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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

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

17 12 2022

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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Tags: biodiversity, climate change, conservation, deforestation, ecology, environment, extinction, Global warming
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

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 18^th and 19^th 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 20^th 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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Tags: Alaska, cascade, fisheries, kelp, mesopredator release, otter, Pacific Ocean, sea otter, sea urchins, Trophic cascade, urchins
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

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

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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Tags: Australia, co-extinctions, coextinctions, ecological networks, ecology, extinction, extinction cascade, food web, Giovanni Strona, John Llewelyn, Late Pleistocene, megafauna, Naracoorte, Naracoorte Caves, palaeoecology, Sahul, Trophic cascade, trophic web
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

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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Tags: climate change, coral reefs, corals, extinction, Global warming, reef fish
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

South Australia is still killing dingoes

14 04 2020

As we did for Victoria, here’s our submission to South Australia’s proposed changes to its ‘wild dog’ and dingo policy (organised again by the relentless and venerable Dr Kylie Cairns):

14 April 2020

The Honourable Tim Whetstone MP, Minister for Primary Industries and Regional Development, South Australia

cc: The Honourable David Speirs MP, Minister for Environment and Water, South Australia
cc: Primary Industries and Regions South Australia
cc: Dr Bradley Page, PIRSA Wild Dog Program

RE: PROPOSED CHANGES TO THE SA WILD DOG AND DINGO POLICY

Dear Minister,

The undersigned welcome the opportunity to comment on the proposed changes to the South Australian (SA) Government’s ‘Wild dog and Dingo’ declared animal policy under section 10 (1)(b) of the Natural Resources Management Act 2004. The proposed changes raise serious concerns for dingoes in SA because it:

1. Requires all landholders to follow minimum baiting standards, including organic producers or those not experiencing stock predation.

Requires dingoes within Ngarkat Conservation Park (Region 4) to be destroyed, with ground baiting to occur every 3 months.
Requires ground baiting on land irrespective of whether stock predation is occurring or not, or evidence of dingo (wild dog) presence.

2. Allows aerial baiting of dingoes (aka wild dogs) in all NRM regions – including within National Parks.

3. Uses inappropriate and misleading language to label dingoes as “wild dogs”

We strongly urge the PIRSA to reject the proposed amendments to the SA wild dog and dingo policy. Instead the PIRSA should seek consultation with scientific experts in ecology, biodiversity and wildlife-conflict to develop a policy which considers the important ecological and cultural identity of the dingo whilst seeking to minimise their impact on livestock using best-practice and evidence-based guidelines. Key to this aim, livestock producers should be assisted with the help of PIRSA to seek alternative stock protection methodology and avoid lethal control wherever possible. On the balance of scientific evidence, protection of dingoes should be enhanced rather than diminished. Widespread aerial baiting programs are not compatible with the continued persistence of genetically intact and distinct dingoes in SA.

In this context, we strongly emphasise the following points: Read the rest of this entry »

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Tags: 1080, control, dingo, environmental policy, poison, predator, shooting, South Australia, wild dog
Categories : Australia, biodiversity, cat, community ecology, conservation, dingo, ecosystem function, ecosystem services, environmental policy, ethics, exploitation, fox, function, genetics, harvest, human-wildlife conflict, invasive species, kangaroo, mammal, management, meso-predator release, predation, predator, recovery, science, South Australia, sustainability, threatened species, top-down ecology

Did people or climate kill off the megafauna? Actually, it was both

10 12 2019

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

—

Earth is now firmly in the grips of its sixth “mass extinction event”, and it’s mainly our fault. But the modern era is definitely not the first time humans have been implicated in the extinction of a wide range of species.

In fact, starting about 60,000 years ago, many of the world’s largest animals disappeared forever. These “megafauna” were first lost in Sahul, the supercontinent formed by Australia and New Guinea during periods of low sea level.

The causes of these extinctions have been debated for decades. Possible culprits include climate change, hunting or habitat modification by the ancestors of Aboriginal people, or a combination of the two.

The main way to investigate this question is to build timelines of major events: when species went extinct, when people arrived, and when the climate changed. This approach relies on using dated fossils from extinct species to estimate when they went extinct, and archaeological evidence to determine when people arrived.

