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by karaterobot 1650 days ago
Disagree with this. According to this article, birds aren't dying off because people choose the almighty dollar, they're dying because they smash into windows or are hunted by cats. The solution isn't to examine our relationship to abstractions versus reality, it's to put a screen on the window so the bird will notice it in time.
4 comments

That's not what the original paper says. This is why you want to read the actual scientific paper and not the article about it. The researchers, in the article's text, state:

> "Steep declines in North American birds parallel patterns of avian declines emerging globally (14, 15, 22, 24). In particular, depletion of native grassland bird populations in North America, driven by habitat loss and more toxic pesticide use in both breeding and wintering areas (25), mirrors loss of farmland birds throughout Europe and elsewhere (15). Even declines among introduced species match similar declines within these same species’ native ranges (26). Agricultural intensification and urbanization have been similarly linked to declines in insect diversity and biomass (27), with cascading impacts on birds and other consumers (24, 28, 29). Given that birds are one of the best monitored animal groups, birds may also represent the tip of the iceberg, indicating similar or greater losses in other taxonomic groups (28, 30)."

This points to agricultural pesticides having impacts on insect populations, and additionally this mirrors where losses have been most extreme, in grasslands most impacted by agricultural activity:

> "Across breeding biomes, grassland birds showed the largest magnitude of total population loss since 1970—more than 700 million breeding individuals across 31 species— and the largest proportional loss (53%); 74% of grassland species are declining. (Fig. 1 and Table 1)."

I've made it a habit to always seek out the original paper instead of just reading the 'science journalism' take on it, for reasons like this.

https://www.flatheadaudubon.org/wp-content/uploads/2019/10/R...

This illustrates why it's a terrible shame that the overpopulation topic has effectively been silenced and demonized in science conservationism and environmentalism.

I frequently get people becoming wildly irrational and upset at me when I suggest that the current population is not supported by the earth sustainably, let alone a much larger one. They'll angrily insist that the earth's "carrying capacity" is 20, 50, 100 billion people! Or that countries should be looking to increase their populations, or that natural population stability and decline is a terrible thing.

As though we have not _already_ caused (and are continuing to cause) a great extinction event almost entirely before any significant effects from greenhouse gas emissions have made an impact.

Habitat destruction, chemical pollution, mining, mineral and fossil fuel depletion, water depletion and contamination, farming practices and monocultures, human interference, etc., are all just horrific, are responsible for massive destruction and extinction of the environment, and aren't all suddenly going to get magic'ed away the instant we somehow get the GHG pollution thing under control (if we ever do).

The funny thing about that is, if our population was a very healthy, say, 5% of its current level, greenhouse gas emissions would be practically a non-issue too. The problem would literally be solved. Gradually moving toward cleaner and more renewable sources of course should and would happen, but while that was responsibly and efficiently changing, there would be no imminent climate catastrophe occurring.

EDIT: It's happening again.

2430 A.D. by Asimov.

"Earth has established a totally balanced and ecologically stable underground society (similar to that portrayed in Asimov's novel The Caves of Steel). But one man, Cranwitz, regarded as a deviant and eccentric because he keeps a few animals as pets, refuses to get rid of these animals, the last non-human inhabitants of the planet.

He is finally persuaded by his sector representatives to exterminate his pets, but also commits suicide. This leaves Earth in 'perfection', with its fifteen trillion inhabitants, twenty billion tons of human brain and the 'exquisite nothingness of uniformity'."

