Hen Island is a long, narrow, 7.6 hectare

Hectare

The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2...

 island in south-eastern Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

. It is part of the Maatsuyker Island Group

Maatsuyker Islands

The Maatsuyker Islands Group is a group of islands and rocks located 5.5 kilometres off the south coast of Tasmania. Maatsuyker Island is the southernmost island of the group and of the Australian continental shelf. There are exposed rocks further south of Maatsuyker but they do not meet the...

, lying close to the southern end of the south-western coast of Tasmania

Tasmania

Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...

. Its highest point is 75 m Above Sea Level

Above mean sea level

The term above mean sea level refers to the elevation or altitude of any object, relative to the average sea level datum. AMSL is used extensively in radio by engineers to determine the coverage area a station will be able to reach...

. It is part of the Southwest National Park

Southwest National Park

The Southwest National Park is a national park located in the south-west of Tasmania, Australia. The park is Tasmania's largest and forms part of the Tasmanian Wilderness World Heritage Area....

, and thus within the Tasmanian Wilderness

Tasmanian Wilderness

The Tasmanian Wilderness is a term that is used for a range of areas in Tasmania, Australia.The World Heritage Areas in South West, Western and Central are the most well known. However, there are also other areas in Tasmania that have the elements of being known as wilderness areas, the Tarkine...

 World Heritage Site

World Heritage Site

A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...

. The island is part of the Maatsuyker Island Group Important Bird Area

Important Bird Area

An Important Bird Area is an area recognized as being globally important habitat for the conservation of bird populations. Currently there are about 10,000 IBAs worldwide. The program was developed and sites are identified by BirdLife International...

, identified as such by BirdLife International

BirdLife International

BirdLife International is a global Partnership of conservation organisations that strives to conserve birds, their habitats and global biodiversity, working with people towards sustainability in the use of natural resources...

 because of its importance as a breeding site for seabirds.

Fauna

Recorded breeding seabird

Seabird

Seabirds are birds that have adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations...

 and wader

Wader

Waders, called shorebirds in North America , are members of the order Charadriiformes, excluding the more marine web-footed seabird groups. The latter are the skuas , gulls , terns , skimmers , and auks...

 species are the Little Penguin

Little Penguin

The Little Penguin is the smallest species of penguin. The penguin, which usually grows to an average of in height and in length , is found on the coastlines of southern Australia and New Zealand, with possible records from Chile.Apart from Little Penguins, they have several common names...

 (90 pairs), Short-tailed Shearwater

Short-tailed Shearwater

The Short-tailed Shearwater or Slender-billed Shearwater , also called Yolla or Moonbird, and commonly known as the muttonbird in Australia, is the most abundant seabird species in Australian waters, and is one of the few Australian native birds in which the chicks are commercially harvested...

 12,000 pairs), Fairy Prion

Fairy Prion

The Fairy Prion is a small seabird with the standard prion plumage of black upperparts and white underneath with an "M" wing marking.-Taxonomy:...

 (27,000 pairs), Pacific Gull

Pacific Gull

The Pacific Gull is a very large gull, native to the coasts of Australia. It is moderately common between Carnarvon in the west, and Sydney in the east, although it has become scarce in some parts of the south-east, as a result of competition from the Kelp Gull, which has "self-introduced" since...

 and Sooty Oystercatcher

Sooty Oystercatcher

The Sooty Oystercatcher, Haematopus fuliginosus, is a species of oystercatcher. It is a wading bird native to Australia and commonly found on its coastline. It prefers rocky coastlines, but will occasionally live in estuaries....

. The Metallic Skink

Metallic Skink

The Metallic Cool-skink or Metallic Skink is a species of skink in the Scincidae family. It is endemic to Australia, found in southern Victoria, as well as in Tasmania where it is the most widespread and common lizard, occurring on many offshore islands in Bass Strait as well as the mainland. It...

is present.