The fisheries are important, principally those for shrimps and lobsters.
The name of shrimps is sometimes given to members of the order Schizopoda, which differ from most of the Macrura in having swimming branches or exopodites on the thoracic legs.
The shrimps and their allies are distinguished from the larger Macrura, such as the lobsters and crayfishes, by greater development of the paddle-like limbs of the abdomen or tail, which are used in swimming.
It is now known to consist of the young fry of herrings and sprats in varying proportions mixed with a few shrimps, gobies, sticklebacks, pope-fishes and young flounders: but these impurities are as far as possible picked out from the whitebait before it is marketed.
Shrimps (kawa-ebi) also are found in the rivers and rice-fields.