While the small body size of sardines and anchovies means that many individuals must be killed to produce a given amount of food, thereby scaling up the moral weight, a meaningful moral cost calculation should extend beyond these direct first-order consequences to account for indirect higher-order consequences, especially given that all food production invariably involves some level of collateral damage, as will be discussed further on.
On the other hand, sardines really are very small, and I reckon you’d need on the order of 100x as many sardines as you’d need salmons to get the same amount of calories. I wonder how many small animals would die to produce the amount of calories of plant-based food you’d get from a sardine? I’d guess <<0.1, but I’d be interested in seeing estimates here as it seems pretty cruxy.
It’s true that because of the small body size, you’d need a large number of sardines or anchovies to match the calories from a larger animal like a salmon. However, it’s worth noting that salmon themselves feed on fish like sardines and anchovies, both in the wild and in aquaculture, where each salmon is typically fed hundreds of small pellagic fish throughout its life.
Regarding the number of crop deaths caused by plant agriculture, it’s difficult to draw firm conclusions based on the limited data currently available, as discussed in the section “Fishing vs. Crop Deaths”.
That said, as explored in the section “Fishing vs. Natural Deaths”, these comparisons may be less relevant if fishing sardines and anchovies is net positive, that is, if their deaths via fishing involve less suffering than they would have experienced otherwise in the wild. In addition, the long-term impacts such as biodiversity loss or climate change are very hard to quantify but could significantly shift the overall ethical calculus even further in favour of eating sardines and anchovies.
Regarding the number of crop deaths caused by plant agriculture, it’s difficult to draw firm conclusions based on the limited data currently available, as discussed in the section “Fishing vs. Crop Deaths”.
That section states
While reliable data on crop deaths is extremely limited[27], it is plausible that these crop deaths may carry a higher total moral cost than fishing sardines and anchovies.
I thought I’d expand on this claim a bit, as I agree with @Erich_Grunewald 🔸 it seems cruxy.
Ultimately I agree, though if I were deriving my opinion solely on the citated paper, “Field Deaths in Plant Agriculture”,[1] the initial calculation based on it makes it seem unlikely. The paper says “Our overall estimate should still be much lower than the one we mentioned at the outset [even if we are morally responsible for deaths from predation]”, which is “over 7.3 billion animals killed each year”. That’s roughly 1 animal killed per human per year.[2] If we estimate mean calorie intake to be 2500 kcal per day, 365.25 days per year, that’s 913,125 kcal per year, for 1 death. 1 sardine is 47kcal,[3] so the initial rough comparison of 913,125⁄47 means that sardines cause 19,428x as many deaths per calorie as crops, excluding insects.
Importantly, the “7.3 billion animals” does not include insects, but, based on Tomasik 2016, cropland probably typically has lower Net Primary Productivity, and lower insect populations, which is probably a good thing (assuming the insects have net-negative lives). So that suggests eating crops has a positive moral impact, despite crop deaths.
However, considering this post, I come to agree with your position that it is plausible that “crop deaths may carry a higher total moral cost than fishing sardines and anchovies” (i.e. that it is plausible that fishing sardines has a positive impact which is greater than the positive impact of farming crops).
Interesting!
On the other hand, sardines really are very small, and I reckon you’d need on the order of 100x as many sardines as you’d need salmons to get the same amount of calories. I wonder how many small animals would die to produce the amount of calories of plant-based food you’d get from a sardine? I’d guess <<0.1, but I’d be interested in seeing estimates here as it seems pretty cruxy.
It’s true that because of the small body size, you’d need a large number of sardines or anchovies to match the calories from a larger animal like a salmon. However, it’s worth noting that salmon themselves feed on fish like sardines and anchovies, both in the wild and in aquaculture, where each salmon is typically fed hundreds of small pellagic fish throughout its life.
Regarding the number of crop deaths caused by plant agriculture, it’s difficult to draw firm conclusions based on the limited data currently available, as discussed in the section “Fishing vs. Crop Deaths”.
That said, as explored in the section “Fishing vs. Natural Deaths”, these comparisons may be less relevant if fishing sardines and anchovies is net positive, that is, if their deaths via fishing involve less suffering than they would have experienced otherwise in the wild. In addition, the long-term impacts such as biodiversity loss or climate change are very hard to quantify but could significantly shift the overall ethical calculus even further in favour of eating sardines and anchovies.
That section states
I thought I’d expand on this claim a bit, as I agree with @Erich_Grunewald 🔸 it seems cruxy.
Ultimately I agree, though if I were deriving my opinion solely on the citated paper, “Field Deaths in Plant Agriculture”,[1] the initial calculation based on it makes it seem unlikely. The paper says “Our overall estimate should still be much lower than the one we mentioned at the outset [even if we are morally responsible for deaths from predation]”, which is “over 7.3 billion animals killed each year”. That’s roughly 1 animal killed per human per year.[2] If we estimate mean calorie intake to be 2500 kcal per day, 365.25 days per year, that’s 913,125 kcal per year, for 1 death. 1 sardine is 47kcal,[3] so the initial rough comparison of 913,125⁄47 means that sardines cause 19,428x as many deaths per calorie as crops, excluding insects.
Importantly, the “7.3 billion animals” does not include insects, but, based on Tomasik 2016, cropland probably typically has lower Net Primary Productivity, and lower insect populations, which is probably a good thing (assuming the insects have net-negative lives). So that suggests eating crops has a positive moral impact, despite crop deaths.
However, considering this post, I come to agree with your position that it is plausible that “crop deaths may carry a higher total moral cost than fishing sardines and anchovies” (i.e. that it is plausible that fishing sardines has a positive impact which is greater than the positive impact of farming crops).
Fischer, B., & Lamey, A. (2018). Field Deaths in Plant Agriculture. Journal of Agricultural and Environmental Ethics 31, 409–428. https://doi.org/10.1007/s10806-018-9733-8
Human population surpassed 7.3 billion in 2014: https://www.worldometers.info/world-population/world-population-by-year/
https://www.nutritionix.com/i/nutritionix/fresh-sardine-1-medium-sardine-4/5b2a87a6caec4140766f457a