In 1803, French explorer Louis de Freycinet, captain of the Casuarina, named the island Île Pelée (Bald Island). It was also known as Île Lévilian and later Île Berthelot. In 1827, James Stirling changed its name to Pulo Carnac Island in honour of John Rivett Carnac, Second Lieutenant on his ship HMS Success. "Pulo" is Malay for "Island"; it is not known why Stirling included the term, and it was soon dropped. In the early days of the Swan River Colony the island was used as a penal settlement for Indigenous Australians.
The island is home to Australian sea lions, bottlenose dolphins and a large range of marine bird life. It is particularly noted for the abundance of snakes, particularly tiger snakes, which live there. For this reason, very few people venture there. There is no permanent fresh water, providing a challenge for the animals that live there. The origins of the tiger snake colony has attracted significant debate and research into how that species has adapted to a harsh island habitat.
- Carnac Island Nature Reserve : management plan [Perth, W.A.] : The Commission, 2003. Management plan (Western Australia. Dept. of Conservation and Land Management) ; no. 47