Carnac Island

Carnac Island is a small nature reserve lying offshore from Fremantle, between the mainland and Garden Island. Known to the Whadjuk Noongar people as Ngooloormayup, the island has a long human history as well as considerable importance for wildlife. It was named Carnac Island by James Stirling in honour of naval officer John Rivett Carnac. During the early years of the Swan River Colony it was briefly used to hold Aboriginal prisoners, and later had associations with whaling, quarantine and defence. Today it is managed primarily for conservation.

The island is particularly well known for its wildlife. Australian sea lions regularly haul out along its beaches, while the island and surrounding waters support seabirds, king skinks and a remarkably dense population of tiger snakes. Nesting birds include species such as fairy terns, wedge-tailed shearwaters and pied cormorants.

Perhaps Carnac Island's most famous residents are its tiger snakes. Exactly how the snakes first reached the island has long been debated, but one extraordinary local story dates from the late 1920s. Snake showman Richard "Rocky" Vane reportedly kept a large collection of tiger snakes as part of his performances. After his wife died following a snake bite and authorities shut down his show, Vane was allegedly ordered to dispose of his snakes. According to an account later given by a man who said he accompanied him, Vane took a boat to Carnac Island and released somewhere around 70 to 100 tiger snakes there.

For many years the story was treated largely as local legend, with other theories suggesting that tiger snakes had been isolated on the island by rising sea levels thousands of years ago or had reached it naturally by swimming. More recent historical research, however, has lent substantial support to the idea that snakes were deliberately released on Carnac during the early twentieth century, although the precise history of the population remains an interesting subject of research.

Carnac's snakes have another unusual characteristic: many have damaged or missing eyes, and some are completely blind. This isn't an inherited feature unique to the island. Tiger snakes raid seabird colonies for chicks, and adult silver gulls vigorously defend their nests by pecking at the snakes, sometimes destroying one or both eyes. Remarkably, completely blind snakes have been found surviving for years, remaining healthy and even reproducing. They can continue hunting prey such as young seabirds despite losing their sight.

For visiting sailors, Carnac Island is an attractive day destination, particularly for its sheltered eastern side, clear water, snorkelling and wildlife viewing. However, it is a protected nature reserve and access to the island is prohibited. Sea lions should also be given plenty of space.

• Large sandy areas on eastern side.
• Smaller deep anchorage on western side