The Territory of Heard Island and McDonald Islands
(HIMI
) is an Australian
external territory
A dependent territory, dependent area, or dependency (sometimes referred as an external territory) is a territory that does not possess full political independence or sovereignty as a sovereign state, yet remains politically outside the controlli ...
comprising a
volcanic group
A volcanic group is a stratigraphic group consisting of volcanic strata. They can be in the form of volcanic fields, volcanic complexes and cone
A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequ ...
of mostly barren
Antarctic
The Antarctic ( or , American English also or ; commonly ) is a polar region around Earth's South Pole, opposite the Arctic region around the North Pole. The Antarctic comprises the continent of Antarctica, the Kerguelen Plateau and other ...
islands, about two-thirds of the way from
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...
to
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...
. The group's overall size is in area and it has of coastline. Discovered in the mid-19th century, the islands lie on the
Kerguelen Plateau
The Kerguelen Plateau (, ), also known as the Kerguelen–Heard Plateau, is an oceanic plateau and a large igneous province (LIP) located on the Antarctic Plate, in the southern Indian Ocean. It is about to the southwest of Australia and is ...
in the
Indian Ocean
The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by th ...
and have been an Australian territory since 1947. They contain Australia's only two active
volcano
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
On Earth, volcanoes are most often found where tectonic plates are ...
es. The summit of one,
Mawson Peak
Mawson Peak is an active volcanic summit of the Big Ben massif on Heard Island, an external Australian territory in the Indian Ocean.
With an elevation of , it is the third highest peak in any state or territory of Australia, higher than th ...
, is higher than any mountain in all other Australian states or territories, except
Dome Argus
Dome A or Dome Argus is the loftiest ice dome on the Antarctic Plateau, located inland. It is thought to be the coldest naturally occurring place on Earth, with temperatures believed to reach . It is the highest ice feature in Antarctica, consis ...
,
Mount McClintock
Mount McClintock is the highest mountain () in the Britannia Range in Antarctica, surmounting the south end of Forbes Ridge, east of Mount Olympus. It was discovered by the ''Discovery'' expedition (1901–04) and named for Admiral Sir Leopold ...
and
Mount Menzies Mount Menzies is the culminating peak (3,355 m; 11,007 ft) on the large massif between Mount Mather and Mount Bayliss, standing on the south side of Fisher Glacier, Antarctica. It was sighted by Flying Officer J. Seaton from an ANARE Beav ...
in the
Australian Antarctic Territory
The Australian Antarctic Territory (AAT) is a part of East Antarctica claimed by Australia as an external territory. It is administered by the Australian Antarctic Division, an agency of the federal Department of Climate Change, Energy, the Env ...
.
The islands are among the
most remote places on Earth: They are located about southwest of
Perth
Perth is the capital and largest city of the Australian state of Western Australia. It is the fourth most populous city in Australia and Oceania, with a population of 2.1 million (80% of the state) living in Greater Perth in 2020. Perth is ...
,
southwest of
Cape Leeuwin
Cape Leeuwin is the most south-westerly (but not most southerly) mainland point of the Australian continent, in the state of Western Australia.
Description
A few small islands and rocks, the St Alouarn Islands, extend further in Flinders Ba ...
, Australia, southeast of
South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...
, southeast of
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...
, north of Antarctica, and southeast of the
Kerguelen Islands
The Kerguelen Islands ( or ; in French commonly ' but officially ', ), also known as the Desolation Islands (' in French), are a group of islands in the sub-Antarctic constituting one of the two exposed parts of the Kerguelen Plateau, a large ...
(part of
French Southern and Antarctic Lands
The French Southern and Antarctic Lands (french: Terres australes et antarctiques françaises, TAAF) is an Overseas Territory (french: Territoire d'outre-mer or ) of France. It consists of:
# Adélie Land (), the French claim on the continent ...
).
The islands are uninhabited, and can only be reached by sea, which from Australia would take two weeks.
History
![FMIB 46007 Antarctic Sea-Elephant Fishery](https://upload.wikimedia.org/wikipedia/commons/2/20/FMIB_46007_Antarctic_Sea-Elephant_Fishery.jpeg)
Neither island cluster had recorded visitors until the mid-1850s.
An American sailor, John Heard, on the ship ''Oriental'', sighted Heard Island on 25 November 1853, en route from
Boston
Boston (), officially the City of Boston, is the state capital and most populous city of the Commonwealth of Massachusetts, as well as the cultural and financial center of the New England region of the United States. It is the 24th- mo ...
to Melbourne. He reported the discovery one month later and had the island named after him. William McDonald aboard the ''Samarang''
discovered the nearby McDonald Islands six weeks later, on 4 January 1854.
