Michaelmas Island is an island

Island

An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or lake may be called an eyot , or holm...

 located in King George Sound

King George Sound

King George Sound is the name of a sound on the south coast of Western Australia. Located at , it is the site of the city of Albany.The sound covers an area of and varies in depth from to ....

 near Albany, Western Australia

Albany, Western Australia

Albany is a port city in the Great Southern region of Western Australia, some 418 km SE of Perth, the state capital. As of 2009, Albany's population was estimated at 33,600, making it the 6th-largest city in the state....

.
The island is a nature reserve

Nature reserve

A nature reserve is a protected area of importance for wildlife, flora, fauna or features of geological or other special interest, which is reserved and managed for conservation and to provide special opportunities for study or research...

 (declared in 1983) and managed by the Department of Environment and Conservation; its reserve number is 30049. The island is also registered as a national estate. The island is 91.9 hectares (227 acre) in area.
Michaelmas Island has steep rocky shores with submerged reefs all along its northern southern and eastern sides in depths up to 30 metres (98.4 ft) with large granite

Granite

Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

 boulders. The faces are covered in a diverse range in coral

Coral

Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...

s and sponges and home to a wide variety of marine life. A whale chaser “Cheynes III” that was scuttled in 1982 is located off the western side of the island and is regarded highly as a diving site.

Michaelmas Island is an important habitat

Habitat

* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...

 for both resident and migratory

Bird migration

Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...

 birds. The habitat of these species is threatened by weed invasion such as Taylorina

Psoralea pinnata

Psoralea pinnata is an erect evergreen shrub or small tree that grows to a height of to tall.- Description :This plant has fine deep green linear leaves that are deeply divided with a length of about...

 and feral

Feral

A feral organism is one that has changed from being domesticated to being wild or untamed. In the case of plants it is a movement from cultivated to uncultivated or controlled to volunteer. The introduction of feral animals or plants to their non-native regions, like any introduced species, may...

 animals such as rats.

George Vancouver

George Vancouver

Captain George Vancouver RN was an English officer of the British Royal Navy, best known for his 1791-95 expedition, which explored and charted North America's northwestern Pacific Coast regions, including the coasts of contemporary Alaska, British Columbia, Washington and Oregon...

 named many of the landforms around Albany when he entered King George Sound in 1791 including Michaelmas Island (discovered on Michaelmas Day), King George Sound

King George Sound

King George Sound is the name of a sound on the south coast of Western Australia. Located at , it is the site of the city of Albany.The sound covers an area of and varies in depth from to ....

, Breaksea Island, Oyster Harbour and Point Possession. Vancouver described the island as being covered in rich grasses and other vegetables. Before leaving he planted some vine cuttings, some water cresses, and sowed various seeds.
Matthew Flinders

Matthew Flinders

Captain Matthew Flinders RN was one of the most successful navigators and cartographers of his age. In a career that spanned just over twenty years, he sailed with Captain William Bligh, circumnavigated Australia and encouraged the use of that name for the continent, which had previously been...

landed on the island in 1801 and reported the island to be covered in wiry grasses and stunted shrubs, also it was covered it rat holes.