7 ms·

Misleading stats too. I've seen countless articles mention that 500,000,000 animals have died. I was skeptical as to how you could even devise such a number re

by 55555 7y ago

Misleading stats too. I've seen countless articles mention that 500,000,000 animals have died. I was skeptical as to how you could even devise such a number reliably so I looked into the source of this statistic. First off, this number was devised by a single Uni professor. How? He multiplied the square-mile density of each species by the amount of territory that's burned. Secondly, and he notes this in his estimate, it's 500,000,000 "killed _or affected_", not just killed. Third, for almost all species, there are no density figures, so he just picked the number 10 (lol, yes, seriously). Fourth, roughly 30% of those estimated animals are birds, of which other experts say 99% would survive because, ya know, they can fly away. Of the other 70%, many others would have just walked or slithered or run and gotten away from the fire. Basically some guy just made up a number of animals that exist and everyone else just assumed that 100% of them were killed. Terrible "science." Many bigger news sites have braced themselves for pushback on this stat by adding "and plants" ("500,000,000 animals and plants") so that their use of the statistic can't be criticized later.

Aperocky 7y ago
This is all too common, especially when it comes to politically charged discussion. Imagine saying data is incorrect/impossible and being called cold hearted, unconcerned with future of planet, hate people, or supporting evil or being a shill.
samcday 7y ago
Not sure if you've seen the following statement from University of Sydney, but they're standing by the estimate: https://sydney.edu.au/news-opinion/news/2020/01/03/a-statement-about-the-480-million-animals-killed-in-nsw-bushfire.html https://sydney.edu.au/news-opinion/news/2020/01/03/a-stateme... In fact, they've pointed out the 500 million figure is a conservative estimate, and is likely to be much higher: "... The true loss of animal life is likely to be much higher than 480 million. ..."
- mistermann 7y ago
  > The authors deliberately employed highly conservative estimates in making their calculations. The true mortality is likely to be substantially higher than those estimated. It's a shame the University of Sydney doesn't have access to this study such that they could have included a link so skeptical people could see for themselves the specifics of this alleged conservatism. Not doing that causes my intuition to question the truthiness of these claims, so I will file this item under "Unknown-Suspicious".
  - nl 7y ago
    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_of_Landclearing_the_impacts_of_the_approved_clearing_of_native_vegetation_on_Australian_wildlife_in_New_South_Wales https://www.researchgate.net/publication/318029981_Impacts_o...
Johnny555 7y ago
birds, of which other experts say 99% would survive because, ya know, they can fly away While I can believe many birds can easily survive the initial fire (if the smoke doesn't get them), do they have a 99% one-month survival rate after a large scale disaster like this? Birds can usually only last a couple days without food, and the fires have affected such a large area that many more birds than usual will be seeking food in the remaining areas -- is there enough food to accommodate them all? And it's not just birds that will be seeking food in the non-fire stricken zones, but also their predators.
- nl 7y ago
  I posted this elsewhere in the thread, but a fairly old book[1] has bird mortality rates between 40% and 54% for similar fires. [1] https://books.google.com.au/books?hl=en&lr=&id=4f8anIoS33MC&oi=fnd&pg=PA351&dq=Wildlife+mortality+in+bushfires+in+Australia&ots=kGisLYv0km&sig=81d1pW9C_IVGRyZ8fqJfmHCRHaw#v=onepage&q=Wildlife%20mortality%20in%20bushfires%20in%20Australia&f=false https://books.google.com.au/books?hl=en&lr=&id=4f8anIoS33MC&... (page 358)
krilly 7y ago
The number is meaningless to the public anyway. I have absolutely no frame of reference for how many animals live in a certain area. For all I know, 500m ants get killed by a period of fairly heavy rainfall. It's more annoying when numbers are misrepresented that we DO have real world experience of, for instance sea level rise. Many people are under the impression that global warming will cause skyscrapers to become submerged, or the majority of the Earth's land area to disappear. All within a few decades. People may argue that it's useful for people to believe this, but I don't want a society of useful idiots. I want a society of skeptics.
- nsonha 7y ago
  was watching a video about the sinking of Jakarta. The biggest contributing factor is actually ground water abstraction and consequently, contraction of the city foundation, not sea level rising.
baggy_trough 7y ago
Knowing Australia, there could be 500 million flies in one fire alone but nobody sheds a tear for them.
