50B birds live on Earth, new study finds | Hacker News Reader

50B birds live on Earth, new study finds

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65 pointsBreadmaker72 comments

That seems really low. There has to be massive areas of the world with no birds at all. I mean there is, like the sea, but then there are 20 sparrows in my garden.

Its only 8 birds per human. I would have thought there were more as well.

There are 3 trillion trees in the world. 60 trees for every bird. I guess I can look around and see empty trees, but then rarely I see a tree with tens, perhaps hundreds of birds in them.

especially in comparison to cats-killing-bird numbers

"domestic cats, considered a global invasive species, kill 1.4 to 3.7 billion birds in the lower 48 states each year"

https://www.audubon.org/news/cats-pose-even-bigger-threat-bi...

https://www.audubon.org/news/how-stop-cats-killing-birds

I guess your neighbour's thinking the same thing about the same 20 sparrows.

This contributes to a thought I had years ago. We used to smoke in the parking lot; a co-worker would feed the birds that came daily - contrary to fight club, feeding birds around a parking lot of cars does not cause the birds to poop on the cars lol

Anyway - I always wondered - how many birds are in the world? Then walk down the street, around town, where ever - how many dead birds do you see on the side of the road? 1 every once in a great while maybe?

Where do birds go to die? Or are they just eaten right away by their prey? Stray cats? Hawks?

We started feeding pigeons at our 8th floor apartment in india. Above us is just sky where lots of Kites circle. Over time, the pigeons decided our house is their... hospital? They'd show up here when sick. We'd leave food and water out for them, but they were often too sick to eat or drink. Sometimes they'd recover and fly away, but other times they just sit and wait for death (usually 2-3 days). Some corners of the terrace provide shelter from cats that hunt in the apartments so that could be why they choose this place.

Anyway in the last year, I have seen 4 pigeons die here (one eaten by cat). I think birds of prey or cats get to a lot of dying birds first, so we don't often see them. Even when the birds do die a non-violent death, they seem to be able to choose their spot for dying.

> Where do birds go to die? Or are they just eaten right away by their prey? Stray cats? Hawks?

I can distinctly remember seeing a pigeon nose dive mid flight at ~25m height right in front of me. It... just fell.

Still one of the weirdest things I've ever seen. To top it all, a stray cat caught it in literally less than a second after hitting the ground. Not sure if that was nature or someone shot the poor thing with an air gun or something.

I've seen dead animals dissolve into nothing over the course of a few days. So many things feast on even the smallest of corpses. Nature recycles itself quickly.

Two points, from the study itself, 50B is their median estimate but their mean estimate is 428 billion [1]:

> We calculate that there are likely to be ∼50 billion individual birds in the world at present: about six birds for every human on the planet. This represents the midpoint of our estimates (i.e., the median), albeit with considerable uncertainty (Fig. 2). Compared with the median estimate, the mean estimate of the aggregated distribution for all birds in the world was ∼428 billion individual birds (Fig. 2). While we provide an estimate with a wide highest-density interval, our estimate corresponds well with a previous estimate of the number of individual birds in the world by Gaston and Blackburn (37), who estimated that there were between 200 and 400 billion individual birds in the world. Notably, Gaston and Blackburn (37) did not estimate species separately but rather extrapolated from small-scale density estimates in which all bird species were considered equal. We, however, provide data for nearly all the world’s bird species.

This is a massive disparity in their own estimates, and they acknowledge the uncertainty.

As others have noted, they are also not including farmed birds, so this is an estimate of birds in nature.

1. https://www.pnas.org/content/118/21/e2023170118

Interestingly that number is of wild birds. Domesticated chickens are an additional 25 billion birds https://www.statista.com/statistics/263962/number-of-chicken....

Presumably not including chickens... broilers only live for 33 days on average

This study does not seem to consider or count farmed birds, such as chickens (and others). Yet it mentions impact on ecology, as if farmed animals don’t count. Just the farmed birds on earth would add up to 25 billion or more.

https://www.pnas.org/content/118/21/e2023170118

That number was much higher a few hundred years ago I bet. We've wiped out a lot of the biosphere by converting wilderness into cities and farms.

On the other hand, I've read that birds (and rodents) have thrived because of humans. We've killed off or limited the range of their predators. Many birds do well in cities, and unlike ground animals, they aren't stymied by all our roads and highways.

