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It's amazing the impact that the reintroduction has had. On a recent winter trip there I also learned that the reintroduction literally moved rivers [1]: - Elk

It's amazing the impact that the reintroduction has had. On a recent winter trip there I also learned that the reintroduction literally moved rivers [1]: - Elk quit loitering along streams, so willow and cottonwood shot up, anchoring soil and narrowing channels. - The new woody growth gave beavers lumber; their colonies jumped from one in 1996 to a dozen within fifteen years, raising water tables and rebuilding wetlands. - With healthier riparian zones came deeper pools, colder water, and a surge in native trout and song-bird nests. [1] https://phys.org/news/2025-02-predators-ecosystems-yellowstone-wolves-carnivores.html https://phys.org/news/2025-02-predators-ecosystems-yellowsto...

sushibowl 1y ago
As far as I know, the science on this is far from settled. There is no consensus and the evidence in favor of a trophic cascade in Yellowstone came predominantly from two studies done by the same team/person. Later studies failed to replicate findings. Do wolves fix ecosystems? CSU study debunks claims about Yellowstone reintroduction https://eu.coloradoan.com/story/news/2024/02/09/colorado-state-study-debunks-trophic-cascade-claims-yellowstone-national-park/72508642007/ https://eu.coloradoan.com/story/news/2024/02/09/colorado-sta... A good story: Media bias in trophic cascade research in Yellowstone National Park https://academic.oup.com/book/26688/chapter-abstract/195480918?redirectedFrom=fulltext&login=false#no-access-message https://academic.oup.com/book/26688/chapter-abstract/1954809...
- ChuckMcM 1y ago
  Both links are paywalled so I can't comment on what they say (positive or negative). That said, I did attend an interesting lecture about systems that looks a bit at the Yellowstone as a cautionary tale about extrapolating how a system works from observational data. Basically it came down to there are secondary and tertiary effects from systems variables that express visibly differently depending on both the magnitude of the system elements influence and the time where it it changes. Thus making "simple" conclusions like 'wolves did this' often insufficient to explain system behavior and sometimes outright incorrect. However, the introduction of wolves did, incontrovertibly, add a system element that had not been present before. Exactly what that element was, and how it expressed is up for interpretation :-)
  - ForOldHack 1y ago
    Brilliant observation. Dynamic systems like this are rarely a cut-n-done. Like the study of ozone, with it's seven counter intuitive steps, it is all an evolving study. It also proves the worth of just simple studies over a long period of time. Science used to do a lot of that, and it was very interesting, as many appear on hacker news, but now it seems that cut-n-done grab more popular news. It also bears the question: what longitudinal studies are popular here besides this one, and retro computing?
    - cwmoore 1y ago
      https://www.ons.gov.uk/aboutus/whatwedo/paidservices/longitudinalstudyls https://www.ons.gov.uk/aboutus/whatwedo/paidservices/longitu...
  - aspenmayer 1y ago
    > Both links are paywalled so I can't comment on what they say (positive or negative). Fixed! https://eu.coloradoan.com/story/news/2024/02/09/colorado-state-study-debunks-trophic-cascade-claims-yellowstone-national-park/72508642007/ https://eu.coloradoan.com/story/news/2024/02/09/colorado-sta... | https://archive.is/k0NqZ https://archive.is/k0NqZ https://academic.oup.com/book/26688/chapter-abstract/195480918 https://academic.oup.com/book/26688/chapter-abstract/1954809... | https://annas-archive[.]org/md5/3d5be21998575e23a28fdaa53ff528ed https://annas-archive[.]org/md5/3d5be21998575e23a28fdaa53ff5... (You will have to replace "[.]" with "." in the above link in case that wasn't obvious.)
    - ChuckMcM 1y ago
      Awesome thanks. Added to my libraary. Interesting that the Coloradan study was asking a slightly different question regarding wolves in Colorado vs the magnitude of the wolf impact in Yellowstone. I felt the experimental setup was also good but might quibble that Elk have more impact than just eating, they can squash saplings just by walking on them. The point that Colorado maintains its Elk population by hunting was relevant as well, any impact of wolf predation would be less than it would be on a previously un-predated population. All in all though, I quite agree that the stories of Yellowstone’s wolves likely overstate the specific impact of wolves and understate the system dynamics that had other mechanisms also affecting them. I also recognize that ‘popular’ writing is more about persuasion than facts :-) and it was important to persuade people that wolves weren’t “bad/evil” just predators that had lived there before. Telling that story as a rebalancing is certainly more palatable than saying “Yeah, if we had allowed hunting Elk (and perhaps Bison) in Yellowstone it would have similarly improved.” Generally keeping the human role as apex predator out of the headlines :-). Thanks again, great links.