- samcday 7y ago
  I mean, if I woke up and read that 500 million mosquitoes were victim to the Australian wildfires, I might not be so sad either. But then you watch a video showing the charred carcasses of many beautiful Australian marsupial and bird species littered on the side of the road [1], and you realize jokes aren't really very useful here. [1]: https://www.youtube.com/watch?v=kn1vMTA3OD0 https://www.youtube.com/watch?v=kn1vMTA3OD0
  - 55555 7y ago
    I think they are just pointing out that the people who think they love animals actually only really seem to love cute animals. And when you think about that for a bit, it seems less pure.
atdrummond 7y ago
Given that there are hundreds of thousands to millions of insects per acre of land, the estimate is almost certainly a vast underestimate.
- nsonha 7y ago
  yeah insects are animals I guess. It's sad that we kill trillion of them every year just by our vastly outnumbered existence.
  - HeWhoLurksLate 7y ago
    Okay, we'll run with this for a minute. Would you like to cease existing? I have plans, dude.
nl 7y ago
Third, for almost all species, there are no density figures, so he just picked the number 10 (lol, yes, seriously). Where are you getting that? The density numbers come from this report[1] and I don't see any mention of "picking the number 10" or anything like that. The estimate is for "affected or killed", and has since grown to over 1B[2]. While I agree that birds can fly away (although with habitat destruction that doesnt' always keep them alive), "Of the other 70%, many others would have just walked or slithered or run and gotten away from the fire" is just false. These fires catch people in cars because they are so fast moving. [1] https://www.researchgate.net/publication/318029981_Impacts_of_Landclearing_the_impacts_of_the_approved_clearing_of_native_vegetation_on_Australian_wildlife_in_New_South_Wales/link/5955ce840f7e9b591cd74473/download https://www.researchgate.net/publication/318029981_Impacts_o... [2] https://www.huffingtonpost.com.au/entry/billion-animals-australia-fires_n_5e13be43e4b0843d361778a6?ri18n=true https://www.huffingtonpost.com.au/entry/billion-animals-aust...
- cmroanirgo 7y ago
  Not to mention the spot fires that erupt, several km ahead of the main front, giving animals no where to go. To put that into perspective, where I am, I was getting blackened gum leaves (meaning: highly flammable), but not actual embers when the main fire near me was still 80km away. We started getting cold ash falling when it was 20km away. One spot fire jumped about 5km toward my location (and spread to become 50000ha in it's own right). (The awesome 'firies' stopped it 8km from me).
- microtherion 7y ago
  Interesting! How did you learn the source for the density numbers?
  - nl 7y ago
    I read the Huffington Post report and found it linked. It is also referenced in the Sydney uni press release.
Cogito 7y ago
Just to challenge your scepticism a bit > Fourth, roughly 30% of those estimated animals are birds, of which other experts say 99% would survive because, ya know, they can fly away. Of the other 70%, many others would have just walked or slithered or run and gotten away from the fire. The fires we're talking about here aren't ones you can easily get away from if you're caught by them. If they're near a firebreak of some kind (large river, cliff, etc) the animals may be able to escape, but otherwise these are very fast moving and very hot fires. It's reasonable to think that for animals caught up in the fires, at least for ground dwelling animals, more were severely impacted than were not. I'm not sure about birds. Where did you see the 99% number? The fires can get hot enough to kill you from 100m away, cause firestorms, and are massive. A lot of birds would have needed to fly a very long way to be safe, and I've no reason to think that they either could or did.
- jcranmer 7y ago
  The intellectually honest thing to do here would be to either try to find some precedent study of wildfire mortality for wildlife to get a coarse estimate on what happens, or to admit that you don't know. Instead, we have an "affected" number that is technically not presented as "killed", but we-kinda-sorta-hope-you-interpret-it-as-such. I'm personally frustrated that no one has been able to dredge up an actual study on wildfire mortality patterns.
  - Cogito 7y ago
