The Nonlinear Library EA - The scale of animal agriculture by MichaelStJules
May 16, 2024
07:30
Welcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: The scale of animal agriculture, published by MichaelStJules on May 16, 2024 on The Effective Altruism Forum.
In a table, I combine various estimates of the number of animals farmed with Rethink Priorities' welfare range or moral weight estimates (Fischer, 2023) or my own guesses for others based on them. The table is also accessible here with calculations and some notes for some of the figures.
Farmed animals
Individual welfare range (Rethink Priorities' Fischer, 2023, and my own guesses for others in italics)
Total welfare range-years/tonne produced
Total welfare range of those alive at any time (billions)
Welfare range * number killed per year (billions)
Number alive at any time (billions)
Number killed per year (billions)
Total weight of animals harvested per year (millions of tonnes)
Sources for animal numbers and tonnage
Pigs
0.515
4.1
0.5
0.77
0.98
1.49
123
Šimčikas, 2020 and Our World in Data (a, b)
Cattle (and buffaloes)
0.5
11.1
0.9
0.17
1.7
0.34
76
Šimčikas, 2020 and Our World in Data (a, b)
Sheep and goats
0.5
66.1
1.1
0.57
2.2
1.14
17
Šimčikas, 2020 and Our World in Data (a, b)
Chickens
0.332
56.6
7.9
24.9
23.7
75
139
Šimčikas, 2020 and Our World in Data (a, b)
Fish (excluding wild fishery stocking)
0.089
152.8
9.2
9.9
103
111
60
Šimčikas, 2020, FAO, 2022 (Figure 13)
Fish for wild fishery stocking
0.089
1.3
7.1
15
80
Šimčikas, 2020, Šimčikas, 2019
Decapod shrimp
0.031
1080.3
7.1
13.6
230
440
6.6
Waldhorn & Autric, 2023
Insect larvae (2030 projection)
0.002
438.4
0.78
23.8
391
11905
1.8
2030 production projection by de Jong & Nikolik, 2021 (pdf))
Brine shrimp nauplii
0.0002
98630.1
0.30
108.0
1479
540000
0.003
Boddy/Shrimp Welfare Project, unpublished, tonnage from The Fish Site, 2019
Total of above
123.6
27.7
187.9
2245
552612
224
Humans (for comparison)
1
8.1
0.061
8.1
0.061
Ritchie & Mathieu, 2023
Some notes:
1. When central estimates were not available, I've replaced ranges with my own best guess central estimates.
2. The numbers for insect larvae are based on the projection of production by 2030 by de Jong & Nikolik, 2021 (pdf), for production only in North America and Europe and only for farmed animal feed and pet food, although they expected feed to account for most insect farming, and most investment had been for farms in North America and Europe. I use weights and lifespans reflecting black soldier fly larvae. I use Rethink Priorities' welfare range estimate for silkworms for them.
3. Some of the above estimates may not account for pre-slaughter/pre-harvest mortality, so may understate the number alive at a time or that are killed other than by harvest/slaughter.
4. The figures for "Total weight of animals harvested per year" may be somewhat inconsistent, with some potentially reflecting only meat after removing parts, and others the whole bodies.
5. There are other farmed animals not included above, but the above seems to account for almost all of them (Šimčikas, 2020, Waldhorn & Autric, 2023).
Brine shrimp nauplii
For some background on brine shrimp (Artemia) nauplii (early larvae), see Van Stappen, 1996, The Fish Site, 2019, Brine shrimp - Wikipedia and Aquaculture of brine shrimp - Wikipedia. They are largely used as feed for fish larvae and decapod shrimp larvae. The number estimates are based on unpublished estimates by Aaron Boddy from Shrimp Welfare Project.
I assume, as a guess conditional on being sentient at all, brine shrimp nauplii are sentient for one day before they die, roughly between hatching from the cyst (egg) after being added to tanks as a cyst to feed fish or shrimp larvae, and actually being eaten.
