Hacker News Reader

Comment by outworlder | Hacker News Reader

How feasible is it to grow crabs in captivity? We need to start farming food, no way natural ecosystems can support themselves _and_ humans at current levels.

View on HN

It's possible.

Searching suggests it is done more in SE Asia than in the US (this might be a "what does the cuisine focus on?")

RAS Vertical Farming for Mud Crabs - https://youtu.be/XQJmZz4mdWY (there's a bit of an accent, I'd recommend subtitles)

I'll also suggest a watch of How America's Biggest Indoor Shrimp Farm Sells 2 Million Shrimp Every Year - https://youtu.be/1AK_RQ1uaGs (the American diet tends to have more shrimp than crab). And for crawfish (not indoor) https://youtu.be/_bggaA5AURA

oh man, that mud crab video is wild!

Looked into this more.

"in aquaculture farms, post-nursery crabs reach marketable size and maturity in 6–7 months compared with 18–24 months under natural conditions"

Interestingly, raising animals in captivity is much much more difficult than I imagined.

IIRC - Guns, Germs, and Steel had a pretty good point that we didn't so much domesticate animals and plants as there were plants and animals that were pre-disposed to domestication.

Yeah for sure. Lion could well be 10x more delicious than beef for all I know, but I'm quite certain we couldn't farm millions of lions.

Meat from carnivores tends to not be very good/tasty for a variety of reasons. iirc most of it is mainly due to the fact that other carnivores process meat similarly to how humans do so it's not as nutritious/tasty. Also many carnivores tend to also kind of be scavengers whose meat is generally quite quite bad.

It's a common trope to state bad input taints meat taste but I think it's unproven. I think it's more likely that apex diet concentration of complex organic molecules causes taste differences.

Feed pigs on acorns exclusively, yes you get a specific ?malic? Acid outcome in fat.

Feed sheep on seaweed, same with iodine. Corn vs grass fed beef, same.

But "predators eat trashy meat so their flesh is trashy" doesn't ring true. "Obligate carnivore predators in the feline family process meat differently, and emit proteins into their own flesh" may be a mouthful but it's where I am.

Think swordfish and mercury

I did a decent amount of research into this a while back. They (blue crabs) can be grown in captivity, but they’re cannabalistic, so they have to be kept apart from each other. This makes it pretty inefficient and high overhead. The crab farming operations I’ve seen literally have each crab in its own little compartment - this is too labor intensive to be feasible outside of places with very low wages like the Philippines and Indonesia.

If someone can figure out how to keep crabs in large pens without them eating each other, they will make a lot of money. I’m not sure if that’s possible with selective breeding. Maybe we need to wait until crab legs can be “printed” or grown in a lab

> but they’re cannabalistic

Seems like a place where GMO organisms might make sense. You just have to knock out this behavior somehow.

would it be simpler just to de-claw the crabs so that they are unable to poke / snip at each other?

Claws have some of the best meat, if anything you want larger claws

But maybe just the pointy, immobile part of the crab claw would need to be removed. That usually doesn’t have too much meat.

Put a rubber band on the claws. Like they do in the tanks at red lobster.

No idea, but I see more plant-based food in our future generally. It's gotta be way, way cheaper to farm crops than fauna and farm-raised seafood comes with it's own issues with mercury, etc.

Reply on news.ycombinator.com