Aquaculture Home

Wild Fish

Pollution & Disease


Habitat Damage


A Bountiful Harvest Still Depends On the Sea

While farmed fish and shellfish can supplement our seafood supply, they can't replace the variety and abundance of seafood from the wild. Some fish farms still depend on wild populations to supply eggs or young that the farmers raise for market. Many fish farms also depend on wild fish, like anchovies, as food for the farmed species.

Some Fish Are Carnivores

Every year, millions of tons of wild fish like sardines and anchovies are caught and processed into fishmeal and fish oil for farm-raised species. Salmon—one of the most popular farmed species in the world—is a carnivore, eating well over a pound of wild fish for every pound of weight it gains. Tuna takes over 15 pounds of feed for every pound it gains.

Developing Alternative Diets

There's good news: not all fish are carnivores. Some fish, like catfish and tilapia, can be raised on diets with very little or no fishmeal or fish oil. These alternative feeds take pressure off wild fish populations. They're good for fish farmers, too, costing far less than fish products. Shellfish (like mussels and oysters) are another good option. These animals feed by filtering particles out of the water and can be easily farmed in clean water where they collect their own food and don't require supplemental food.

Ranching Wild Fish

In a recent trend, fish farmers have become "ranchers." Instead of raising fish from eggs, they take large numbers of small, young fish from the wild and grow them for eventual sale. In one instance, young eels are caught and then farmed to supply unagi to sushi bars, a practice that has led to depleted wild stocks. Young bluefin tuna are also being caught and ranched in operations that are both highly profitable and resource intensive—further impacting depleted populations.

What You Can Do

Search for Sustainable Seafood 

Farmed oysters, clams and mussels are an excellent choice. Most oysters on the U.S. market, and many clams and mussels, are farm-raised. These shellfish filter tiny plankton out of the water and need no supplemental feeding. They can even improve water quality!

Support Our Restaurant Partners

Please consider dining with one of our restaurant partners! These restaurants in California and throughout North America no longer serve items from our red "Avoid" list. They also train their staff members, and help raise awareness in their communities.


Story of Hope

Innovations in Aquaculture Feeds

One of the biggest issues facing aquaculture is its dependence on wild fisheries for fishmeal and fish oil, which are used to feed many farmed species. The high cost of fishmeal and fish oil—as well as their limited availability—is encouraging the development of alternative feeds. Potential alternatives being tested or in use include soy, grains, other plant proteins, single-cell proteins, algae and byproducts from seafood and livestock processing. Many of the major feed manufacturers are investing heavily in development of these products.
Learn about wild seafood Related ocean issue resources