A 21-mile-long island in the southwest corner of the Pacific Ocean, lying halfway between Australia and Antarctica, Macquarie is the only landmass in the world where rocks from the Earth’s mantle are exposed above sea level. This exposed portion of mantle is known as the Macquarie Ridge, which is part of the Macquarie Fault, the tectonic boundary between the Indo-Australian Plate and the Pacific Plate.
In December 2004, an 8.1 earthquake – one of the largest quakes ever recorded -- rocked the island along this fault, causing little damage to this tough little plot of land. No woodland plants or trees grow here, but the island is covered with grasses, herbs and wetlands.
Home to seasonal migrations of penguins and seals, the harsh weather conditions on Macquarie have kept it largely safe from human habitation. Discovered and claimed for Britain in 1810, then annexed to Australia’s New South Wales, the island was used as a occasional base of operations and weather station (and only briefly at any one visit) by an Australian team of Antarctic explorers from 1911 to 1914. Closed in 1915, the station’s buildings remain here, abandoned and intact.
Since 1933, Macquarie has been considered a Tasmanian wildlife sanctuary due to its rotating population of approximately 3.5 million seabirds, spread across 13 different species. In 1972, when it became clear that feral cats, rats and rabbits (all brought by explorers’ ships) were causing harm to these seabird populations and their breeding grounds, the island was officially named a Tasmanian State Reserve. In 2000, the last of these cats was culled, and by 2012, the rabbits and rats had been eradicated, as well.