Comparing these timelines allows us to deduce the likely windows of coexistence between megafauna and people.

We can also compare this window of coexistence to long-term models of climate variation, to see whether the extinctions coincided with or shortly followed abrupt climate shifts.

Data drought

One problem with this approach is the scarcity of reliable data due to the extreme rarity of a dead animal being fossilised, and the low probability of archaeological evidence being preserved in Australia’s harsh conditions. Read the rest of this entry »

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Tags: archaeology, climate change, extinction, megafauna, palaeoecology, palaeontology, Sahul
Categories : Australia, biodiversity, climate change, climate shift, conservation, decline, exploitation, extinction, mathematics, modelling, palaeo-ecology, southern Australia, synergies, top-down ecology, water

Climate change and humans together pushed Australia’s biggest beasts to extinction

25 11 2019

people-megafauna Over the last 60,000 years, many of the world’s largest species disappeared forever. Some of the largest that we generally call ‘megafauna’ were first lost in Sahul — the super-continent formed by the connection of Australia and New Guinea during periods of low sea level. The causes of these extinctions have been heavily debated for decades within the scientific community.

Three potential drivers of these extinctions have been suggested. The first is climate change that assumes an increase in arid conditions that eventually became lethal to megafauna. The second proposed mechanism is that the early ancestors of Aboriginal people who either hunted megafauna species to extinction, or modified ecosystems to put the largest species at a disadvantage. The third and most nuanced proposed driver of extinction is the combination of the first two.

The primary scientific tools we scientists use to determine which of these proposed causes of extinction have the most support are dated fossil records from the extinct species themselves, as well as archaeological evidence from early Aboriginal people. Traditionally, the main way we use these data is to construct a timeline of when the last fossil of a species was preserved, and compare this to evidence indicating when people arrived. We can also reconstruct climate patterns back tens of thousands of years using models similar to the ones used today to predict future climates. Based on the comparison of all of these different timelines, we conclude that abrupt climate changes in the past were influential if they occurred at or immediately before a recorded extinction event. On the other hand, if megafauna extinctions occur immediately after humans are thought to have arrived, we attribute more weight to human arrival as a driver.

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Tags: archaeology, Australia, chronology, climate change, extinction, humans, Late Pleistocene, megafauna, palaeoecology, palaeontology, Pleistocene, Sahul, south-eastern Australia, spatial statistics
Categories : Australia, climate change, climate shift, conservation, ecology, extinction, palaeo-ecology, southern Australia, statistics, top-down ecology

Victoria, please don’t aerial-bait dingoes

10 10 2019

Here’s a submission to Victoria’s proposed renewal of special permission from the Commonwealth to poison dingoes:

dingo with bait

08 October 2019

Honourable Lily D’Ambrosio MP

Minister for Energy, Environment and Climate Change
Level 16, 8 Nicholson Street, East Melbourne, VIC 3002

lily.dambrosio@parliament.vic.gov.au

cc:

The Hon Jaclyn Symes, Minister for Agriculture, Victoria

(jaclyn.symes@parliament.vic.gov.au)

Dr Sally Box, Threatened Species Commissioner

(ThreatenedSpeciesCommissioner@environment.gov.au)

The Hon Sussan Ley MP, Minister for Environment, Australia

(Farrer@aph.gov.au)

RE: RENEWAL OF AERIAL BAITING EXEMPTION IN VICTORIA FOR WILD DOG CONTROL USING 1080

Dear Minister,

The undersigned welcome the opportunity to comment on the proposed renewal of special permission from the Commonwealth under Sections 18 and 18A of the Environment Protection and Biodiversity Conservation Act 1999 (Commonwealth) to undertake aerial 1080 baiting in six Victorian locations for the management of ‘wild dogs’. This raises serious concerns for two species listed as threatened and protected in Victoria: (1) dingoes and (2) spot-tailed quolls (Dasyurus maculatus).

