Are sardines farmed?

Question

I've been trying to find out if sardines are farmed or if they are all wild and are only fished.

Most of the sources I find, like this page, say that they cannot be farmed:

They are not farmed, as the life cycle of the sardine does not lend itself to farming. Maybe in years to come some scientist may crack the sardine code, but not yet.

Even though a lot of sources say they cannot be farmed, there is the occasional mentioning that they are farmed, like for example:

When buying sardines we recommend you purchase the sardines that are wild caught, not farmed. Farmed sardines as well as many of the sources of fish have elevated mercury and other undesireable proteins from their food source. Sometimes in farm raised sardines the food source is chopped up meat from other fish that are high in mercury. Sardines would never have the chance to eat these large fish in the wild. Also, some fish farms feed their fish feces, other animal proteins, and foods that sardines were not designed to eat. So stick with the wild caught sardines.

After all the reading I've done, I've kind of arrived at the conclusion that most of sardines you find are fished from the wild, but there are also some that are farm raised. Is this correct? Are they farmed or not? If they are, is there any data on how much is farmed compared to how much is fished from the wild?

Answer 1

Like most saltwater species, sardines are not farmed in any significant number. Marine fishes accounted for only 2.8 percent of the world aquaculture production tonnage in 2017, according to this report from the Food and Agriculture Organization of the United Nations. In practice, wild-caught sardines are often ground up and used as fish meal for larger fish in aquaculture farms.

After the Pacific sardine population collapsed off the coast of California in the 1940s, an entire organization -- CalCOFI (California Cooperative Oceanic Fisheries Investigations) -- was created to study the issue and it still continues to monitor the coastal ecosystem. The challenge in growing sardines is that they are quite sensitive to environmental conditions; sardines feed on plankton, the primary source of food in the ocean, and plankton growth varies with sunlight, temperature, availability of chemical nutrients in the water, and other factors. Sardine aquaculture would have to master the production and dissemination of the necessary volume of plankton within the saltwater environment where you'd be raising your crop of sardines.

In the open ocean, sardine populations migrate along with their food supply, or fail to reproduce where conditions are poor. Every so often fishery managers shut down sardine harvesting when the population crashes.