Summary
- Bivalve aquaculture improves animal welfare as a substitute for meat, fish, and other marine food.
- Possibly improves economic welfare in developing countries.
- Can be financially risky.
- There is a huge opportunity to scale.
- Improves water quality and reduces climate change because they are a carbon sink.
- Second-order effects are likely to be beneficial.
Bivalve aquaculture means farming oysters, mussels, scallops, and other edible molluscs.
Bivalve aquaculture has multiple moderate benefits as summarized above. This means that it tends to fall between the cracks when EAs evaluate its effectiveness, because we often focus on maximizing a particular goal. Indeed, searching for “aquaculture” (not even bivalve aquaculture) returned very few “hits” on this forum.
This is an initial look into this cause area; approximately 10 hours was spent mainly on looking at sources.
Note: I may submit this to the Cause Exploration Prizes contest.
Animal welfare
Bivalves taste good (should be self-evident), and are healthy: “oysters, mussels, scallops, and clams are good for you. They’re loaded with protein, healthy fats, and minerals like iron and manganese.”
Eating bivalves causes less suffering than an equivalent amount of chickens, pigs, cows, and most other animals. Depending on what it substitutes for, it would also reduce crop farming and associated rodent/insect deaths, which are more sentient than bivalves.
Non-EAs are receptive to a proposal to substitute bivalves for other meat. They are not receptive to proposals to go vegetarian/vegan. Bivalves are also healthier than plant-based meat. Therefore, bivalves are the most effective way to reduce overall animal suffering.
Developing countries
Note: Epistemic confidence is low, and requires more research.
But it’s quite likely that bivalve aquaculture can have an enduring positive impact on developing countries. This report claims widespread benefits in Vietnam, for example: “There exists an opportunity to rapidly advance and sophisticate oyster aquaculture in Vietnam by exploring the full economic potential that has environmental, social, and sustainability benefits.”
Even if distribution isn’t developed enough for export, bivalve aquaculture can still provide highly nutritious food locally, as protein is generally rarer.
Financially risky
Note: Epistemic confidence is low, because these are comments on a preliminary request for feedback - more research needed.
Bivalve aquaculture has tail risk, e.g.:
“There are a ton of tail risks that can go wrong and wipe you out. Big one is disease, and the bigger the scale the harder that problem is. A lot of unknown unknowns.”
“Intensive aquaculture is tricky, diseases and anoxic conditions can wipe out entire crops.”
Counterintuitively, this is great for its attractiveness as a funding cause. It means that risk capital is valuable, and also means that the optimal risk-neutral level of bivalve aquaculture should be higher than it is now. It also means that we can be creative in how we approach spending money. For example, paying for insurance policies might be more impactful than investing directly.
Lots of room to scale
“Across the world there is an estimated 1.5 million sq km (579,000 sq miles) of coastline suitable for growing bivalve shellfish. According to Willer, developing just 1% of this could produce enough bivalves to fulfil the protein requirements of more than one billion people.”
It’s possible that a lot of this coastline is located in areas with bad governance. And not all of these places would be accessible or economically viable. But this is a tractable problem (scaling/new technologies) and shows that room to scale is unlikely to be the bottleneck.
Note: more research could uncover the amount of suitable coastline, and a breakdown of whether this coastline is in developed or developing countries, and whether they are already used for other things.
Environmental benefits
Bivalves are great for removing algae, and can clean up polluted water. This is an effective selling point for non-EAs, making cooperation easier with favorable political winds.
They can also ameliorate climate change: “Marine bivalves [...] sequester carbon in their shells as calcium carbonate and may be used to mitigate the effects of climate change.” See also: “The animals that are the source of this food require no feeding, need no antibiotics or agrochemicals to farm. And they actively sequester carbon.” I’m informed that EAs do not care about climate change, but many non-EAs think of climate change as a very high priority. This makes it easier to gain allies for more effective operations and impact.
Second-order effects
Note: epistemic confidence is lower here, as not much time was spent looking into these relative to other areas.