First, we must clarify that the terminology ‘wild dog’ is not appropriate when discussing wild canids in Australia. One of the main discussion points at the recent Royal Zoological Society of NSW symposium ‘Dingo Dilemma: Cull, Contain or Conserve’ was that the continued use of the terminology ‘wild dog’ is not justified because wild canids in Australia are predominantly dingoes and dingo hybrids, and not, in fact, feral domestic dogs. In Victoria, Stephens et al. (2015) observed that only 5 out of 623 wild canids (0.008%) sampled were feral domestic dogs with no evidence of dingo ancestry. This same study determined that 17.2% of wild canids in Victoria were pure or likely pure dingoes and 64.4% were hybrids with greater than 60% dingo ancestry. Additionally, comparative studies by Jones (1988, 1990 and 2009) observed that dingoes maintained a strong phenotypic identity in the Victorian highlands over time, and perceptively ‘wild dog’ like animals were more dingo than domestic dog.

As prominent researchers in predator ecology, biology, archaeology, cultural heritage, social science, humanities, animal behaviour and genetics, we emphasise the importance of dingoes in Australian, and particularly Victorian, ecosystems. Dingoes are the sole non-human, land-based, top predator on the Australian mainland. Their importance to the ecological health and resilience of Australian ecosystems cannot be overstated, from regulating wild herbivore abundance (e.g., various kangaroo species), to reducing the impacts of feral mesopredators (cats, foxes) on native marsupials (Johnson & VanDerWal 2009; Wallach et al. 2010; Letnic et al. 2012, 2013; Newsome et al. 2015; Morris & Letnic 2017). Their iconic status is important to First Nations people and to the cultural heritage of all Australians. Read the rest of this entry »

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Tags: 1080, 1080 poison, cat, dingo, environment, environmental policy, fox, policy, quoll, Victoria
Categories : alien species, Australia, biodiversity, cat, community ecology, conservation, decline, demography, dingo, ecology, ecosystem, ecosystem function, environmental policy, extinction, fox, genetics, harvest, human-wildlife conflict, introgression, invasive species, mammal, management, meso-predator release, predation, predator, science, southern Australia, threatened species, top-down ecology, trophic cascades

“Overabundant” wildlife usually isn’t

12 07 2019

koalacrosshairs Late last year (10 December) I was invited to front up to the ‘Overabundant and Pest Species Inquiry’ at the South Australian Parliament to give evidence regarding so-called ‘overabundant’ and ‘pest’ species.

There were the usual five to six Ministers and various aides on the Natural Resources Committee (warning here: the SA Parliament website is one of the most confusing, archaic, badly organised, and generally shitty government sites I’ve yet to visit, so things require a bit of nuanced searching) to whom I addressed on issues ranging from kangaroos, to dingoes, to koalas, to corellas. The other submissions I listened to that day were (mostly) in favour of not taking drastic measures for most of the human-wildlife conflicts that were being investigated.

Forward seven months and the Natural Resources Committee has been reported to have requested the SA Minister for Environment to allow mass culling of any species (wildlife or feral) that they deem to be ‘overabundant’ or a ‘pest’.

So, the first problem is terminological in nature. If you try to wade through the subjectivity, bullshit, vested interests, and general ignorance, you’ll quickly realise that there is no working definition or accepted meaning for the words ‘overabundant’ or ‘pest’ in any legislation. Basically, it comes down to a handful of lobbyists and other squeaky wheels defining anything they deem to be a nuisance as ‘overabundant’, irrespective of its threat status, ecological role, or purported impacts. It is, therefore, entirely subjective, and boils down to this: “If I don’t like it, it’s an overabundant pest”. Read the rest of this entry »

Comments : 2 Comments »
Tags: dingo, environment, fur seals, Government of South Australia, Kangaroo, koala, little corella, Natural Resources Committee, South Australia
Categories : alien species, animal welfare, Australia, biodiversity, climate change, community ecology, conservation, decline, dingo, ecology, ecosystem, ecosystem function, environmental policy, exploitation, fish, fisheries, harvest, human-wildlife conflict, impact, invasive species, kangaroo, management, meso-predator release, predation, predator, science, South Australia, sustainability, threatened species, top-down ecology

Fancy a job in biosecurity controlling pest species?

