There are dozens of shrimp species that are farmed or caught in a variety of ways and places, leading to large variation in the sustainability of shrimp products. There are two main types of shrimp: warm-water and cold-water. Warm-water can be farmed or wild. Cold water is always wild. By far the most common shrimp in restaurants is warm water, i.e. tiger, white, jumbo, or rock shrimp, and this is the hardest kind to get from a sustainable source.
Almost all cold-water shrimp, i.e., salad, northern or pink shrimp, is considered sustainable. They can be sourced from northern California, Oregon or British Columbia. They are trawled in open waters where bycatch and trawl damage are minimal. We are fortunate here in Santa Barbara that our locally caught ridgeback shrimpand spot prawns are incredibly tasty and harvested sustainably. They are available fresh October through May.
The only acceptable source of warm-water shrimp in our program comes from the U.S., primarily found in the Gulf states. However, warm-water shrimp, whether fished or farmed is generally either not eco-friendly or is energy/resource intensive, so we discourage the use of these products.
Why is warm-water shrimp so unsustainable?
Wild warm-water shrimp is caught in bays and estuaries with small-mesh nets dragged along the sea floor. These trawl nets haul up anything in their path, including the bottom habitat itself, like corals, sponges, and algae. There are two main problems with this fishing method: It is inefficient.
- On average, ten pounds of sea life are discarded dead as‘bycatch’ for every pound of shrimp taken. Many of these animals are sensitive to extinction – turtles, corals, juvenile snappers and many more. In some areas, trawl nets also inadvertently catch and drown marine mammals such as dolphins.
- It destroys the sea floor. Trawl gear bulldozes the habitat so that fish and other sea life can no longer flourish in the area.
Recent technological fixes to address these problems include lighter trawl gear that elevates the net instead of scraping along the bottom, escape hatches in the nets for turtles, and required on-board GPS systems to enforce no-trawl zones where dolphins congregate. Even with these preventative measures high levels of bycatch are still a big problem.
The U.S. has the best adoption and enforcement of these improvements. However, wild
U.S. shrimp mostly comes from the Gulf and it can be cost-prohibitive to truck shrimp from the Gulf. Unfortunately, no other country exports wild shrimp harvested with improved fishing methods, so imported wild warm-water shrimp is not acceptable.
Farming shrimp can either be done cleanly or with major destruction and pollution, which means you have to buy your farmed shrimp carefully if you want to serve it. U.S. farmed or “closed-system” shrimp is the only trustworthy eco-friendly source we recommend. About 75% of farmed shrimp is tiger prawn produced in Asia, in particular in China and Thailand. The other 25% is mainly Pacific white shrimp from Latin America. Mexico is a major source of farmed shrimp for California markets.
Most farmed warm-water shrimp are considered unsustainable because they:
- Are farmed in warm coastal areas where mangrove forests are cleared to make shrimp ponds. Mangroves are a critical nursery habitat for many ocean fishesand provide protection from flooding. They also sustain coastal communities asa source for forage food. Over half the mangrove forests of the world have beenremoved, mostly for shrimp farms and tourist development. Building a shrimp farmmight bring in $4,000 an acre, but it will destroy natural resources that have beenestimated by the World Resources Institute to be worth $20,000.
- Use high concentrations of chemical antibiotics, pesticides and fertilizers because the shrimp are grown in high density monocultures where disease outbreaks are rampant. For instance, formaldehyde, a carcinogen, is widely used as a pesticide in both in U.S. and foreign shrimp farms and remains in the shrimp when eaten. The high amounts of chemicals used in shrimp pond operations cause the ponds to accumulate a toxic sludge which is either dumped into the adjacent bay or the entire pond is abandoned to become a wasteland. New areas are cleared of mangroves and the cycle continues.
- Contribute to the rise of antibiotic resistant bacteria worldwide. Some of these chemicals are banned in the U.S., but it is not illegal to import shrimp grown with them. The chemicals remain in the shrimp even when cooked and can pose serious threats to diners. In one study, shrimp cooked for 30 minutes at 212º F still retained 71 percent of the antibiotic chloramphenicol (so toxic it is not recommended for use in humans). The FDA has sometimes rejected shrimp imports because of unsafe drug residues, as well as high salmonella loads, but monitoring and enforcement are at an all time low.
- Child labor is often used. Fair treatment of workers is also a perennial issue in the shrimp farming industry.