So while the number of species of birds is likely much smaller, in terms of absolute population there might even be in increase.

This is nothing to be proud of though. We might be to the planet what the coronavirus is to humans.

Sadly this isn’t true either. Some species that coexist with humans may be doing better, but they can be counted on one hand. North America’s bird population is 30% less than it was in the 70s.

North America’s wild bird population has declined by 30% since the 70s alone, long after once populous species like the passenger pigeon were hunted to extinction.

For context, the bird population in North America has declined by around 3 billion since the 70s: a 30% decrease. https://www.scientificamerican.com/article/silent-skies-bill...

Which makes the fact that the passenger pigeon once number 3-5 billion individuals in North America all the more staggering. Assuming the 50b number has not gone down significantly, it may have been that 1 out of every 10 birds on the planet was a passenger pigeon.

They say the flocks would black out the sky passing over.

I have read similar accounts of the passenger pigeon and trust them to be mostly truthful, at least relative to what we can hope to see in the present day. However, as you suggest, the 50b number represents bird populations under crisis and does not represent their pre-Industrial levels, or even last Century’s.

I was also thinking of passenger pigeons, but I suspect that - rather than any special prevalence of passenger pigeons specifically - the actual conclusion to draw from that is that 50B globally is a tiny number compared to what biomes there were previously.

I thought the Red-billed quelea was the most abundant bird?

There are about 1.5 billion apparently and they form flocks of 2 million+

Kinda sounds like a question in a FAANG interview.

The referenced study is here: https://www.pnas.org/content/118/21/e2023170118

Interviewer: At a rough estimate, how many birds are there in the entire world?

Applicant: 50 billion

Interviewer: Ah, I see you also read Hacker News!

/culture fit: check/

Wired had an article last week on "interspecies money" to identify and attach monetary value to everything on the planet - including birds and trees - to give agency to these actors.

Sounds like this mission will be more difficult :)

Thanks for sharing the article though

I am not sure what to think of this. Just a quick back of the napkin basic math implies that there are about 18,000-22,000 square feet for every single bird.

Not even 10 per person? Sounds low, thought there were more.

26 billion of those are chickens?

Where do the rest live?

Presumably above the Earth or in the case of burrowing birds, in the Earth.

Exoornithologists disagree.

Imagine the suffering that exists in nature at any given moment. Billions and trillions of creatures in various states of pain, fear, and want. Then multiply all those experiences for every time frame back to the first organisms.

I don't think people think about the implications of a billion years of natural selection.

The obvious solution to this is to eradicate all life. I don't think that's a viable option in the long run.

It can't and shouldn't be our responsibility to end all suffering, rather we should take responsibility for the suffering we cause.

Reminds me of how the Buddhist solves the problem of suffering by minimising wants, and the Christian by forgiving and loving people and the world for their flaws.

And me by taking a nap.

> The obvious solution to this is to eradicate all life.

That implies that suffering is a problem; IMHO it's just part of life and much of what propels us forward. Conversely, Heroin is a drug that can eliminate suffering, but it's pretty clear from the outside that it does not represent the optimal path through existence.

> I don't think that's a viable option in the long run.

That would only start all problems again.

It could be an explanation for the Great Filter though.

Yeah, I think about this. So many small animals die in slow, painful ways (naturally - i.e. centipedes eating mice, preying mantises eating birds). Makes me wonder if eventually in the future there would be some moral prerogative to somehow tame the natural world

> Makes me wonder if eventually in the future there would be some moral prerogative to somehow tame the natural world

That would get at the core of the absolute vs relative morality debate and I don't think humanity will ever settle on that. It's far more likely that a "Prime Directive"-like non-interference law comes into effect instead. The natural world is cruel but heavily interdependent; as long as we assume that each creature or plant has a right to exist and reproduce, all we can do is eliminate our own effects on ecosystems. Humans are nature's worst transmission vector for pathogens, invasive species, habitat destruction, etc and there's little evidence we'd do anything but make the suffering a lot worse.

You're assigning morality to a nervous system which is inherently absurd. Corn doesn't feel fear, it doesn't lament or suffer it just grows. We don't question the morality of capillary action in plants why should we assign morality to animal systems? Won't someone think of the blood salinity of all living things? Is there not a divine optimal amount of salt in all creatures?

Similarly we are foolish to concern ourselves with the quantity of serotonin or histamine in any given creature.