13 12 2018

Rabbits-Western-NSW

My mate Dr Brad Page — Principal Biosecurity Officer (Pest Animals) at Biosecurity SA — asked me to post the following jobs he’s advertising for pest-animal control. Now, I’m near-completely opposed to ‘wild dog’ (i.e., dingo) control in Australia, but I’ve agreed to post the third position as well, despite my ecological misgivings. Brad has a different perspective.

—

We have exciting opportunities for three new pest animal control coordinators, who will be working to support and reinvigorate control of deer, rabbits, and ‘wild dogs’.

All three coordinators will be part of our Biosecurity SA Division within PIRSA. These new positions will report to our Principal Biosecurity Officer, Pest Animals.

Deer and Rabbit Control Coordinators (two positions)

The Deer Control Coordinator and the Rabbit Control Coordinator will provide tailored professional support to natural resource management (NRM) staff and community groups doing control programs. These coordinators will aim to increase the impact of deer and rabbit control programs to support primary producers and biodiversity managers. The position will connect and empower existing community and industry groups, maximising impacts of their efforts to control feral deer and rabbits in agricultural landscapes. Read the rest of this entry »

Comments : 1 Comment »
Tags: Australia, biosecurity, deer, dingoes, employment, feral deer, job advertisement, jobs, pest species, PIRSA, rabbits, state government, wild dogs
Categories : agriculture, alien species, animal welfare, Australia, environmental policy, governance, human-wildlife conflict, invasive species, jobs, mammal, management, meso-predator release, restoration, South Australia, southern Australia, top-down ecology

Global warming causes the worst kind of extinction domino effect

25 11 2018

Dominos_Rough1-500x303 Just under two weeks ago, Giovanni Strona and I published a paper in Scientific Reports on measuring the co-extinction effect from climate change. What we found even made me — an acknowledged pessimist — stumble in shock and incredulity.

But a bit of back story is necessary before I launch into describing what we discovered.

Last year, some Oxbridge astrophysicists (David Sloan and colleagues) published a rather sensational paper in Scientific Reports claiming that life on Earth would likely survive in the face of cataclysmic astrophysical events, such as asteroid impacts, supernovae, or gamma-ray bursts. This rather extraordinary conclusion was based primarily on the remarkable physiological adaptations and tolerances to extreme conditions displayed by tardigrades¹— those gloriously cute, but tiny (most are around 0.5 mm long as adults) ‘water bears’ or ‘moss piglets’ — could you get any cuter names?

aHR0cDovL3d3dy5saXZlc2NpZW5jZS5jb20vaW1hZ2VzL2kvMDAwLzA5OC81NzMvb3JpZ2luYWwvc3dpbW1pbmctdGFyZGlncmFkZS5qcGc=

Found almost everywhere and always (the first fossils of them date back to the early Cambrian over half a billion years ago), these wonderful little creatures are some of the toughest metazoans (multicellular animals) on the planet. Only a few types of extremophile bacteria are tougher.

So, boil, fry or freeze the Earth, and you’ll still have tardigrades around, concluded Sloan and colleagues.

When Giovanni first read this, and then passed the paper along to me for comment, our knee-jerk reaction as ecologists was a resounding ‘bullshit!’. Even neophyte ecologists know intuitively that because species are all interconnected in vast networks linked by trophic (who eats whom), competitive, and other ecological functions (known collectively as ‘multiplex networks’), they cannot be singled out using mere thermal tolerances to predict the probability of annihilation. Read the rest of this entry »

Comments : 9 Comments »
Tags: annihilation, catastrophe, climate change, co-extinctions, community ecology, Complex systems, ecological networks, extinction, extinction cascades, Global warming, modelling, network theory, nuclear winter, tardigrades, virtual Earth
Categories : bottom-up ecology, climate change, climate shift, community ecology, conservation, conservation ecology, ecology, extinction, extinction debt, extinction vortex, modelling, top-down ecology

Save a jaguar by eating less meat

8 10 2018

My encounter with Kaayana in Kaa-Iya National Park in the Bolivian Chaco. Her cub was around but cannot be seen in the photo

I was trapped. Or so I thought.