    I couldn't find the publication myself (though I now see others have posted it in other threads [0]) so I emailed Professor Dickson to get his input. In the meantime I looked for some studies, and found two that are interesting and include some background on the subject. The Responses of Mammals to La Niña (El Niño Southern Oscillation)–Associated Rainfall, Predation, and Wildfire in Central Australia [1] > The responses of vertebrates to wildfires are complex, reflecting the varying food and shelter requirements of different species, their exposure to predation, and other factors. Vertebrates that shelter above the ground and are not particularly mobile are often killed directly by fire (Chew et al. 1959; Newsome et al. 1975; Silveira et al. 1999; Simons 1991). Conversely, species capable of extensive movements such as large predators and birds frequently escape the flames and may increase in abundance after wildfire when food resources become available (Loyn 1997; Newsome et al. 1975).,Burrowing herbivores and omnivores are likely to survive fires and, depending on predation, may increase in abundance after postfire flushes of vegetation (Newsome et al. 1975). Postwild-fire decreases in the abundance of some species have been attributed to a lack of food resources and increased exposure to predation (Groves and Steenhof 1988; Lawrence 1966; Newsome et al. 1975, 1983). Immediate and short‐term responses of bird and mammal assemblages to a subalpine wildfire in the Snowy Mountains, Australia [2] > Over 35 days in January–February 2003, wildfires burnt across much of the subalpine/alpine landscape of south‐eastern Australia, including about 70% of the land above 1500 m in the Snowy Mountains. At the time of the fire, studies of two subalpine faunal assemblages were being undertaken. The opportunity to resurvey the assemblages was taken in order to examine the immediate impact of fire in an environment where it is uncommon but predicted to occur increasingly with global warming. A study area in the Whites River Valley, where the number of bird species was counted monthly from 1996 to 2003, and weekly in late winter–spring from 2000 to 2003, was burnt in one fire. As well as the expected decrease in the number of individual birds, the fire resulted in an immediate decrease in the number of bird species, unlike in previously studied montane forest, with only the regularly wintering species plus the olive whistler and the ground‐feeding flame robin remaining. During the post‐winter avian immigration, few regular spring migrants appeared on burnt sites despite their nearby presence on the unburnt side of the valley. Five of six small mammal trapping grids were burnt. As with fires at lower altitudes, there was an immediate reduction in mammal numbers on burnt grids following the fire, but in addition, one species, Mastacomys fuscus, declined further in the ensuing 2 months both on burnt and unburnt sites. Numbers of Antechinus swainsonii and Rattus fuscipes stabilized until autumn/winter when there was a further decline due to the unavailability of subnivean space to allow winter foraging, allied with a concentration of fox predation on areas still carrying populations of small mammals. [0] https://www.researchgate.net/publication/318029981_Impacts_of_Landclearing_the_impacts_of_the_approved_clearing_of_native_vegetation_on_Australian_wildlife_in_New_South_Wales https://www.researchgate.net/publication/318029981_Impacts_o... [1] https://academic.oup.com/jmammal/article/86/4/689/876336 https://academic.oup.com/jmammal/article/86/4/689/876336 [2] https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1442-9993.2006.01629.x https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1442-9993....
ppp123 7y ago
How do you feel that stat is misleading? Is it too large, too small? Perhaps some articles are using is misleadingly, but it seems like it is a ballpark estimate made by an educated expert. Do you have references for your bird assertions, this is an article from yesterday where dead birds are washing up on shore, with a quote from an expert: "A lot of people are under the impression that birds can easily fly away from a fire, but that’s not true" https://www.theage.com.au/national/victoria/it-s-a-sorry-sight-dead-birds-wash-up-on-mallacoota-s-beaches-20200107-p53plm.html https://www.theage.com.au/national/victoria/it-s-a-sorry-sig...
- jcranmer 7y ago
  For a coarse wildlife estimate like this, the range of uncertainty is probably about two orders of magnitude. So from 500 million "affected", the true range is 5-500 million or 50 million-5 billion, depending on who decided to truncate the range of uncertainty. The conversion factor for "affected" to "killed"... I have no idea what it is, and there is contradictory intuition for its magnitude, so I don't want to trust any number until I see someone actually doing studies of wildfire mortality.
  - 55555 7y ago
    This is my primary point. The margin of error is two orders of magnitude. It's a bit absurd to throw a statistic around when it's such a huge unknown. I guess I'd be happier if margins of error were included with statistics at all times. Otherwise people think they are all equally certain
microtherion 7y ago