No landing took place on the islands until March 1855, when sealers from the ''Corinthian'', led by
Erasmus Darwin Rogers
Desiderius Erasmus Roterodamus (; ; English: Erasmus of Rotterdam or Erasmus;''Erasmus'' was his baptismal name, given after St. Erasmus of Formiae. ''Desiderius'' was an adopted additional name, which he used from 1496. The ''Roterodamus'' wa ...
, went ashore at a place called Oil Barrel Point. From 1855 to 1882 a number of American sealers spent a year or more on the island, living in appalling conditions in dark smelly huts, also at Oil Barrel Point. At its peak the community consisted of 200 people. By 1880, sealers had wiped out most of the seal population and then left the island. In all, the islands furnished more than 100,000 barrels of
elephant seal
Elephant seals are very large, oceangoing earless seals in the genus ''Mirounga''. Both species, the northern elephant seal (''M. angustirostris'') and the southern elephant seal (''M. leonina''), were hunted to the brink of extinction for oil ...
oil during this period.
A number of wrecks have occurred in the vicinity of the islands. There is also a discarded building left from John Heard's sealing station that is situated near Atlas Cove.
The islands were formally claimed by the United Kingdom in 1910 and transferred to Australia on 26 December 1947. The receipt was confirmed in letters exchanged on 19 December 1950.
The archipelago became a
World Heritage Site
A World Heritage Site is a landmark or area with legal protection by an international convention administered by the United Nations Educational, Scientific and Cultural Organization (UNESCO). World Heritage Sites are designated by UNESCO for h ...
in 1997.
The first recorded landing on McDonald Island was made by Australian scientists Grahame Budd and Hugh Thelander on 12 February 1971, using a helicopter.
There were at least five private expeditions to Heard Island between 1965 and 2000. Several
amateur radio
Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communic ...
operators have visited Heard, often associated with scientific expeditions. The first activity there was in 1947 by Alan Campbell-Drury. Two amateur radio
DXpedition
A DX-pedition is an expedition to what is considered an exotic place by amateur radio operators and DX listeners, typically because of its remoteness, access restrictions, or simply because there are very few radio amateurs active from that pl ...
s to the island took place in 1983 using the callsigns VK0HI (the ''Anaconda'' expedition)
and VK0JS and VK0NL (the ''Cheynes II'' expedition), with a further operation in January 1997 (VK0IR). The DXpedition in March 2016 (VK0EK) was organised by Cordell Expeditions, and made over 75,000 radio contacts.
Mawson Peak, atop Big Ben, was first climbed on 25 January 1965 by five members of the Southern Indian Ocean Expedition to Heard Island (sometimes referred to as the ''Patanela'' expedition). The second ascent was made by five members of the Heard Island Expedition 1983 (sometimes referred to as the ''Anaconda'' expedition).
A helicopter landing was made at the summit by an ANARE team on 21 December 1986. An Australian Army team was successful in making the third ascent in 2000.
In 1991, the islands were the location for the
Heard Island feasibility test
Heard may refer to:
*Hearing (sense)
*Heard (surname)
*The Heard, an American 1960s garage rock band
*Heard Island and McDonald Islands, an Australian external territory
*Heard County, Georgia, U.S.
See also
*Herd
*Hird
The hird (also named "H ...
, an experiment in very long-distance transmission of low frequency sound through the ocean. The US Navy vessels and were used to transmit signals which could be detected as far away as both ocean coasts of the US and Canada.
Geography
Heard Island, by far the largest of the group, is a mountainous island covered by 41 glaciers (the island is 80% covered with ice) and dominated by the Big Ben
Big Ben is the nickname for the Great Bell of the Great Clock of Westminster, at the north end of the Palace of Westminster in London, England, and the name is frequently extended to refer also to the clock and the clock tower. The officia ...
massif
In geology, a massif ( or ) is a section of a planet's crust that is demarcated by faults or flexures. In the movement of the crust, a massif tends to retain its internal structure while being displaced as a whole. The term also refers to a ...
. It has a maximum elevation of at Mawson Peak
Mawson Peak is an active volcanic summit of the Big Ben massif on Heard Island, an external Australian territory in the Indian Ocean.
With an elevation of , it is the third highest peak in any state or territory of Australia, higher than th ...
, the historically active volcanic summit of Big Ben. A July 2000 satellite image from the University of Hawaii
A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United States, th ...
's Institute of Geophysics and Planetology (HIGP) Thermal Alert Team showed an active and 50- to 90-metre-wide (164–295 ft) lava flow trending south-west from the summit of Big Ben.
