthy forest. Indigenous people are some of the best protectors of this vast forest, and are crucial to a future of long-term successful conservation. But Brazilian Indigenous groups and local communities are increasingly under attack. Violence on deforestation frontiers in Brazil has spiked this month, with at least 9 people found dead. The future is particularly scary for Indigenous people when there are quotes such as this from the man who is currently the President “It’s a shame that the Brazilian cavalry hasn’t been as efficient as the Americans, who exterminated the Indians.”

On top of human rights and environmental concerns, there is a strong profit driven case for halting deforestation. For example, ongoing deforestation in the Amazon risks flipping large parts of the rainforest to savanna – posing a serious risk to agricultural productivity, food security, local livelihoods, and the Brazilian economy. Zero-deforestation doesn’t harm agri-business, it allows for its longevity. Read the rest of this entry »

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Tags: agricultural expansion, agriculture, Brazil, carbon footprint, Cerrado, deforestation, EU, European Union, eviction, feed, genocide, indigenous, livestock, livestock feed, native people, Pantanal, Protected Areas, rain forest, Rainforest, savanna, violence
Categories : agriculture, Amazon, anthropocene, biodiversity, biowealth, carbon, cattle, climate change, conservation, corruption, decline, deforestation, development, ecosystem services, environmental policy, Europe, extinction, food, fragmentation, governance, habitat loss, harvest, livestock, logging, rain forests, reserve, South America, sustainability, tropical, vegetation

A call to wings

19 03 2019

This week sees the launch of an updated bat synopsis from Conservation Evidence, adding new studies that have come out since the first synopsis was published in 2013.

The synopsis collects and summarises studies that test conservation actions such as ‘provide bat boxes for roosting bats’, and organises the studies by the action that they test. This focus on solutions makes it a handy point of reference for conservationists wishing to see what might work — and what is unlikely to work — to conserve bats.

Bechstein’s bat – photo credit Claire Wordley

Bechstein’s bat (Myotis bechsteinii) — photo credit Claire Wordley

Free to read or download from Conservation Evidence, the update represents a major addition to the original, containing 173 studies to the original 101. Studies are included if they tested an action that could be put in place for conservation, and measured an outcome for bats. As well as adding studies published from 2013 on, the update adds studies originally published in Spanish or Portuguese, and it is hoped that more languages will be added in future editions. Read the rest of this entry »

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Tags: agri-environment schemes, agroforestry, Barbastella barbastellus, bats, chauve-souris, conservation evidence, Cynopterus brachyotis, development, evidence, fledermaus, flying foxes, gantries, green bridges, megabats, Megachiroptera, microbats, Microchiroptera, mitigation, murcielago, Myotis bechsteinii, Myotis dasycneme, pipistrella, Plecotus auritus, restoration, underpasses, United Kingdom, wildlife crossings, wire and ball
Categories : agriculture, biodiversity, conservation, development, environmental policy, environmental science, habitat loss, human-wildlife conflict, mammal, management, monitoring, science, South America, tropical

A life of fragmentation

9 05 2018

Laurance What do you say to a man whose list of conservation awards reads like a Star Wars film intro, who has introduced terms like the ‘hyperdynamism hypothesis’ to the field of ecology, and whose organisation reaches over one million people each week with updates of the scientific kind?

Interview with Bill Laurance by Joel Howland (originally published in Conjour)

—
Well, I started by asking what it is that leads him to love the natural world to the extent he does. His answer was disarmingly simple.

“I grew up in the country, on an Oregon cattle ranch, and I think my love of nature just evolved naturally from that. When I was a young kid my dad and I did some fishing and ‘rock-hounding’— searching for rare stones and fossils. As an adolescent and teen I loved heading off into a forest or wilderness, rifle in hand – back in those days you could do that – to see whatever I could find. I watched red foxes hunting, eagles mating, and even heard a mountain lion scream. I got to be a pretty good duck and game-bird hunter.”

He’s quick to point out, however, he realised his taste for guns was not so developed as his love of nature.

“I gave up my rifles for a camera, and enjoyed that even more. I really got into photography for a while. Nature has always just calmed and fascinated me —I guess that’s partly why I became a conservationist.”

Who is Bill Laurance?

William F. Laurance is one of the leading ecology and conservation scientists globally, publishing dozens of papers in journals like Nature and Science, and rewriting the way scientists in the field research the complex interactions between flora and fauna — particularly in rainforests like the Amazon.

