What we know we don’t know about animal tolerances to high temperatures

30 01 2023

Each organism has a limit of tolerance to cold and hot temperatures. So, the closer it lives to those limits, the higher the chances of experiencing thermal stress and potentially dying. In our recent paper, we revise gaps in the knowledge of tolerance to high temperatures in cold-blooded animals (ectotherms), a diverse group mostly including amphibians and reptiles (> 16,000 species), fish (> 34,000 species), and invertebrates (> 1,200,000 species).

As a scientist, little is more self-realising than to write and publish a conceptual paper that frames the findings of your own previous applied-research papers. This is the case with an opinion piece we have just published in Basic and Applied Ecology1 — 10 years, 4 research papers2-5 [see related blog posts here, here, here and here], and 1 popular-science article6 after I joined the Department of Biogeography and Global Change (Spanish National Research Council) to study the thermal physiology of Iberian lizards under the supervision of Miguel Araújo and David Vieites.

Iberian lizards for which heat tolerance is known (varying from 40 to 45 °C)
 
[left, top to bottom] Iberian emerald lizard (Lacerta schreiberi, from Alameda del Valle/Madrid) and Geniez’s wall lizard (Podarcis virescens, Fuertescusa/Cuenca), and [right, top to bottom] Algerian sand racer (Psammodromus algirus, Navacerrada/Madrid), Andalusian wall lizard (Podarcis vaucheri, La Barrosa/Cádiz), Valverde’s lizard (Algyroides marchi, Riópar/Albacete), and Cyren’s rock lizard (Iberolacerta cyreni, Valdesquí/Madrid). Heat-tolerance data deposited here and used to evaluate instraspecific variation of heat tolerance3,4. Photos: Salvador Herrando-Pérez.

In our new paper, we examine how much we know and what areas of research require further development to advance our understanding of how and why the tolerance of ectotherm fauna to high environmental temperature (‘heat tolerance’ hereafter) varies within and across the Earth’s biomes. We focus on data gaps using the global database GlobTherm as a reference template (see Box 1 below).

Our three main tenets

1. Population versus species data: Most large-scale ecophysiological research is based on modelling one measurement of heat tolerance per species (typically representing one population and/or physiological assay) over hundreds to thousands of species covering broad geographical, phylogenetic, and climatic gradients.

But there is ample evidence that heat tolerance changes a lot among populations occupying different areas of the distribution of a species, and such variation must be taken into account to improve our predictions of how species might respond to environmental change and face extinction.

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Categories : biodiversity, climate change, climate shift, conservation, conservation ecology, ecology, ecosystem services, extinction, research, science, threatened species

Interrupted flows in the Murray River endanger frogs

17 01 2023

Flooding in the Murray-Darling Basin is creating ideal breeding conditions for many native species that have evolved to take advantage of temporary flood conditions. Led by PhD candidate Rupert Mathwin, our team developed virtual models of the Murray River to reveal a crucial link between natural flooding and the extinction risk of endangered southern bell frogs (Litoria raniformis; also known as growling grass frogs).

Southern bell frogs are one of Australia’s 100 Priority Threatened Species. This endangered frog breeds during spring and summer when water levels increase in their wetlands. However, the natural flooding patterns in Australia’s largest river system have been negatively impacted by expansive river regulation that some years, sees up to 60% of river water extracted for human use.

Our latest paper describes how we built computer simulations of Murray-Darling Basin wetlands filled with simulated southern bell frogs. By changing the simulation from natural to regulated conditions, we showed that modern conditions dramatically increase the extinction risk of these beloved frogs.

The data clearly indicate that successive dry years raise the probability of local extinction, and these effects are strongest in smaller wetlands. Larger wetlands and those with more frequent inundation are less prone to these effects, although they are not immune to them entirely. The models present a warning — we have greatly modified the way the river behaves, and the modern river cannot support the long-term survival of southern bell frogs.’