The much smaller and rocky McDonald Islands
The McDonald Islands () are an uninhabited archipelago in the southern Indian Ocean in the vicinity of Heard Island (). Together with Heard Island, they make up the Australian external Territory of Heard Island and McDonald Islands. The McDonal ...
are located to the west of Heard Island. They consist of McDonald Island ( high), Flat Island ( high) and Meyer Rock
Meyer Rock () is a pinnacle rock northwest of McDonald Island in the McDonald Islands. This feature was charted as "Meyers Rock" on an 1874 chart by the British Challenger expedition
The ''Challenger'' expedition of 1872–1876 was a scienti ...
( high). They total approximately in area, where McDonald Island is . There is a small group of islets and rocks about north of Heard Island, consisting of Shag Islet, Sail Rock, Morgan Island and Black Rock. They total about in area.
Mawson Peak and McDonald Island are the only two active volcanoes in Australian territory. Mawson Peak is also one of the highest Australian mountains (higher than Mount Kosciuszko
Mount Kosciuszko ( ; Ngarigo: , ), previously spelled Mount Kosciusko, is mainland Australia's tallest mountain, at 2,228 metres (7,310 ft) above sea level. It is located on the Main Range of the Snowy Mountains in Kosciuszko National ...
); surpassed only by Mount McClintock
Mount McClintock is the highest mountain () in the Britannia Range in Antarctica, surmounting the south end of Forbes Ridge, east of Mount Olympus. It was discovered by the ''Discovery'' expedition (1901–04) and named for Admiral Sir Leopold ...
range in the Antarctic territory. Mawson Peak has erupted several times in the last decade; the most recent eruption was filmed on 2 February 2016. The volcano on McDonald Island, after being dormant for 75,000 years, became active in 1992 and has erupted several times since, the most recent in 2005.
Heard Island and the McDonald Islands have no ports or harbours; ships must anchor offshore. The coastline is , and a territorial sea and exclusive fishing zone are claimed.
Wetlands
Heard Island has a number of small wetland sites scattered around its coastal perimeter, including areas of wetland vegetation, lagoons or lagoon complexes, rocky shores and sandy shores, including the Elephant Spit
Elephant Spit is a 9 km long sand spit at the eastern end of subantarctic Heard Island, in the Australian territory of Heard Island and McDonald Islands, lying in the Southern Ocean on the Kerguelen Plateau about 450 km south-east of t ...
. Many of these wetland areas are separated by active glaciers. There are also several short glacier-fed streams and glacial pools. Some wetland areas have been recorded on McDonald Island but, due to substantial volcanic activity since the last landing was made in 1980, their present extent is unknown.
The HIMI wetland is listed on the Directory of Important Wetlands in Australia A Directory of Important Wetlands in Australia (DIWA) is a list of wetlands of national importance to Australia published by the governmental agency Environment Australia. Intended to augment the list of wetlands of international importance under t ...
and, in a recent analysis of Commonwealth-managed wetlands, was ranked highest for nomination under the Convention on Wetlands of International Importance Especially as Waterfowl Habitat (Ramsar Convention) as an internationally important wetland.
Six wetland types have been identified from HIMI covering approximately 1860 ha: coastal 'pool complex' (237 ha); inland 'pool complex' (105 ha); vegetated seeps mostly on recent glaciated areas (18 ha); glacial lagoons (1103 ha); non-glacial lagoons (97ha); Elephant Spit (300 ha) plus some coastal areas. On Heard Island, the majority of these types suites are found below 150 m asl. The wetland vegetation occurs in the 'wet mixed herbfield' and 'coastal biotic vegetation' communities described above.
The wetlands provide important breeding and feeding habitat for a number of Antarctic and subantarctic wetland animals. These include the southern elephant seal
The southern elephant seal (''Mirounga leonina'') is one of two species of elephant seals. It is the largest member of the clade Pinnipedia and the order Carnivora, as well as the largest extant marine mammal that is not a cetacean. It gets it ...
and macaroni
Macaroni (, Italian: maccheroni) is dry pasta shaped like narrow tubes.Oxford DictionaryMacaroni/ref> Made with durum wheat, macaroni is commonly cut in short lengths; curved macaroni may be referred to as elbow macaroni. Some home machines ...
, gentoo, king
King is the title given to a male monarch in a variety of contexts. The female equivalent is queen, which title is also given to the consort of a king.
*In the context of prehistory, antiquity and contemporary indigenous peoples, the tit ...
and eastern rockhopper penguins, considered to be wetland species under the Ramsar Convention. Non-wetland vegetated parts of the islands also support penguin and other seabird colonies.
