Nevis galaxias (Galaxias 'nevis') are found in tannin-stained waterways solely above the gorge on the lower Nevis River where it joins the Kawarau River. This area was made famous from the ‘kings gate’ in the Lord of the Rings trilogy.
Features of Nevis galaxias include:
- bronze to grey-brown in colour and covered in darker brown splotches
and silver speckling
- long, streamlined bodies with large fins, which help them climb
- typically grow up to 100 mm in length but can get to 170 mm
- feed on small stream invertebrates such as mayflies and stoneflies
- spawn in spring (October to November) laying small 3 mm eggs in vegetation on stream banks during flood flows.
This taxa is currently indeterminate and has not been formally described to date. Work is currently being undertaken to look into formal description.
Over the last decade we have lost 25% of known galaxiid populations. This can be directly linked to the spread of sports fish (trout and brook char), which eat galaxiids; and changes in land use such as stock access to streams, reduction of native vegetation, land development and forest harvesting.
These land use changes impact on the streams in which galaxiids live, increasing sedimentation, changing natural flows through water abstraction, and reducing the amount of habitat available for spawning.
This map shows the known locations of Nevis galaxias, as at 2013.
Schoolhouse Creek in Nevis Valley: Nevis galaxias habitat
Source: New Zealand freshwater fish database