The island is one of many geographic features in New Zealand to have a
dual place name, consisting of the English and
Māori names separated by a slash. The English name "Codfish Island" refers to the endemic
blue cod. The island was named Pegasus Island in 1808 by whaler
Eber Bunker after sealers had landed there and began European habitation. By 1824 it was known as both Codfish Island and Whenua Hou. In about 1815 a mixed-race settlement of sealers and Māori women was established there. This encouraged sealers, such as
Thomas Chaseland to move to Whenua Hou, alleviating the issues which their presence had caused on nearby Stewart Island and making Whenua Hou one of the first permanent mixed Māori and European settlements in the region. The
Department of Conservation sought to create a plan to conserve the island's cultural and historic sites. In 2007 an investigation into the history and archaeology of the island was undertaken by Angela Middleton, Ian Smith and
Atholl Anderson. Field investigations were carried out over two weeks and included a survey of possible sites of human activity as well as detailed investigations and excavation in Sealers Bay, the only site of human occupation. The first was from the 13th–15th century, indicating settlement during the Māori occupation of New Zealand, and the second was historic 19th century occupation from about 1800 to 1830. == Wildlife ==