Climate
The islands have an Antarctic climate, tempered by their maritime setting. The weather is marked by low seasonal and daily temperature ranges, persistent and generally low cloud cover, frequent precipitation and strong winds. Snowfall occurs throughout the year. Monthly average temperatures at Atlas Cove (at the northwestern end of Heard Island) range from , with an average daily range of in summer and in winter. The winds are predominantly westerly and persistently strong. At Atlas Cove, monthly average wind speeds range between around . Gusts in excess of have been recorded. Annual precipitation at sea level on Heard Island is on the order of ; rain or snow falls on about 3 out of 4 days.
Meteorological records at Heard Island are incomplete.
Wildlife
Flora
Constraints
The islands are part of the Southern Indian Ocean Islands tundra
The Southern Indian Ocean Islands tundra is a tundra ecoregion that includes several subantarctic islands in the southern Indian Ocean.
Location and description
The ecoregion stretches from Prince Edward Islands in the west, past the Crozet ...
ecoregion
An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of l ...
that includes several subantarctic
The sub-Antarctic zone is a region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46° and 60° south of the Equator. The subantarctic region includes many islands ...
islands. In this cold climate plant life is mainly limited to grasses, lichens, and moss
Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...
es. Low plant diversity reflects the islands' isolation, small size, severe climate, the short, cool growing season and, for Heard Island, substantial permanent ice cover. The main environmental determinants of vegetation on subantarctic islands are wind exposure, water availability, parent soil composition, salt spray exposure, nutrient availability, disturbance by trampling (from seabirds and seals) and, possibly, altitude. At Heard Island, exposure to salt spray and the presence of breeding and moulting seabirds and seals are particularly strong influences on vegetation composition and structure in coastal areas.
History
Evidence from microfossil records indicates that ferns and woody plants were present on Heard Island during the Tertiary
Tertiary ( ) is a widely used but obsolete term for the geologic period from 66 million to 2.6 million years ago.
The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start ...
(a period with a cool and moist climate). Neither group of plants is present today, although potential Tertiary survivors include the vascular plant ''Pringlea antiscorbutica
''Pringlea antiscorbutica'', commonly known as Kerguelen cabbage, is a flowering plant and the sole member of the monotypic genus ''Pringlea'' in the family Brassicaceae. Its common name comes from the archipelago of its discovery, the Kerguelen ...
'' and six moss species. Volcanic activity has altered the distribution and abundance of the vegetation. The vascular flora covers a range of environments and, although only six species are currently widespread, glacial retreat and the consequent connection of previously separate ice-free areas is providing opportunities for further distribution of vegetation into adjacent areas.
Flowering plants and ferns
Low-growing herbaceous
Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials.
Definitions of "herb" and "herbaceous"
The fourth edition of t ...
flowering plants and bryophyte
The Bryophyta s.l. are a proposed taxonomic division containing three groups of non-vascular land plants (embryophytes): the liverworts, hornworts and mosses. Bryophyta s.s. consists of the mosses only. They are characteristically limited in ...
s are the major vegetation components. The vascular flora comprises the smallest number of species of any major subantarctic island group, reflecting its isolation, small ice-free area and severe climate. Twelve vascular species are known from Heard Island, of which five have also been recorded on McDonald Island. None of the vascular species are endemic, although ''Pringlea antiscorbutica
''Pringlea antiscorbutica'', commonly known as Kerguelen cabbage, is a flowering plant and the sole member of the monotypic genus ''Pringlea'' in the family Brassicaceae. Its common name comes from the archipelago of its discovery, the Kerguelen ...
'', '' Colobanthus kerguelensis'', and '' Poa kerguelensis'' occur only on subantarctic islands in the southern Indian Ocean.
The plants are typically subantarctic, but with a higher abundance of the cushion-forming ''Azorella selago
''Azorella selago'' is a species of cushion plant native to the sub-Antarctic islands of the Southern Ocean, including the Crozet Islands, the Possession Islands, the Heard Island and McDonald Islands, the Kerguelen Islands, and the Prince Edward ...
'' than other subantarctic islands. Heard Island is the largest subantarctic island with no confirmed human-introduced plants. Areas available for plant colonisation on Heard Island are generally the result of retreating glaciers or new ice-free land created by lava flows. Today, substantial vegetation covers over 20 km2 of Heard Island, and is best developed on coastal areas at elevations below 250 m.