He is a Distinguished Research Professor at James Cook University in Australia, a Fellow of the Australian Academy of Science and the American Association for the Advancement of Science, and has received an Australian Laureate Fellowship from the Australian Research Council.

All this for a man from western USA who dreamed of running a zoo. Instead, he has travelled a path of intricate and game-changing research, trailblazing awareness campaigns and inspirational writings that have driven the way many see the environment over the past few decades.

Despite this profile, Laurance gave some time to tell Conjour about his life, his passion and his aims. I asked him what — considering his impressive CV — the future holds.

His response seems a real insight to the man. Read the rest of this entry »

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Tags: Bill Laurance, conservation, conservation biology, fragmentation, roads, William Laurance
Categories : Amazon, anthropocene, Asia, Australia, biodiversity, Central America, climate change, connectivity, conservation, conservation biology, conservation ecology, conservation scholars, deforestation, development, environmental policy, environmental science, extinction, fragmentation, governance, habitat loss, harvest, logging, protected area, research, reserve, roads, science, South America, tropical

Drivers of protected-area effectiveness in Africa

31 01 2018

Bowker_et_al-2017-Conservation_Biology. Fig. 1

Subtropical and
Tropical Moist Broadleaf Forest of
Africa with 224 parks surrounded
by a 10-km buffer area. ©
2016 Society for Conservation Biology.

I’ve just read an interesting paper published in late 2016 in Conservation Biology that had so far escaped my attention. But given my interest in African conservation recently (and some interesting research results on the determinants of environmental performance for that region should be coming soon out of our lab), the work caught my eye.

The paper by Bowker and colleagues asked a question that has been asked previously regarding the ‘effectiveness’ of protected areas — do they succeed in limiting forest loss? While forest loss itself is not necessarily indicative of biodiversity erosion in any given area (for that, you need measures of species trends, etc.), it is arguably one of the most important drivers of species loss today.

The first set out to differentiate ‘effective’ from ‘ineffective’ protected areas, which was a simple binary variable related to whether there was less deforestation inside the protected area relative to comparable points outside (effective), or greater than or equal to deforestation outside (ineffective). The authors then related this binary response to a series of biophysical and social indicators. Read the rest of this entry »

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Tags: Africa, biodiversity, conservation, deforestation, effectiveness, forest loss, national parks, paper parks, parks, Protected Areas
Categories : Africa, conservation, deforestation, fragmentation, governance, logging, management, protected area, rain forests, tropical

Giving a monkey’s about primate conservation

12 12 2017

Urban monkey living (Macaque, Gibraltar) small

Concrete jungle. A Barbary macaque sits in a human-dominated landscape in Gibraltar. Photo: Silviu Petrovan

Saving primates is a complicated business. Primates are intelligent, social animals that have complex needs. They come into conflict with humans when they raid rubbish bins and crops, chew power cables, and in some cases become aggressive towards people.

Humans, however, have the upper hand. While 60% of non-human primate species are threatened, humans grow in numbers and power, building roads through forests, hunting and trapping primates, and replacing their habitat with farms and houses.

To help primatologists choose the most effective conservation approaches to resolve these problems, researchers in the Conservation Evidence project teamed up with primate researchers to produce a global database on the effectiveness of primate conservation solutions. This free database, which can also be downloaded as a single pdf, summarizes the evidence for 162 conservation interventions — actions that conservationists might take to conserve primates. The data come from searches of over 170 conservation journals and newsletters, and each study is summarized in a single paragraph in plain English, making it possible for conservationists without access to scientific journals to read the key findings.

So what works in primate conservation? Well, the picture is rarely straightforward — partly due to the lack of data — but there are some interesting trends. Reducing hunting is one area where there seem to be a range of potentially effective approaches. Community control of patrolling, banning hunting and removing snares was effective in the three studies in which it was tested, all in African countries.

