Fish to Pellets to Fish Again
After turning small wild fish into meal, fish feed processors mix in vitamins, minerals, cellulose, lipids, and other ingredients, and mold the mixture into pellets. Later, aquaculture operators feed the pellets to farmed finfish.
How many pounds of wild fish does it take to get one pound of farmed fish? About five pounds of small fish produce one pound of dry fishmeal or fish oil, which in turn makes up about 40 percent of the feed for marine finfish. The fish, on average, gain one pound for every two pounds of pellets that they eat, until they reach market size and become food for humans.116 Thus, every two to six pounds of fish caught in the wild yield one pound of fish raised in a cage.
The Wild Fish to Farmed Fish Conversion117
(Under laboratory conditions, with fishmeal as the source of protein in feed)
| Fish | Pounds of wild fish used to produce one pound of farmed fish |
|---|---|
| Cobia118 | 3.27-6.72 |
| Red porgy119 | 4.64 |
| Red drum120 | 3.71-5.56 |
| Atlantic halibut121 | 2.74-3.17 |
| Atlantic cod122 | 2.81-3.07 |