Whitebaiters call smelt 'cucumber fish' because they smell like cucumber.
The small shimmering silver fish occur in large shoals in estuaries and lowland rivers. They spend most of their lives at sea. Some return to freshwater as juveniles in spring but most return as adults in summer when they are about 10 cm long. They can also be found in some lakes.
There are two species – the common smelt is found throughout the country, and Stokell's smelt is found only in Canterbury.