Similar to the not-so-helpful categories of "shrimp" versus "prawns," classification of shrimp according to their natural habitats (freshwater versus saltwater, warm water versus cold water, Asian versus South American) can also be confusing since so many of the shrimp we eat are not wild-caught but farmed.
During the first half of 2012, we imported over 525 million pounds of farmed shrimp into the U.S. from other countries. Nearly 25% came from coastal farms in Thailand, 18% from Ecuador, and 16% from Indonesia—meaning that almost 60% of all the farmed shrimp we ate came from shrimp farms in these three countries. Imports from India, Vietnam, China and Mexico combined for another 27%. By comparison, we produced less than 9 million pounds of shrimp during this same 6-month period inside of the U.S. So we imported nearly 60 times more than we produced, and the vast majority of it from seven countries.
In comparison to these hundreds of millions of pounds of globally farmed shrimp, only 2 million pounds were wild-caught along the coastlines of the world's countries. In other words, the native waters providing different species of shrimp with their original habitats did not play much of a role in our shrimp consumption, since so much of our shrimp came from man-made shrimp farms and since these farms did not necessarily raise shrimp that were native to the region.
A great example is Thailand—our primary source of shrimp. Today there are approximately 25,000 shrimp farms in Thailand. Nearly all the shrimp we import from Thailand are white shrimp (Litopenaeus vannamei, also known as Penaeus vannamei ) produced on these coastal farms. White shrimp are not native to Thailand. They are warm-water shrimp native to the Pacific Ocean from the west coast of Mexico down to the coast of Peru. Only 10 years ago, however, nearly all of the shrimp that we imported from Thailand were farmed tiger shrimp (Penaeus monodon) native to this Asia region. But a switch from production of tiger shrimp to white shrimp was made for reasons like ease of production and better rate of growth. (Based on a law passed by the U.S. Congress in 1989, the importing of wild-caught shrimp from Thailand was banned in the U.S. due to use of shrimp trawlers that lack turtle excluder devices, also known as TEDs.)
Since the shrimp we import from Ecuador are also farmed white shrimp (Litopenaeus vannamei), as are the shrimp that we import from China and a significant percent of the shrimp we import from Indonesia, you can see how farmed white shrimp have become the most commonly consumed type in the U.S. In fact, we eat relatively few shrimp in the U.S. that are not either farmed white shrimp from these countries or farmed tiger shrimp imported from countries like India, Malaysia, or Australia. So can see how there has become very little relationship between the natural habitat of this shellfish and its role in our food supply. In addition, it is also important to note that the creation of many shrimp ponds throughout the world has required the cutting down of mangrove forests. Without these mangrove forests to protect shorelines and to provide a home for other plants and animals, the regions involved have tended to suffer from unwanted environmental imbalances.
If you want to enjoy shrimp in your meal plan, yet are concerned about the consequences of shrimp farming for natural habitats, one option is to purchase only wild-caught shrimp. If you're further wanting to choose wild-caught shrimp from a particular region where shrimp stock are in less jeopardy, you can also take advantage of shrimp labeling. Since 2005, it's been possible to determine the country-of-origin for shrimp since shellfish (and fish in general) were the first foods to have required country-of-origin labeling (COOL) in the U.S. marketplace.