- bitexploder 1y ago
  https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecm.1598 https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecm.... CSU study
- ricardobeat 1y ago
  That looks like a quite biased interpretation of these studies. Direct quotes: > The average height of willows in fenced and dammed plots 20 years after the initiation of the experiment exceeded 350 cm, while the height in controls averaged less than 180 cm > This suggests that well watered plants could tolerate relatively heavy browsing. It also shows that the absence of engineering by beavers suppressed willow growth to a similar extent as did browsing They posit that the growth in control groups not matching the fenced areas is evidence of wolves reintroduction not having the effects they are said to have. It is a pretty unconvincing argument since there are so many other variables involved. They also prove that IF the wolves have indirectly lead to either the return of beaver dams, or reduced elk browsing, there is undoubtedly an impact in tree growth, which is a positive result regardless. Their theory that things will never return to their original state, and instead will settle into a new alternate equilibrium is probably correct, but does not seem like the definitive blow to the wolf theory that it’s made out to be.
- GlibMonkeyDeath 1y ago
  And this one from the National Park Service web site, funded by NSF: https://www.nps.gov/yell/learn/ys-24-1-the-challenge-of-understanding-northern-yellowstone-elk-dynamics-after-wolf-reintroduction.htm https://www.nps.gov/yell/learn/ys-24-1-the-challenge-of-unde... TL;DR - the observed reduction of the elk herd correlated with wolf introduction, but also with an increase in cougars, grizzly bears, and even bison, all of which either reduce or compete with elk. Human hunting also added pressure, but that has been limited as the herd size reduced. It is complicated.
  - troupo 1y ago
    I also read it as "biodiversity is a good thing"
  - deleted 1y ago
    [deleted]
sghiassy 1y ago
I’ve always found the idea of “restoring” ecosystems a bit philosophically tricky. When we say that reintroducing wolves led to ecological improvements, what’s our reference point? Are we comparing it to Yellowstone 100 years ago? 500? Pre-human settlement? Ecological baselines are inherently arbitrary—there’s no objectively “correct” state of nature to return to. The systems we call degraded are often just different, not necessarily worse. So when we talk about progress in this context, we’re really measuring against a value-laden idea of what we think nature should look like, not some neutral truth. That doesn’t mean rewilding is bad—but I do think we should acknowledge that we’re shaping nature to fit human values, not restoring it to some pure, original state.
- quotemstr 1y ago
  Another example: mosquitos. We can and should drive them to extinction. The species that feed on humans are nowhere food-web-critical. It's an arbitrary and wrong judgement that we should preserve mosquitos just because they happened to evolve with us. So what if eradicating them would be unnatural? So what if it would technically be a reduction in biodiversity? Not everything natural is good or optimal.
  - profsummergig 1y ago
    You seem very well-informed on the matter.
  - ChrisMarshallNY 1y ago
    I remember when it was announced that smallpox was eradicated (Yeah, I'm old enough to have a smallpox vaccination scar). I remember someone moaning about how we had driven a species to extinction. We're a funny lot, really. I've learned not to take us too seriously; especially the folks that take themselves very seriously.
    - tialaramex 1y ago
      It is questionable whether smallpox is alive and so whether it can go extinct. If in some sense it can go extinct it seems both the Americans and Russians are determined to keep it alive "just in case". Nobody was much concerned when we eradicated another infectious virus. Unlike Smallpox there was no "military rationale" for keeping copies on ice, so Rinderpest is gone. It appears that its close human relation, Measles, will be around for a long time though because "I don't believe in facts" trumps "My child has died of a preventable disease". So that's certainly evidence for you're "We're a funny lot" theory.
mlinhares 1y ago
It’s hard to wrap your head around how complex the earth is and how we fucked it up. It’s great to see news like this, it shows we can and should undo the harms we’ve caused.
KurSix 1y ago
It sounds like something out of a fable, but it's literally just ecology doing its thing once balance is restored