The jaguar came towards me on the dirt road, calmly but attentively in the dusky light, her nearly full grown cub behind her. Nervous and with only a torch as defence, I held the light high above my head as she approached, trying to look taller. But she was merely curious; and, after 20 minutes, they left. I walked home in the thickening darkness, amazed at having come so close to South America’s top predator. We later named this mother jaguar ‘Kaayana’, because she lives inside Kaa-Iya National Park in the Bolivian Chaco. My fascination with jaguars has only grown since then, but the chances of encountering this incredible animal in the wild have shrunk even since that night.

A few years after that encounter, I’m back to study jaguars in the same forest, only now at the scale of the whole South American Gran Chaco. Jaguars are the third largest cats in the world and the top predators across Latin America. This means that they are essential for keeping ecosystems healthy. However, they are disappearing rapidly in parts of their range.

Understanding how and where the jaguar’s main threats — habitat destruction and hunting — affect them is fundamental to set appropriate strategies to save them. These threats are not only damaging on their own, but they sometimes act simultaneously in an area, potentially having impacts that are larger than their simple sum. For instance, a new road doesn’t only promote deforestation, it also increases hunters’ ability to get into previously inaccessible forests. Similarly, when the forest is cut for cattle ranching, ranchers often kill jaguars for fears of stock loss.

Kaayana was seen years later by Daniel Alarcón, who took much better photos of her and her new cubs

However, the interactions between these threats are still not fully understood. In our new study, just published in the journal Diversity and Distributions, we developed a new framework to quantify how and where habitat destruction and hunting risk acted together over three decades, at the expense of highly suitable jaguar habitat in the Gran Chaco. We also analyzed how well the different Chaco countries — Bolivia, Paraguay and Argentina — and their protected areas maintained key jaguar habitat. Read the rest of this entry »

Comments : 2 Comments »
Tags: Argentina, big cats, Bolivia, Chaco, Felidae, Gran Chaco, habitat loss, human-wildlife conflict, jaguar, Panthera onca, Paraguay, poaching, predators
Categories : agriculture, Amazon, biodiversity, biogeography, cat, conservation, conservation biology, decline, deforestation, development, environmental policy, exploitation, food, habitat loss, harvest, human-wildlife conflict, livestock, mammal, management, poaching, predation, predator, protected area, research, South America, top-down ecology

Minister, why is the dingo no longer ‘fauna’?

7 09 2018

dead dingo So, a few of us have just submitted a letter contesting the Western Australia Government’s recent decision to delist dingoes as ‘fauna’ (I know — what the hell else could they be?). The letter was organised brilliantly by Dr Kylie Cairns (University of New South Wales), and she and the rest of the signatories have agreed to reproduce the letter in full here on ConservationBytes.com. If you feel so compelled, please voice your distaste of this decision officially by contacting the Minister (details below).

CJA Bradshaw

Honourable Stephen Dawson MLC
Minister for Environment; Disability Services
Address: 12^th Floor, Dumas House
2 Havelock Street, WEST PERTH WA 6005
(minister.dawson@dpc.wa.gov.au)

cc: Department of Biodiversity, Conservation and Attractions (biodiversity@dbca.wa.gov.au)
cc: Brendan Dooley (brendan.dooley@dpc.wa.gov.au)

Dear Minister,

The undersigned welcome the opportunity to comment on and recommend alteration of the proposed section (9)(2) order of the Biodiversity Conservation Act 2016 (BC Act) that changes the listing of the dingo from “fauna” to “non-fauna” in Western Australia. Removing the “fauna” status from dingoes has serious consequences for the management and conservation of this species and other native biota it benefits. Currently, dingoes are classed as A7, or fauna that requires a management policy. The proposed section (9)(2) order will move dingoes (as “non-fauna”) to the A5 class, meaning that dingoes must be (lethally) controlled and there will be no obligation for the Department of Biodiversity, Conservation and Attractions to have an appropriate management policy (or approval).

Currently, under the Wildlife Conservation Act 1950 (WC Act) the dingo is considered “unprotected” fauna allowing management under a Department of Biodiversity, Conservation and Attractions management policy. A section (9)(2) order demoting dingoes to “non-fauna” will remove the need for Department of Biodiversity, Conservation and Attractions management policy and instead mandate the lethal control of dingoes throughout Western Australia.

