Meet the Whitebait | Conservation blog

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Source: Department of Conservation

Freshwater Ranger Suze Harris is based in Hokitika and studies migratory galaxiids on the West Coast. Here she explains a summary of what whitebait grow up into, and what habitats you can find them in.

There are 5 whitebait species in the Galaxiidae family (excluding smelt/cucumber fish, which are not a true galaxiid). Each have their own habitat preferences and unique behaviours! They do not have scales and tend to be nocturnal to feed on aquatic and terrestrial invertebrates while avoiding predation by bigger fish.

Īnanga (Galaxias maculatus)

Image supplied by: Suze Harris. Image credit: Angus McIntosh

The most famous of the whitebait species, making up 90% of any whitebait fritter (depending on the river). Highly fecund (produce a lot of eggs) and live close to the coast. They are weak swimmers and cannot climb, so they stick to slow-moving waters such as wetlands, swamps and lowland streams. Their greatest threats are fish passage barriers (such as overhanging, perched culverts or structures with high velocities running through them), habitat loss, and introduced species. Īnanga spawn in autumn on spring tides on the sides of creeks and rivers. Generally, they live 1-2 years, some spawn twice. Like the rest of the whitebait species, they can live a lot longer in captivity.

Giant kōkopu (Galaxias argentus)

Image supplied by: Suze Harris. Image credit: Angus McIntosh

Giants are the largest of the whitebait species, with the record length being 450mm, and were the first Galaxiidae to be described in 1789. The golden spots are very distinctive, and its colour pattern inspired the generic name of Galaxias to the whitebait family – referring to the profusion of stars in the galaxy. They are territorial in nature, usually lurking in slow-flowing waters in lowland runs and pools, and feast on large insects like cicadas and wēta. Their spawning ecology is still being unravelled by ecologists, a recent study suggests there are freshwater migrations to and from their domain to spawn.

Eggs are deposited in floods during autumn on the banks of dense canopy cover. They usually run later in the whitebait season. Because they require instream cover with overhanging vegetation, they are disappearing from the east coasts of both islands. Some can live beyond 20 years, up to 40 years in captivity.

Banded kōkopu (Galaxias fasciatus)

Image supplied by: Suze Harris. Image credit: Alfonso Siciliano

Bandeds are common throughout the coast, and are the smallest in the whitebait stage, often golden in colour. They are difficult to differentiate from the other kōkopu when they are young, but the key feature in larger fish are stripes connect over their backs, which is easiest to see towards their tail. They rely on terrestrial insects and are sensitive to intensive land development and sedimentation, hence why they are less common on the east coasts of both islands. They are happy in any type of forests, including pine, beech, and rainforests.

Shortjaw kōkopu (Galaxias postvectis)

Image supplied by: Suze Harris. Image credit: Angus McIntosh

The rarest of the whitebait species, shortjaws are named due to their overbite. They do not have distinct markings other than a black patch behind their gill plate, a blue-green eye, and a dark fringe on their fins. Territorial in nature, they like rocky streams with stable pools to live out their adult lives, likely ranging between 7-15 years. Little is known about these fish due to their solitary nature, but like the other kōkopu species, they spawn in autumn floods on the banks of streams, eggs develop in moist leaf litter and get carried away by floods out to sea. They tend to not coincide with beech forests, so are very rare south of Ōkārito.

Smoothwater River is the furthest southern record on the West Coast, and none have ever been recorded in Fiordland. They are now thought to be extinct from Canterbury. The West Coast is the densest area for shortjaws nationally due to habitat availability and decent water quality.

Kōaro (Galaxias brevipinnis)

Image supplied by: Suze Harris. Image credit: Angus McIntosh

Also called climbing galaxias, Kōaro are the best climbers of the galaxiid family. They have elongated bodies with similar golden markings to a leopard. Their enlarged pectoral fins are ribbed, helping them climb any wet vertical surface. They can be found at the headwaters of rivers such as the Arahura and the Haast, even in the heart of the Southern Alps, which makes their larval migration out to sea incredible. There are lake-locked populations in NZ, including Lake Wānaka. They like rocky, tumbling streams and can be seen “moon bathing” on top of wet rocks in streams at night, which is likely a tactic to avoid tuna (eel) predation.

Whitebait season

Remember if you’re unsure of what the whitebait fishing regs are or would like to know more about the whitebait fishery go to our DOC website Whitebaiting: Things to do (doc.govt.nz). If you’re wanting to speak to one of our local rangers, please contact your local DOC office for more information or email whitebait@doc.govt.nz

MIL OSI

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