> Third, for almost all species, there are no density figures, so he just picked the number 10 This is contradicted by the statement put out by the university of Sydney: https://sydney.edu.au/news-opinion/news/2020/01/03/a-statement-about-the-480-million-animals-killed-in-nsw-bushfire.html https://sydney.edu.au/news-opinion/news/2020/01/03/a-stateme... > Basically some guy just made up a number of animals that exist "some guy" who has published literally hundreds of peer-reviewed articles on related subjects: https://sydney.edu.au/law/about/people/publications/chris.dickman.pdf https://sydney.edu.au/law/about/people/publications/chris.di...
- gruez 7y ago
  >> Third, for almost all species, there are no density figures, so he just picked the number 10 >This is contradicted by the statement put out by the university of Sydney: https://sydney.edu.au/news-opinion/news/2020/01/03/a-stateme.. https://sydney.edu.au/news-opinion/news/2020/01/03/a-stateme.... I quickly skimmed the source that you've linked, and it says nothing about how they handled species with no density figures.
  - nl 7y ago
    The original report he based his estimate on does: https://www.researchgate.net/publication/318029981_Impacts_of_Landclearing_the_impacts_of_the_approved_clearing_of_native_vegetation_on_Australian_wildlife_in_New_South_Wales https://www.researchgate.net/publication/318029981_Impacts_o... > how they handled species with no density figures 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. (page 16)
  - zorpner 7y ago
    I quickly skimmed the source... As the sibling comment notes, this is addressed in the source material. Consider engaging more productively before posting dismissive comments on HN.
waste_monk 7y ago
>roughly 30% of those estimated animals are birds, of which other experts say 99% would survive because, ya know, they can fly away Except it turns out that birds have tiny delicate lungs, and a little bit of inhaled smoke can kill them.
NeedMoreTea 7y ago
You appear to be the some guy making up stuff, you provide no citations for any of your assertions. Birds can fly away ya know, except they don't come with an IFR rating or instruments, a colossal area has burned -- I saw one estimate of around 8.5m ha (edit: which is over 32,000 square miles or more than Scotland's area) burned so far. So where are they flying away to in high temperature blackness, when the fire front might be moving faster than them? What about smoke inhalation, the biggest killer of people in domestic fires? Smoke from the fires has darkened the sky in Chile and New Zealand.
thaumasiotes 7y ago
> Third, for almost all species, there are no density figures, so he just picked the number 10 (lol, yes, seriously). This isn't a problem; most animals have a per-square-mile density higher than 10. The ones with lower density are the big, popular animals for which better statistics exist. > Fourth, roughly 30% of those estimated animals are birds And this is completely impossible. There aren't enough birds. How many were ants?
- exclusiv 7y ago
  A relative of mine had a saying "one fish per square mile" when we'd catch one and then get skunked the rest of the day.
wickedwiesel 7y ago
I am all for scrutiny of claims like this but I cannot verify some of your statements. I would encourage you to actually look at the report that is the basis for the claims. (The report btw is not the work of a single Uni professor but four authors are named.) First, the press release specifically says "revised his estimate of the number of animals killed in bushfires in NSW to more than 800 million animals, with a national impact of more than one billion animals. " [1] You say: "Third, for almost all species, there are no density figures, so he just picked the number 10 (lol, yes, seriously)" When looking at the original report, linked in full text below [0] it reads: > 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. Regarding the birds, there is section 3.4 of the original report where the authors elaborate their stand. For instance, the loss of woodland (in this study the conversion to grassland) drastically reduces the number of birds in that area "90-95% fewer than in intact woodland". Given the size of the current fires it is a stretch to assume that 99% of birds are able to move to other forest and into other birds' habitats and be able to survive their alongside whatever lives there already. [0] - 2007 report by Dickman et al, https://www.researchgate.net/publication/318029981_Impacts_of_Landclearing_the_impacts_of_the_approved_clearing_of_native_vegetation_on_Australian_wildlife_in_New_South_Wales https://www.researchgate.net/publication/318029981_Impacts_o... [1] - press release: https://sydney.edu.au/news-opinion/news/2020/01/08/australian-bushfires-more-than-one-billion-animals-impacted.html https://sydney.edu.au/news-opinion/news/2020/01/08/australia...
- 55555 7y ago
  He revised his estimate from 500 million to 800 million? Did 300 million more animals die in the interim or was his initial margin of error at least +/- 60%?
streb-lo 7y ago
Of course HN votes blind skepticism with no supporting evidence to the top because, ya know, "intellectual honesty."