Most second-order effects or minor effects seem positive to me. For example, bivalve farming reduces starvation risk, because it’s likely to be an orthogonal food source, contributing to a balanced food security portfolio.
Additionally, focusing on developing countries before they have "meat-lock-in" seems pretty valuable. This would save “future animals”.
How tractable is it?
It’s no good to know that this is beneficial if it’s too hard. Luckily, “Bivalve aquaculture has proven highly successful in Vietnam. Species are easy to farm and require low-level skills, training, and technology to produce healthy and conditioned animals that are nutrient-packed and ready for the local markets and tourists. Previous ACIAR investment in Vietnam has supported the establishment and rapid growth of the edible oyster industry, which is now thriving, and demonstrates just how important this industry now is as a reliable and nutrient-packed food source.”
If it’s not technically hard, then where is the bottleneck? A possible bottleneck could be a lack of qualified marine biologists. But it’s more likely that this is a billion-dollar philanthropy bill lying on the ground, that no one has picked up because we’re all focused on maximizing single cause outcomes.
Note: needs more research to find out the biggest constraints on increased bivalve aquaculture.
How big is the opportunity?
Bivalves are more expensive than farmed animals at the moment. For example, retail prices at my store:
| Scallops | $49/kg (Australian dollars) |
| Beef | $28/kg |
| Pork | $18/kg |
| Chicken | $13/kg |
This price gap indicates that if there was a large increase in the supply of scallops, there is still ample latent demand to clear the market quantity. Personally, I enjoy the taste of scallops, oysters, mussels, clams more than the meats like beef, pork, chicken. I believe that most consumers would have the same palate, except for a few countries like the United States that have idiosyncratic food preferences.
Who is already working on it?
I haven’t talked with experts in the field, and would love to find out more about this. This is a high priority area for additional research, in order to “catch up” to the knowledge frontier.
Conclusion
Bivalve aquaculture is a high impact cause that has multiple benefits, is more robust to evaluation errors, and is neglected because of its “jack of all trades” positioning. It is a high priority for additional research and funding.
I interpret the linked post about receptivity to proposals to go vegetarian/vegan as providing evidence that people are receptive to these proposals. It states:
If the number of vegetarians is flat, yet people are abandoning the diet, this requires a constant inflow of new vegetarians to balance the outflow. The whole point of the post is that people are receptive to trying a vegetarian diet out, but that they struggle to maintain it long-term.
The claim in this post that "non-EAs are receptive to a proposal to substitute bivalves for other meat" does not provide any evidence in favor of the assertion, which might just be a missing link.
I think it's important to make this claim about receptivity to bivalve/meat substitutions more specific. Is this population of non-EAs members of the general public? What countries do they live in? How often, and how much, and for what kinds of meat would they consider bivalves an acceptable substitute? Will they pay more to substitute bivalves for other meats on a pound-for-pound basis, and if so, how much more?
Shellfish consumption tends to be aggregated with seafood consumption in general, but the USA consumes a moderate amount of seafood relative to other countries. It's not clear to me what you mean by the USA having "idiosyncratic food preferences." I was only able to find this data on American oyster consumption specifically. While low, I think this is better explained by a combination of the high cost of oysters and the fact that America has a great deal of non-coastal land a long tradition of ranching, and excellent farmland, making cheap, high-quality meat widely available to the population.
I suspect that meat freezes and ships much better than shellfish. I have no reticence about eating a steak from a cow slaughtered 2,000 miles away, but I think of "Midwestern sushi" as a rare example when combining a location name with a food name (i.e. "Washington cherries," "Argentinian french fries," "French pastry") as making the food sound worse rather than better.
I would want to see a deeper investigation into the tractability of upscaling shellfish aquaculture, a stronger argument on the market failure explanation for why normal market mechanisms are inadequate to motivate increased production, and better information on people's receptivity to bivalves as a meat substitute.
That said, I love oysters, and if we can altruistically make them cheap enough that I can eat them on the daily, that alone will make the EA movement a success as far as I am concerned.