Further emphasizing the importance of involving local communities, implementing no-hunting community policies or traditional hunting bans also appeared helpful in boosting primate numbers. In other places, a more traditional approach of using rangers to protect primates has proved a winning strategy. Training rangers, providing them with arms, and increasing ranger patrols all worked to protect primates from poachers. Identifying the circumstances in which community led approaches or ranger patrols work will be key to implementing the most appropriate response to each conservation challenge. Read the rest of this entry »

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Tags: conservation evidence, conservation intervention, hunting, macaques, monkey, primates, PRISM toolkit
Categories : biodiversity, conservation, conservation biology, decline, deforestation, development, education, environmental policy, exploitation, extinction, habitat loss, harvest, implementation, logging, management, monitoring, planning, research, restoration, software, threatened species, tropical

Microclimates: thermal shields against global warming for small herps

22 11 2017

Thermal microhabitats are often uncoupled from above-ground air temperatures. A study focused on small frogs and lizards from the Philippines demonstrates that the structural complexity of tropical forests hosts a diversity of microhabitats that can reduce the exposure of many cold-blooded animals to anthropogenic climate warming.

Reproductive pair of the Luzon forest frogs Platymantis luzonensis (upper left), a IUCN near-threatened species restricted to < 5000 km² of habitat. Lower left: the yellow-stripped slender tree lizard Lipinia pulchella, a IUCN least-concerned species. Both species have body lengths < 6 cm, and are native to the tropical forests of the Philippines. Right panels, top to bottom: four microhabitats monitored by Scheffers et al. (2), namely ground vegetation, bird’s nest ferns, phytotelmata, and fallen leaves above ground level. Photos courtesy of Becca Brunner (Platymantis), Gernot Kunz (Lipinia), Stephen Zozaya (ground vegetation) and Brett Scheffers (remaining habitats).

If you have ever entered a cave or an old church, you will be familiar with its coolness even in the dog days of summer. At much finer scales, from centimetres to millimetres, this ‘cooling effect’ occurs in complex ecosystems such as those embodied by tropical forests. The fact is that the life cycle of many plant and animal species depends on the network of microhabitats (e.g., small crevices, burrows, holes) interwoven by vegetation structures, such as the leaves and roots of an orchid epiphyte hanging from a tree branch or the umbrella of leaves and branches of a thick bush.

Much modern biogeographical research addressing the effects of climate change on biodiversity is based on macroclimatic data of temperature and precipitation. Such approaches mostly ignore that microhabitats can warm up or cool down in a fashion different from that of local or regional climates, and so determine how species, particularly ectotherms, thermoregulate (1). To illustrate this phenomenon, Brett Scheffers et al. (2) measured the upper thermal limits (typically known as ‘critical thermal maxima’ or CTmax) of 15 species of frogs and lizards native to the tropical forest of Mount Banahaw, an active volcano on Luzon (The Philippines). The > 7000 islands of this archipelago harbour > 300 species of amphibians and reptiles (see video here), with > 100 occurring in Luzon (3).

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Tags: amphibious, climate change, frogs, Global warming, herpetology, microclimates, thermal shield
Categories : amphibian, behaviour, biodiversity, carbon, climate change, climate shift, conservation biology, decline, ecology, extinction, frog, function, research, science, threatened species, trophic cascades, tropical

Four decades of fragmentation

27 09 2017

fragmented

I’ve recently read perhaps the most comprehensive treatise of forest fragmentation research ever compiled, and I personally view this rather readable and succinct review by Bill Laurance and colleagues as something every ecology and conservation student should read.

The ‘Biological Dynamics of Forest Fragments Project‘ (BDFFP) is unquestionably one of the most important landscape-scale experiments ever conceived and implemented, now having run 38 years since its inception in 1979. Indeed, it was way ahead of its time.

Experimental studies in ecology are comparatively rare, namely because it is difficult, expensive, and challenging in the extreme to manipulate entire ecosystems to test specific hypotheses relating to the response of biodiversity to environmental change. Thus, we ecologists tend to rely more on mensurative designs that use existing variation in the landscape (or over time) to infer mechanisms of community change. Of course, such experiments have to be large to be meaningful, which is one reason why the 1000 km² BDFFP has been so successful as the gold standard for determining the effects of forest fragmentation on biodiversity.

And successful it has been. A quick search for ‘BDFFP’ in the Web of Knowledge database identifies > 40 peer-reviewed articles and a slew of books and book chapters arising from the project, some of which are highly cited classics in conservation ecology (e.g., doi:10.1046/j.1523-1739.2002.01025.x cited > 900 times; doi:10.1073/pnas.2336195100 cited > 200 times; doi:10.1016/j.biocon.2010.09.021 cited > 400 times; and doi:10.1111/j.1461-0248.2009.01294.x cited nearly 600 times). In fact, if we are to claim any ecological ‘laws’ at all, our understanding of fragmentation on biodiversity could be labelled as one of the few, thanks principally to the BDFFP. Read the rest of this entry »