Mosses and liverworts
Bryophyte
The Bryophyta s.l. are a proposed taxonomic division containing three groups of non-vascular land plants (embryophytes): the liverworts, hornworts and mosses. Bryophyta s.s. consists of the mosses only. They are characteristically limited in ...
s (mosses and liverworts) contribute substantially to the overall biodiversity of Heard Island, with 43 mosses and 19 liverworts being recorded, often occupying habitats unsuitable for vascular plants, such as cliff faces. Bryophytes are present in most of the major vegetation communities including several soil and moss-inhabiting species. A 1980 survey of McDonald Island found lower diversity than that on Heard Island; four mosses and a number of algal species are recorded from there.
Algae
At least 100 species of terrestrial algae are known from Heard Island, commonly in permanently moist and ephemeral habitats. Forests of the giant Antarctic kelp ''Durvillaea antarctica
''Durvillaea antarctica'', also known as ' and ', is a large, robust species of southern bull kelp found on the coasts of Chile, southern New Zealand, and Macquarie Island.Smith, J.M.B. and Bayliss-Smith, T.P. (1998). Kelp-plucking: coastal eros ...
'' occur at a number of sites around Heard Island and at least 17 other species of seaweed are known, with more to be added following the identification of recent collections. Low seaweed diversity is due to the island's isolation from other land masses, unsuitable beach habitat, constant abrasion by waves, tides and small stones, and the extension of glaciers into the sea in many areas.
Vegetation communities
Heard Island has a range of terrestrial environments in which vegetation occurs. Seven general vegetation communities are currently recognised, although vegetation composition is considered more of a continuum than discrete units:
* Subantarctic
The sub-Antarctic zone is a region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46° and 60° south of the Equator. The subantarctic region includes many islands ...
vegetation is minimal and includes small types of shrubbery, including mosses and liverworts.
* Open cushionfield vegetation is the most widespread and abundant vegetation type on Heard Island. It is characterised by ''Azorella selago
''Azorella selago'' is a species of cushion plant native to the sub-Antarctic islands of the Southern Ocean, including the Crozet Islands, the Possession Islands, the Heard Island and McDonald Islands, the Kerguelen Islands, and the Prince Edward ...
'' cushions interspersed with bryophytes, small vascular species and bare ground with 20–75% cover, and found mainly at altitudes between 30–70 m asl.
* Fellfield
A fellfield or fell field comprises the environment of a slope, usually alpine or tundra, where the dynamics of frost (freeze and thaw cycles) and of wind give rise to characteristic plant forms in scree interstices.
Soil dynamics
The freeze-thaw ...
describes vegetation with abundant bare ground and less than 50% plant cover. Fellfield may occur as a result of harsh climatic and/or edaphic factors, or recent deglaciation Deglaciation is the transition from full glacial conditions during ice ages, to warm interglacials, characterized by global warming and sea level rise due to change in continental ice volume. Thus, it refers to the retreat of a glacier, an ice shee ...
which has exposed bare ground.
* Moss
Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...
y fellfield
A fellfield or fell field comprises the environment of a slope, usually alpine or tundra, where the dynamics of frost (freeze and thaw cycles) and of wind give rise to characteristic plant forms in scree interstices.
Soil dynamics
The freeze-thaw ...
is a community with high species richness and consists of bryophytes and small ''Azorella selago'' cushions. It is found at altitudes between 30 and 150 m in areas with intermediate exposure.
* Wet mixed herbfield occurs on moist substrate, mostly on moraines and moist lee slopes (often in association with burrowing petrels colonies) at low altitude (< 40 m) where the water table is at or close to the surface. Species richness is highest here of all the communities, with dominant species being ''Poa cookii
''Poa cookii'', sometimes called Cook's tussock-grass or bluegrass, is a species of tussock grass native to various subantarctic islands. The specific epithet honours British explorer James Cook who visited the Kerguelen Islands in 1776.
Desc ...
'', ''Azorella selago'', ''Pringlea antiscorbutica
''Pringlea antiscorbutica'', commonly known as Kerguelen cabbage, is a flowering plant and the sole member of the monotypic genus ''Pringlea'' in the family Brassicaceae. Its common name comes from the archipelago of its discovery, the Kerguelen ...
'', ''Acaena magellanica
''Acaena magellanica'', commonly called buzzy burr or greater burnet, is a species of flowering plant whose range includes the southern tip of South America and many subantarctic islands.
Description
''Acaena magellanica'' is a perennial, mat-f ...
'', and ''Deschampsia antarctica
''Deschampsia antarctica'', the Antarctic hair grass, is one of two flowering plants native to Antarctica, the other being ''Colobanthus quitensis'' (Antarctic pearlwort).
They mainly occur on the South Orkney Islands, the South Shetland Islands ...
''.
