South Island takahe do not have any native predators. Populations have declined as a result of anthropogenic changes such as habitat destruction and modification, hunting, and the introduction of mammalian predators and competitors, including dogs, red deer, and stoats.
- Baber, M., J. Craig. 2003. Home land range and carrying capacity of the South Island takahe (Porphyrio hochstetteri) on Tiritiri Matagni Island. Notornis, 50: 67-74. Accessed April 10, 2008 at www.google.com/scholar.
- Jamieson, I., C. Ryan. 2000. Increased egg infertility associated with translocating inbred takahe (Porphyrio hochstetteri) to island refuges in New Zealand. Biological Consevation, 94: 107-114. Accessed April 02, 2008 at www.google.com/scholar.