Freshwater invertebrates

New Zealand’s streams are home to hundreds of tiny animals that live on and under rocks, waterplants, wood or debris. These animals include insects, crustaceans such as freshwater crayfish (koura), molluscs such as snails and mussels, worms and leeches. They range in size from less than 1 mm long to over 10 cm long and can often be hard to see at first glance. Together these types of animals are called ‘macroinvertebrates’, meaning they have no backbones and can be seen without a magnifying glass or microscope.