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Tags: Amazon, BDFFP, Biological Dynamics of Forest Fragments Project, Brazil, edge effects, extinction, extirpation, fragmentation, rarity, South America, synergies
Categories : Allee effect, Amazon, anthropocene, biodiversity, biowealth, carbon, climate change, community ecology, connectivity, conservation, conservation biology, conservation ecology, decline, deforestation, demography, development, drought, ecosystem, ecosystem function, endemic, endemism, environmental policy, exploitation, extinction, extinction debt, fire, flood, fragmentation, habitat loss, invasive species, logging, management, metapopulation, monitoring, population dynamics, population viability analysis, protected area, recovery, research, reserve, South America, tropical

It’s not all about temperature for corals

31 05 2017

Three of the coral species studied by Muir (2): (a) Acropora pichoni: Pohnpei Island, Pacific Ocean — deep-water species/IUCN ‘Near threatened’; (b) Acropora divaricate: Maldives, Indian ocean — mid-water species/IUCN ‘Near threatened’; and (c) Acropora gemmifera: Orpheus Island, Australia — shallow-water species/IUCN ‘Least Concern’. The IUCN states that the 3 species are vulnerable to climate change (acidification, temperature extremes) and demographic booms of the invading predator, the crown-of-thorns starfish Acanthaster planci. Photos courtesy of Paul Muir.

Global warming of the atmosphere and the oceans is modifying the distribution of many plants and animals. However, marine species are bound to face non-thermal barriers that might preclude their dispersal over wide stretches of the sea. Sunlight is one of those invisible obstacles for corals from the Indian and Pacific Oceans.

If we were offered a sumptuous job overseas, our professional success in an unknown place could be limited by factors like cultural or linguistic differences that have nothing to do with our work experience or expertise. If we translate this situation into biodiversity terms, one of the best-documented effects of global warming is the gradual dispersal of species tracking their native temperatures from the tropics to the poles (1). However, as dispersal progresses, many species encounter environmental barriers that are not physical (e.g., a high mountain or a wide river), and whose magnitude could be unrelated to ambient temperatures. Such invisible obstacles can prevent the establishment of pioneer populations away from the source.

Corals are ideal organisms to study this phenomenon because their life cycle is tightly geared to multiple environmental drivers (see ReefBase: Global Information System for Coral Reefs). Indeed, the growth of a coral’s exoskeleton relies on symbiotic zooxanthellae (see video and presentation), a kind of microscopic algae (Dinoflagellata) whose photosynthetic activity is regulated by sea temperature, photoperiod and dissolved calcium in the form of aragonite, among other factors.

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Tags: biodiversity, climate change, climate disruption, Coral, coral reefs, corals, distribution, extinction, Global warming, marine, ocean
Categories : Australia, bioclimatic envelope, biodiversity, biogeography, climate change, climate shift, conservation, coral reefs, ecology, extinction, invasive species, ocean, research, tropical

Noses baffled by ocean acidification

18 04 2017

Clown fish couple (Amphiprion percula) among the tentacles of anemone Heteractis magnifica in Kimbe Bay (Papua New Guinea) – courtesy of Mark McCormick. Clownfish protect anemones from predators and parasites in exchange of shelter and food. The fish tolerates the host’s venom because its skin is protected by a mucus layer some 2-3× thicker than phylogenetically related species (12); clownfish fabricate the mucus themselves and seem to obtain anemone antigens through a period of acclimation (13), but whether protection is acquired or innate is still debated. Clownfish are highly social bony fish, forming groups with one reproductive pair (up to 11 cm in length each) and several smaller, non-reproductive males. Reproduction is protandrous (also known as sequential hermaphroditism), so larvae are born male and, as soon as the reproductive female dies, her widower becomes female and the largest of the subsidiary males becomes the alpha male. The IUCN lists clownfish, generically named ‘anemone fish’, as threatened by the pet-trade industry and habitat degradation, although surprisingly, only 1 species has been assessed (A. sandaracinos). The clown anemone fish A. ocellaris is the species that inspired Nemo in the 2003 Academy-Award fiction movie – contrary to the logical expectation that the Oscars Red Carpet would generate support for conservation on behalf of Hollywood, of the 1568 species represented in the movie, only 16 % of those evaluated are threatened (14).