Greenhouse (specifically carbon dioxide) specifically might be solved, because trees exist and are pretty good at what they do, but I absolutely do not believe that a 95% reduction in population would lead to a consistently-healthy world. I think you dramatically underestimate our ability to pollute in small populations. Consider how bad air pollution was in London during the 1700s and 1800s.
But in the 1700s and 1800s you could leave London and go to the countryside and have very little pollution. That would be wonderful today. Instead we are filling and polluting every space in the world.
Air goes around.
I didn't say a 95% reduction in population would lead to a consistently healthy world. I said if global population was 5% of what it is now, greenhouse gas emissions would practically be a non problem.
Fair enough, and for carbon dioxide I mostly agree. But it definitely seems like this:

>Habitat destruction, chemical pollution, mining, mineral and fossil fuel depletion, water depletion and contamination, farming practices and monocultures, human interference, etc., are all just horrific, are responsible for massive destruction and extinction of the environment, and aren't all suddenly going to get magic'ed away the instant we somehow get the GHG pollution thing under control (if we ever do).

is claiming broad relation to population being above some threshold, since the whole comment is about overpopulation.

The aggregate environmental impact of those things are all quite directly related to population, yes. I don't understand what you're getting at.
What do you think about our ability to raise qualified adults enough to manage the continuing industrial sectors of the planet, if we were 5% of our present number?

Subjectively and with zero rigor I think that possibly 150 to 100 years ago levels of population were capable of creating so much of the modern world. But from the Holocaust to Pol Pot, the Bangladesh civil war, mass exterminations of some of humanity's most capable gene pools is something that I very badly want to be convinced hasn't badly harmed the species potential.

I'm not saying 5% is the correct population mind you, several hundred million people is quite a lot though. Certainly enough to carry on civilization in my opinion.
"the appointed time came to bring to ruin those ruining the earth" Rev 11:18

I find it interesting that ruining of the earth by humans was predicted approx 2,000 years ago.

Sadly we have lived up to the hype.

And, we show no signs of making the wholesale changes needed to turn this ship around.

But, if you're interested in an often pooh-poohed alternative, you may find some comfort reading this: https://www.jw.org/en/bible-teachings/peace-happiness/save-e...

You are not the first "genius" realizing this. Look up Ted Kaczynski. But he was smarter than you because he considered what this reality entails for the ruling classes: Namely the decision whether they shouldn't give up on maintaining the masses once technologically feasible. It is for this reason that it is a taboo and has to remain one. Everything else is propaganda and chatter.
> You are not the first "genius" realizing this.

Found another one.

> and upset at me when I suggest that the current population is not supported by the earth sustainably,

because you are wrong. 100 years ago people said we would all starve when the world population reaches 1 billion people. then we not only not starved but became wealthier as well. Doom predictions are mostly damn wrong.

No it's not because I'm wrong, because you can argue with or debate with people who are wrong (or you believe are wrong) without becoming irrational and angry.

And I'm not making any predictions, just observations. This might come down to semantics on what exactly you suppose sustainable to mean or whether or not it is desirable, but causing an ongoing mass extinction event does not meet my definition of sustainable.

I'm talking about environmental sustainability to be clear (hopefully it was from the context but I may not have been explicit enough). I don't doubt we could physically feed billions more people at least as long as we have cheap energy and fertilizers from fossil fuels if we accepted ever increasing environmental destruction.

> And I'm not making any predictions, just observations.

Claiming we are in the middle of a mass extinction event is a prediction, not an observation. It will become an observation when you have actually seen billions of species disappear over time. You don't extrapolate an extinction based on trends over dozens of years (especially on mostly imperfect data).

No I'm talking about actual observations. I'm not going to nitpick about semantics with you no this. Extinction rates are 2-3 orders of magnitude higher than normal, which is not sustainable.
Antinatalism is a thing, yes.

You're not alone and it doesn't matter if something is popular.

Apart from the adoption rate (no pun intended)

Please be aware there is also the "The Voluntary Human Extinction Movement". https://www.vhemt.org/

It is led by Les Knight.

Here is quick explanation, from their site:

''' VHEMT (pronounced vehement) is a movement not an organization. It’s a movement advanced by people who care about life on planet Earth. We’re not just a bunch of misanthropes and anti-social, Malthusian misfits, taking morbid delight whenever disaster strikes humans. Nothing could be farther from the truth. Voluntary human extinction is the humanitarian alternative to human disasters.