I doubt their (potential) mental capacities have been studied much at all. Their average weights as feed are probably around 5*10^-6 grams,[1] similar to nematodes.[2] Rethink Priorities has been fairly skeptical of nematode sen...
In a table, I combine various estimates of the number of animals farmed with Rethink Priorities' welfare range or moral weight estimates (Fischer, 2023) or my own guesses for others based on them. The table is also accessible here with calculations and some notes for some of the figures.
Farmed animals
Individual welfare range (Rethink Priorities' Fischer, 2023, and my own guesses for others in italics)
Total welfare range-years/tonne produced
Total welfare range of those alive at any time (billions)
Welfare range * number killed per year (billions)
Number alive at any time (billions)
Number killed per year (billions)
Total weight of animals harvested per year (millions of tonnes)
Sources for animal numbers and tonnage
Pigs
0.515
4.1
0.5
0.77
0.98
1.49
123
Šimčikas, 2020 and Our World in Data (a, b)
Cattle (and buffaloes)
0.5
11.1
0.9
0.17
1.7
0.34
76
Šimčikas, 2020 and Our World in Data (a, b)
Sheep and goats
0.5
66.1
1.1
0.57
2.2
1.14
17
Šimčikas, 2020 and Our World in Data (a, b)
Chickens
0.332
56.6
7.9
24.9
23.7
75
139
Šimčikas, 2020 and Our World in Data (a, b)
Fish (excluding wild fishery stocking)
0.089
152.8
9.2
9.9
103
111
60
Šimčikas, 2020, FAO, 2022 (Figure 13)
Fish for wild fishery stocking
0.089
1.3
7.1
15
80
Šimčikas, 2020, Šimčikas, 2019
Decapod shrimp
0.031
1080.3
7.1
13.6
230
440
6.6
Waldhorn & Autric, 2023
Insect larvae (2030 projection)
0.002
438.4
0.78
23.8
391
11905
1.8
2030 production projection by de Jong & Nikolik, 2021 (pdf))
Brine shrimp nauplii
0.0002
98630.1
0.30
108.0
1479
540000
0.003
Boddy/Shrimp Welfare Project, unpublished, tonnage from The Fish Site, 2019
Total of above
123.6
27.7
187.9
2245
552612
224
Humans (for comparison)
1
8.1
0.061
8.1
0.061
Ritchie & Mathieu, 2023
Some notes:
1. When central estimates were not available, I've replaced ranges with my own best guess central estimates.
2. The numbers for insect larvae are based on the projection of production by 2030 by de Jong & Nikolik, 2021 (pdf), for production only in North America and Europe and only for farmed animal feed and pet food, although they expected feed to account for most insect farming, and most investment had been for farms in North America and Europe. I use weights and lifespans reflecting black soldier fly larvae. I use Rethink Priorities' welfare range estimate for silkworms for them.
3. Some of the above estimates may not account for pre-slaughter/pre-harvest mortality, so may understate the number alive at a time or that are killed other than by harvest/slaughter.
4. The figures for "Total weight of animals harvested per year" may be somewhat inconsistent, with some potentially reflecting only meat after removing parts, and others the whole bodies.
5. There are other farmed animals not included above, but the above seems to account for almost all of them (Šimčikas, 2020, Waldhorn & Autric, 2023).
Brine shrimp nauplii
For some background on brine shrimp (Artemia) nauplii (early larvae), see Van Stappen, 1996, The Fish Site, 2019, Brine shrimp - Wikipedia and Aquaculture of brine shrimp - Wikipedia. They are largely used as feed for fish larvae and decapod shrimp larvae. The number estimates are based on unpublished estimates by Aaron Boddy from Shrimp Welfare Project.
I assume, as a guess conditional on being sentient at all, brine shrimp nauplii are sentient for one day before they die, roughly between hatching from the cyst (egg) after being added to tanks as a cyst to feed fish or shrimp larvae, and actually being eaten.
I doubt their (potential) mental capacities have been studied much at all. Their average weights as feed are probably around 5*10^-6 grams,[1] similar to nematodes.[2] Rethink Priorities has been fairly skeptical of nematode sen...