* Coastal biotic vegetation is dominated by ''Poa cookii'' and ''Azorella selago'', occurring mainly on coastal sites of moderate exposure and in areas subject to significant influence from seals and seabirds.
* Saltspray vegetation is dominated by the salt-tolerant moss '' Muelleriella crassifolia'' and limited in extent, being found at low elevations on lavas in exposed coastal sites.
* Closed cushionfield is found on moraines and sand at altitudes mostly below 60 m, and is dominated almost entirely by ''Azorella selago'' cushions that often grow together to form continuous carpets which can be subject to burrowing by seabirds.
Outlook
One of the most rapidly changing physical settings in the subantarctic has been produced on Heard Island by a combination of rapid glacial recession and climate warming. The consequent increase in habitat available for plant colonisation, plus the coalescing of previously discrete ice-free areas, has led to marked changes in the vegetation of Heard Island in the last 20 years or so. Other species and vegetation communities found on subantarctic islands north of the Antarctic Convergence
The Antarctic Convergence or Antarctic Polar Front is a marine belt encircling Antarctica, varying in latitude seasonally, where cold, northward-flowing Antarctic waters meet the relatively warmer waters of the sub-Antarctic. Antarctic waters pr ...
now absent from the Heard Island flora may colonise the island if climate change produces more favourable conditions.
Some plant species are spreading and modifying the structure and composition of communities, some of which are also increasing in distribution. It is likely that further changes will occur, and possibly at an accelerated rate. Changes in population numbers of seal and seabird species are also expected to affect the vegetation by changing nutrient availability and disturbance through trampling.
One plant species on Heard Island, ''Poa annua
''Poa annua'', or annual meadow grass (known in America more commonly as annual bluegrass or simply poa), is a widespread low-growing turfgrass in temperate climates. Notwithstanding the reference to annual plant in its name, perennial bio-types ...
'', a cosmopolitan grass native to Europe, was possibly introduced by humans, though is more likely to have arrived naturally, probably by skua
The skuas are a group of predatory seabirds with seven species forming the genus ''Stercorarius'', the only genus in the family Stercorariidae. The three smaller skuas, the long-tailed skua, the Arctic skua, and the pomarine skua are called jae ...
s from the Kerguelen Islands where it is widespread. It was initially recorded in 1987 in two deglaciated areas of Heard Island not previously exposed to human visitors, while being absent from known sites of past human habitation. Since 1987 ''Poa annua'' populations have increased in density and abundance within the original areas and have expanded beyond them. Expeditioner boot traffic during the Australian Antarctic program expedition in 1987 may be at least partly responsible for the spread, but it is probably mainly due to dispersal by wind and the movement of seabirds and seals around the island.
The potential for introducing plant species (including invasive species not previously found on subantarctic islands) by both natural and human-induced means is high. This is due to the combination of low species diversity and climatic amelioration. During the 2003/04 summer a new plant species, ''Cotula plumosa
''Leptinella plumosa'' is a small flowering plant in the Asteraceae, daisy family. It is a Antarctic Circumpolar Current, circumantarctic species found on many subantarctic islands in the Southern Ocean. The specific name (botany), specific ep ...
'', was recorded. Only one small specimen was found growing on a coastal river terrace that had experienced substantial development and expansion of vegetation over the past decade. The species has a circumantarctic distribution and occurs on many subantarctic islands.
Fungi
71 species of lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.[seabird
Seabirds (also known as marine birds) are birds that are 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 enviro ...]
s, seals
Seals may refer to:
* Pinniped, a diverse group of semi-aquatic marine mammals, many of which are commonly called seals, particularly:
** Earless seal, or "true seal"
** Fur seal
* Seal (emblem), a device to impress an emblem, used as a means of a ...
and penguin
Penguins (order (biology), order List of Sphenisciformes by population, Sphenisciformes , family (biology), family Spheniscidae ) are a group of Water bird, aquatic flightless birds. They live almost exclusively in the Southern Hemisphere: on ...
s.
Mammals
Sealing at Heard Island lasted from 1855 to 1910, during which time 67 sealing vessels are recorded visiting, nine of which were wrecked off the coast. Relics that survive from that time include trypots, casks, hut ruins, graves and inscriptions. This caused the seal populations there to either become locally extinct or reduced to levels too low to exploit economically. Modern sealers visited from Cape Town in the 1920s. Since then the populations have generally increased and are protected. Seals breeding on Heard include the southern elephant seal
The southern elephant seal (''Mirounga leonina'') is one of two species of elephant seals. It is the largest member of the clade Pinnipedia and the order Carnivora, as well as the largest extant marine mammal that is not a cetacean. It gets it ...
