Native fish species caught as whitebait
The fish caught as whitebait are a mixture of these species:
Īnanga are the most common species in a catch, making up about 85% of the total number of fish. Kōaro and banded kōkopu are the next most common, with each species making up about 5-10% of a catch. Giant kōkopu, shortjaw kōkopu and common smelt/paraki are the rarest species – together they make up less than 1% of a catch.
This mixture of species can vary around the country and at different times during the whitebait fishing season. Sometimes other species like eels are caught too.
Whitebait are threatened with extinction
All six species caught as whitebait are threatened or at risk of extinction. Their populations are declining because:
- large areas of wetlands have been drained
- vegetation like grasses and trees beside streams has been cleared
- fine silt or sediment washed downstream clogs up streambeds
- structures like dams and overhanging culverts stop whitebait from moving upstream
- pollution from land, like farm runoff, carries contaminants that are harmful to all stream life
- weeds choke streams and wetlands.
Whitebait are migratory galaxiids
The scientific names for many of New Zealand’s native fish and all the whitebait species start with ‘Galaxias’. For example, inanga are called Galaxias maculatus. This name and their family name ‘galaxiid’ comes from the patterns on the skin of adult fish that look like a galaxy of stars.
The whitebait species are known as migratory galaxiids as they all migrate upstream from the sea into freshwater as young fish. This is when some are caught as whitebait.
New Zealand’s non-migratory galaxiids stay in freshwater streams and rivers all their lives.
Galaxiids are found in many places in the Southern Hemisphere, but banded, giant and shortjaw kōkopu only exist in New Zealand. Our galaxiids are generally nocturnal and very good at hiding. They find shelter and food in streams, rivers and lakes in lowland areas near the coast.
Whitebait lifecycle
Migratory galaxiids all have a similar lifecycle, and spend time in freshwater as well as the ocean. Their lifecycle follows these stages:
- adults release eggs and milt (sperm)
- eggs are laid and fertilised in vegetation beside streams and rivers
- eggs hatch and larvae are washed downstream into the ocean
- larvae grow into juvenile fish and migrate from the sea upstream in the spring
- juvenile fish grow into adults.
Whitebait species lifecycle
Image: DOC