Codfish island or Whenua Hou is a small island (14 km²) located to the east of Stewart Island in southern New Zealand. It is a predator-free bird sanctuary and the focus of kakapo recovery efforts. The majority of the breeding population of critically endangered kakapo are currently located on this island. The island is also home to southern short-tailed bats, kaka, fernbirds, red- and yellow-crowned parakeets, and a recently introduced population of yellowheads (mohua). Yellow-eyed and Fiordland crested penguins breed along the coastline

The island is inhabited by Department of Conservation field workers along with public volunteers. The sole hut is located at Sealer's Bay with access by light aircraft or helicopter. The island is closed to visitors with unauthorised landing prohibited.