, the Antarctic fur seal
The Antarctic fur seal (''Arctocephalus gazella''), is one of eight seals in the genus '' Arctocephalus'', and one of nine fur seals in the subfamily Arctocephalinae. Despite what its name suggests, the Antarctic fur seal is mostly distributed i ...
and the subantarctic fur seal
The subantarctic fur seal (''Arctocephalus tropicalis'') is found in the southern parts of the Indian, Pacific, and Atlantic Oceans. It was first described by Gray in 1872 from a specimen recovered in northern Australia—hence the inappropri ...
. Leopard seal
The leopard seal (''Hydrurga leptonyx''), also referred to as the sea leopard, is the second largest species of seal in the Antarctic (after the southern elephant seal). Its only natural predator is the orca. It feeds on a wide range of prey incl ...
s visit regularly in winter to haul-out though they do not breed on the islands. Crabeater, Ross Ross or ROSS may refer to:
People
* Clan Ross, a Highland Scottish clan
* Ross (name), including a list of people with the surname or given name Ross, as well as the meaning
* Earl of Ross, a peerage of Scotland
Places
* RoSS, the Republic of Sou ...
and Weddell seal
The Weddell seal (''Leptonychotes weddellii'') is a relatively large and abundant true seal with a circumpolar distribution surrounding Antarctica. The Weddell seal was discovered and named in the 1820s during expeditions led by British sealing ...
s are occasional visitors.
Birds
Heard Island and the McDonald Islands are free from introduced predators and provide crucial breeding habitat in the middle of the vast Southern Ocean for a range of birds. The surrounding waters are important feeding areas for birds and some scavenging species also derive sustenance from their cohabitants on the islands. The islands have been identified by BirdLife International
BirdLife International is a global partnership of non-governmental organizations that strives to conserve birds and their habitats. BirdLife International's priorities include preventing extinction of bird species, identifying and safeguarding ...
as an Important Bird Area
An Important Bird and Biodiversity Area (IBA) is an area identified using an internationally agreed set of criteria as being globally important for the conservation of bird populations.
IBA was developed and sites are identified by BirdLife Int ...
because they support very large numbers of nesting seabirds.
Nineteen species of birds have been recorded as breeding on Heard Island and the McDonald Islands, although recent volcanic activity at the McDonald Islands in the last decade is likely to have reduced vegetated and un-vegetated nesting areas.[Woehler, E.J. (2006). ‘Status and trends of the seabirds of Heard Island, 2000’, in Heard Island: Southern Ocean Sentinel. ed. Green, K. & Woehler, E. Surrey Beattie.]
Penguins are by far the most abundant birds on the islands, with four breeding species present, comprising king
King is the title given to a male monarch in a variety of contexts. The female equivalent is queen, which title is also given to the consort of a king.
*In the context of prehistory, antiquity and contemporary indigenous peoples, the tit ...
, gentoo, macaroni
Macaroni (, Italian: maccheroni) is dry pasta shaped like narrow tubes.Oxford DictionaryMacaroni/ref> Made with durum wheat, macaroni is commonly cut in short lengths; curved macaroni may be referred to as elbow macaroni. Some home machines ...
and eastern rockhopper penguin
The eastern rockhopper penguin (''Eudyptes chrysocome filholi'') is a crested penguin with yellow crest feathers. It is a subspecies of the southern rockhopper penguin (''Eudyptes chrysocome'') found in subantarctic regions and the Indian Ocean. ...
s. The penguins mostly colonise the coastal tussock and grasslands of Heard Island, and have previously been recorded as occupying the flats and gullies on McDonald Island.
Other seabirds recorded as breeding at Heard Island include three species of albatross ( wandering, black-browed and light-mantled albatross
The light-mantled albatross (''Phoebetria palpebrata'') also known as the grey-mantled albatross or the light-mantled sooty albatross, is a small albatross in the genus ''Phoebetria'', which it shares with the sooty albatross. The light-mantled a ...
es), southern giant petrel
The southern giant petrel (''Macronectes giganteus''), also known as the Antarctic giant petrel, giant fulmar, stinker, and stinkpot, is a large seabird of the southern oceans. Its distribution overlaps broadly with the similar northern giant pet ...
s, Cape petrels, four species of burrowing petrels (Antarctic
The Antarctic ( or , American English also or ; commonly ) is a polar region around Earth's South Pole, opposite the Arctic region around the North Pole. The Antarctic comprises the continent of Antarctica, the Kerguelen Plateau and other ...
and Fulmar prion
The fulmar prion (''Pachyptila crassirostris'') is a species of seabird in the family Procellariidae, found in the southern oceans.
