It doesn't take a PhD to realize that the price of shrimp has fallen dramatically over the past several years, so fast, in fact, that shrimp consumption has doubled in the past decade. So why is shrimp so cheap?

Gourmet has a good piece on this in its March issue (sadly, not online) by Barry Estabrook, "Do I Dare Eat a Shrimp?" What the article makes clear is that there are truly bad choices, when it comes to these little crustaceans, and less bad ones, but what's not clear is whether there is really a good choice.

First, the bad. Shrimp farms have proliferated in the developing world, created largely by ripping out mangrove swamps and putting in shrimp ponds. These farms kill native fish and pollute surrounding waters, leading to more forest destruction. Like much of factory farming, they are particularly prone to pests and disease, so they become a dumping ground for more than 20 antibiotics and pesticides. One of the most potent, the antibiotic chloramphenicol, can be toxic to humans and is banned for use in the U.S. Plus, these shrimp eat fish protein, which can lead to depletion of feeder stocks (one of the hidden costs of fish farming in many species).

Not surprisingly, the article asserts these shrimp don't taste very good either.

On the back of these operations, the price of shrimp has fallen dramatically, putting trawlers in U.S. waters out of business. But even these operations, which are catching real and tasty shrimp, are not benign. The problem, as with much of the fishing the world, is by-catch (that is, all the stuff that is killed and thrown overboard to catch the fish you want). Used to be it took 10 pounds of by-catch to get one pound of shrimp; now larger-holed nets have reduced that ratio to two-to-one.

But the wild catch amounts to only 200 million pounds a year, compared with the 1.4 billion pounds Americans eat each year. So it looks like farmed shrimp is here to stay, so the question becomes whether it can be done sustainably.

One company in Florida, OceanBoy Farms, is trying with closed inland pens. It recycles its water, grows Talapia feedstock fish, which are vegetarian (a good choice for people too), and also feeds the shrimp organic soybeans for protein. It avoids antibiotics and chemicals by having a superclean, bio-secure environment. Now fish farmers the world over are visiting the operation, since it does not depend on ripping out forests.

Only problem: the shrimp taste okay, not great, and are more expensive than the competition. (Recall that the competition doesn't spend the money to do things right -- it simply rips out more forest).

So what's a consumer to do? The clear choice is to buy a product that can be as close to sustainable as possible, either wild or farm-raised. Right now, that choice usually leads to U.S. suppliers. Or you could choose to stop eating shrimp and make your little dent in the 1.4 billion pounds consumed. Personally, I think it makes more sense to support those trying to do things right and create an alternative.

Now, enjoy your shrimp cocktail.