Biodiversity offsetting is off-putting

5 11 2018

Ancient-woodland-has-movedBiodiversity offsets are becoming more popular in Australia and elsewhere as a means to raise money for conservation and restoration while simultaneously promoting economic development (1). However, there are many perverse consequences for biodiversity if they are not set up carefully (1-3).

Biodiversity ‘offsets’ are intended to work in a similar way to carbon offsets1, in that the destruction of a part of an ecosystem (e.g., a native forest or grassland, or a wetland) can be offset by paying to fund the restoration of another, similar ecosystem elsewhere. As such, approval to clear native vegetation usually comes with financial and other conditions.

But there are several problems with biodiversity offsetting, including the inconvenient fact that creating an equivalent ecosystem somewhere takes substantially longer than it does to destroy one somewhere else (e.g., 4). While carbon emitted in one place is essentially the same as that sequestered elsewhere, a forest can take hundreds of years to develop the same biodiversity values and ecological functions it had prior to destruction. Read the rest of this entry »

Ecophysiological feedbacks under climate change

29 10 2018

Variability in heat tolerance among populations modifies the climate-driven periods of diurnal activity expected for ectotherm species. We illustrate this phenomenon for Iberian lizards in a paper we have just published in the Journal of Animal Ecology (blog post reproduced with permission by the Journal; see related blog).

Common wall lizard (Podarcis muralis, male) and three localities where the species is abundant in Spain, left to right including Valdesquí/Madrid (Central System), Peñagolosa/Castellón (Iberian System) and El Portalet/Huesca (The Pyrenees).

Iberia is a wonderful natural laboratory, with a complex blend of flat/hilly, open/woody and coastal/continental terrain, swept by climatic gradients of temperature and moisture. In 2013, I launched a BES-supported project about the thermal ecology of Iberian lizards and managed to drive over much of the Iberian Peninsula in fairly little time. Not being a reptile specialist myself, I was confronted by the consistent observation that lizard populations occupied very different habitats across the known distribution of each of the ~ 25 known Iberian species belonging to the family Lacertidae.

For instance, the common wall lizard (Podarcis muralis) likes water, rocks and mountains, but you can find this pencil-long reptile at the top of a summit, along the slopes or riversides of shallow and deep ravines, on little stones barely surfacing above peatland grasslands, or among the bricks of buildings. These animals must experience different local climates conditional on where they live, and adapt their thermal physiology accordingly.

Having then started a postdoc in Miguel Araújo’s lab — a world-class site for global change ecology and ‘big’ biodiversity patterns — I reviewed a sizeable body of literature looking into large-scale gradients of thermal tolerance. Most of those papers had collated (mostly) one estimate of tolerance from each of tens to thousands of species, then mapped them against regional and global metrics of climate change through sophisticated mathematical frameworks. But these studies rarely accounted for population-level thermal tolerance.

Read the rest of this entry »

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 & kittens

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 »

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

7 09 2018

dead dingoSo, 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 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: 12th Floor, Dumas House
2 Havelock Street, WEST PERTH WA 6005

cc: Department of Biodiversity, Conservation and Attractions (
cc: Brendan Dooley (

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 »

How to feed the world without costing the Earth

5 07 2018

image_normalI’m excited to announce the upcoming public lecture by world-renowned sustainability scientist, Professor Andrew Balmford, at Flinders University on 17 July 2018.

Andrew is Professor of Conservation Science and a Royal Society Wolfson Research Merit Award holder at the Department of Zoology, University of Cambridge, and is on sabbatical at University of Tasmania until December 2018. His main research interests are exploring how conservation might best be reconciled with land-demanding activities such as farming, quantifying the costs and benefits of effective conservation, and examining what works in conservation. In his book Wild Hope (Chicago University Press), he argues that cautious optimism is essential in tackling environmental challenges. Andrew helped establish the Student Conference on Conservation Science, and Earth Optimism.

EcolEvolFlindersLogoProfessor Balmford will be presenting his seminar “How to feed the world without costing the Earth” (hosted by the Ecology & Evolution Research Group) at the Bedford Park Campus of Flinders University in South Lecture Theatre 1, from 12:00-13:00 on 17 July 2018. All are welcome.

Abstract: Globally, agriculture is the greatest threat to biodiversity and a major contributor to anthropogenic greenhouse gas emissions. How we choose to deal with rising human food demand will to a large degree determine the state of biodiversity and the wider environment in the 21st century. Read the rest of this entry »

Personal deterrents can reduce the risk of shark bites

19 06 2018

Shak deterrent testing

Photo: Charlie Huveneers

A little over a week ago, shark ecologist, Charlie Huveneers, and I attempted to write an article in The Conversation about a report we co-wrote regarding the effectiveness of personal shark-deterrent devices (see below for more on the report itself). It’s a great little story, with both immediate policy implications for human safety and great, big potential improvements to shark conservation in general (i.e., if sharks kill fewer people, then perhaps governments would be less inclined to invokes stupid laws to kill sharks). Indeed, sharks aren’t doing very well around the world, mainly because of over-harvest and persecution from unfounded fear.