sushibowl 1y ago

As far as I know, the science on this is far from settled. There is no consensus and the evidence in favor of a trophic cascade in Yellowstone came predominantly from two studies done by the same team/person. Later studies failed to replicate findings. Do wolves fix ecosystems? CSU study debunks claims about Yellowstone reintroduction https://eu.coloradoan.com/story/news/2024/02/09/colorado-state-study-debunks-trophic-cascade-claims-yellowstone-national-park/72508642007/ https://eu.coloradoan.com/story/news/2024/02/09/colorado-sta... A good story: Media bias in trophic cascade research in Yellowstone National Park https://academic.oup.com/book/26688/chapter-abstract/195480918?redirectedFrom=fulltext&login=false#no-access-message https://academic.oup.com/book/26688/chapter-abstract/1954809...

ChuckMcM 1y ago
Both links are paywalled so I can't comment on what they say (positive or negative). That said, I did attend an interesting lecture about systems that looks a bit at the Yellowstone as a cautionary tale about extrapolating how a system works from observational data. Basically it came down to there are secondary and tertiary effects from systems variables that express visibly differently depending on both the magnitude of the system elements influence and the time where it it changes. Thus making "simple" conclusions like 'wolves did this' often insufficient to explain system behavior and sometimes outright incorrect. However, the introduction of wolves did, incontrovertibly, add a system element that had not been present before. Exactly what that element was, and how it expressed is up for interpretation :-)
- ForOldHack 1y ago
  Brilliant observation. Dynamic systems like this are rarely a cut-n-done. Like the study of ozone, with it's seven counter intuitive steps, it is all an evolving study. It also proves the worth of just simple studies over a long period of time. Science used to do a lot of that, and it was very interesting, as many appear on hacker news, but now it seems that cut-n-done grab more popular news. It also bears the question: what longitudinal studies are popular here besides this one, and retro computing?
  - cwmoore 1y ago
    https://www.ons.gov.uk/aboutus/whatwedo/paidservices/longitudinalstudyls https://www.ons.gov.uk/aboutus/whatwedo/paidservices/longitu...
- aspenmayer 1y ago
  > Both links are paywalled so I can't comment on what they say (positive or negative). Fixed! https://eu.coloradoan.com/story/news/2024/02/09/colorado-state-study-debunks-trophic-cascade-claims-yellowstone-national-park/72508642007/ https://eu.coloradoan.com/story/news/2024/02/09/colorado-sta... | https://archive.is/k0NqZ https://archive.is/k0NqZ https://academic.oup.com/book/26688/chapter-abstract/195480918 https://academic.oup.com/book/26688/chapter-abstract/1954809... | https://annas-archive[.]org/md5/3d5be21998575e23a28fdaa53ff528ed https://annas-archive[.]org/md5/3d5be21998575e23a28fdaa53ff5... (You will have to replace "[.]" with "." in the above link in case that wasn't obvious.)
  - ChuckMcM 1y ago
    Awesome thanks. Added to my libraary. Interesting that the Coloradan study was asking a slightly different question regarding wolves in Colorado vs the magnitude of the wolf impact in Yellowstone. I felt the experimental setup was also good but might quibble that Elk have more impact than just eating, they can squash saplings just by walking on them. The point that Colorado maintains its Elk population by hunting was relevant as well, any impact of wolf predation would be less than it would be on a previously un-predated population. All in all though, I quite agree that the stories of Yellowstone’s wolves likely overstate the specific impact of wolves and understate the system dynamics that had other mechanisms also affecting them. I also recognize that ‘popular’ writing is more about persuasion than facts :-) and it was important to persuade people that wolves weren’t “bad/evil” just predators that had lived there before. Telling that story as a rebalancing is certainly more palatable than saying “Yeah, if we had allowed hunting Elk (and perhaps Bison) in Yellowstone it would have similarly improved.” Generally keeping the human role as apex predator out of the headlines :-). Thanks again, great links.
bitexploder 1y ago
https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecm.1598 https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecm.... CSU study
ricardobeat 1y ago
That looks like a quite biased interpretation of these studies. Direct quotes: > The average height of willows in fenced and dammed plots 20 years after the initiation of the experiment exceeded 350 cm, while the height in controls averaged less than 180 cm > This suggests that well watered plants could tolerate relatively heavy browsing. It also shows that the absence of engineering by beavers suppressed willow growth to a similar extent as did browsing They posit that the growth in control groups not matching the fenced areas is evidence of wolves reintroduction not having the effects they are said to have. It is a pretty unconvincing argument since there are so many other variables involved. They also prove that IF the wolves have indirectly lead to either the return of beaver dams, or reduced elk browsing, there is undoubtedly an impact in tree growth, which is a positive result regardless. Their theory that things will never return to their original state, and instead will settle into a new alternate equilibrium is probably correct, but does not seem like the definitive blow to the wolf theory that it’s made out to be.
GlibMonkeyDeath 1y ago
And this one from the National Park Service web site, funded by NSF: https://www.nps.gov/yell/learn/ys-24-1-the-challenge-of-understanding-northern-yellowstone-elk-dynamics-after-wolf-reintroduction.htm https://www.nps.gov/yell/learn/ys-24-1-the-challenge-of-unde... TL;DR - the observed reduction of the elk herd correlated with wolf introduction, but also with an increase in cougars, grizzly bears, and even bison, all of which either reduce or compete with elk. Human hunting also added pressure, but that has been limited as the herd size reduced. It is complicated.
- troupo 1y ago
  I also read it as "biodiversity is a good thing"
- deleted 1y ago
  [deleted]

