Nice answer. :) It’s worth noting that many wild animals in agricultural lands might not be affected too much by the agriculture (well, at least in the case of low-density pasture grazing; I guess crop cultivation changes land’s flora and fauna more radically).
Just counting reptiles in tropical regions and assuming no reptiles anywhere else in the world, my article estimates 10^11 to 10^13 reptiles, compared against a bit more than 10^10 land farm animals. So I’m not sure if the 1000X number is too high. One reason it might be too high is that maybe when people study animal densities, they choose the most animal-dense places to sample from.
That’s a good point about how much they are affected. If only around 10x as many wild land vertebrates are affected, I think it’s pretty reasonable to believe that the effects on farmed land vertebrates are more important without thinking too much about the specifics, given how bad chicken lives seem to be on average. However, if you think a decent share of animal suffering is in dying, then wild vertebrate population effects could easily dominate. I think it’s suspicious at around 100x, and would want to see more details about the magnitudes and directions of the effects on wild land vertebrates.
This is all before considering land invertebrates, but for someone with a lot of moral uncertainty about their moral weight, maybe the most sensible thing to do would be to also support an effective insect welfare/anti-insect farming charity. You could make sure you’re net positive in expectation for both land vertebrates and land invertebrates with a portfolio of interventions.
And then we also need to look at aquatic animals.
Good to know about reptiles. That high end was surprising to me, given that I hardly ever see reptiles (in Canada, though!).
Yeah, I mainly only see snakes and turtles in New York state. This figure shows four reptile species in a tropical forest in Puerto Rico, and three of them are anole lizards. The fourth, Sphaerodactylus klauberi, also seems to be quite small.
I’m unsure whether an anti-insect-farming charity can offset potential wild-invertebrate harm from reducing beef/etc production (though it’s worth remembering that the sign of those side effects of meat isn’t super clear). Rowe (2020) says: “There are currently between 79 billion and 94 billion insects alive on farms globally on average on an average day.” The number of arthropods on a single hectare of pasture can be in the hundreds of millions, so 1000 hectares of arthropod-dense pasture could have as many arthropods as all insect farms. (BTW, apparently a beef cow tends to require a bit less than 1 hectare of pasture.) However, most of these pasture arthropods are mites and springtails, which are vastly smaller than mealworms, crickets, or black soldier flies, so probably each mite or springtail matters several times less (maybe tens or hundreds of times less?) than a farmed insect.
BTW, there may be ~10^10 = 10 billion nematodes per hectare of soil.
If only around 10x as many wild land vertebrates are affected, I think it’s pretty reasonable to believe that the effects on farmed land vertebrates are more important without thinking too much about the specifics, given how bad chicken lives seem to be on average.
Yeah. I like to separate beef from chicken in these discussions because I worry about people taking away a message like “the side effects of meat in general are large and unclear, so don’t worry too much about eating meat”, given that until we have more clarity on the side effects, it seems good to err on the side of not causing lots of chicken suffering. I feel less worried about people feeling uncertainty regarding beef because it’s so much less bad in terms of direct suffering per calorie of food (though beef cows still endure some awful things, like castration and slaughter) and because in some cases it’s plausible that beef reduces net wild-animal suffering (though I remain pretty uncertain about that).
Nice answer. :) It’s worth noting that many wild animals in agricultural lands might not be affected too much by the agriculture (well, at least in the case of low-density pasture grazing; I guess crop cultivation changes land’s flora and fauna more radically).
Just counting reptiles in tropical regions and assuming no reptiles anywhere else in the world, my article estimates 10^11 to 10^13 reptiles, compared against a bit more than 10^10 land farm animals. So I’m not sure if the 1000X number is too high. One reason it might be too high is that maybe when people study animal densities, they choose the most animal-dense places to sample from.
That’s a good point about how much they are affected. If only around 10x as many wild land vertebrates are affected, I think it’s pretty reasonable to believe that the effects on farmed land vertebrates are more important without thinking too much about the specifics, given how bad chicken lives seem to be on average. However, if you think a decent share of animal suffering is in dying, then wild vertebrate population effects could easily dominate. I think it’s suspicious at around 100x, and would want to see more details about the magnitudes and directions of the effects on wild land vertebrates.
This is all before considering land invertebrates, but for someone with a lot of moral uncertainty about their moral weight, maybe the most sensible thing to do would be to also support an effective insect welfare/anti-insect farming charity. You could make sure you’re net positive in expectation for both land vertebrates and land invertebrates with a portfolio of interventions.
And then we also need to look at aquatic animals.
Good to know about reptiles. That high end was surprising to me, given that I hardly ever see reptiles (in Canada, though!).
Yeah, I mainly only see snakes and turtles in New York state. This figure shows four reptile species in a tropical forest in Puerto Rico, and three of them are anole lizards. The fourth, Sphaerodactylus klauberi, also seems to be quite small.
I’m unsure whether an anti-insect-farming charity can offset potential wild-invertebrate harm from reducing beef/etc production (though it’s worth remembering that the sign of those side effects of meat isn’t super clear). Rowe (2020) says: “There are currently between 79 billion and 94 billion insects alive on farms globally on average on an average day.” The number of arthropods on a single hectare of pasture can be in the hundreds of millions, so 1000 hectares of arthropod-dense pasture could have as many arthropods as all insect farms. (BTW, apparently a beef cow tends to require a bit less than 1 hectare of pasture.) However, most of these pasture arthropods are mites and springtails, which are vastly smaller than mealworms, crickets, or black soldier flies, so probably each mite or springtail matters several times less (maybe tens or hundreds of times less?) than a farmed insect.
BTW, there may be ~10^10 = 10 billion nematodes per hectare of soil.
Yeah. I like to separate beef from chicken in these discussions because I worry about people taking away a message like “the side effects of meat in general are large and unclear, so don’t worry too much about eating meat”, given that until we have more clarity on the side effects, it seems good to err on the side of not causing lots of chicken suffering. I feel less worried about people feeling uncertainty regarding beef because it’s so much less bad in terms of direct suffering per calorie of food (though beef cows still endure some awful things, like castration and slaughter) and because in some cases it’s plausible that beef reduces net wild-animal suffering (though I remain pretty uncertain about that).