We don’t carry on about how the human race has shown itself to be a greedy, amoral parasite on the once-healthy face of this planet. That type of negativity offers no solution to the inexorable horrors which human activity is causing.

Rather, The Movement presents an encouraging alternative to the callous exploitation and wholesale destruction of Earth’s ecology.

As VHEMT Volunteers know, the hopeful alternative to the extinction of millions of species of plants and animals is the voluntary extinction of one species: Homo sapiens... us. '''

I certainly like the promotional video, "Thank You For Not Breeding".

http://vimeo.com/7652051

This group will go extinct just by following their own philosophy. Brilliant.
Organizations (mostly) don't self-perpetuate through sexual reproduction. It's perfectly possible for the VHEMT to expand if they manage to convince enough people.
Not sure if you're being deliberately obtuse or you actually think what I wrote equates to antinatalism, but no that's not my believe. No more than someone who believes the earth's carrying capacity is 100 billion saying that 200 billion is too many people would be antinatalism.
> I frequently get people becoming wildly irrational and upset at me when I suggest that the current population is not supported by the earth sustainably

Arguing about how many people the earth can sustain is pointless without defining what kind of life you expect people to be living. How many billions can capitalism + western rates of consumption sustain and for how long vs a simpler way of life.

> aren't all suddenly going to get magic'ed away

and neither are all the people deemed excess by your world view, which is probably the part people get riled up about.

> Arguing about how many people the earth can sustain is pointless without defining what kind of life you expect people to be living. How many billions can capitalism + western rates of consumption sustain and for how long vs a simpler way of life.

Not really, 10 billion "simpler way of life" people have huge catastrophic footprints as well. Farming being a major one. But the point was not to come to a precise figure and metrics, it's an unhinged kneejerk reaction to any suggestion that the population is not sustainable. Which it is not.

> and neither are all the people deemed excess by your world view,

This false ad hominem suggests you are one of the people my original post refers to.

_My_ world view deems no person "excess". It acknowledges a simple reality that our population is not sustainable and reducing it or limiting growth is critically important for the environment and makes all other environmental efforts simpler or less severe.

> which is probably the part people get riled up about.

No, it's not. They get unhinged about the idea that population is a serious environmental problem at its current levels let alone increased levels. The (baseless and unfounded) claims they make being that it's not a problem "because earth's carrying capacity is 50 billion people" or other absurd statements along those lines.

They probably get upset as they assume you are implying some moral judgment against having kids. Most people want kids, just like those before us for untold hundreds of thousands of years.
There’s a difference between one kid, two kids, three kids, and that guy who had 150 kids or somesuch.

There isn’t an infinite carrying capacity to any planet, nor is it reasonable to have excess of a singular species for it is at the expense of others.

Some may have hurt feelings if you explain that more than 2 kids increases the population, but then “go forth and multiply” is probably not currently sound guidance, given what we now know, vs what we knew, say, 5 thousand years ago. It was arguably bad judgment to completely finish the great grazing herds and the Mastodons but try telling that to a hungry lot of humans.

The more we come to grips with the human as another animal species, one of many on earth, the easier it is to see how our own hubris is the issue everytime.

To the person above who thought 7 billion humans above wasn’t pushing any planetary limits: while no individual human wants to feel like excess, and certainly homicide is never what is being suggested, the fact remains that a wise human race that wishes to have a healthy planet and lots of resources per capita will steer their population over generations to be healthy.

I’m rather convinced that the same way a rabbit population without predators will suffer disease if it blooms too much, that this is what we are starting to encounter as we brush with the limits of our host in terms of our reckless dominance and destruction on the only known home to life so far…

No one wants to hear about limits or rules but hey, reality called…

No I don't think it's that either: for example many seem to get especially upset when I suggest that most developed countries have naturally slightly declining populations so they should more or less be left alone rather than implement policies to drive population growth.
> This false ad hominem suggests you are one of the people my original post refers to.

It's not an ad hominem, and if you think that my reply is "wildly irrational and upset" then I question if you actually get that kind of reaction in general.