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Categories : Australia, biodiversity, climate change, connectivity, conservation, demography, drought, ecology, environmental policy, extinction, flood, frog, management, metapopulation, minimum viable population, modelling, Murray River, Murray-Darling, population dynamics, population viability analysis, PVA, River Murray, South Australia, southern Australia, stochasticity, threatened species, water, weir gates

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

Children born today will see literally thousands of animals disappear in their lifetime, as global food webs collapse

17 12 2022
Frida Lannerstrom/Unsplash, CC BY

Corey J. A. Bradshaw, Flinders University and Giovanni Strona, University of Helsinki

Climate change is one of the main drivers of species loss globally. We know more plants and animals will die as heatwaves, bushfires, droughts and other natural disasters worsen.

But to date, science has vastly underestimated the true toll climate change and habitat destruction will have on biodiversity. That’s because it has largely neglected to consider the extent of “co-extinctions”: when species go extinct because other species on which they depend die out.

Our new research shows 10% of land animals could disappear from particular geographic areas by 2050, and almost 30% by 2100. This is more than double previous predictions. It means children born today who live to their 70s will witness literally thousands of animals disappear in their lifetime, from lizards and frogs to iconic mammals such as elephants and koalas.

But if we manage to dramatically reduce carbon emissions globally, we could save thousands of species from local extinction this century alone.

Ravages of drought will only worsen in coming decades.
CJA Bradshaw

An extinction crisis unfolding

Every species depends on others in some way. So when a species dies out, the repercussions can ripple through an ecosystem.

For example, consider what happens when a species goes extinct due to a disturbance such as habitat loss. This is known as a “primary” extinction. It can then mean a predator loses its prey, a parasite loses its host or a flowering plant loses its pollinators.

A real-life example of a co-extinction that could occur soon is the potential loss of the critically endangered mountain pygmy possum (Burramys parvus) in Australia. Drought, habitat loss, and other pressures have caused the rapid decline of its primary prey, the bogong moth (Agrotis infusa).

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Categories : anthropocene, biodiversity, bottom-up ecology, climate change, community ecology, connectivity, conservation, conservation biology, deforestation, ecology, ecosystem, endemism, environmental policy, extinction, habitat loss, mathematics, modelling, predation, research, science, top-down ecology, trophic cascades

Should we bring back the thylacine? We asked 5 experts

17 08 2022
Tasmanian Museum and Art Gallery

Signe Dean, The Conversation

In a newly announced partnership with Texas biotech company Colossal Biosciences, Australian researchers are hoping their dream to bring back the extinct thylacine is a “giant leap” closer to fruition.

Scientists at University of Melbourne’s TIGRR Lab (Thylacine Integrated Genetic Restoration Research) believe the new partnership, which brings Colossal’s expertise in CRISPR gene editing on board, could result in the first baby thylacine within a decade.

The genetic engineering firm made headlines in 2021 with the announcement of an ambitious plan to bring back something akin to the woolly mammoth, by producing elephant-mammoth hybrids or “mammophants”.

But de-extinction, as this type of research is known, is a highly controversial field. It’s often criticised for attempts at “playing God” or drawing attention away from the conservation of living species. So, should we bring back the thylacine? We asked five experts.

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Categories : Australia, biodiversity, climate change, cloning, conservation, conservation biology, conservation ecology, deforestation, ecology, ethics, extinction, genetic diversity, genetics, habitat loss, inbreeding depression, livestock, living dead, mammal, population viability analysis, science

Terror management

2 08 2022

As is my tendency, I like to wade carefully into other disciplines from time to time to examine what components they can bring to the conservation table. I do not profess any sort of expertise when I do so, but if I require a true expert for research purposes, then I will collaborate with said experts.

I often say to my students that in many ways, the science of sustainability and conservation is more or less resolved — what we need now is ways to manage the human side of the problems we face. The disciplines that deal with human management, such as psychology, economics, political science, and sociology, are mainly pursuits of the humanities (have I just argued myself out of a job?).

On the topic of human psychology, I think most people involved in some way with biodiversity conservation often contemplate why human societies are so self-destructive. Even in the face of logic and evidence, people deny what’s going on in front of their eyes (think anti-vaxxers, climate-change denialists, etc.), so it should be no wonder why many (most?) people deny their own existential threats. Yet, it still doesn’t seem to make much sense to us until we put the phenomenon into a psychological framework.

My apologies here to actual psychologists if I oversimplify or otherwise make mistakes, but the following explanation has done a lot for me personally in my own journey to understand this conundrum. It is also a good way to teach others about why there is so much reticence to fixing our environmental problems.

