I’m clueless about the sign of the effects on wild aquatic animals (based on this project), and the effects on wild aquatic animals could be more important than the effects on farmed aquatic animals.
Reductions in animal agriculture, including aquaculture, have a high risk of backfiring overall, in case they’re bad for wild terrestrial arthropods. In particular, animal agriculture, including aquaculture, tends to decrease wild terrestrial arthropod populations through land use (for crops and/​or pasture), and possibly substantially (Attwood et al., 2008, Tables 3 and 4), so reducing animal agriculture in general can increase wild terrestrial arthropod suffering by increasing their populations.
Aquaculture tends to have smaller effects on wild terrestrial arthropods than land vertebrate farming due to lower land use per kg of output/​protein, and a targeted reduction of aquaculture — and not a broader reduction across animal agriculture in general — will, via substitution effects, shift some animal production towards land vertebrate farming and increase fishing pressure (and have highly uncertain net effects on wild aquatic animals, but actual wild capture production could go up or down overall [1][2]). This could reduce or even flip the wild terrestrial animal effects in 3.
Based on my own unpublished calculations, the targeted reduction of shrimp farming in particular seems good for farmed animals + wild terrestrial animals together (if you think wild arthropods have bad or ~neutral lives in expectation, and your moral weights for shrimp are high enough), although still highly uncertain for wild aquatic animals. However, my calculations need more review.
What are your takeaways for backfire effects from interventions to reduce aquaculture?
I’m clueless about the sign of the effects on wild aquatic animals (based on this project), and the effects on wild aquatic animals could be more important than the effects on farmed aquatic animals.
Reductions in animal agriculture, including aquaculture, have a high risk of backfiring overall, in case they’re bad for wild terrestrial arthropods. In particular, animal agriculture, including aquaculture, tends to decrease wild terrestrial arthropod populations through land use (for crops and/​or pasture), and possibly substantially (Attwood et al., 2008, Tables 3 and 4), so reducing animal agriculture in general can increase wild terrestrial arthropod suffering by increasing their populations.
Aquaculture tends to have smaller effects on wild terrestrial arthropods than land vertebrate farming due to lower land use per kg of output/​protein, and a targeted reduction of aquaculture — and not a broader reduction across animal agriculture in general — will, via substitution effects, shift some animal production towards land vertebrate farming and increase fishing pressure (and have highly uncertain net effects on wild aquatic animals, but actual wild capture production could go up or down overall [1][2]). This could reduce or even flip the wild terrestrial animal effects in 3.
Based on my own unpublished calculations, the targeted reduction of shrimp farming in particular seems good for farmed animals + wild terrestrial animals together (if you think wild arthropods have bad or ~neutral lives in expectation, and your moral weights for shrimp are high enough), although still highly uncertain for wild aquatic animals. However, my calculations need more review.
Not a backfire effect, but work to reduce aquaculture seems to reduce insect and brine shrimp farming in expectation, and this would, on my view, count in its favour. I don’t know if these effects or the effects on wild animals would be more important, because I haven’t really looked into it enough.