It's merely my interpretation of what you said, since you've given no concrete details and left nearly everything to the imagination of the reader. Given your 5% figure, you are arguing for reducing the population by ~7 billion people, but how? On what timeline? Just saying the world is overpopulated is uninteresting.

> The (baseless and unfounded) claims they make being that it's not a problem "because earth's carrying capacity is 50 billion people" or other absurd statements along those lines.

You've stated that the earth's carrying capacity is 5% of current population, which seems to be equally unfounded.

> _My_ world view deems no person "excess".

So we don't have "too many" people? The world is not OVERpopulated? Because excess means "too many" or "more than needed," so if you're saying there's no excess, then you're saying there's not too many people.

I definitely agree with you, by the way: the world does not have an excess of humans!

We have many more people on earth than can sustainably be supported without continuing environmental damage and depletion.
if we were kangaroos, rabbits, or deer, we would do a population cull on ourselves 'for our own good' (not that I think we should).
It's not so much the abstract idea of depopulation that has people upset at you, it's that every concrete proposal for getting there involves genocide and suffering.
First, no they don't. Look up successes in Thailand, Costa Rica, Iran, South Korea, and other nations that lowered their birth rates through noncoercive means that improved health, longevity, prosperity, equality, and stability.

Second, not lowering birth rates involved billions of people suffering and dying. There is no option where we keep living above sustainable levels without consequence.

No it's not that at all actually. It's a plain head-in-sand denial of reality that I'm talking about encountering.

Same kinds of thinking cause the exact same kinds of knee jerk reactions, denialism, conspiracy theories, etc. when you suggest green house gas emissions are not sustainable and should be reduced too.

And I should say that you're wrong about that genocide assertion too. In most of the countries with the highest consumption and environmental footprints, populations are naturally in slight decline on their own. No genocide or suffering needed to reduce populations in those places.

You seem quite convinced that you have the carrying capacity argument correct. I can understand why: it's really easy to come up with doomsday arguments of this form. Extrapolate any rising trend against any perceived constraint and bingo bango you have your prophecy. Thing is, people have been doing this since the dawn of history, and they've been spectacularly wrong since the dawn of history. Doomer models just never seem to be nearly as clever as real human beings.

One day the doomers might actually get it right for once. I'm not holding my breath, but even if I were, proactive genocide would be a tough sell.

> populations are naturally in slight decline on their own

I am aware.

> No genocide or suffering needed

That depends entirely on why you think this trend is happening, but if you're willing to accept the trend as it stands then we can probably find common ground.

Complete rubbish.

We're past the sustainable carraying capacity because we have already brought about mass extinction events, irreversible destruction of habitat and environment with our existing population (and it even started when the population was far lower, it's just that it's been accelerating). I have the counter example. There is no "model".

Also it's strange you accuse me of being a spectacularly wrong doomer when you were just now spouting easily disproven doomsaying about genocides. Maybe tone down the ad hominems a little at least while you're sitting in your glass house.

populations are naturally in slight decline on their own

Yeah, by maybe 10-20% generation over generation. If your target population is 5% of today, and your strategy is to use the natural population decline of Western countries, you aren't getting to those levels for a good 15-25 generations. 400-700 years or so.

> Yeah, by maybe 10-20% generation over generation.

So my counter-example disproves the absurd claim that any population limitation or reduction requires or devolves into genocide.

> If your target population is 5% of today, and your strategy is to use the natural population decline of Western countries, you aren't getting to those levels for a good 15-25 generations. 400-700 years or so.

I'll assume that math works out for those stated assumptions. So what's the point?

With the Earth's being consumed at unsustainable levels, genocide and suffering are an inevitability. It's just a question of who is going to do it to who.
> I frequently get people becoming wildly irrational and upset at me when I suggest that the current population is not supported by the earth sustainably

Irrationality is doing the same thing over and over again and expecting different results.