The idea is a rather simple one, but it requires a little journey to appreciate. Let’s pop back to the 1970s with the publication of Ernest Becker’s The Denial of Death, for which he won the Pulitzer Prize in 1974 (ironically, two months after his own death). In this book, Becker examined the awareness of death on human behaviour and the strategies that we have developed to mitigate our fear of it. This particular quote sums it up nicely:

This is the terror: to have emerged from nothing, to have a name, consciousness of self, deep inner feelings, and excruciating inner yearning for life and self expression — and with all this yet to die

Ernest Becker in The Denial of Death (1973)

The upshot is that we have evolved a whole raft of coping mechanisms to this personal existential dread. Some engage in overly hedonic pursuits to numb the anxiety; others try to “tranquillise themselves with the trivial”, essentially ignoring the terror, while others still manage the dread through religion and the hope of an existence beyond the mortal.

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Categories : biodiversity, climate change, conservation, ecology, economics, exploitation, extinction, extremism, management, science, societies, sustainability

Journal ranks 2021

4 07 2022

Now that Clarivate, Google, and Scopus have recently published their respective journal citation scores for 2021, I can now present — for the 14th year running on ConvervationBytes.com — the 2021 conservation/ecology/sustainability journal ranks based on my journal-ranking method.

Like last year, I’ve added a few journals. I’ve also included in the ranking the Journal Citation Indicator (JCI) in addition to the Journal Impact Factor and Immediacy Index from Clarivate ISI, and the CiteScore (CS) in addition to the Source-Normalised Impact Per Paper (SNIP) and SCImago Journal Rank (SJR) from Scopus. 

You can access the raw data for 2021 and use my RShiny app to derive your own samples of journal ranks.

I therefore present the new 2021 ranks for: (i) 106 ecology, conservation and multidisciplinary journals, (ii) 27 open-access (i.e., you have to pay) journals from the previous category, (iii) 64 ‘ecology’ journals, (iv) 32 ‘conservation’ journals, (v) 43 ‘sustainability’ journals (with general and energy-focussed journals included), and (vi) 21 ‘marine & freshwater’ journals.

Remember not to take much notice if a journal boasts about how its Impact Factor has increased this year, because these tend to increase over time anyway What’s important is a journal’s relative (to other journals) rank.

Here are the results:

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Categories : conservation, conservation biology, conservation ecology, ecology, marine, research, science, scientific publishing, sustainability

Fallacy of zero-extinction targets

20 05 2022

Nearly a decade ago (my how time flies*), I wrote a post about the guaranteed failure of government policies purporting no-extinction targets within their environmental plans. I was referring to the State of South Australia’s (then) official policy of no future extinctions.

In summary, zero- (or no-) extinction targets at best demonstrate a deep naïvety of how ecology works, and at worst, waste a lot of resources on interventions doomed to fail.

1. Extinctions happen all the time, irrespective of human activity;

2. Through past environmental degradation, we are guaranteed to see future extinctions because of extinction lags;

3. Few, if any, of the indicators of biodiversity change show improvement.

4. Climate change will also guarantee additional (perhaps even most) future extinctions irrespective of Australian policies.

I argued that no-extinction policies are therefore disingenuous to the public in the extreme because they sets false expectations, engender disillusionment after inevitable failure, and ignores the concept of triage — putting our environment-restoration resources toward the species/systems with the best chance of surviving (uniqueness notwithstanding).

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Categories : Australia, biodiversity, climate change, conservation, conservation biology, decline, deforestation, ecological literacy, ecology, ecosystem, environmental policy, environmental science, extinction, extinction debt, management, planning, recovery, reforestation, restoration, science, threatened species, trophic cascades

Bane of the bees

19 04 2022

Bees are essential for pollination, but their critical function can be perturbed by pesticides. The detrimental effects of those chemicals accumulate through a bee’s life, and become stronger if females cannot collect pollen from wildflowers.

Our childhood experiences partly determine our health, personality, and lifestyle when we are adults, and our experiences accumulate over time. Accumulation also occurs in any living being and can explain why some populations and species adapt to their environments better than others.

