# How feasible would a civilization of carnivorous organisms that subsist off fish farming be?

I have a race of sentient amphibian humanoids that live on a very hot and humid planet that has massive amounts of large lakes, ponds, and rivers. They are carnivorous and for simplicity they have a similar caloric intake to humans, and for domestic fish species imagine fish like what we have on Earth. So fish like salmon, trout, tuna, etc. They posses the knowledge and ability to farm so that they can feed the fish.

Would it be plausible that a society of these amphibious humanoids could subsist of fish farming?

• We ourserlves are sentient and subsist on farmed calories... And "as of 2016, more than 50% of seafood was produced by aquaculture" (Wikipedia). Apr 21, 2017 at 18:51
• I mean... this seems like a pretty easy calculation for you to do with IRL numbers. Find out: how many fish per cubic yard of water become harvestable per month, how many cubic yards of water, how long it takes for a fish to mature, and how many calories per fish. Put in some amount of loss (fish mangled in nets, lost overboard, whatever), then you know how many calories are produced for a farm. That number gives you how many "people" can be supported by that farm. Apr 21, 2017 at 19:17

Yes, but not to the same extent as an omnivore or herbivore.

The population density of any carnivorous species must be lower. Or else the food production must be much more efficient than on earth. It takes more energy input per meat calorie than per plant calorie.

So either imagine a way in which your lakes produce meat calories more efficiently. (The planet is volcanically active and the large number of heat vents in the lakes provides another energy source for meat calories).

Or simply let the world population be less dense.

Here is a good question to compare to.

Food economy of pre-civilization carnivorous humanoids

• Thank you, I was 90% sure that it could work, but I wanted to make sure I wasn't missing something major that somebody would point out. Apr 21, 2017 at 20:14