THIS: Farmed Fish
Pros: Farmed fish are raised on land, usually in pools or tanks, but they can also be raised in offshore fish farms—areas of ocean that are netted off to keep the stock fish from escaping. The major plus of farmed fish is that they allow for a high yield of fish without the risk of overharvesting and depleting wild populations.
Cons: Although land-based fish farms tend to have a much lower impact on their surrounding environment than offshore farms, both types have been compared to concentrated animal-feeding operations (CAFOs): Thousands of fish are crammed into pens, which leads to the growth of diseases and parasites that require antibiotics and pesticides. With offshore farms, nitrogen and phosphorous from feed and waste lead to algae blooms that can contaminate surrounding water. On land-based farms, heavy rains and floods can cause nitrogen to run off into nearby waterways, although many land-based systems use recirculated water that has been treated to remove high levels of the chemicals. Also, food fed to farmed fish is partially composed of wild-caught fish that may be contaminated with chemicals such as PCBs and cancer-causing dioxin. Perhaps the biggest downside to offshore farms is that fish can escape and compete for food, or even breed with other wild fish, causing the eventual die-off of native species.
THAT: Wild Fish
Pros: Aside from chemicals like PCBs and dioxin, wild fish are free of all the problems listed above. (If you do it right, fly fishing for freshwater fish like trout can be especially sustainable.)
Cons: Overharvesting is a serious threat to many species of our favorite fish, such as bluefin tuna. Thanks to technology and improved gear, ocean fisherman have increased their catch 400 percent in the last 50 years, leading to the virtual collapse of some species, such as New England cod. In addition to that, the techniques used by ocean fisherman lead to the destruction of other ocean ecosystems and to unintended by-catch (other sea creatures caught and killed in the fishing process). For example, according to the Monterey Bay Aquarium, each pound of shrimp caught in a trawl net contains an average of two to ten pounds of other marine by-catch, which is usually discarded overboard.
This or That?
This. Or that. It depends. Like many environmental quandaries, the debate over wild vs. farmed fish doesn’t yield a simple, universal answer. Some fish species are in more danger in the wild than others. Some fish-farming operations are better and more responsibly managed than others, and the same can be true for wild fisheries. If you tend to eat one or two kinds of fish exclusively, check the list below to see which option is best for your favorite finny food. If you like to mix and match your seafood choices, you download the Monterey Bay Aquarium’s Seafood Watch guide to take with you when shopping or dining. Or use your mobile device to log on to mobile.seafoodwatch.org.
U.S. sturgeon caviar
Steamer, Littleneck, or Cockle clams
Alaskan salmon (avoid Atlantic salmon; it’s farmed in a destructive manner)
Dungeness or stone crab
Pacific cod (not New England cod)
Pacific halibut (Atlantic halibut is overfished and high in contaminants)
Shrimp (but farmed U.S. Pacific white shrimp, West Coast white shrimp, or ebi is OK; avoid imported farmed or wild black tiger shrimp, tiger prawn, white shrimp, and ebi)
Spiny lobster from Maine, Australia, and Mexico’s Pacific coast
White seabass (sometimes called “king croaker”)
Yellow perch (preferably from Lake Erie)
For the most ecofriendly fish, look for the Marine Stewardship Council label, which is applied to responsibly managed wild fisheries.