Migratory birds are a clear example. Thousands can travel to their breeding grounds after wintering elsewhere, and those coming from regions laden with resources (e.g., food, shelter, water) will have a greater reproductive success than those that migrated from resource-poor regions (1). In ecology, these ‘carry-over’ effects can take place between seasons, but also across the different phases of the life cycle of a plant or animal (2).

From larvae to adults

Clara Stuligross and Neal Williams have studied the carry-over effect of pesticides on the blue orchard bee Osmia lignaria in California (3). Instead of the typical hives constructed by the honey bee (Apis mellifera), solitary blue orchard bees make lines of brood cells with mud partitions, glued into holes and crevices of branches and trunks from fallen trees (see videos here, here, & here).

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Categories : agriculture, behaviour, connectivity, conservation, conservation biology, ecology, pollination, research, toxicology, toxification

A cascade of otters

4 04 2022

Carnivores are essential components of trophic webs, and ecosystem functions crumble with their loss. Novel data show the connection between calcareous reefs and sea otters under climate change.

Trophic cascade on the Aleutian Islands (Alaska, USA) linking sea otters (Enhydra lutris) with sea urchins (Strongylocentrotus polyacanthus) and calcareous reefs (Clathromorphum nereostratum). With males weighting up to 50 kg, sea otters have been IUCN-catalogued as Endangered since 2000. The top photo shows a male in a typical, belly-up floating position. The bottom photo shows live (pinkish) and dead (whitish) tissue on the reef surface as a result of grazing of sea urchins at a depth of 10 m. Sea otters are mesopredators, typically foraging on small prey like sea urchins, but their historical decline due to overhunting unleashed the proliferation of the echinoderms. At the same time, acidification and sea-water warming have softened the skeleton of the reefs, allowing for deeper grazing by sea urchins that eliminate the growth layer of living tissue that give the reefs their pinkish hue. Large extents of dead reefs stop fixing the excess in carbonic acid, whose carbon atoms sea water sequesters from the atmosphere enriched in carbon by our burning of fossil fuels. Photos courtesy of Joe Tomoleoni taken in Moss Landing – California, USA (otter), and on the Near Islands – Aleutian Archipelago, Alaska (reef).

For most, the decisions made by people we have never met affect our daily lives. Other species experience the same phenomenon because they are linked to one another through a trophic cascade.

A trophic cascade occurs when a predator limits the abundance or behaviour of its prey, in turn affecting the survival of a third species in lower trophic levels that have nothing directly to do with the predator in question (1).

Sea otters (Enhydra lutris) represent a text-book example of a trophic cascade. These mustelids (see video footage here and here) hunt and control the populations of sea urchins (Strongylocentrotus polyacanthus), hence favouring kelp forests  — the fronds of which are eaten by the sea urchins.

Removing the predator from the equation should lead to more sea urchins and less kelp, and this chain of events is exactly what happened along the coasts of the North Pacific (2, 3). The historical distribution of sea otters once ranged from Japan to Baja California through the Aleutian Islands (see NASA’s photo from space, and documentary on the island of Unimak), a sub-Arctic, arc-shaped archipelago including > 300 islands between Alaska (USA) and the Kamchatka Peninsula (Russia), extending ~ 2000 kilometres, and having a land area of ~ 18,000 km2.

But the fur trade during the 18th and 19th centuries brought the species to the brink of extinction, down to < 2000 surviving individuals (4). Without otters, sea urchins boomed and deforested kelp ecosystems during the 20th Century (5). Now we also know that this trophic cascade has climate-related implications in other parts of the marine ecosystem.

Underwater bites

Doug Rasher and collaborators have studied the phenomenon on the Aleutian Islands (6). The seabed of this archipelago is a mix of sandy beds, kelp forests, and calcareous reefs made up of calcium and magnesium carbonates fixed by the red algae Clathromorphum nereostratum. These reefs have grown at a rate of 3 cm annually for centuries as the fine film of living tissue covering the reef takes the carbonates from the seawater (7).

