New Zealand has three species of so-called freshwater crayfish, which, since they have powerful pincers, have more the appearance of lobsters.
They are found in most districts in small streams, lakes, and ponds. At Rotorua the Maoris fish for these crayfish by lowering small bushes to the bottom of the lake. The crayfish shelter underneath from the light, and as the Maori fisherman slowly hauls the bush to the surface the crayfish come up with it. These crayfish are about 5 in. in length and are of dull greenish colour. Just prior to moulting, crayfish form a dome-shaped limy body internally. This acts as a reservoir of lime to be dissolved and later used in the formation of a new shell.
by Arthur William Baden Powell, Assistant Director, Auckland Institute and Museum.