Humans are generally social, we developed to be concerned with our community rather than our individual survival and it has served us well. We developed systems to extend that concern to future generations, and sometimes we disguised them as deities. Now in our ever blooming quest to socialize we are assimilating more species into the fold, but at a point we should stop and ask if our moral tools are overstepping.

Life is just an ongoing chemical reaction. Maybe in the future people will start empathizing with metal and feel a moral prerogative to stop its oxidation. Larry David may be onto something when he asks 'Do you even respect wood!?'

I know you're joking, but...

Isn't rusting metal just metal that's trying to return to its natural form?

There's no reason for calling iron oxide any more natural than metal iron.

There's a famous phrase about humans being Nature's tool for adding plastics into the world.

I feel like you have to believe at least one of these 3:

1) Life is just a chemical reaction, human sadness / happiness don't matter

2) Humans are fundamentally different than other animals - our pain is somehow more real than animal pain

3) Animal pain does matter.

Personally I favor 3)

2 is pretty deep actually. And for me, that's the one I favor (though I don't dismiss 3).

Humans are fundamentally different because that's us. And even between humans, there is a scale. To me, the only real pain is mine. But, I also have the ability to feel other people's pain, so the pain of people close to me is also real, but less so, it is indirect. To feel pain for a random human requires some active thinking. The further we go, the less real pain is, simply because our brain can't process and mirror it.

Animals look a bit like us and show similar pain reaction so we can emphasize somehow. But for everything after plants, we are getting too far. And then, we can introduce computers: can an AI feel pain? How advanced does it have to be if it does? Maybe it is all programs. Unit tests must hurt...

> The further we go, the less real pain is, simply because our brain can't process and mirror it.

But from an ethical perspective, the pain of a random person is just as important, right?

> Animals look a bit like us and show similar pain reaction so we can emphasize somehow. But for everything after plants, we are getting too far.

Animals don't just show similar pain reactions - the biochemical pathways are the exact same. For me, I have to assume basic physical pain is nearly the same, at least for mammals. For plants I don't know. It's possible they have some pain, but I'd expect it to be very different and lesser. For computers I see no reason to think there's any physical pain (though perhaps in the future)

Earth will be uninhabitable not long into the future on an evolutionary timescale. Without action from humans, oceans will boil away within 1 billion years due to the increasing brightness of the sun, and most life will likely die off within about half of that. So in some sense, the suffering of animals will not be for much longer compared to history.

Humans will need to either learn to:

- Terraform the Earth and keep it cool -- this can keep the Earth habitable for maybe 1-2 billion years at most instead of a few hundred million which is the current expectation. After that it will be of no use and the sun will eventually engulf the Earth in ~4 billion

- Not rely on other species or the oceans to survive, and find artificial ways to manufacture food

- Evolve into (i.e. develop) an intelligent but inorganic life form that can withstand higher temperatures and carry on the legacy of intelligent civilization

- Move to Mars or beyond, terraform it, and take animals with us

Considering the complex inter-dependencies of various species (e.g. humans need to eat plants, plants need insects and worms but their numbers are kept in check by birds, birds need huge plants to reproduce, plants also need to eat shit from animals, animals need yet other plants to make said shit, etc.) I have most hope in creating an inorganic lifeform that can reproduce given only light and raw materials available on planets, and without dependence on other life forms.

You think way too small, especially on a scale of a billion years.

Terraforming our planet is a megaengineering project in itself. It's not much of a stretch to imagine megaengineering changing the orbit of earth, or increasing the lifespan of our star by collecting the gases for later use.

You should watch Isaac Arthur the youtube channel.

We just need to accelerate the planet a bit and gradually expand our orbit.

Yes let’s fuck up nature even more, what could ever go wrong

Imagine the joy that exists in nature at any given moment. Billions and trillions of creatures in various states of ecstasy, happiness, and contentment. Then multiply all those experiences for every time frame back to the first organisms.

I don't think people think about the implications of a billion years of the vast experiences life has to offer.

That’s certainly optimistic.

When I think of nature I think of the horrible dilemmas: wolves starving, circling a new mother and her cub.

I think of pestilence, the urgent near insatiable need to find food, stave off predators and yet somehow extol endless energy to mate.

You should talk to a therapist.