As prominent researchers in top predator ecology, biology, cultural value and genetics, we emphasise the importance of dingoes within Australian, and particularly Western Australia’s ecosystems. Dingoes are indisputably native based on the legislative definition of “any animal present in Australia prior to 1400 AD” from the BC Act. Dingoes have been present in Australia for at least 5000 years. On the Australian mainland they are now the sole non-human land-based top predator. Their importance to the ecological health and resilience of Australian ecosystems cannot be overstated. Read the rest of this entry »

Comments : 4 Comments »
Tags: Australia, Biodiversity Conservation Act 2016, Canis dingo, Department of Biodiversity Conservation and Attractions, dingo, environmental policy, human-wildlife conflict, mesopredator release, Minister for Environment, predator, Stephen Dawson, Western Australia, Wildlife Conservation Act 1950
Categories : Australia, biodiversity, cat, conservation, conservation biology, dingo, ecology, ecosystem function, endemic, environmental policy, exploitation, genetics, human-wildlife conflict, introgression, kangaroo, livestock, mammal, management, meso-predator release, predation, predator, research, science, top-down ecology

Two new postdoctoral positions in ecological network & vegetation modelling announced

21 07 2017

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With the official start of the new ARC Centre of Excellence for Australian Biodiversity and Heritage (CABAH) in July, I am pleased to announce two new CABAH-funded postdoctoral positions (a.k.a. Research Associates) in my global ecology lab at Flinders University in Adelaide (Flinders Modelling Node).

One of these positions is a little different, and represents something of an experiment. The Research Associate in Palaeo-Vegetation Modelling is being restricted to women candidates; in other words, we’re only accepting applications from women for this one. In a quest to improve the gender balance in my lab and in universities in general, this is a step in the right direction.

The project itself is not overly prescribed, but we would like something along the following lines of inquiry: Read the rest of this entry »

Comments : 2 Comments »
Tags: CABAH, Centre of Excellence for Australian Biodiversity and Heritage, ecological networks, employment, Flinders University, gender, gender balance, job, jobs, mathematics, modelling, models, postdoctoral fellowship, STEM, vegetation, women in stem, women-only
Categories : Australia, biodiversity, biogeography, bottom-up ecology, climate change, community ecology, conservation, ecology, ecosystem, ecosystem function, extinction, extinction debt, Flinders University, function, genetics, harvest, jobs, mathematics, meso-predator release, minimum viable population, modelling, palaeo-ecology, population dynamics, population viability analysis, predation, predator, top-down ecology

Palaeo-ecology PhD scholarships

1 03 2017

With my new position as Matthew Flinders Fellow in Global Ecology at Flinders University, I am in the agreeable position to be able to offer two PhD scholarships to the best candidates from around the world. If you feel that you’re up to the challenge, I look forward to hearing from you.

These projects will be in the following palaeo-ecology topics:

PhD Project #1. Ecological networks to examine community cascades of Late Quaternary megafauna extinctions Read the rest of this entry »

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Tags: applications, PhD, PhD scholarships, scholarships, Students
Categories : bottom-up ecology, community ecology, conservation, ecology, Flinders University, metapopulation, niche model, palaeo-ecology, population dynamics, top-down ecology

What makes all that biodiversity possible?

23 09 2015

Predators.

You can either stop reading now because that’s the answer to the question, or you can continue and find out a little more detail.

I’ve just had an extremely pleasant experience reading John Terborgh‘s latest Perspective in PNAS. You know the kind of paper you read that (a) makes you feel smart, (b) confirms what you already think, yet informs you nonetheless, and (c) doesn’t take three days to digest? That’s one of those.

Toward a trophic theory of species diversity is not only all of those things, it’s also bloody well-written and comes at the question of ‘Why are there so many species on the planet when ecological theory can’t seem to explain how?’ with elegance, style and a lifetime of experience. I just might have to update my essential-ecology-papers list. If I had to introduce someone to 60 years of ecological theory on biodiversity, there’s no better place to start.

Read the rest of this entry »