by 55555 7y ago

Aperocky 7y ago

This is all too common, especially when it comes to politically charged discussion. Imagine saying data is incorrect/impossible and being called cold hearted, unconcerned with future of planet, hate people, or supporting evil or being a shill.

samcday 7y ago

Not sure if you've seen the following statement from University of Sydney, but they're standing by the estimate: https://sydney.edu.au/news-opinion/news/2020/01/03/a-statement-about-the-480-million-animals-killed-in-nsw-bushfire.html https://sydney.edu.au/news-opinion/news/2020/01/03/a-stateme... In fact, they've pointed out the 500 million figure is a conservative estimate, and is likely to be much higher: "... The true loss of animal life is likely to be much higher than 480 million. ..."

mistermann 7y ago
> The authors deliberately employed highly conservative estimates in making their calculations. The true mortality is likely to be substantially higher than those estimated. It's a shame the University of Sydney doesn't have access to this study such that they could have included a link so skeptical people could see for themselves the specifics of this alleged conservatism. Not doing that causes my intuition to question the truthiness of these claims, so I will file this item under "Unknown-Suspicious".
- nl 7y ago
  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_of_Landclearing_the_impacts_of_the_approved_clearing_of_native_vegetation_on_Australian_wildlife_in_New_South_Wales https://www.researchgate.net/publication/318029981_Impacts_o...

Johnny555 7y ago

birds, of which other experts say 99% would survive because, ya know, they can fly away While I can believe many birds can easily survive the initial fire (if the smoke doesn't get them), do they have a 99% one-month survival rate after a large scale disaster like this? Birds can usually only last a couple days without food, and the fires have affected such a large area that many more birds than usual will be seeking food in the remaining areas -- is there enough food to accommodate them all? And it's not just birds that will be seeking food in the non-fire stricken zones, but also their predators.

nl 7y ago
I posted this elsewhere in the thread, but a fairly old book[1] has bird mortality rates between 40% and 54% for similar fires. [1] https://books.google.com.au/books?hl=en&lr=&id=4f8anIoS33MC&oi=fnd&pg=PA351&dq=Wildlife+mortality+in+bushfires+in+Australia&ots=kGisLYv0km&sig=81d1pW9C_IVGRyZ8fqJfmHCRHaw#v=onepage&q=Wildlife%20mortality%20in%20bushfires%20in%20Australia&f=false https://books.google.com.au/books?hl=en&lr=&id=4f8anIoS33MC&... (page 358)

krilly 7y ago

The number is meaningless to the public anyway. I have absolutely no frame of reference for how many animals live in a certain area. For all I know, 500m ants get killed by a period of fairly heavy rainfall. It's more annoying when numbers are misrepresented that we DO have real world experience of, for instance sea level rise. Many people are under the impression that global warming will cause skyscrapers to become submerged, or the majority of the Earth's land area to disappear. All within a few decades. People may argue that it's useful for people to believe this, but I don't want a society of useful idiots. I want a society of skeptics.

nsonha 7y ago
was watching a video about the sinking of Jakarta. The biggest contributing factor is actually ground water abstraction and consequently, contraction of the city foundation, not sea level rising.

baggy_trough 7y ago

Knowing Australia, there could be 500 million flies in one fire alone but nobody sheds a tear for them.

samcday 7y ago
I mean, if I woke up and read that 500 million mosquitoes were victim to the Australian wildfires, I might not be so sad either. But then you watch a video showing the charred carcasses of many beautiful Australian marsupial and bird species littered on the side of the road [1], and you realize jokes aren't really very useful here. [1]: https://www.youtube.com/watch?v=kn1vMTA3OD0 https://www.youtube.com/watch?v=kn1vMTA3OD0
- 55555 7y ago
  I think they are just pointing out that the people who think they love animals actually only really seem to love cute animals. And when you think about that for a bit, it seems less pure.