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Categories : biodiversity, biosequestration, carbon, climate change, community ecology, conservation, conservation biology, decline, ecology, ecosystem function, ecosystem services, environmental policy, environmental science, exploitation, extinction, fisheries, harvest, human-wildlife conflict, investment, kelp, mammal, management, marine, meso-predator release, predation, predator, recovery, threatened species, top-down ecology

The integrity battlefield: where science meets policy

4 03 2022

Professor Ross Thompson, University of Canberra

On the whole, I am inclined to conclude that my experience of academia and publishing my work has been largely benign. Despite having published 120-odd peer-reviewed papers, I can count the number of major disputes on one hand. Where there have been disagreements, they have centred on issues of content, and despite the odd grumble, things have rarely escalated to the ad hominem. I have certainly never experienced concerted attacks on my work.

But that changed recently. I work in water science, participating in and leading multi-disciplinary teams that do research directly relevant to water policy and management. My colleagues and I work closely with state and federal governments and are often funded by them through a variety of mechanisms. Our teams are a complex blend of scientists from universities, state and federal research agencies, and private-sector consultancies. Water is big business in Australia, and its management is particularly pertinent as the world’s driest inhabited continent struggles to come to terms with the impacts of climate change.

In the last 10 years, Australia has undergone a AU$16 billion program of water reform that has highlighted the extreme pressure on ecosystems, rural communities, and water-dependent industries. In 2019, two documentaries (Cash Splash and Pumped) broadcast by the Australian Broadcasting Corporation were highly critical of the  outcomes of water reform. A group of scientists involved in working on the Murray-Darling Basin were concerned enough about the accuracy of aspects of those stories to support Professor Rob Vertessy from the University of Melbourne in drafting an Open Letter in response. I was a co-author on that letter, and something into which I did not enter lightly. We were very concerned about being seen to advocate for any particular policy position, but were simultaneously committed to contributing to an informed public debate. A later investigation by the Australian Communications and Media Authority also highlighted concerns with the Cash Splash documentary.

Fast forward to 2021 and the publication of a paper by Colloff et al. (2021) in the Australasian Journal of Water Resources. In that paper, the authors were critical of the scientists that had contributed to the Open Letter and claimed they had been subject to “administrative capture” and “issue advocacy”. Administrative capture is defined here as:

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Categories : Australia, climate change, drought, ecology, environmental economics, environmental policy, environmental science, ethics, governance, management, modelling, monitoring, Murray River, Murray-Darling, planning, research, River Murray, science, science writing, scientific writing, southern Australia, water

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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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

Extinct megafauna prone to ancient hunger games

14 12 2021

I’m very chuffed today to signal the publication of what I think is one of the most important contributions to the persistent conundrum surrounding the downfall of Australia’s megafauna many tens of millennia ago.

Diprotodon optimum. Artwork by palaeontologist and artist Eleanor (Nellie) Pease (commissioned by the ARC Centre of Excellence for Australian Biodiversity and Heritage)

Sure, I’m obviously biased in that assessment because it’s a paper from our lab and I’m a co-author, but if readers had any inkling of the work that went into this paper, I think they might consider adopting my position. In addition, the injection of some actual ecology into the polemic should be viewed as fresh and exciting.

Having waded into the murky waters of the ‘megafauna debate’ for about a decade now, I’ve become a little sensitive to even a whiff of binary polemic surrounding their disappearance in Australia. Acolytes of the climate-change prophet still beat their drums, screaming for the smoking gun of a spear sticking out of a Diprotodon‘s skull before they even entertain the notion that people might have had something to do with it — but we’ll probably never find one given the antiquity of the event (> 40,000 years ago). On the other side are the blitzkriegers who declaim that human hunting single-handedly wiped out the lot.

Well, as it is for nearly all extinctions, it’s actually much more complicated than that. In the case of Sahul’s megafauna disappearances, both drivers likely contributed, but the degree to which both components played a part depends on where and when you look — Fred Saltré demonstrated that elegantly a few years ago.

Palorchestes. Artwork by palaeontologist and artist Eleanor (Nellie) Pease (commissioned by the ARC Centre of Excellence for Australian Biodiversity and Heritage)

So, why does the polemic persist? In my view, it’s because we have largely depended on the crude comparison of relative dates to draw our conclusions. That is, we look to see if some climate-change proxy shifted in any notable way either before or after an inferred extinction date. If a particular study claims evidence that a shift happened before, then it concludes climate change was the sole driver. If a study presents evidence that a shift happened after, then humans did it. Biases in geochronological inference (e.g., spatial, contamination), incorrect application of climate proxies, poor taxonomic resolution, and not accounting for the Signor-Lipps effect all contribute unnecessarily to the debate because small errors or biases can flip relative chronologies on their head and push conclusions toward uncritical binary outcomes. The ‘debate’ has been almost entirely grounded on this simplistically silly notion.

