| The report[1] (which is trivial to find) has a section on their estimation methodology and includes reasons why it is conservative (section 2.3): Many species were excluded from estimates because there
is insufficient information on their abundance. The largest omission is the entire NSW bat fauna (37 species), for which no information on density could be found. Many small mammals in semi-arid and arid regions exhibit large fluctuations
in density depending on
the prevailing weather. For example, historical accounts of the long-haired or plague rat (Rattus villosissimus) suggest that densities well in excess of 1000 animals per hectare can be attained after years of good rain31, with the species virtually disappearing again during drought. For such eruptive species, only the low-density population estimates were used. The densities of several common species, such as the brown antechinus (Antechinus stuartii), agile antechinus
(A. agilis), yellow-footed antechinus (A. flavipes) and brushtail possum (Trichosurus vulpecula) have been measured in several studies, with most yielding low to moderate densities but small numbers
of studies yielding very high estimates. To reduce bias arising from these rare high values, means for each species were first calculated as log- transformed densities and then back-transformed to produce normal values. This method was used also by Cogger et al. As noted, the usually lower densities obtained from studies carried out in the tablelands, western slopes and plains were used in preference to the higher estimates obtained in surveys further east. my note: these bushfires are in the East, so the higher estimates would be more appropriate here Several species were omitted from consideration due
to uncertainty about how vegetation clearing would affect them. [1] https://www.researchgate.net/publication/318029981_Impacts_o... |
>> 1.5 METHODOLOGY
>> Calculation of wildlife impacts
>> Given Australia’s megadiversity of species and our comparatively small human population and research base, the density (ie number of individuals in a given area) of relatively few species has been determined with precision. In addition, the number of different species, or species richness, occurring in a given area is not known in great detail for many habitats. Estimates of these values must necessarily be extrapolated from a relatively small number of detailed studies. Therefore the authors have deliberately employed highly conservative estimates in making their calculations. The true mortality is likely to be substantially higher than those estimated in this report.
The authors seem fairly straightforward in admitting that these numbers should be considered unreliable, so no criticism from me on that. However: does this (un)certainty attribute accompany (with appropriate emphasis) the data into subsequent news articles and social media conversations, and ultimately millions of human minds?
>> 2.3 HOW HAVE THESE NUMBERS BEEN ESTIMATED?
(No excerpt because I have nothing particular to highlight.)
Again, from a science perspective, I have no complaints about the study itself, but I do have complaints about how it is being used as the basis of broadcasting a manufactured version of reality into the public psyche, dressed up as reality itself.
Take the University of Sydney article itself...
Headline: "A statement about the 480 million animals killed in NSW bushfires since September"
Article content: "Professor Chris Dickman estimates that 480 million animals have been affected since bushfires in NSW started in September 2019. This statement explains how that figure was calculated. "
See the differences?
a) "killed" --> "affected"
b) "480 million animals [have been] [killed]" --> "it is [estimated that] 480 million animals have been [affected]"
And this is the University of Sydney article, an "authoritative" (able to be trusted as being accurate or true; reliable) institution. Now imagine the hyperbolic distortions of content and certainty that the MSM, Twitterverse, and Reddit hivemind layer on top of this, which is then consumed repeatedly by hundreds of millions of people who consider it to be factual reality. [0] [1]
So, is this a big problem? I have no idea. How would one even estimate the magnitude of risk involved in the general public walking around with (unnecessarily) inaccurate internal representations of reality in their heads? Again, I have no idea. But with human behavior getting stranger by the day, I have a feeling that widespread adamant opposition to even considering this very real aspect of reality may turn out to be not a wise approach. Time will tell I suppose, although it's completely possible no one ever sees this perspective even if it does ultimately result in negative outcomes.
[0] https://www.frontiersin.org/articles/10.3389/fpsyg.2014.0158...
[1] https://www.nature.com/articles/474446a