Smell is like noise, the more scents we breathe in one sniff, the more difficult it is to distinguish them to the point of olfactory saturation. Experimental work with clownfish reveals that the increase in dissolved carbon dioxide in seawater, mimicking ocean acidification, alters olfactory physiology, with potential cascading effects on the demography of species.

Places such as a restaurant, a hospital or a library have a characteristic bouquet, and we can guess the emotional state of other people by their scents. Smell is critical between predators and prey of many species because both have evolved to detect each other without the aid of vision. At sea, the smell of predators dissolves in water during detection, attack, capture, and ingestion of prey, and many fishes use this information to assess the risk of ending up crunched by enemy teeth (1, 2). But predator-prey interactions can be modified by changes in the chemical composition of seawater and are therefore highly sensitive to ongoing ocean acidification (see global measuring network here). Experts regard ocean acidification as the ‘other CO₂ problem’ of climate change (3) — just to emphasize that anthropogenic climate-change impacts terrestrial and aquatic ecosystems alike. Acidification occurs because the ocean absorbs CO₂ at a rate proportional with the concentration of this gas in the atmosphere and, once dissolved, CO₂ becomes carbonic acid (H₂CO₃), which in turn releases protons (H⁺) — in simple terms, pH is the concentration of protons (see video about ocean acidification): Read the rest of this entry »

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Tags: acidification, anemone, behavioural shift, Carbon dioxide, climate change, clown fish, Global warming, Nemo, odour, olfaction, physiology, scent, smell
Categories : acidification, behaviour, biodiversity, carbon, climate change, climate shift, conservation biology, decline, demography, development, ecology, extinction, fish, function, marine, ocean, predation, predator, research, threatened species, tropical

Limited nursery replenishment in coral reefs

27 03 2017

blue-striped grunt (Haemulon sciurus)

Coral reef fishes are wonderfully diverse in size, form, and function, as well as their need for different habitats throughout the life cycle. Some species spend all of their life in the same kind of coral habitat, while others need different places to breed and feed.

Fishes requiring different habitats as they progress through life often have what we call ‘nurseries’ in which adults lay eggs and the subsequent juveniles remain, and these places are often dominated by mangroves or seagrasses (i.e., they are not part of the coral reef).

While we’ve known for quite some time that when these nursery habitats are not around, adjacent coral reefs have few, if any, of these nursery-dependent species. What we haven’t known until now is just how far the influence of nurseries extends along a coral reef.

In other words, if a nursery is present, just how many new recruits do different areas of a reef receive from it? Read the rest of this entry »

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Tags: connectivity, coral reefs, coral-reef fishes, Fish, mangroves, nurseries, replenishment
Categories : biodiversity, community ecology, connectivity, conservation, conservation biology, coral reefs, demography, ecology, ecosystem function, exploitation, fish, fisheries, fragmentation, management, marine, marine protected area, seagrass, tropical

Singin’ in the heat

9 03 2017

Common coqui frog male (Eleutherodactylus coqui, snout-to vent length average ~ 3 cm) camouflaged in the fronds of an epiphyte in the El Yunque National Forest (Puerto Rico), along with an image of the enchanted forest of the Sierra de Luquillo where Narins & Meenderink did their study (4) – photos courtesy of Thomas Fletcher. This species can be found from sea level to the top of the highest peak in Puerto Rico (Cerro Punta = 1338 m). Native to mesic ecosystems, common coquis are well adapted to a terrestrial life, e.g., they lack interdigital webbing that support swimming propulsion in many amphibians, and youngsters hatch directly from the egg without transiting a tadpole stage. The IUCN catalogues the species as ‘Least Concern’ though alerts recent declines in high-altitude populations caused by chytrid fungus – lethal to amphibians at a planetary scale (9). Remarkably, the species has been introduced to Florida, Hawaii, the Dominican Republic and the Virgin Islands where it can become a pest due to high fertility rates (several >20 egg clutches/female/year).

Frog songs are species-specific and highly useful for the study of tropical communities, which host the highest amphibian diversities globally. The auditory system of females and the vocal system of males have co-evolved to facilitate reproductive encounters, but global warming might be disrupting the frequency of sound-based encounters in some species..

It is a rainy night, and Don (Gene Kelly) has just left his love, Kathy (Debbie Reynolds), at home, starting one of the most famous musical movie scenes ever: Singin’ in the rain …

Amphibians (see Amphibians for kids by National Geographic) also love to sing in rainy nights when males call for a partner, but now they have to do it in hotter conditions as local climates become warmer. Vocal behaviour is a critical trait in the life history of many frog species because it mediates recognition between individuals, including sexual selection by females (1).