Exhibit A
Well, people get wildly irrational at me when I suggest that the only viable option here is for people to migrate from Earth into orbit. Space constraints will go away, because in 3-dimensional space everyone can live in as large of a house as they want but remain in a fast commute to urban centers of space cities. There are plenty of materials available on the moon to build whatever we want with. This can, of course, leave the focus on Earth to shift to biosphere remediation.

After we take full intentional control of the planet's climate and shift 99% of human land use to the project, then I expect it will still be 100 years or more before we get back to pre-industrial natural productivity. This won't happen on its own, I'm assuming we put a large amount of artificial accelerators into to the process. It won't be the same as before humans, but we could quickly get back to the same megafauna numbers as before. Rough equivalents to pre-industrial ecosystems will eventually work out the missing niches.

I suspect part of the reason people have a strong response to your suggestion is that it's patently impractical, and thus easy to pick apart.

To offer one small critique: you suggest that we first need "people to migrate from Earth into orbit," THEN "take full intentional control of the planet's climate" - surely if we have the ability to fully control Earth's climate, we don't need everyone in orbit?

And, since we have to develop the technologies necessary to implement your plan anyway, wouldn't it be easier to just figure out how to remediate the biosphere directly, instead of figuring out how to get everyone into orbit, THEN figure out full planetary climate control, THEN artificially-accelerated natural productivity restoration?

Your comment doesn't add up. I need to ask more questions to triage what your positions are. Let's start with the fairly basic premise that virtually all of us agree on:

1. Current human impact on the planet is unsustainable

Now add these premises:

2. As developing world changes, our impact gets worse 3. As our own standards of living increase, our impact gets worse

Your vision of the Earth doesn't have space migration as part of our path to sustainability. Because of this, you're fighting increasing demands while at the same time needing to reduce total impact dramatically. Say that the equation is:

Impact = (number of people) x (quality of life) x (efficiency)

You can reject either (2) or (3) or both at the cost of some human harm. Most pro-tech people tend to not reject either of these, but you might be an exception. Because of that, you have 2 increasing factors, because you don't have control over the number of people are we're locked into growth for 50 years or something demographically, even with birth rates quickly falling below replacement (which they haven't yet).

There's only 1 factor left in your toolbox - efficiency. We live better but at a lower impact to the planet. Agreed, that's great, but because of (1) and (2) we already have high expectations of this factor. On top of that, we need truly dramatic total reductions in total impact. So if we need 2x improvement (which is probably underestimating) to stay level, then we need maybe 8x or 16x to get where we need to be so that the Earth is moderately healthy. That would be great, but this is magical unicorn-ish thinking. Is this what you're counting on? I want to know.

We can control Earth's climate today by Sulfur geoengineering, which I'm worried that we will not start until it's too late, and even more worried that it may not be globally coordinated which would be disastrous. This is just a band aid, we still need to virtually eliminate Carbon emissions on a time scale we're not prepared for. As long as we are here, then climate intervention will be done for us (our own selfish needs), not for the health of the biosphere.

It sounds like you agree that population levels on Earth are unsustainable and reducing them would help to preserve the environment.

Now certainly you can see why your ideas may be a little harder to accept as the scientific fact that human activity at even much smaller levels as today's population has caused terrible environmental destruction, extinction, etc., and with a lot more room to disagree, but so long as you approach the conversations humbly and with a willingness to consider differing opinions as you would have people consider your opinion I sympathize. Some people just react irrationally.

I think because it's not practical yet. I'm not sure if it ever would be, but if SpaceX gets starship right it brings us one big step closer to that. Also I think most people would prefer to remain on Earth. But moving some kinds of industry to space could be useful. Asteroids contain an abundance of elements that are difficult to extract here on Earth. If much of the demand for them was also in space due to heavy industry there, that might make it viable. Having heavy industry in space like that could really open up orbit and the solar system to us.
It is also just general reading comprehension, as the post begins with what appears to be a fairly accurate summary of the study:

>Experts believe that habitat loss due to agricultural development and intensification is most likely the driving factor.

and then makes recommendations about tinting windows and cats. One does not imply the other.

