As Paul Greenberg points out in his new book, "American Catch: The Fight for Our Local Seafood," Americans used to be awfully fond of oysters. In the mid-1800s, he writes, "eating three or four dozen at a sitting was the norm." But pollution wiped out the practice. Greenberg reports that within a few decades, New York City's waterways were taking in 600 million gallons of raw sewage each day.

Eaters eventually shifted their affections to shrimp, which has been commercially farmed since the 1970s. By weight, Americans today eat more shrimp than tuna and salmon combined. The vast majority of those 1.2 billion pounds come from foreign farms, many of which are associated with serious environmental degradation, labor abuses and tainted products. According to Greenberg, 10 percent of imported shrimp tested in a 2012 study had residue of antibiotics banned in the U.S.

One alternative is wild-caught U.S. shrimp. There are two shrimp seasons in South Carolina: The brown shrimp season, which typically runs from June to August, and the white shrimp season, which extends from August through December (Pink shrimp, the third of the state's important edible species, isn't sufficiently abundant to command a commercial season.) That makes late summer the perfect time to shun farmed shrimp from China, Thailand, Vietnam, India, Indonesia and Ecuador. Here's what else you need to know before reaching for your deveining knife:

1. Shrimp are sorted by size, ranging from miniature to colossal. The terms refer to how many shrimp are in a pound: Miniature shrimp run about 100 shrimp to a pound, while colossal shrimp are 10 times as large. Colossal and jumbo shrimp are sometimes listed on restaurant menus as prawns, probably because the seemingly oxymoronic phrase "jumbo shrimp" has become a punchline, but the term has no scientific standing.

2. Crustacean shellfish, such as lobster, crab and shrimp, are classified by the U.S. Centers for Disease Control as one of eight major food allergens. The culprit is a protein that also occurs in less-tasty invertebrates, which is why shrimp allergy sufferers may also struggle with exposure to cockroaches or dust mites.

3. When shopping for shrimp, seek out firm shrimp free of black spots, which mean the meat is starting to go bad. The shrimp should smell like saltwater; an ammonia aroma also is indicative of deterioration. Outside of local shrimp season, frozen shrimp are generally preferable to "fresh" shrimp, which may have been thawed for their appearance in the fishmonger's case.

4. The reddish color of shrimp comes from astaxanthin, a pigment that functions as an anti-inflammatory and antioxidant. Shrimp also are rich in protein, Omega-3 fatty acids and B vitamins.

5. "Some experts" claim that white shrimp are the best-tasting of the world's 3,000 wild shrimp species, according to the clearly skeptical S.C. Department of Natural Resources. "Longtime residents of the Lowcountry may state that they prefer the flavor of one species over another, but taste tests would probably show that few people can distinguish one species from another by taste alone," the agency's website asserts.

6. Most Tibetan Buddhists eat meat, largely because vegetables don't thrive in the Himalayas. (Citing doctor's orders, the Dalai Lama refused to adopt a vegetarian diet even after Paul McCartney implored him to do so.) But they generally avoid shrimp, because it takes so many creatures to make a meal. Shrimp are forbidden by Jewish dietary codes, which restrict seafood consumption of fish with fins and scales. According to, the prohibition is considered a chok, or a decree beyond comprehension.

7. Deveining a shrimp doesn't remove a vein: It strips the shrimp of its digestive tract. Because the idea of gobbling down the organ responsible for processing a lifetime's worth of worms, crabs, nematodes and shrimp (shrimp are known cannibals) gives some eaters the willies, they insist on pulling out the intestine before cooking. But the dark-colored strand is edible and nutritious. In 1982, a reader of Craig Claiborne's syndicated column asked if deveining was necessary, inadvertently sending the Mississippi Delta native into a Southern shrimp reverie: "When I was a child in the South, we often dined on shrimp that were cooked and served piping hot in the shell, each guest helping himself or herself to the melted butter and lemon juice with Worcestershire sauce and a touch of Tabasco. No one ever bothered to devein the shrimp before swallowing them."