[6] The ship's owner, John Sen Inches Thomson, wrote a book on his sea travels, including his time on the island.

[8] On the recommendation of Fysh, the Tasmanian Legislative Council passed a motion on 24 July 1890 requesting the "necessary steps be taken" for Macquarie Island to be transferred to New Zealand.

[15] On 20 April 1891, regulations issued by the Tasmanian Commissioner of Fisheries for the protection of seals on Macquarie Island came into effect.

[16] Between 1902 and 1920, the Tasmanian Government leased the island to Joseph Hatch (1837–1928) for his oil industry based on harvesting penguins.

[18][21] On 23 December 2004, an earthquake measuring 8.1 on the moment magnitude scale rocked the island but caused no significant damage.

[2] The island consists of plateaus at north and south ends, each of 150–200 m (490–660 ft) elevation, joined by a low, narrow isthmus.

The Bishop and Clerk Islets mark the southernmost point of Australia (excluding the Australian Antarctic Territory).

It is part of the Macquarie Ridge, a 1,600 kilometres (990 mi) long fault zone in the oceanic crust, running southwestwards from New Zealand along the plate boundary.

However, in earlier geologic time the two plates had been moving apart, allowing lava from the earth's mantle to rise to the seafloor, forming basalt.

The island is an example of an ophiolite - a section of Earth's oceanic crust and the underlying upper mantle that has been uplifted and exposed.

[26]The unique exposures include excellent examples of pillow basalts without any hint of continental crust contamination and other extrusive rocks.

Macquarie Island's climate is moderated by the sea, and all months have an average temperature above freezing; although snow is common between June and October, and may even occur in summer.

This is a considerably lower figure than at Heard Island due to its longitude, which receives 96.8 snowy days at only 53 degrees south.

The island has been identified by BirdLife International as an Important Bird Area because it supports about 3.5 million breeding seabirds of 13 species.

[38] In December 1997, Macquarie Island was listed as UNESCO World Heritage Site, including the reserve and the surrounding waters out to 12 nautical miles.

[43] Rats and mice feeding on young chicks, and rabbits nibbling on the grass layer, has led to soil erosion and cliff collapses, destroying seabird nests.

In September 2006 a large landslip at Lusitania Bay, on the eastern side of the island, partially destroyed an important penguin breeding colony.

Tasmania Parks and Wildlife Service attributed the landslip to a combination of heavy spring rains and severe erosion caused by rabbits.

[44] Research by Australian Antarctic Division scientists, published in the 13 January 2009 issue of the British Ecological Society's Journal of Applied Ecology, suggested that the success of the feral cat eradication program has allowed the rabbit population to increase, damaging the Macquarie Island ecosystem by altering significant areas of island vegetation.

[45] However, in a comment published in the same journal other scientists argued that a number of factors (primarily a reduction in the use of the Myxoma virus) were almost certainly involved and the absence of cats may have been relatively minor among them.

On 4 June 2007, a media release by Malcolm Turnbull, Federal Minister for Australia's Environment and Water Resources Board, announced that the Australian and Tasmanian Governments had reached an agreement to jointly fund the eradication of rodent pests, including rabbits, to protect Macquarie Island's World Heritage values.

[51] The baiting was expected to inadvertently affect kelp gulls, but greater-than-expected bird deaths caused the program to be suspended.

[53] In April 2012 the hunting teams reported the extermination of 13 rabbits that had survived the 2011 baiting; the last five were found in November 2011, including a lactating doe and four kittens.

[58] However, ongoing monitoring, along with measures such as the use of biosecurity dogs to check cargo with the island as its destination are necessary, as there are new threats such as climate change and avian influenza.

[59] Despite being declared pest-free, Macquarie Island is still inhabited by several invasive bird species, such as the domestic mallard and European starling.

The self-introduction of domestic mallards from New Zealand has become a threat to the Pacific black duck population on Macquarie Island through introgressive hybridisation.

[63] However, shortly afterwards, the Australian government responded to widespread backlash by announcing funding to upgrade ageing infrastructure and continue existing operations.

[63] In 2018, the Australian Antarctic Division published a map showing the island's buildings with confirmed or suspected asbestos contamination, which included at least half the structures there.

[64] In April 2024, Permanent Daylight-Saving Time on Macquarie Island was abolished by the Huon Valley Council and was changed to Summer DST.

[66] In part to carry out this mission, as of 2023, the Navy's Armidale-class boats are in the process of being replaced by larger Arafura-class offshore patrol vessels.