With few exceptions, every species has a different and unique call, so scientists can use call features to identify species, and this trait is particularly useful in the inventory of diverse tropical communities (2). Differences in call frequency, duration and pitch, and in note, number, and repetition pattern, occur from one species to another. And even within species, songs can vary from individual to individual (as much as there are not two people with the same voice), and be tuned according to body size and environmental temperature (3). Read the rest of this entry »

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Tags: amphibians, behavioural shift, calls, climate change, Global warming, vocalisation
Categories : amphibian, behaviour, bioclimatic envelope, biodiversity, climate change, climate shift, decline, extinction, function, rain forests, research, South America, tropical

Tropical forest resilience depends on past disturbance frequency

16 07 2014

I’ve recently come across an interesting study that perfectly marries palaeo-ecological data with modern conservation philosophy. It’s not often that such a prehistorical perspective dating at least to the Last Glacial Maximum has been used so effectively to inform future conservation outlooks. I’m particularly interested in this sort of approach considering my own palaeo dabblings of late.

Published in Nature Communications this May, Lydia Cole and colleagues’ paper Recovery and resilience of tropical forests after disturbance is a meta-analysis of 71 studies covering nearly 300 disturbance events in tropical forests over the last 20,000 years or so. Using fossil pollen records as an index of vegetation change, they demonstrated the (somewhat intuitive) main result that the time to recovery following a disturbance generally decreases as the past disturbance frequency increased.

This appears to be a vindication of the idea that a system’s adaptive strategies evolve as a product of the local disturbance regime. More importantly, they found that recovery was faster following ‘large infrequent events’, which are natural perturbations such as cyclones and major fires. While most past disturbances were caused by humans clearing forest, the fact that tropical forest systems were most resilient to ‘natural’ events means that if we can’t stop human disturbances, at least we can attempt to emulate natural processes to maximise the rebound potential. Much like many modern forestry operations try to emulate natural disturbances to limit their damage, we should at least manage our impacts by understanding so-called ‘natural’ regimes as much as possible. Read the rest of this entry »

Comments : 1 Comment »
Tags: deforestation, disturbance, Forest, recovery, resilience, restoration
Categories : Africa, agriculture, Amazon, biodiversity, climate change, conservation, deforestation, ecology, flood, habitat loss, logging, management, recovery, reforestation, research, tropical

If biodiversity is so important, why is Europe not languishing?

17 03 2014

I don’t often respond to many comments on this blog unless they are really, really good questions (and if I think I have the answers). Even rarer is devoting an entire post to answering a question. The other day, I received a real cracker, and so I think it deserves a highlighted response.

Two days ago, a certain ‘P. Basu’ asked this in response to my last blog post (Lose biodiversity and you’ll get sick):

I am an Indian who lived in Germany for quite a long period. Now, if I am not grossly mistaken, once upon a time Germany and other west european countries had large tracts of “real” forests with bears, wolves, foxes and other animals (both carnivore and herbivore). Bear has completely disappeared from these countries with the advent of industrialization. A few wolves have been kept in more or less artificially created forests. Foxes, deer and hares, fortunately, do still exist. My question is, how come these countries are still so well off – not only from the point of view of economy but also from the angle of public health despite the loss of large tracts of natural forests? Or is it that modern science and a health conscious society can compensate the loss of biodiversity.

“Well”, I thought to myself, “Bloody good question”.

I have come across this genre of question before, but usually under more hostile circumstances when an overtly right-wing respondent (hell, let’s call a spade a spade – a ‘completely selfish arsehole’) has challenged me on the ‘value of nature’ logic (I’m not for a moment suggesting that P. Basu is this sort of person; on the contrary, he politely asked an extremely important question that requires an answer). The comeback generally goes something like this: “If biodiversity is so important, why aren’t super-developed countries wallowing in economic and social ruin because they’ve degraded their own life-support systems? Clearly you must be wrong, Sir.”

