Actually, if you took "sentience" seriously, you would also need to ban any captivity or killing.
Well-cared for dogs seem pretty happy, for example. They're in captivity but not suffering, and can live lives with social bonds, play, etc. Being separated from their humans can make dogs distressed. When one gets sick enough, euthanizing it, though sad, is probably the merciful thing to do.
If a small fish is in a large, well-maintained aquarium, is it in pain or distress because of its captivity? I've seen some very well-run aquariums, and if the fish are all suffering, it doesn't seem obvious.
I think the point is if you take their ability to suffer seriously, you don't take actions which subject it to pain or distress. But captivity doesn't strictly necessitate suffering.
But yeah, we could stop eating animals, or penning them in feedlots.
Should we just release them back to nature and possibly let them die out there?
Some of those animals you would need to force to leave.
I had a dog growing up and like you can leave the front door open and occasionally she'd go out it but come meal time she was going back in that door.
This lobbies simply hide or ignore that they don't have alternatives to the problems that are creating and will soon hit hard.
Outside of practical considerations wrt. biodiversity, why should we care? I mean, if you don't think individual members of a species are entitled to a good life, or at least life free of needless cruelty - then why would you care about their species? Conversely, if you think the species should be saved for reasons other than entertainment or practicality, then I think it only makes sense if you think individuals of that species deserve better conditions.
> Why should we care
This is exactly the problem, that animalist evangelists don't care. They do it just for the dopamine rush and the sweet money while avoiding carefully to notice the negative consequences of their acts.
Animalists have a tunnel vision focused in individuals and about not activating a particular random type of receptors (that evolved as a life-saving mechanism). They are blind or cynical about everything else. When we scratch the surface there is a lot of cargo cult ideas, tons of magical thinking and very outdated XVII century scientific knowledge. With luck we can see a thin and unstable crust of real knowledge on life sciences at most.
On the contrary, most of philosophical BS starts from a mistaken belief that categories are a thing. They're not. They're just fuzzy selectors. A "species" is a technical term, and so is a "chair" or a "rivet". Good enough, as long as you don't zoom in on it too closely. If you do, you'll find the boundary of the category is fuzzy (and if you ask another person to zoom in with you, you'll discover your fuzzy boundaries don't fully overlap).
The "basis of life sciences" you refer to is a historical artifact. People like to categorize and give names to things. They did so according to their practical needs and tools they had. We have better tools now - particularly ones that let us see how life ticks. Genetics is pretty much upending the old taxonomy "that is the basis of all live sciences", because up until ~100 years ago, we had no first clue what's actually going on.
And if you look at what the modern life sciences discover, you'll see that organisms indeed break the usual definition of "species" in every possible way.
In a way, species not being a thing is also fundamental to evolution - after all, how would one species evolve into another, if not through intermediary forms that are kinda both, and kinda neither?
> Is also the product of millions years of evolution so when lost, is irreplaceable.
Well, yes. But that doesn't immediately make it valuable. Random googling says the estimate is of about 8 million different species of plants and animals on Earth, with barely a million classified so far. That's a lot of diversity, but losing any one of them hardly matters. Something else will take its place. It may not be exactly the same, but similar enough.
If you disagree, then ask yourself why. Why value "the product of millions years of evolution"? Could it be a practical reason (e.g. it may have evolutionary adaptations or genetic patterns useful for us)? Could it be aesthetic reasons (it's pretty)? Something else? It's good to name it.
(Personally, I mostly care about biodiversity for practical reasons - primarily ecosystem stability, and secondarily medical and biotech research applications.)
There is no sensible answer, because your emotional attachment to the consumption of dead animals, and the very understandable resistance to the idea that you may have supported (and continue to support) needless cruelty of immense proportions has made you blind to "the negative consequences of [your] acts".
On the practical side, since you supposedly care so much about species: Have you ever put any thought to the idea that all the ecological destruction we cause, just to feed the 7 billion animals of a handful of species, has destroyed far far far more species than it has "saved"?
If we stop breeding pigs and cows we won't have the huge amount we do now. The pigs and cows don't care if their species go extinct.
Letting them go into the wild would be cruel since they aren't prepared to exist out there, but letting them die in the wild vs die in a factory farm isn't much worse of a fate.
In reality, we should stop breeding them, send existing aninals to sanctuarys (which we should fund) and be done with it. Within 20 years, all of the existing farm animals will die out from natural causes.
The real moral question is: how do we support the farmers?
We should ensure that they get their wages replaced and get assistance in moving to a less cruel industry than animal farming. There are already groups that help with this, but they'd need funds to scale their work.
Do current cows care about being alive? I'd say yes, but then never being born or being killed should seem about equally bad from their perspective. If anything not existing is worse.
The whole topic becomes a straight farce once we realize that our "conservation" of these species costs us thousands of other, far more ecologically useful species. Like in the rainforest, for example, where we grow feed for cows, and pasture cows.
I’ve never heard (or thought of) this proposal before.
It makes sense from a harm-minimizing perspective, but in practice, even as a vegetarian who thinks the world would be better off if people didn’t eat meat, I’d be okay with the current crop of animals being eaten as the end to factory farming.
IMHO, not my field.
Most of the wild animals that live a time in captivity needs to learn again with human help where obtain again food before to completely return to the wild.
If domesticated species were going to be released, by extrapolation I deduce the matter would be to know to what extent did they lost their instincts (due human selection), and how they could be guided along N generations to recover it (this plant smell is poisonous), or if the above is to much to learn at least were to find the food, for what an habitat would be needed first, in companion of a high number of animals for to keep a high genetic diversity, with migration paths (climate, group mixing, etc).