This all means that the actual ecology has been either ignored or merely made up based on whichever pet notion of the day is being proffered. Sure, there are a few good ecological inferences out there from some damn good modellers and ecologists, but these have all been greatly simplified themselves. This is where our new paper finally takes the ecology part of the problem to the next level.

Led by Global Ecology and CABAH postdoctoral fellow, John Llewelyn, and guided by modelling guru Giovanni Strona at University of Helsinki, the paper Sahul’s megafauna were vulnerable to plant-community changes due to their position in the trophic network has just been published online in Ecography. Co-authors include Kathi Peters, Fred Saltré, and me from Flinders Global Ecology, Matt McDowell and Chris Johnson from UTAS, Daniel Stouffer from University of Canterbury (NZ), and Sara de Visser from University of Groningen (Netherlands).

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Categories : anthropocene, Australia, bottom-up ecology, climate change, climate shift, community ecology, ecology, ecosystem, exploitation, extinction, mammal, mathematics, modelling, palaeo-ecology, predation, predator, South Australia, southern Australia, top-down ecology, trophic cascades, World Heritage Area

Animating models of ecological change

6 12 2021

Flinders University Global Ecology postdoc, Dr Farzin Shabani, recently created this astonishing video not only about the results of his models predicting vegetation change in northern Australia as a function of long-term (tens of thousands of years) climate change, but also on the research journey itself!

He provides a brief background to how and why he took up the challenge:

Science would be a lot harder to digest without succinct and meaningful images, graphs, and tables. So, being able to visualise both inputs and outputs of scientific models to cut through the fog of data is an essential element of all science writing and communication. Diagrams help us understand trends and patterns much more quickly than do raw data, and they assist with making comparisons.

During my academic career, I have studied many different topics, including natural hazards (susceptibility & vulnerability risks), GIS-based ensemble modelling, climate-change impacts, environmental modelling at different temporal and spatial scales, species-distribution modelling, and time-series analysis. I use a wide range of graphs, charts, plots, maps and tables to transfer the key messages.

For my latest project, however, I was given the opportunity to make a short animation and visualise my results and the journey itself. I think that my animation inspires a sense of wonder, which is among the most important goals of science education. I also think that my animation draws connections to real-life problems (e.g., ecosystem changes as a product of climate change), and also develops an appreciation of the scientific process itself.

Take a look at let me know what you think!

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Categories : Australia, bottom-up ecology, climate change, community ecology, ecology, ecosystem, fire, mathematics, modelling, research, science, science communication, science writing, scientific writing, vegetation

And this little piggy went extinct

24 11 2021

Back in June of this year I wrote (whinged) about the disappointment of writing a lot of ecological models that were rarely used to assist real-world wildlife management. However, I did hint that another model I wrote had assistance one government agency with pig management on Kangaroo Island.

Well, now that report has been published online and I’m permitted to talk about it. I’m also very happy to report that, in the words of the Government of South Australia’s Department of Primary Industries and Regions (PIRSA),

Modelling by the Flinders University Global Ecology Laboratory shows the likelihood and feasibility of feral pig eradication under different funding and eradication scenarios. With enough funding, feral pigs could be eradicated from Kangaroo Island in 2 years.

This basically means that because of the model, PIRSA was successful in obtaining enough funding to pretty much ensure that the eradication of feral pigs from Kangaroo Island will be feasible!

Why is this important to get rid of feral pigs? They are a major pest on the Island, causing severe economic and environmental impacts both to farms and native ecosystems. On the agricultural side of things, they prey on newborn lambs, eat crops, and compete with livestock for pasture. Feral pigs damage natural habitats by up-rooting vegetation and fouling waterholes. They can also spread weeds and damage infrastructure, as well as act as hosts of parasites and diseases (e.g., leptospirosis, tuberculosis, foot-and-mouth disease) that pose serious threats to industry, wildlife, and even humans.