All of which also mirrors stuff like plastic recycling and water pollution. Individual actions are so incredibly dwarfed by industrial actions that it's almost pointless. We need legislation, not feel-good individual ethics.

Seems more complicated - industrial actions, technology, and personal preferences have intertwined roles.

The most effective thing we could do would be to tax beef (and other meats on a sliding scale), because this would decrease the acreage needed per person. People would howl because they like meat, consumers would also just absorb a lot of the tax instead of actually changing behavior. They'll break out arguments about inequality and social justice (but in truth they like the taste).

Vertical factory-like farms seem very promising to me. These will only target certain groups of foods, which tend to be very leafy and healthy. Government policies can play a big role in advancing this tech because economics are challenging and it needs some more scale to drive the cycle to further cost reduction.

I'm sure that direct farm incentives to reduce pesticide use could help. But there's a reason they're used, and there needs to be a game-plan that doesn't assume the farmer will make massive capital investment into the alternatives.

Brilliant, thank you for that effort, especially the direct link to the PDF. A third of the bird population gone in the 50 years since 1970. As he says in Blood Diamond, "Will god ever forgive us for what we've done to each other? ..." The future is here and the future bites.
Actually, is that really what the article said?

> Experts believe that habitat loss due to agricultural development and intensification is most likely the driving factor.

But I don't think the numbers in the article make sense together.

> wild bird populations in the continental U.S. and Canada have declined by 29 percent—or a total net loss of around three billion birds—since 1970.

> between 365 million and one billion birds die each year across the U.S. as a result of window strikes.)

> pet felines kill some 2.6 billion birds annually in the U.S. alone.

So ... the total decline over 50 years (~3B) is approximately the same as the annual deaths from cats and windows at somewhere between a quarter and a third of all birds? I think this is one of those cases where uncritically accepting estimates from independent sources who used different methods produces an incoherent picture.

The article and numbers are right, it’s just not clearly worded.

I had this same question a couple years back when I read this stat, so I messaged the Cornell Lab Ornithology and one of their reps explained how these numbers make sense.

“We start with a population of breeding adult birds at the beginning of the year. They breed, and multiply, and then the population is "spent" throughout the year on deaths such as window strikes, pesticide poisoning, and cat kills. If the population could keep up with these deaths, we would see a net loss of zero. Unfortunately, instead, we are seeing less and less breeding adult birds at the beginning of each year.

So when we say "we've lost 2.9 Billion birds," what we really mean is, "We've seen a net loss of 2.9 billion breeding adult birds since the 1970's." Back in the 1970's, the breeding season started with about 13 billion adult birds. This year, we had about 10 billion. Throughout the year, they multiply to about 40 billion before they die back. Of that 40 billion, cats kill 2.5 billion.”

I think the honest answer is that we just don't have nearly as much surety around these numbers as you might expect.

I went looking for data on actual bird populations, and I get wildly different estimates.

The 3 billion number comes from the following source (as far as I can tell):

" Critical data were contributed by citizen-science participants in the Audubon Christmas Bird Count, North American Breeding Bird Survey, and other bird-monitoring initiatives. The Partners in Flight Avian Conservation Assessment Database was a critical source for the data. " - https://www.birds.cornell.edu/home/bring-birds-back/

Nat Geo quotes

" New research estimates there are between 50 billion and 430 billion birds on Earth. " - https://www.nationalgeographic.com/animals/article/how-many-...

A lot of articles seem to quote the "at least 50 billion" line, probably based on the above numbers.

Basically - I'd say we have no idea how many birds there really are. Take ALL numbers involved as wild guesses.

Counting population based on deaths alone isn't accurate

If the ecosystem is healthy, a dozen birds dying will make way for a dozen more to replace them

And make outdoor cats illegal. An unpopular opinion no doubt. But from nature photographers to veterinarians, the outdoor cat is not good for anyone, including the cat.
I blame online communities for this.

