1. Pacu. A peace-loving and eminently edible relative of the piranha, pacu are native to the Amazon.
They take high temperatures, low oxygen, and crowding in stride (try living the Amazon if you can’t…). Cons: I’m pretty sure there isn’t seedstock available in the US. We’d have to import it, with all the attendant precautions to make sure it doesn’t escape. We’d like to explore these someday but we haven’t the wherewithal to start importing and breeding new species at the moment.
2. Jade and silver perch (grunters). Pros: these fat little buggers come to us from the billabongs of Australia where they have to cope with unpredictable habitat and food availability thanks to Australia’s schizophrenic rain schedule. Tilapia deal with their own feast-or-famine environment by breeding their brains out whenever the breeding is reasonably good. Grunters deal with it by larding up until conditions are totally perfect. Silver perch has about the same amount as salmon and jade perch has about three times as much in their mild white meat. Cons: Not available yet in the US; would have to be careful not to let them get out. They’re not as “breed-at-the-drop-of-a-hat” as tilapia but could still pose a problem in wild areas if they escaped.
3. Redclaw crayfish, another Australian species. Pros: most crayfish are cranky and cannibalistic– they don’t do farm life very well. But redclaws come from shrinkage-prone seasonal pools where they had to learn to live together in peace ‘n’ love. They’re tasty, gorgeous-looking, grow up to a voluptuous size that suggests “mini lobster” more than “crayfish,” and there’s even a breeder about 90 minutes away from us. We’ll probably grow at least a few of these during our trial scale. Cons: Put up some steep smooth sides on their tanks or they’ll wander out. The local raccoons would love you forever but it’s hard to make a living that way.
4. Sturgeon. Pros: They don’t need their water to be as cold as you’d think; their meat is AMAZING and cooks up very similar to swordfish; and also, caviar. They need a high-protein and fat diet but compensate for it by growing crazy fast. Wild sturgeon are going extinct from caviar poaching and international trade laws– the same ones that banned the ivory trade– aren’t stopping the black market. It’s not just sturgeon in the traditional Caspian Sea caviar fishery that are at risk, either– poachers have been starting to go after North American sturgeon as well. Our sturgeon stocks are still reeling from a little-known caviar fishing boom back in the 1800s, so they’re not in a position to take more pushing around.
Cons: Mainly regulatory challenges– the laws that restrict imports of caviar from the Caspian Sea have also basically inadvertantly outlawed the farming of beluga, the most endangered species. (Oops.) Conservation groups are also trying to extend that same protection to other sturgeon species which will make farmed caviar production in the US even more difficult. More on this later. People have only been doing endangered species conservation for maybe 40-50 years so it makes sense that there would be some beginner’s screwups like this.