It’s not all about cats

20 10 2014

Snake+OilIf you follow any of the environment news in Australia, you will most certainly have seen a lot about feral cats in the last few weeks. I’ve come across dozens of articles in the last week alone talking about the horrendous toll feral cats have had on Australian wildlife since European arrival. In principle, this is a good thing because finally Australians are groggily waking to the fact that our house moggies and their descendants have royally buggered our biodiversity. As a result, we have the highest mammal extinction rate of any country.

But I argue that the newfound enthusiasm for killing anything feline is being peddled mainly as a distraction from bigger environmental issues and to camouflage the complete incompetence of the current government and their all-out war on the environment.

Call me cynical, but when I read headlines like “Australia aims to end extinction of native wildlife by 2020” and Environment Minister Hunt’s recent speech that he has “… set a goal of ending the loss of mammal species by 2020“, I get more than just a little sick to the stomach.

What a preposterous load of shite. Moreover, what a blatant wool-pulling-over-the-eyes public stunt. Read the rest of this entry »





Putting the ‘science’ in citizen science

30 04 2014
How to tell if a koala has been in your garden. © Great Koala Count

How to tell if a koala has been in your garden. © Great Koala Count

When I was in Finland last year, I had the pleasure of meeting Tomas Roslin and hearing him describe his Finland-wide citizen-science project on dung beetles. What impressed me most was that it completely flipped my general opinion about citizen science and showed me that the process can be useful.

I’m not trying to sound arrogant or scientifically elitist here – I’m merely stating that it was my opinion that most citizen-science endeavours fail to provide truly novel, useful and rigorous data for scientific hypothesis testing. Well, I must admit that I still believe that ‘most’ citizen-science data meet that description (although there are exceptions – see here for an example), but Tomas’ success showed me just how good they can be.

So what’s the problem with citizen science? Nothing, in principle; in fact, it’s a great idea. Convince keen amateur naturalists over a wide area to observe (as objectively) as possible some ecological phenomenon or function, record the data, and submit it to a scientist to test some brilliant hypothesis. If it works, chances are the data are of much broader coverage and more intensively sampled than could ever be done (or afforded) by a single scientific team alone. So why don’t we do this all the time?

If you’re a scientist, I don’t need to tell you how difficult it is to design a good experimental sampling regime, how even more difficult it is to ensure objectivity and precision when sampling, and the fastidiousness with which the data must be recorded and organised digitally for final analysis. And that’s just for trained scientists! Imagine an army of well-intentioned, but largely inexperienced samplers, you can quickly visualise how the errors might accumulate exponentially in a dataset so that it eventually becomes too unreliable for any real scientific application.

So for these reasons, I’ve been largely reluctant to engage with large-scale citizen-science endeavours. However, I’m proud to say that I have now published my first paper based entirely on citizen science data! Call me a hypocrite (or a slow learner). Read the rest of this entry »





South Australia’s tattered environmental remains

16 04 2014
State budget percentage expenditures for health, education and environment

South Australia State budget percentage expenditures for health, education and environment

Yesterday I gave the second keynote address at the South Australia Natural Resource Management (NRM) Science Conference at the University of Adelaide (see also a brief synopsis of Day 1 here). Unfortunately, I’m missing today’s talks because of an acute case of man cold, but at least I can stay at home and work while sipping cups of hot tea.

Many people came up afterwards and congratulated me for “being brave enough to tell the truth”, which both encouraged and distressed me – I am encouraged by the positive feedback, but distressed by the lack of action on the part of our natural resource management leaders.

The simple truth is that South Australia’s biodiversity and ecosystems are in shambles, yet few seem to appreciate this.

So for the benefit of those who couldn’t attend, I’ve uploaded the podcast of my slideshow for general viewing here. I’ve also highlighted some key points from the talk below: Read the rest of this entry »





Essential role of carnivores on the wane

10 01 2014
© Luca Galuzzi www.galuzzi.it

© Luca Galuzzi http://www.galuzzi.it

This interesting review has just come out in Science, and because I was given a heads-up about it, I decided to do a F1000 recommendation. That’s more or less what follows, with some additional thoughts.

Ripple and colleagues can perhaps be excused for stating what might appear to many ‘in the biz’ to be blatantly obvious, but their in-depth review of the status of the world’s carnivores is a comprehensive overview of this essential guild’s worldwide plight. It not only represents an excellent teaching tool, the review elegantly summarises the current status of these essential ecosystem engineers.

The world’s 245 terrestrial carnivores might seem to be ecologically redundant to the informed given their natural rarity, low densities and cryptic behaviour, but nothing could be farther from the truth. Ecologists have only within the last decade or so revealed the essential ecosystem functions of these species (see former posts on CB.com here, here and here). The review focuses on the largest and most well-studied species, but the trends likely apply across most of the order. Read the rest of this entry »





Too small to avoid catastrophic biodiversity meltdown

27 09 2013
Chiew Larn

Chiew Larn Reservoir is surrounded by Khlong Saeng Wildlife Sanctuary and Khao Sok National Park, which together make up part of the largest block of rainforest habitat in southern Thailand (> 3500 km2). Photo: Antony Lynam

One of the perennial and probably most controversial topics in conservation ecology is when is something “too small’. By ‘something’ I mean many things, including population abundance and patch size. We’ve certainly written about the former on many occasions (see here, here, here and here for our work on minimum viable population size), with the associated controversy it elicited.

Now I (sadly) report on the tragedy of the second issue – when is a habitat fragment too small to be of much good to biodiversity?