atdrummond 7y ago

Given that there are hundreds of thousands to millions of insects per acre of land, the estimate is almost certainly a vast underestimate.

nsonha 7y ago
yeah insects are animals I guess. It's sad that we kill trillion of them every year just by our vastly outnumbered existence.
- HeWhoLurksLate 7y ago
  Okay, we'll run with this for a minute. Would you like to cease existing? I have plans, dude.

nl 7y ago

Third, for almost all species, there are no density figures, so he just picked the number 10 (lol, yes, seriously). Where are you getting that? The density numbers come from this report[1] and I don't see any mention of "picking the number 10" or anything like that. The estimate is for "affected or killed", and has since grown to over 1B[2]. While I agree that birds can fly away (although with habitat destruction that doesnt' always keep them alive), "Of the other 70%, many others would have just walked or slithered or run and gotten away from the fire" is just false. These fires catch people in cars because they are so fast moving. [1] https://www.researchgate.net/publication/318029981_Impacts_of_Landclearing_the_impacts_of_the_approved_clearing_of_native_vegetation_on_Australian_wildlife_in_New_South_Wales/link/5955ce840f7e9b591cd74473/download https://www.researchgate.net/publication/318029981_Impacts_o... [2] https://www.huffingtonpost.com.au/entry/billion-animals-australia-fires_n_5e13be43e4b0843d361778a6?ri18n=true https://www.huffingtonpost.com.au/entry/billion-animals-aust...

cmroanirgo 7y ago
Not to mention the spot fires that erupt, several km ahead of the main front, giving animals no where to go. To put that into perspective, where I am, I was getting blackened gum leaves (meaning: highly flammable), but not actual embers when the main fire near me was still 80km away. We started getting cold ash falling when it was 20km away. One spot fire jumped about 5km toward my location (and spread to become 50000ha in it's own right). (The awesome 'firies' stopped it 8km from me).
microtherion 7y ago
Interesting! How did you learn the source for the density numbers?
- nl 7y ago
  I read the Huffington Post report and found it linked. It is also referenced in the Sydney uni press release.

Cogito 7y ago

Just to challenge your scepticism a bit > Fourth, roughly 30% of those estimated animals are birds, of which other experts say 99% would survive because, ya know, they can fly away. Of the other 70%, many others would have just walked or slithered or run and gotten away from the fire. The fires we're talking about here aren't ones you can easily get away from if you're caught by them. If they're near a firebreak of some kind (large river, cliff, etc) the animals may be able to escape, but otherwise these are very fast moving and very hot fires. It's reasonable to think that for animals caught up in the fires, at least for ground dwelling animals, more were severely impacted than were not. I'm not sure about birds. Where did you see the 99% number? The fires can get hot enough to kill you from 100m away, cause firestorms, and are massive. A lot of birds would have needed to fly a very long way to be safe, and I've no reason to think that they either could or did.

