When a threatened species is found only in one small area, conservationists often move some individuals to another suitable habitat. This practice, called “translocation”, makes the whole species less vulnerable to threats.
In the past, this approach has worked really well for some species, but climate change is creating new problems. Will the climate change at that location in the future, and will it remain suitable for the species of interest? On the other hand, some regions might become appropriate for a threatened species.
This fundamental question is important in a rapidly changing climate, yet it has seldom featured when picking new areas for translocations.
It is enigmatic, in that it lives and nests entirely on the ground, unlike almost all other parrots except the closely related night parrot. And it is one of the many unique animals that make Australia so distinctive from all other parts of the world. But living on the ground has its drawbacks, as the parrot is very vulnerable to foxes and cats.
Its home near the south coast is particularly vulnerable to the effects of climate change. As southwestern Australia becomes warmer and drier, the risk of fire to the parrot increases.
Understanding potential climate change impacts is essential when selecting reintroduction sites. We developed high-precision species distribution models and used these to investigate the effect of climate change on current and historical distributions, and identify locations that will remain, or become, suitable habitat in the future.
Our findings predict that some of the western ground parrot’s former south coast range will become increasingly unsuitable in the future, so reintroductions there may not be a good idea. Four out of 13 potential release sites are likely to become inhospitable to these threatened birds.
On the other hand, many of the former or future sites are likely to become important refuge habitats as the climate continues to warm, and would make an excellent choice for any translocations or reintroductions.
We have given this information to an expert panel, who will use these predictions identify and prioritise areas for management and translocation.
The parrot in the coal mine
Fire is already a significant threat which, combined with predation by feral cats, may have led to the loss of this species from its former home at Fitzgerald River National Park. Many of these threats act together, so they must all be considered and managed alongside climate change.
What’s more, the western ground parrot may be an important indicator for the fate of many other species it currently (or formerly) shares its range with. These include the western whipbird, noisy scrub-bird, and a carnivorous marsupial, the dibbler.
These species are all likely to face the same threats and may be equally affected by the changing climate. Future studies will attempt to model these species and to assess whether all will benefit from similar management.
Many challenges remain for the western ground parrot, including the possible negative genetic impacts of the current small population size, and the increasing risk of damaging fires in a drying and warming climate.
But locating “future-proofed” sites is giving us some hope we can ensure the long term persistence of this enigmatic species, and the myriad other unusual species that occur in the biodiversity hotspot of southwestern Australia.
The authors would like to thank Allan Burbidge and Sarah Comer from the WA Department of Biodiversity Conservation and Attractions for their invaluable help and guidance in putting together this article.
There’s one small issue, though. Despite Taylor’s comments in which he sought to explain away Australia’s 0.7% year-on-year rise in emissions as a product of increased gas investment, actual emissions in the December quarter were in fact down relative to the September 2018 quarter. This is due mainly to the fact that people use much more energy for heating in the July-September period than they do during the milder spring weather of October-December.
Taylor, meanwhile, was discussing the “adjusted” data, which reveals an 0.8% increase between the two quarters.
This might all sound like minor quibbling. But knowing the difference between quarterly and annual figures, and raw and adjusted data – and knowing what’s ultimately the most important metric – is crucial to understanding Australia’s emissions. And it might come in handy next time you’re listening to a politician discussing our progress (or lack thereof) towards tackling climate change.
Highlighting the difference between quarters is problematic, because emissions data are what statisticians describe as “noisy”. Emissions levels jump around from period to period, which can obscure the overall trend.
Quarterly data is important for understanding how Australia is tracking more generally towards doing its fair share on reducing its emissions. But too much stock is put on the noise, and not enough on the underlying trend.
The charts below compare our estimated actual emissions on a quarterly basis (top) with the cumulative emissions for the year leading up to that quarter (here described as the “year-to-quarter emissions” and shown in the lower chart).
These charts, both built on today’s data, make a few things clear.
Quarterly emissions are noisy
The first thing to note is that saying that our emissions are down compared with the previous quarter is hardly remarkable, or worth patting ourselves on the back for. This is especially true if we are comparing the December quarter data, released today, with the data for the preceding quarter.
September quarter emissions are almost always higher than the rest of the year. This is because, while September itself is in spring, the September quarter also covers July and August.
Our winter heating needs are generally met using fossil fuels, whether through electric heaters or natural gas, which is why the September quarter has the highest emissions. In the December quarter, which covers most of spring, our need for heating drops, and so do our emissions.
But if you look beyond the difference between quarters, as in the second chart above, you can see the underlying rising trend in our greenhouse gas emissions.
Cherrypicking the best metric
Readers who follow climate politics may remember the spectacular moment in March when Taylor appeared on ABC’s Insiders opposite Barrie Cassidy.
Many journalists, including those on the Insiders panel that day, responded at the time that Taylor’s claim that emissions had dipped over the preceding three months was true but not meaningful, in the context of an annual rising trend.
But it was not even necessarily true. As is visible in the quarterly chart, emissions were not lower in the September quarter of 2018 than they were in the preceding quarter.
Specifically, Taylor claimed that “total emissions are coming down right now”. This is only true if we are talking about “seasonally adjusted, weather-normalised total emissions”. The adjusted data are shown above. While the adjusted data went down between quarters, the actual emissions went up.
The process of adjustment is not unprincipled, and is used to see through the noise of our emissions data. “Seasonal adjustment” and “weather normalisation” are two separate processes.
Seasonal adjustment refers to the process of adjusting the emissions figures to account for the predictable seasonal fluctuations described earlier. Weather normalisation does the same, but takes into account individual temperature extremes, both hot and cold, during any given period, and adjusts accordingly.
Much as a golf handicap lets us compare the performance of golfers of differing abilities, these data adjustments tell us whether our emissions are tracking higher or lower than we might expect.
But if a golfer with a handicap of 10 goes around the course in 82 shots, we don’t declare that they have actually hit the ball only 72 times.
This is essentially what Taylor did in his interview with Cassidy. It is not correct to refer to these adjusted emissions data as our “total emissions”.
What does data adjustment mean?
Building on this, it is important to note that the adjusted data and actual data often disagree on whether emissions have increased between quarters. Since the Coalition took office in 2013, there have been 21 quarterly emissions data releases.
The actual quarterly emissions have increased nine times between quarters. The adjusted data says there have been 12 of these increases. And they have only agreed on whether there was an increase six times.
When one form of the data shows an increase and the other does not, the minister has a choice about which figure to highlight.
In the September quarter, the actual emissions gave bad news (an increase), and the adjusted emissions gave good news (a reduction). Taylor chose to refer to the adjusted data, as did the then environment minister Melissa Price, who had portfolio responsibility for emissions reduction at the time.
Today, this was flipped. The actual emissions showed good news (a reduction) and the adjusted data showed bad news (an increase).
It’s refreshing, then, to see Taylor choose to focus on the adjusted emissions data this time around, when he could have chosen the spin route and focused on the fact that the raw data showed a decrease between quarters.
So what does it all mean?
What we can say without any equivocation at all is that since 2015, in the wake of the carbon price repeal the preceding July, Australia’s greenhouse emissions have increased. On the government’s own projections , this trend is not expected to change.
Stabilisation is not enough. As the Intergovernmental Panel on Climate Change made clear in its Special Report on 1.5℃ last year, deep cuts are required to ensure a safe climate. The Paris Agreement, while calling on all nations to do their part, says rich countries such as Australia should take the lead.
The need to reduce emissions is pressing. And while the raw emissions figures may be down this quarter, this is not meaningful progress. Far more meaningful is the fact that Australia has no effective policy to limit our impact on the global climate.