Published today in the journal Science, Luke Gibson (of No substitute for primary forest fame) and a group of us report disturbing results about the ecological meltdown that has occurred on islands created when the Chiew Larn Reservoir of southern Thailand was flooded nearly 30 years ago by a hydroelectric dam.

As is the case in many parts of the world (e.g., Three Gorges Dam, China), hydroelectric dams can cause major ecological problems merely by flooding vast areas. In the case of Charn Liew, co-author Tony Lynam of Wildlife Conservation Society passed along to me a bit of poignant and emotive history about the local struggle to prevent the disaster.

“As the waters behind the dam were rising in 1987, Seub Nakasathien, the Superintendent of the Khlong Saeng Wildlife Sanctuary, his staff and conservationist friends, mounted an operation to capture and release animals that were caught in the flood waters.

It turned out to be distressing experience for all involved as you can see from the clips here, with the rescuers having only nets and longtail boats, and many animals dying. Ultimately most of the larger mammals disappeared quickly from the islands, leaving just the smaller fauna.

Later Seub moved to Huai Kha Khaeng Wildlife Sanctuary and fought an unsuccessful battle with poachers and loggers, which ended in him taking his own life in despair in 1990. A sad story, and his friend, a famous folk singer called Aed Carabao, wrote a song about Seub, the music of which plays in the video. Read the rest of this entry »





MPs’ ignorance puts national parks in peril

30 08 2013

greedyLed by Bill Laurance, our latest opinion editorial in the Higher Education supplement. Interestingly, it has already spawned a bilious and spittle-flecked response by Queensland’s Acting National Parks Minister, Tim Mander. Given the evidence, who’s side do you take? I’m happy that at least one of the worst culprit state governments is at least now paying some attention to the issue.

LAST week the world was appalled when Ecuador decided to open up one of its iconic national parks for petroleum development, with Leonardo di Caprio being among the chorus of dissenting voices. Yet the world should be even more disappointed in Australia, a far wealthier nation whose parks could be facing even worse threats.

Why is Australia going down this reckless path? It’s all down to the state governments – especially in Victoria, Queensland and NSW.

For the conservative politicians currently holding sway in these States, it seems it’s time to generate some quick cash while cutting park budgets – and never mind the impact on Australia’s imperilled ecosystems and biodiversity.

In Victoria, for instance, land developers are now being allowed to build hotels and other ventures in national parks. In NSW, recreational shooting and possibly logging will be allowed in parks if new legislation is passed. In NSW’s marine parks, bans on shore-based recreational fishing are being lifted [see previous post here].

Other parks in NSW and Queensland are being opened up to livestock grazing. In Morrinya National Park in Queensland, a strip of forest 20 km long was recently cleared for fencing, with new stock-watering tanks being established throughout the park. Read the rest of this entry »





Don’t blame it on the dingo

21 08 2013

dingo angelOur postdoc, Tom Prowse, has just had one of the slickest set of reviews I’ve ever seen, followed by a quick acceptance of what I think is a pretty sexy paper. Earlier this year his paper in Journal of Animal Ecology showed that thylacine (the badly named ‘Tasmanian tiger‘) was most likely not the victim of some unobserved mystery disease, but instead succumbed to what many large predators have/will: human beings. His latest effort now online in Ecology shows that the thylacine and devil extinctions on the Australian mainland were similarly the result of humans and not the scapegoat dingo. But I’ll let him explain:

‘Regime shifts’ can occur in ecosystems when sometimes even a single component is added or changed. Such additions, of say a new predator, or changes such as a rise in temperature, can fundamentally alter core ecosystem functions and processes, causing the ecosystem to switch to some alternative stable state.

Some of the most striking examples of ecological regime shifts are the mass extinctions of large mammals (‘megafauna’) during human prehistory. In Australia, human arrival and subsequent hunting pressure is implicated in the rapid extinction of about 50 mammal species by around 45 thousand years ago. The ensuing alternative stable state was comprised of a reduced diversity of predators, dominated by humans and two native marsupial predators ‑ the thylacine (also known as the marsupial ‘tiger’ or ‘wolf’) and the devil (which is now restricted to Tasmania and threatened by a debilitating, infectious cancer).

Both thylacines and devils lasted on mainland Australia for over 40 thousand years following the arrival of humans. However, a second regime shift resulted in the extinction of both these predators by about 3 thousand years ago, which was coincidentally just after dingoes were introduced to Australia. Dingoes are descended from early domestic dogs and were introduced to northern Australia from Asia by ancient traders approximately 4 thousand years ago. Today, they are Australia’s only top predator remaining, other than invasive European foxes and feral cats. Since the earliest days of European settlement, dingoes have been persecuted because they prey on livestock. During the 1880s, 5614 km of ‘dingo fence’ was constructed to protect south-east Australia’s grazing rangelands from dingo incursions. The fence is maintained to this day, and dingoes are poisoned and shot both inside and outside this barrier, despite mounting evidence that these predators play a key role in maintaining native ecosystems, largely by suppressing invasive predators.

Perhaps because the public perception of dingoes as ‘sheep-killers’ is so firmly entrenched, it has been commonly assumed that dingoes killed off the thylacines and devils on mainland Australia. People who support this view also point out that thylacines and devils persisted on the island of Tasmania, which was never colonised by dingoes (although thylacines went extinct there too in the early 1900s). To date, most discussion of the mainland thylacine and devil extinctions has focused on the possibility that dingoes disrupted the system by ‘exploitation competition’ (eating the same prey), ‘interference competition’ (wasting the native predators’ precious munching time), as well as ‘direct predation’ (dingoes actually eating devils and thylacines). Read the rest of this entry »








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