The Cardrona River is in Otago in the South Island of New Zealand. It is one of the first tributaries of the Clutha River, which it meets only 5 kilometres from the latter's origin at the outflow of Lake W?naka. The Cardrona and it tributaries provide important spawning areas for the upper Clutha. Juvenile trout will stay in the tributaries for as long as possible and then be pushed downstream by floods. Most adult trout leave the Cardrona by the end of November/early December [Fishing Regulations](https://fishandgame.org.nz/assets/Uploads/FG-Fishing-Regs-SI-20-21-.pdf)