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Categories : agriculture, alien species, Australia, conservation, demography, disease, ecology, environmental policy, harvest, invasive species, investment, management, mathematics, modelling, pig, predator, research, restoration

Avoiding a ghastly future — The Science Show

1 10 2021

Just thought I’d share the audio of an interview I did with the famous Robyn Williams of ABC Radio National‘s The Science Show.

I’d be surprised if any Australians with even a passing interest in science could claim not to have listened to the Science Show before, and I suspect a fair mob of people overseas would be in the same boat.

It was a real privilege to talk with Robyn about our work on the ghastly future, and as always, the production value is outstanding.

Thank you, Robyn and the ABC.

Listen below, or link to the interview directly.


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Categories : biodiversity, carbon, climate change, conservation, corruption, decline, deforestation, ecology, economics, ecosystem services, environmental economics, environmental policy, environmental science, extinction, food, governance, human overpopulation, impact, investment, journalism, management, media, pollution, research, science, science communication, science writing, sustainability, threatened species

It’s a tough time for young conservation scientists

24 08 2021

Sure, it’s a tough time for everyone, isn’t it? But it’s a lot worse for the already disadvantaged, and it’s only going to go downhill from here. I suppose that most people who read this blog can certainly think of myriad ways they are, in fact, still privileged and very fortunate (I know that I am).

Nonetheless, quite a few of us I suspect are rather ground down by the onslaught of bad news, some of which I’ve been responsible for perpetuating myself. Add lock downs, dwindling job security, and the prospect of dying tragically due to lung infection, many have become exasperated.

I once wrote that being a conservation scientist is a particularly depressing job, because in our case, knowledge is a source of despair. But as I’ve shifted my focus from ‘preventing disaster’ to trying to lessen the degree of future shittyness, I find it easier to get out of bed in the morning.

What can we do in addition to shifting our focus to making the future a little less shitty than it could otherwise be? I have a few tips that you might find useful:

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Categories : Australia, biodiversity, climate change, conservation, conservation biology, conservation ecology, decline, deforestation, disease, ecology, economics, education, environmental economics, environmental policy, environmental science, extinction, fire, flood, governance, habitat loss, health, human overpopulation, invasive species, management, mathematics, modelling, poverty, prioritisation, research, science, sustainability, threatened species

Pest plants and animals cost Australia around $25 billion a year — and it will get worse

2 08 2021
AAP

Corey J. A. Bradshaw, Flinders University and Andrew Hoskins, CSIRO

This article is republished from The Conversation under a Creative Commons licence. Read the original article.

Shamefully, Australia has one of the highest extinction rates in the world.
And the number one threat to our species is invasive or “alien” plants and animals.

But invasive species don’t just cause extinctions and biodiversity loss – they also create a serious economic burden. Our research, published today, reveals invasive species have cost the Australian economy at least A$390 billion in the last 60 years alone.

Our paper – the most detailed assessment of its type ever published in this country – also reveals feral cats are the worst invasive species in terms of total costs, followed by rabbits and fire ants.

Without urgent action, Australia will continue to lose billions of dollars every year on invasive species.

Feral cats are Australia’s costliest invasive species. Source: Adobe Stock/240188862

Huge economic burden

Invasive species are those not native to a particular ecosystem. They are introduced either by accident or on purpose and become pests.

Some costs involve direct damage to agriculture, such as insects or fungi destroying fruit. Other examples include measures to control invasive species like feral cats and cane toads, such as paying field staff and buying fuel, ammunition, traps and poisons.

Our previous research put the global cost of invasive species at A$1.7 trillion. But this is most certainly a gross underestimate because so many data are missing.

Read more:
Attack of the alien invaders: pest plants and animals leave a frightening $1.7 trillion bill

As a wealthy nation, Australia has accumulated more reliable cost data than most other regions. These costs have increased exponentially over time – up to sixfold each decade since the 1970s.

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Categories : agriculture, alien species, Australia, biodiversity, buffalo, climate change, conservation, conservation biology, dingo, disease, ecology, economics, ecosystem, ecosystem function, ecosystem services, environmental economics, environmental policy, extinction, Flinders University, health, human-wildlife conflict, impact, invasive species, kangaroo, mammal, management, monitoring, predator

Journal ranks 2020

23 07 2021

This is the 13th year in a row that I’ve generated journal ranks based on the journal-ranking method we published several years ago.

