One of New Zealand’s largest populations of Upland long-jaw galaxias Galaxias prognathus ‘aff. Waitaki’ is found in the project area at Fork Stream which also includes the site of the rūnaka’s native fish protection project.
The name long-jaw is a clue as to how to recognise it – it has a long protruding lower jaw. It is a slender, elongated, small fish that is usually creamish-grey with bold greenish-grey blotches and spots on back and sides. Galaxiids are a group of Southern Hemisphere fish that don’t have scales and, a dorsal fin located very close to the tail.
Five species of galaxias are migratory and the rest have diversified to live their lives in freshwater. The upland long-jaw likes the cooler waters of mountain spring streams, many above the post-glacial lakes.
Upland long-jaw galaxias eat invertebrates and mostly feed at night. They like good shade along the river bank. Not only do introduced trout compete with native fish for habitat and food, they also feed on the native galaxias. The cool springs in the Fork Stream valley system provide the conditions in which they are able to thrive.
Photos : Wikimedia Commons credit Simon Howard and Simon Elkington