Please don't. It does no good and only makes threads worse.

https://hn.algolia.com/?sort=byDate&type=comment&dateRange=a...

It wasn’t a diagnosis, it was a referral.

If you keep posting unsubstantive/flamebait comments, we're going to have to ban you. It looks like you've been doing a lot of that, which is not cool.

If you wouldn't mind reviewing https://news.ycombinator.com/newsguidelines.html and sticking to the rules when posting here, we'd appreciate it.

It’s slightly rude to suggest that I have issues with my mental health because I watch nature documentaries.

It does not make me miserable to think of these things, it’s just life. Life is struggle for the majority of living things with brief intermissions of contentedness- if you think otherwise you’re only kidding yourself (although it doesn’t harm anyone by living that delusion.)

David Attenborough pulls few punches when showing how brutal the food chain is. Keeping your kids safe means others starve. This goes for plants too, it’s surprisingly easy to empathise with tragedies that occur to other species, including flora and fauna.

Pumps the brakes, my dude, it was a joke.

I don't know, I think billions and trillions of creatures are experiencing happiness and joy too. Especially the birds and the bees in the springtime.

Also, greater intelligence and self-awareness brings more suffering. A bird only knows pain. A human with a terminal illness knows it is dying and suffers the psychological consequences.

This is something I think about from time to time, and it saddens me deeply.

I don’t like to see anything or anyone suffer in pain. And the world is full of this - every day hundreds of thousands of creatures die horribly due to predation or accident. Many unheard, or if heard, ignored.

I think that if you were to describe to a sapient alien what pain and suffering is, and then show them the way of things here, they would brand this planet Hell; a place of endless suffering, and horror in abstract, for all eternity.

Yet that’s not all the suffering in the world, I participate in this - I tell myself that the cow butchered for the dinner I ate tonight was butchered humanely; that it did not suffer in death, it was well fed, cared for, was intellectually stimulated, enjoyed the company of it’s companions.

However, I know this is a convenient lie, one I tell myself to mask the truth; the truth is often far from that, the mechanics of industrial farming render this vision obsolete, replaced by a new horror. No less horrifying than the natural order of things, perhaps more so.

Is this world more than the suffering we choose not to see? Of course it is. The world is stark, beautiful and full of life. The order of nature binding it all together is broadly indifferent to suffering and beauty.

I’m only one person, but I’m glad I can think on this, it’s a luxury the majority of other creatures are not granted.

Edit: I may have let my mind carry me away when writing this

Watching some Journey to the Microcosmos videos, and seeing even the tiniest forms of life express struggle and pain has fed my personal doubt that this world might be Hell.

Of course there are many moments of joy and pleasure, but ultimately it ends in a negative score (all the suffering + ultimately dying anyway)

https://youtube.com/c/microcosmos

Some people do, eg https://en.wikipedia.org/wiki/Eradication_of_suffering#Anima... and https://en.wikipedia.org/wiki/Wild_animal_suffering

We haven't even come close to figuring out or even being sufficiently empathetic to the suffering we cause, to other humans and other creatures. I don't think those creatures want or need our pity with regards to suffering that is inherent to life (as well as to joy -- I make a Taoist point there).

The alternative to the suffering (and joy) inherent to advanced (feeling or conscious) life forms is either a universe without advanced life, or very robotic life, or...

Can advanced life evolve, physically or culturally, to a point where individuals aren't predominantly selfish? Selfism is the root of all evil. If you look behind every moral failure or myopic human decision, it's people making very locally (tribal/space/time) optimized decisions at the expense of the greater and longer term good.

Imagine looking at this from the modern "therapeutic" perspective that aims to eliminate suffering -- rather than seeing it as integral part of nature and world around us. Alternatively: imagine being unhappy that life exists around us rather than being happy about it.

It sounds like a reflection of current emotion/mood to me. Also it is something I'd think about if I was a mercenary aiming down at some innocents. 'theyre just going to suffer, nature is so cruel, *yawn BANG'.

It's fun to get this viewpoint on the same thread where the human animal seems convinced it is special. The greediest animal, we are special. We take joy in the misery of others, that's gotta be unique.

Maybe nature wouldn't be so metal if genes could feel pain.

More than half of those are chickens. So it says more about artificial selection.

To ease that thought each bird that suffers only suffer for itself.

That’s life.

If it’s any comfort, life and suffering are temporary.

Well, birds aren't real so...

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