SHRIMPS
Shrimps are shellfish of the crustacean family that also includes lobsters, crayfish, and crabs. They all have in common the strong shell body, the muscular tail section (except crab) that we eat, and the forward part of the body that contains the eyes, digestion and reproduction organs. What separates shrimps from other crustaceans is that their forwardmost pair of legs is not transformed into claws. Shrimps have then five pairs of walking legs attached to its frontal part of the body, and five pairs of swimming legs at the tail (actually the abdomen). Shrimps are probably the easiest shellfish to catch since they grow up quickly and they eat various kinds of things. Also, one female normally produces up to 1 million eggs, so their reproductive capacity is enormous. Another kind of shrimp, called prawn, is simply a larger sort of shrimp, and there are a few hundred species of this animal available for catching. The most common variety though is the Penaeus shrimp that grows to its full size within a year and can be 25 cm/10 in long.
See a video of a live tiger shrimp here:
http://www.youtube.com/watch?v=0aUwIPKFiOk
Shrimps, like the other crustaceans, must frequently change its shell for a new one - a process called molting. This is accomplished by the animal building up a layer of a new shell beneath the old one, after shrinking its size to shrug off the unwanted exoskeleton. Then the shrimp is inhaling lots of water to stretch out the new shell and simultaneously mineralizes it with calcium. During this process, the crustacean animals are not so tasty and obviously heavy on water. Shrimp can grow very quickly, over 5 cm/2 in per month, and this is one reason they need to go through molting of the exoskeleton many times during their lives. Most frequent molting happens when the shrimp is young and grows faster than the older specimen. Young shrimps may molt several times per week. A normal life span of a shrimp is 8-9 months.
The harvest of shrimps is done by trawlers and they usually work in three seasons during the year. In May and June the season starts after enough shrimps have been spawned, which highly depends on the preceding winter conditions - mild winters are better for a great harvest while cold winters may severely reduce the quantity of shrimps. In the summer months, brown shrimps can be harvested, and they usually come in high quantities. Lastly, in the fall, white shrimps are harvested and they are usually in the highest number of all harvests (unless the winter hasn't been too cold, that is). Observe that these seasons may not be the same in the places where you live, and other types of shrimps may be caught during other times of the year.
When you are buying shrimps do so from a reputable vendor. The shell should look clean without any spots (sign of decline) and they should smell like seawater, not like rotten fish or worse. Always smell the shrimps before you pay for them! Shrimps are usually sold either fresh or frozen. Even though the latter have a longer storage life (a week or so) the fresh ones taste better. The 'trick' is to cook the shrimps right away and don't store them for another day, since their flavor disappears very fast. Usually the tail muscle is eaten, either cooked or raw, and it is easily separated from the shell by simply peeling it off. It is also good to remove the dark 'vein' that runs along the tail muscle (it is actually the intestine of the shrimp). So, a quick cooking of the entire shrimp in water and then peeling off the shell and eating the tail muscle is the way to go with shrimps. Just don't cook for too long, because the meat will become rubbery. Normally, people just throw the shrimps into simmering water and wait until they come up to the surface and float (their color becomes pink as well). Then they are plunged into cold water to stop cooking.
Shrimps are good with bacon, butter, chiles, chives, chervil, garlic, lemon, white wine, shallots, or other onions. On the more exotic side you can add some mangoes, mint, pineapple, or serve the shrimps with caviar.