There have been discussions in the ecological and sustainability literature that have attempted to answer this, but I’ll give it a shot here for the benefit of CB.com readers. Read the rest of this entry »

Comments : 11 Comments »
Tags: biodiversity, biowealth, decline, Economics, ecosystem services, society
Categories : agriculture, anthropocene, Asia, Australia, biodiversity, Central America, China, conservation, decline, deforestation, disease, economics, ecosystem services, environmental policy, extinction, extinction debt, food, habitat loss, health, human overpopulation, pollution, poverty, South America, tropical

Incentivise to keep primary forests intact

7 02 2014

The Amazon rainforest. Photo by Rhett A. Butler

I know – ‘incentivise’ is one of those terrible wank words of business speak. But to be heard by the economically driven, one must learn their guttural and insensitive language. I digress …

Today’s post is merely a repost of an interview I did for the new Mongabay.com series ‘Next Big Idea in Forest Conservation‘. I’m honoured to have been selected for an interview along with the likes of Bill Laurance and Stuart Pimm.

Consider this my conservation selfie.

An Interview with Corey Bradshaw

Mongabay.com: What is your background?

Corey Bradshaw: I have a rather eclectic background in conservation ecology. I grew up in the wilds of western Canada, the son of a trapper. My childhood experiences initially gave me a primarily consumptive view of the environment from trapping, fishing and hunting, but I learned that without intact environmental functions, these precious resources quickly degrade or disappear. This ironic appreciation of natural processes would later lead me into academia and the pursuit of reducing the rate of the extinction crisis.

I completed my first degrees in ecology in Montréal and the University of Alberta, followed by a PhD in New Zealand at the University of Otago. After deciding to pursue the rest of my career in the Southern Hemisphere, I completed my postdoctoral fellowship at the University of Tasmania. Multiple field seasons in the subantarctic and Antarctica probably assisted in a giving me a burgeoning desire to change gears, so I left for the tropics of northern Australia to begin a position at Charles Darwin University. Being introduced there to conservation greats like Navjot Sodhi (sadly, now deceased), Barry Brook and David Bowman turned my research interests on their ear. I quickly became enamoured with quantitative conservation ecology, applying my skills in mathematics to the plight of the world’s ecosystems. Nowhere did the problems seem more intractable than in the tropics.

I am now based at the University of Adelaide (since 2008) and have a vibrant research lab where we apply our quantitative skills to everything from conservation ecology, climate change, energy provision, human population trends, ecosystem services, sustainable agriculture, human health, palaeoecology, carbon-based conservation initiatives and restoration techniques.

Mongabay.com: How long have you worked in tropical forest conservation and in what geographies? What is the focus of your work? Read the rest of this entry »

Comments : 8 Comments »
Tags: conservation, Corey Bradshaw, finance, forestry, forests, iREDD, primary forest, REDD, tropics
Categories : Amazon, Asia, carbon, carbon trading, climate change, conservation, conservation biology, deforestation, ecosystem function, ecosystem services, fragmentation, habitat loss, harvest, logging, Malaysia, oil palm, palm oil, rain forests, REDD, reforestation, reserve, tropical

More species = more resilience

8 01 2014

While still ostensibly ‘on leave’ (side note: Does any scientist really ever take a proper holiday? Perhaps a subject for a future blog post), I cannot resist the temptation to blog about our lab’s latest paper that just came online today. In particular, I am particularly proud of Dr Camille Mellin, lead author of the study and all-round kick-arse quantitative ecologist, who has outdone herself on this one.

Today’s subject is one I’ve touched on before, but to my knowledge, the relationship between ‘diversity’ (simply put, ‘more species’) and ecosystem resilience (i.e., resisting extinction) has never been demonstrated so elegantly. Not only is the study elegant (admission: I am a co-author and therefore my opinion is likely to be biased toward the positive), it demonstrates the biodiversity-stability hypothesis in a natural setting (not experimental) over a range of thousands of kilometres. Finally, there’s an interesting little twist at the end demonstrating yet again that ecology is more complex than rocket science.

Despite a legacy of debate, the so-called diversity-stability hypothesis is now a widely used rule of thumb, and its even implicit in most conservation planning tools (i.e., set aside areas with more species because we assume more is better). Why should ‘more’ be ‘better’? Well, when a lot of species are interacting and competing in an ecosystem, the ‘average’ interactions that any one species experiences are likely to be weaker than in a simpler, less diverse system. When there are a lot of different niches occupied by different species, we also expect different responses to environmental fluctuations among the community, meaning that some species inherently do better than others depending on the specific disturbance. Species-rich systems also tend to have more of what we call ‘functional redundancy‘, meaning that if one species providing an essential ecosystem function (e.g., like predation) goes extinct, there’s another, similar species ready to take its place. Read the rest of this entry »