Crustaceans
Crustaceans are the most valuable group of marine organism. They form about 4% of the total world catch. Almost all species in this group are considered on the world market as high value commodities.
The most important group are shrimps or prawns. The two names refer to the same group which on is used depends upon local preferences.
Shrimp are distributed all over the world. From the commercial point of view, they can divided into cold, warm and freshwater species.
Coldwater species, e.g. Pandalus borealis and Crangon crangon, grow slowly and are small in size, compared to warmwater species, mainly of the Penaeus family which grow quickly, reaching a large size.
Freshwater species, mainly Macrobranchium rosenbergii, inhabit tropical lakes and rivers, growing very fats and reaching a very large size up to 0.3 kg.
For that reason shrimps of Penaeus and Macrobranchium families are now successfully cultured.
Tropical marines species are the most important part of world trade in crustaceans with main markets in the US and Japan.
Cold water species are preferred in Europe.
Due to high commercial value, processing and trading of shrimp are highly specialized. Shrimp are sold alive, fresh, frozen, canned, dried and in a number of different forms, e.g. whole, headless, shell-on, peeled, peeled and deveined, etc.
There is precise grading by size systems, i.e. numbers per 1 kg or 1 lb, different in the US and Japan.
Another important and valuable group of Crustacea is the crab. Caught usually by traps they form a base for the canning industry, particularly in the US, the USSR and Japan.
Crabs are also sold fresh an frozen. Of all crabs, Pacific snow crabs Chionoecetes spp. and king crabs Paralithodes spp, are the most important species.
Lobsters are considered a delicacy all over the world and are this highly priced. Due to their edible, lobsters are sold unprocessed, commonly alive, but as a majority fresh or frozen. There are many different species of lobsters of which spine lobsters Panulirus spp, rock lobsters Jasus spp., American lobster Homarus americanus, and European lobsters H. gammarus are the most important ones.
Coldwater lobsters of Homarus spp, differ significantly in shape from the first ones inhabiting warm waters. The Homarus spp. have strong claws and can reach the size of a few kilograms.
There re also vast quantities of small pelagic crustacea Euphausidacea of which Antarctic krill Euphausia superba form the largest concentrations, thus enabling efficient catches.
Crustaceans
