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Thank you, this is _exactly_ the kind of analysis I'm interested in! (but unfortunately, far too nuanced to be comprehended or covered by media with any sort of

Thank you, this is _exactly_ the kind of analysis I'm interested in! (but unfortunately, far too nuanced to be comprehended or covered by media with any sort of reach). > it appears this pattern of some surviving the immediate fire but 18 months later having disappeared dur to predators and lack of habitat is fairly common. I don't think your reading of this is quite correct (or perhaps the implication that I'm incorrectly reading into it). The species didn't quite "disappear", as all of the ones claimed to have done so after the 1972 fire were able to be tracked during the 1980 fire: > Following the 1972 fire, numbers fell to the lowest level recorded during the study and each population subsequently disappeared from the plot between the 1973 and 1974 winter censuses. The less intense 1980 fire did not lead to extirpation, but numbers of A. agilis, A. swainsonii and R. fuscipes declined as drought conditions persisted through 1983. This suggests to me that they were repopulated according to the carrying capacity of the habitat (which itself recovered), either from areas outside of the study area or from the small populations that remained (the abstract is careful to repeatedly say "disappeared from the plot", a qualifier that you dropped despite it being significant, as sampling has error). These dynamics are what need to be studied, or at least extrapolated from. The study you shared is based on an 0.02 square mile study area (ಠ_ಠ), of a single ecosystem type; It's possible that the vast scale of the current wildfires mean that recovery from external populations is much less likely, but the claim under discussion here is very far off either way. (For more information about these dynamics, the "Population refuges and immigration" section of this paper is interesting). At any rate, the centrally-trumpeted claims that these animals have already died based on habitat destruction is plainly false. I guess I should note that I don't think pushing back against these estimates suggests that this isn't a tragedy, or that it rebuts calls to action against climate change or mitigation or whatever. I just don't think it serves anyone to misrepresent the facts, or in this case, for such a sloppily-calculated, off-the-cuff figure to be spread so widely as gospel. This is exactly the kind of thing that gives anti-science skeptics traction. OTOH, maybe I'm typical-minding too hard here: most people aren't interested in an accurate view of reality in any case, and maybe being dishonest and plying the public with bullshit figures is how things need to be done. Maybe the harm from giving stupid denialists fodder is outweighed by the benefit of inciting stupid non-denialists to care. ¯\_(ツ)_/¯

nl 7y ago
I don't think your reading of this is quite correct (or perhaps the implication that I'm incorrectly reading into it). The species didn't quite "disappear", as all of the ones claimed to have done so after the 1972 fire were able to be tracked during the 1980 fire... This suggests to me that they were repopulated according to the carrying capacity of the habitat (which itself recovered), either from areas outside of the study area or from the small populations that remained Yes, this is my reading too. I didn't mean to imply that they became extinct, just that they were wiped out from the area by the fire. At any rate, the centrally-trumpeted claims that these animals have already died based on habitat destruction is plainly false. I don't understand what this means ("these animals have already died based on habitat destruction is plainly false")? This study showed that the fires wiped out the animals under survey. If the same pattern is shown here we'd expect the majority of small mammals to be dead in the fire areas.
- wutbrodo 7y ago
  > I didn't mean to imply that they became extinct, just that they were wiped out from the area by the fire Right, what I meant was that it's easy to infer from your phrasing (as I did) that the animals were wiped out (even if just locally) in a way whose implications wouldn't include the population being restored (or mostly restored) within a couple years, as was the case for most of the populations studied (a couple of them did permanently dwindle to zero). I don't think this was necessarily implied by your comment, but I thought it'd be better to clarify for our and others readers' benefit. > I don't understand what this means Sorry for the poor phrasing. I'm referring to the central claim parrotted by news articles, that half a billion animals _have_ died during the fires, as opposed to the forecast that half a billion will die due to habitat destruction (which I claim in the rest of the comment is itself a suspect estimate). > This study showed that the fires wiped out the animals under survey. I don't believe this is accurate. They sampled ~zero animals in the study area, which is easily (and much more likely) explained by the animals spending less time in the burned area until the habitat was restored. The surviviros could easily have been leading fulfilling lives 300 yards away (bearing in mind that the study area was a 700x700 ft square). "no animals don't spend time in recently-burned areas" is a substantially different finding from "burned areas cause total animal death". This is why the comparison to the wildfires is hairy. The effect depends a lot more on migration dynamics than simple assumptions of total death based on carrying capacity per species. An additional wrinkle for expanding the dynamic in this study to the scope of all animals affected by the wildfire is the fact that it's limited to small mammals: if I'm not mistaken, it's a fairly basic tenet of ecology that a collapse in prey population due in part to predation is accompanied by a boom in predator population, for obvious reasons (followed by oscillations in both populations until equilibrium is reached).

nl 7y ago

I don't think your reading of this is quite correct (or perhaps the implication that I'm incorrectly reading into it). The species didn't quite "disappear", as all of the ones claimed to have done so after the 1972 fire were able to be tracked during the 1980 fire... This suggests to me that they were repopulated according to the carrying capacity of the habitat (which itself recovered), either from areas outside of the study area or from the small populations that remained Yes, this is my reading too. I didn't mean to imply that they became extinct, just that they were wiped out from the area by the fire. At any rate, the centrally-trumpeted claims that these animals have already died based on habitat destruction is plainly false. I don't understand what this means ("these animals have already died based on habitat destruction is plainly false")? This study showed that the fires wiped out the animals under survey. If the same pattern is shown here we'd expect the majority of small mammals to be dead in the fire areas.

wutbrodo 7y ago
> I didn't mean to imply that they became extinct, just that they were wiped out from the area by the fire Right, what I meant was that it's easy to infer from your phrasing (as I did) that the animals were wiped out (even if just locally) in a way whose implications wouldn't include the population being restored (or mostly restored) within a couple years, as was the case for most of the populations studied (a couple of them did permanently dwindle to zero). I don't think this was necessarily implied by your comment, but I thought it'd be better to clarify for our and others readers' benefit. > I don't understand what this means Sorry for the poor phrasing. I'm referring to the central claim parrotted by news articles, that half a billion animals _have_ died during the fires, as opposed to the forecast that half a billion will die due to habitat destruction (which I claim in the rest of the comment is itself a suspect estimate). > This study showed that the fires wiped out the animals under survey. I don't believe this is accurate. They sampled ~zero animals in the study area, which is easily (and much more likely) explained by the animals spending less time in the burned area until the habitat was restored. The surviviros could easily have been leading fulfilling lives 300 yards away (bearing in mind that the study area was a 700x700 ft square). "no animals don't spend time in recently-burned areas" is a substantially different finding from "burned areas cause total animal death". This is why the comparison to the wildfires is hairy. The effect depends a lot more on migration dynamics than simple assumptions of total death based on carrying capacity per species. An additional wrinkle for expanding the dynamic in this study to the scope of all animals affected by the wildfire is the fact that it's limited to small mammals: if I'm not mistaken, it's a fairly basic tenet of ecology that a collapse in prey population due in part to predation is accompanied by a boom in predator population, for obvious reasons (followed by oscillations in both populations until equilibrium is reached).