The Great Oʻahu crake or Great Oʻahu rail (Porzana ralphorum) is an extinct bird species endemic to the island of Oʻahu in Hawaiʻi. It was one of two flightless rails that had survived on the island until the arrival of people in 200 C.E. The cause of extinction is not very well known, but we can speculate that it was hunted for meat, and that its bones and feathers were used for decoration. It may have also have been attacked by the Polynesian rats that were introduced by early settlers.