There are few differences in how I calculated this year’s ranks, as well as some relevant updates:

  1. As always, I’ve added a few new journals (either those who have only recently been scored with the component metrics, or ones I’ve just missed before);
  2. I’ve included the new ‘Journal Citation Indicator’ (JCI) in addition to the Journal Impact Factor and Immediacy Index from Clarivate ISI. JCI “… a field-normalised metric, represents the average category-normalised citation impact for papers published in the prior three-year period.”. In other words, it’s supposed to correct for field-specific citation trends;
  3. While this isn’t my change, the Clarivate metrics are now calculated based on when an article is first published online, rather than just in an issue. You would have thought that this should have been the case for many years, but they’ve only just done it;
  4. I’ve also added the ‘CiteScore’ (CS) in addition to the Source-Normalised Impact Per Paper (SNIP) and SCImago Journal Rank (SJR) from Scopus. CS is “the number of citations, received in that year and previous 3 years, for documents published in the journal during that period (four years), divided by the total number of published documents … in the journal during the same four-year period”;
  5. Finally, you can access the raw data for 2020 (I’ve done the hard work for you) and use my RShiny app to derive your own samples of journal ranks (also see the relevant blog post). You can add new journal as well to the list if my sample isn’t comprehensive enough for you.

Since the Google Scholar metrics were just released today, I present the new 2020 ranks for: (i) 101 ecology, conservation and multidisciplinary journals, and a subset of (ii) 61 ‘ecology’ journals, (iii) 29 ‘conservation’ journals, (iv) 41 ‘sustainability’ journals (with general and energy-focussed journals included), and (v) 20 ‘marine & freshwater’ journals.

One final observation. I’ve noted that several journals are boasting about how their Impact Factors have increased this year, when they fail to mention that this is the norm across most journals. As you’ll see below, relative ranks don’t actually change that much for most journals. In fact, this is a redacted email I received from a journal that I will not identify here:

We’re pleased to let you know that the new Impact Factor for [JOURNAL NAME] marks a remarkable increase, as it now stands at X.XXX, compared to last year’s X.XXX. And what is even more important: [JOURNAL NAME] increased its rank in the relevant disciplines: [DISCIPLINE NAME].

Although the Impact Factor may not be the perfect indicator of success, it remains the most widely recognised one at journal level. Therefore, we’re excited to share this achievement with you, as it wouldn’t have been possible, had it not been for all of your contributions and support as authors, reviewers, editors and readers. A huge ‘THANK YOU’ goes to all of you!

What bullshit.

Anyway, on to the results:

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Categories : conservation, conservation biology, conservation ecology, ecology, marine, research, science, scientific publishing, sustainability

Losing half of tropical fish species as corals disappear

30 06 2021

When snorkelling in a reef, it’s natural to think of coral colonies as a colourful scenography where fish act in a play. But what would happen to the fish if the stage went suddenly empty, as in Peter Brook’s 1971 Midsummer Night’s Dream? Would the fish still be there acting their roles without a backdrop?

This question is not novel in coral-reef science. Ecologists have often compared reef fish diversity and biomass in selected localities before and after severe events of coral mortality. Even a temporary disappearance of corals might have substantial effects on fish communities, sometimes resulting in a local disappearance of more than half of local fish species.

Considering the multiple, complex ways fish interact with — and depend on — corals, this might appear as an obvious outcome. Still, such complexity of interactions makes it difficult to predict how the loss of corals might affect fish diversity in specific contexts, let alone at the global scale.

Focusing on species-specific fish-coral associations reveals an inconsistent picture with local-scale empirical observations. When looking at the fraction of local fish diversity that strictly depends on corals for food and other more generic habitat requirements (such as shelter and reproduction), the global picture suggests that most fish diversity in reef locality might persist in the absence of corals. 

The mismatch between this result and the empirical evidence of a stronger coral dependence suggests the existence of many hidden ecological paths connecting fish to corals, and that those paths might entrap many fish species for which the association to corals is not apparent.

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Categories : biodiversity, bottom-up ecology, climate change, conservation, coral reefs, decline, ecology, extinction, extinction debt, fish, function, habitat loss, marine, research, top-down ecology, trophic cascades

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