Cat ladies are insane and organized now. In my city, there’s a group distributing shelters and placing them in various outdoor areas to keep feral cats alive over the winter.

They are as nutty as the pigeon feeders, except the cats kill everything in sight.

We have a group like this, which feeds a couple dozen feral cats on "Kitty Cat Lane." Of course there is science behind the insanity -- toxoplasmosis infections from the cats they love.
Our local Nextdoor exploded when some particularly nutty cat vigilante started stealing cats and spaying them.

I think as society sprawls out and folks have fewer kids, this stuff gets escalated.

These comments are disturbingly out of touch.

'Neuter and Release' programs are common, supported and sanctioned by animal shelters, usually local vets provide their services for free, and the point is to provide basic medical for the animals while at the same time trying to control excess populations.

Calling them 'Nutty cat lady vigilantes' would be like calling people 100 years ago providing shelter for abused women 'Marriage Wreckers'.

This particular group of self-described activists were running a squeegee guy scam with cats.

They were stealing pets and shaking down the owners for cash.

Enough with the petty, denigrating attacks people helping mostly harmless animals, which is a generally good thing. These rescuers/helpers run 'neuter and release' programs and are keen on having population control, not increasing the number of rogue cats.
Mostly harmless to you... What a strange thing to call what is effectively an apex suburban predator that is known to kill for fun with no intention of eating.
They are animals like any other, and this notion of 'apex suburban predator' is nonsense.
Feral cats should be euthanized from a distance. Ask any infectious disease doc about cat bites. And think twice about feral kittens being all innocent, their teeth are like hypodermic needles, and can inject shit into joints. You can lose life and limb from kitty cat bites. These are not cool animals.
Our door cats have existed for millennia. Pesticides have not. I don’t think outdoor cats are the problem. Pesticides have killed most of the bug biomass in the last several decades and now birds are being affected.
I cannot understand why DDT is forbidden, but 10000x more powerful insecticides are not forbidden. WTF? Birds are dropping from the sky in Spring, because they have nothing to eat, because bugs are gone while seeds are not ready yet.

Also, air pollution makes them weak. Birds are much more sensitive to air pollution and CO2 level, because they breathe at much higher rate while they have much lower mass than land animals.

Its a solid point. I'm not sure what the average ownership of cats are, but I would imagine every 3rd or 4th person in my friendship network to own one. I would imagine at least over 100 million cats in north America to which most owners probably let them outside to hunt wild life.
Bob cats, mountain lions, etc used to have the entire US as their range. I suspect the bird population boomed after we got rid of the cats (100-150 years ago). Now that we have house cats they’re dropping again.

Boom-bust cycles for animals are common. I try to reflect what the natural order was 10,000 years ago and reflect. 20,000 years ago, there was an ice sheet over North America - ie no birds.

https://en.m.wikipedia.org/wiki/Laurentide_Ice_Sheet

Unless you're talking about the lynx (which mainly eats hares), the historic ranges of American cats barely overlap with LGM ice cover. It's not very relevant to this discussion.
Would that even be beneficial? If the problem is that there are fewer insects and therefore the birds have less food, then cats suppressing the bird population might have a positive impact on insects, which the birds eat. That might be good for birds too in the long run.

Predators are part of a feedback loop. That the predators in question are housecats makes it a somewhat unnatural feedback loop, but that doesn't necessarily make it bad.

Housecats are part of the food chain as well; they can be killed by cayotes and raccoons, and hawks might sometimes go after a small cat.

Not sure what it is like in the US, but in the UK, the RSPB doesn't seem to think cats are a major cause of bird population decline https://www.rspb.org.uk/birds-and-wildlife/advice/gardening-...
That seems very silly. The concept of an indoor or outdoor cat didn't even exist until one hundred years ago.

https://books.google.com/ngrams/graph?content=outdoor+cat%2C...

>including the cat

But my cat likes going outside. He likes catching birds.

I like birds, i like them alive. I would like your car to not go outside and catch birds.
He didn't say money, he said like money.