jcranmer 7y ago
The intellectually honest thing to do here would be to either try to find some precedent study of wildfire mortality for wildlife to get a coarse estimate on what happens, or to admit that you don't know. Instead, we have an "affected" number that is technically not presented as "killed", but we-kinda-sorta-hope-you-interpret-it-as-such. I'm personally frustrated that no one has been able to dredge up an actual study on wildfire mortality patterns.
- Cogito 7y ago
  I couldn't find the publication myself (though I now see others have posted it in other threads [0]) so I emailed Professor Dickson to get his input. In the meantime I looked for some studies, and found two that are interesting and include some background on the subject. The Responses of Mammals to La Niña (El Niño Southern Oscillation)–Associated Rainfall, Predation, and Wildfire in Central Australia [1] > The responses of vertebrates to wildfires are complex, reflecting the varying food and shelter requirements of different species, their exposure to predation, and other factors. Vertebrates that shelter above the ground and are not particularly mobile are often killed directly by fire (Chew et al. 1959; Newsome et al. 1975; Silveira et al. 1999; Simons 1991). Conversely, species capable of extensive movements such as large predators and birds frequently escape the flames and may increase in abundance after wildfire when food resources become available (Loyn 1997; Newsome et al. 1975).,Burrowing herbivores and omnivores are likely to survive fires and, depending on predation, may increase in abundance after postfire flushes of vegetation (Newsome et al. 1975). Postwild-fire decreases in the abundance of some species have been attributed to a lack of food resources and increased exposure to predation (Groves and Steenhof 1988; Lawrence 1966; Newsome et al. 1975, 1983). Immediate and short‐term responses of bird and mammal assemblages to a subalpine wildfire in the Snowy Mountains, Australia [2] > Over 35 days in January–February 2003, wildfires burnt across much of the subalpine/alpine landscape of south‐eastern Australia, including about 70% of the land above 1500 m in the Snowy Mountains. At the time of the fire, studies of two subalpine faunal assemblages were being undertaken. The opportunity to resurvey the assemblages was taken in order to examine the immediate impact of fire in an environment where it is uncommon but predicted to occur increasingly with global warming. A study area in the Whites River Valley, where the number of bird species was counted monthly from 1996 to 2003, and weekly in late winter–spring from 2000 to 2003, was burnt in one fire. As well as the expected decrease in the number of individual birds, the fire resulted in an immediate decrease in the number of bird species, unlike in previously studied montane forest, with only the regularly wintering species plus the olive whistler and the ground‐feeding flame robin remaining. During the post‐winter avian immigration, few regular spring migrants appeared on burnt sites despite their nearby presence on the unburnt side of the valley. Five of six small mammal trapping grids were burnt. As with fires at lower altitudes, there was an immediate reduction in mammal numbers on burnt grids following the fire, but in addition, one species, Mastacomys fuscus, declined further in the ensuing 2 months both on burnt and unburnt sites. Numbers of Antechinus swainsonii and Rattus fuscipes stabilized until autumn/winter when there was a further decline due to the unavailability of subnivean space to allow winter foraging, allied with a concentration of fox predation on areas still carrying populations of small mammals. [0] https://www.researchgate.net/publication/318029981_Impacts_of_Landclearing_the_impacts_of_the_approved_clearing_of_native_vegetation_on_Australian_wildlife_in_New_South_Wales https://www.researchgate.net/publication/318029981_Impacts_o... [1] https://academic.oup.com/jmammal/article/86/4/689/876336 https://academic.oup.com/jmammal/article/86/4/689/876336 [2] https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1442-9993.2006.01629.x https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1442-9993....

ppp123 7y ago

How do you feel that stat is misleading? Is it too large, too small? Perhaps some articles are using is misleadingly, but it seems like it is a ballpark estimate made by an educated expert. Do you have references for your bird assertions, this is an article from yesterday where dead birds are washing up on shore, with a quote from an expert: "A lot of people are under the impression that birds can easily fly away from a fire, but that’s not true" https://www.theage.com.au/national/victoria/it-s-a-sorry-sight-dead-birds-wash-up-on-mallacoota-s-beaches-20200107-p53plm.html https://www.theage.com.au/national/victoria/it-s-a-sorry-sig...

jcranmer 7y ago
For a coarse wildlife estimate like this, the range of uncertainty is probably about two orders of magnitude. So from 500 million "affected", the true range is 5-500 million or 50 million-5 billion, depending on who decided to truncate the range of uncertainty. The conversion factor for "affected" to "killed"... I have no idea what it is, and there is contradictory intuition for its magnitude, so I don't want to trust any number until I see someone actually doing studies of wildfire mortality.
- 55555 7y ago
  This is my primary point. The margin of error is two orders of magnitude. It's a bit absurd to throw a statistic around when it's such a huge unknown. I guess I'd be happier if margins of error were included with statistics at all times. Otherwise people think they are all equally certain

microtherion 7y ago

> Third, for almost all species, there are no density figures, so he just picked the number 10 This is contradicted by the statement put out by the university of Sydney: https://sydney.edu.au/news-opinion/news/2020/01/03/a-statement-about-the-480-million-animals-killed-in-nsw-bushfire.html https://sydney.edu.au/news-opinion/news/2020/01/03/a-stateme... > Basically some guy just made up a number of animals that exist "some guy" who has published literally hundreds of peer-reviewed articles on related subjects: https://sydney.edu.au/law/about/people/publications/chris.dickman.pdf https://sydney.edu.au/law/about/people/publications/chris.di...

