Whitebait is a collective term for the immature fry of fish, typically between 1 and 2 inches (25 and 50 mm) long. Such young fish often travel together in schools along the coast, and move into estuaries and sometimes up rivers where they can be easily caught with fine meshed fishing nets. Whitebaiting is the activity of catching whitebait. As whitebait consists of immature fry of many important food species (such as herring, sprat, sardines, mackerel, bass and many others) it is not an ecologically viable foodstuff and in several countries strict controls on harvesting exist.