Anyway, all was going swimmingly until our editor at The Conversation suddenly decided that they wouldn’t publish the piece based on the following funding disclaimer that we had submitted with the article:

This project was funded by the New South Wales Department of Primary Industries Shark Management Strategy Competitive Annual Grants Program, the Government of South Australia, Ocean Guardian Pty Ltd, and the Neiser Foundation. We openly and transparently declare that Ocean Guardian contributed financially to the study, but that Ocean Guardian was not involved in the study design or implementation, nor did they have access to the data post-collection. Nor did Ocean Guardian provide input into data analysis, interpretation, writing of the report, or the conclusions drawn. The study design followed a protocol developed for a previous study, which was not funded by Ocean Guardian. In summary, Ocean Guardian had no opportunity to influence any aspect of the study or its conclusions, apart from providing some financial support to realise the field project (e.g., boat hire, equipment purchase, etc.) in the same manner as the other funding agencies. The South Australian cage-diving industry provided logistical support during the testing of the deterrents.

The long and short of The Conversation‘s negative decision was that one of the companies contributed financially to project. However, as we stated above, they had absolutely no influence in the subsequent experimental design, data collection, analysis, interpretation or report writing.

While normally I’m a big fan of The Conversation, I really think they dropped the ball with this one. Their decision was illogical and unsupported for five main reasons:

  1. There were many funding partners involved, and the Ocean Freedom contribution was in no way the major or even majority share of funding.
  2. Other companies with devices tested could have contributed, but only Ocean Freedom offered.
  3. The study was commissioned by a state government agency (New South Wales Department of Primary Industries), which is not a commercial entity.
  4. As stated in our disclosure, there was no opportunity for manipulating experimental design, data ownership, or post-collection analysis or writing that could have influenced the results, by any funders or contributors.
  5. The disclosure is open, honest, comprehensive and in every way truthful.

So, I’m more than just a little disappointed — and my opinion of the organisation has dropped considerably. That, with the constant barrage of donation requests they send makes me think twice about their journalistic integrity. I challenge others to think carefully before giving them any money.

Regardless, let’s move on to the article itself (which I can publish freely here without the Draconian oversight of The Conversation):

Many things might explain why the number of shark bites appear to be increasing. However, the infrequent occurrence of such events makes it nearly impossible to determine why. Recently, an atypically high rate of shark bites occurred in Western Australia in 2010-2011 and on the north coast of New South Wales in 2015-2016. These highly publicised events — often sensationalised in both traditional and social media — have pressured governments to implement new measures to reduce the risk of shark bites.

The rising pressure to do something to reduce shark bites has prompted the recent development or commercial release of many new personal shark deterrents. Yet, most of these devices lack any rigorous scientific assessment of their effectiveness, meaning that some manufacturers have made unfounded claims about how much their devices dissuade sharks from attacking humans.

However, if a particular type of commercially available shark deterrent happens to be less effective (or completely ineffective) as advertised, it can give users a false sense of security, potentially encouraging some to put themselves at greater risk than is necessary. For example, some surfers and spearfishers probably ignore other mitigation measures, such as beach closures, because they ‘feel safe’ when wearing these products.

Read the rest of this entry »

Greater death rates for invasive rabbits from interacting diseases

30 05 2018

When it comes to death rates for invasive European rabbits (Oryctolagus cuniculus) in Australia, it appears that 1 + 1 = 2.1.

Pt tagged rab with RHD+myxo 1 10-08

Tagged European rabbit kitten infected with myxoma virus, but that died from rabbit haemorrhagic virus disease (RHDV). Photo by David Peacock, Biosecurity South Australia.

“Canberra, we have a problem” — Sure, it’s an old problem and much less of one than it used to be back in the 1950s, but invasive rabbits are nonetheless an ecological, conservation, and financial catastrophe across Australia.

relative rabbit abundance South Australia

Semi-schematic diagram, redrawn using data from Saunders and others and extended to include the recent spread of RHDV2, showing changes in rabbit abundance in relation to the introduction of biological control agents into north-eastern South Australia. Dotted lines indicate uncertainty due to lack of continuous annual data. The broken line indicates a level of about 0.5 rabbits ha-1, below which rabbits must be held to ensure recovery of native pastures and shrubs (from B. Cooke 2018 Vet Rec doi:10.1136/vr.k2105)

Rabbits used to reach plague numbers in much of agricultural and outback Australia, but the introduction and clever manipulation of two rather effective rabbit-specific viruses and insect vectors — first, myxoma virus in 1950, European rabbit fleas in the 1960s to help spread the virus, then Spanish rabbit fleas in the 1990s to increase spread into arid areas, and then rabbit haemorrhagic disease virus (RHDV) in 1995 — have been effective in dropping rabbit abundances by an estimated 75-80% in South Australia alone since the 1950s.

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