gruez 7y ago
>> Third, for almost all species, there are no density figures, so he just picked the number 10 >This is contradicted by the statement put out by the university of Sydney: https://sydney.edu.au/news-opinion/news/2020/01/03/a-stateme.. https://sydney.edu.au/news-opinion/news/2020/01/03/a-stateme.... I quickly skimmed the source that you've linked, and it says nothing about how they handled species with no density figures.
- nl 7y ago
  The original report he based his estimate on does: https://www.researchgate.net/publication/318029981_Impacts_of_Landclearing_the_impacts_of_the_approved_clearing_of_native_vegetation_on_Australian_wildlife_in_New_South_Wales https://www.researchgate.net/publication/318029981_Impacts_o... > how they handled species with no density figures 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. (page 16)
- zorpner 7y ago
  I quickly skimmed the source... As the sibling comment notes, this is addressed in the source material. Consider engaging more productively before posting dismissive comments on HN.

waste_monk 7y ago

>roughly 30% of those estimated animals are birds, of which other experts say 99% would survive because, ya know, they can fly away Except it turns out that birds have tiny delicate lungs, and a little bit of inhaled smoke can kill them.

NeedMoreTea 7y ago

You appear to be the some guy making up stuff, you provide no citations for any of your assertions. Birds can fly away ya know, except they don't come with an IFR rating or instruments, a colossal area has burned -- I saw one estimate of around 8.5m ha (edit: which is over 32,000 square miles or more than Scotland's area) burned so far. So where are they flying away to in high temperature blackness, when the fire front might be moving faster than them? What about smoke inhalation, the biggest killer of people in domestic fires? Smoke from the fires has darkened the sky in Chile and New Zealand.

thaumasiotes 7y ago

> Third, for almost all species, there are no density figures, so he just picked the number 10 (lol, yes, seriously). This isn't a problem; most animals have a per-square-mile density higher than 10. The ones with lower density are the big, popular animals for which better statistics exist. > Fourth, roughly 30% of those estimated animals are birds And this is completely impossible. There aren't enough birds. How many were ants?

exclusiv 7y ago
A relative of mine had a saying "one fish per square mile" when we'd catch one and then get skunked the rest of the day.

wickedwiesel 7y ago

I am all for scrutiny of claims like this but I cannot verify some of your statements. I would encourage you to actually look at the report that is the basis for the claims. (The report btw is not the work of a single Uni professor but four authors are named.) First, the press release specifically says "revised his estimate of the number of animals killed in bushfires in NSW to more than 800 million animals, with a national impact of more than one billion animals. " [1] You say: "Third, for almost all species, there are no density figures, so he just picked the number 10 (lol, yes, seriously)" When looking at the original report, linked in full text below [0] it reads: > 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. Regarding the birds, there is section 3.4 of the original report where the authors elaborate their stand. For instance, the loss of woodland (in this study the conversion to grassland) drastically reduces the number of birds in that area "90-95% fewer than in intact woodland". Given the size of the current fires it is a stretch to assume that 99% of birds are able to move to other forest and into other birds' habitats and be able to survive their alongside whatever lives there already. [0] - 2007 report by Dickman et al, https://www.researchgate.net/publication/318029981_Impacts_of_Landclearing_the_impacts_of_the_approved_clearing_of_native_vegetation_on_Australian_wildlife_in_New_South_Wales https://www.researchgate.net/publication/318029981_Impacts_o... [1] - press release: https://sydney.edu.au/news-opinion/news/2020/01/08/australian-bushfires-more-than-one-billion-animals-impacted.html https://sydney.edu.au/news-opinion/news/2020/01/08/australia...

55555 7y ago
He revised his estimate from 500 million to 800 million? Did 300 million more animals die in the interim or was his initial margin of error at least +/- 60%?

streb-lo 7y ago

Of course HN votes blind skepticism with no supporting evidence to the top because, ya know, "intellectual honesty."