sghiassy 1y ago

I’ve always found the idea of “restoring” ecosystems a bit philosophically tricky. When we say that reintroducing wolves led to ecological improvements, what’s our reference point? Are we comparing it to Yellowstone 100 years ago? 500? Pre-human settlement? Ecological baselines are inherently arbitrary—there’s no objectively “correct” state of nature to return to. The systems we call degraded are often just different, not necessarily worse. So when we talk about progress in this context, we’re really measuring against a value-laden idea of what we think nature should look like, not some neutral truth. That doesn’t mean rewilding is bad—but I do think we should acknowledge that we’re shaping nature to fit human values, not restoring it to some pure, original state.

quotemstr 1y ago
Another example: mosquitos. We can and should drive them to extinction. The species that feed on humans are nowhere food-web-critical. It's an arbitrary and wrong judgement that we should preserve mosquitos just because they happened to evolve with us. So what if eradicating them would be unnatural? So what if it would technically be a reduction in biodiversity? Not everything natural is good or optimal.
- profsummergig 1y ago
  You seem very well-informed on the matter.
- ChrisMarshallNY 1y ago
  I remember when it was announced that smallpox was eradicated (Yeah, I'm old enough to have a smallpox vaccination scar). I remember someone moaning about how we had driven a species to extinction. We're a funny lot, really. I've learned not to take us too seriously; especially the folks that take themselves very seriously.
  - tialaramex 1y ago
    It is questionable whether smallpox is alive and so whether it can go extinct. If in some sense it can go extinct it seems both the Americans and Russians are determined to keep it alive "just in case". Nobody was much concerned when we eradicated another infectious virus. Unlike Smallpox there was no "military rationale" for keeping copies on ice, so Rinderpest is gone. It appears that its close human relation, Measles, will be around for a long time though because "I don't believe in facts" trumps "My child has died of a preventable disease". So that's certainly evidence for you're "We're a funny lot" theory.

mlinhares 1y ago

It’s hard to wrap your head around how complex the earth is and how we fucked it up. It’s great to see news like this, it shows we can and should undo the harms we’ve caused.

KurSix 1y ago

It sounds like something out of a fable, but it's literally just ecology doing its thing once balance is restored