Etymology
Its common name " prion" (not to be confused with the misfolded proteins of the same name) means "saw ...
s, common
Common may refer to:
Places
* Common, a townland in County Tyrone, Northern Ireland
* Boston Common, a central public park in Boston, Massachusetts
* Cambridge Common, common land area in Cambridge, Massachusetts
* Clapham Common, originally com ...
and South Georgia diving petrels), Wilson's storm petrels, kelp gull
The kelp gull (''Larus dominicanus''), also known as the Dominican gull, is a gull that breeds on coasts and islands through much of the Southern Hemisphere. The nominate ''L. d. dominicanus'' is the subspecies found around South America, par ...
s, subantarctic skua
The brown skua (''Stercorarius antarcticus''), also known as the Antarctic skua, subantarctic skua, southern great skua, southern skua, or hākoakoa (Māori), is a large seabird that breeds in the subantarctic and Antarctic zones and moves furth ...
s, Antarctic tern
The Antarctic tern (''Sterna vittata'') is a seabird in the family Laridae. It ranges throughout the southern oceans and is found on small islands around Antarctica as well as on the shores of the mainland. Its diet consists primarily of small fis ...
s and the Heard shag
The Heard Island shag (''Leucocarbo nivalis''), or Heard Island cormorant, is a marine cormorant native to the Australian territory comprising the Heard and McDonald Islands in the Southern Ocean, about 4100 km south-west of Perth, Wester ...
. Although not a true seabird, the Heard Island subspecies of the black-faced sheathbill
The black-faced sheathbill (''Chionis minor''), also known as the lesser sheathbill or paddy bird, is one of only two species of sheathbills, aberrant shorebirds which are terrestrial scavengers of subantarctic islands.
Description
They are du ...
also breeds on the island. Both the shag and the sheathbill are endemic to Heard Island.
A further 28 seabird species are recorded as either non-breeding visitors or have been noted during 'at-sea surveys' of the islands. All recorded breeding species, other than the Heard Island sheathbill, are listed marine species under the Australian Environmental Protection and Biodiversity Act (1999, four are listed as threatened species and five are listed migratory species. Under the EPBC Act a recovery plan has been made for albatrosses and giant petrels, which calls for ongoing population monitoring of the species found at HIMI, and at the time of preparing this plan a draft recovery plan has also been made for the Heard Island cormorant (or shag) and Antarctic tern.
The recorded populations of some seabird species found in the Reserve have shown marked change. The king penguin population is the best studied seabird species on Heard Island and has shown a dramatic increase since first recorded in 1947/48, with the population doubling every five years or so for more than 50 years.
A paper reviewing population data for the black-browed albatross between 1947 and 2000/01 suggested that the breeding population had increased to about three times that present in the late 1940s, although a Convention for the Conservation of Antarctic Marine Living Resources CCAMLR) Working Group was cautious about the interpretation of the increasing trend given the disparate nature of the data, as discussed in the paper. The discovery of a large, previously unknown, colony of Heard shags in 2000/01 at Cape Pillar raised the known breeding population from 200 pairs to over 1000 pairs. The breeding population of southern giant petrels decreased by more than 50% between the early 1950s and the late 1980s.
Terrestrial, freshwater and coastal invertebrates
Heard Island supports a relatively low number of terrestrial invertebrate species compared to other Southern Ocean islands, in parallel with the low species richness in the flora–that is, the island's isolation and limited ice-free area. Endemism
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...
is also generally low and the invertebrate fauna is exceptionally pristine with few, if any, (successful) human-induced introductions of alien species.
Two species, including the thrips ''Apterothrips apteris'' and the mite '' Tyrophagus putrescentiae'' are thought to be recent, possibly natural, introductions. An exotic species of earthworm '' Dendrodrilus rubidus'' was also collected in 1929 from a dump near Atlas Cove, and has recently been collected from a variety of habitats including wallows, streams and lakes on Heard Island.
The arthropods of Heard Island are comparatively well known with 54 species of mite
Mites are small arachnids (eight-legged arthropods). Mites span two large orders of arachnids, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari, but genetic analysis does not show clear evid ...
and tick
Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes. Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". Ticks are external parasites, living by ...
, one spider
Spiders ( order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species ...
and eight springtail
Springtails (Collembola) form the largest of the three lineages of modern hexapods that are no longer considered insects (the other two are the Protura and Diplura). Although the three orders are sometimes grouped together in a class called Ento ...
s recorded. A study over summer at Atlas Cove in 1987/88 showed overall densities of up to 60 000 individual springtails per square metre in soil under stands of ''Pringlea antiscorbutica
''Pringlea antiscorbutica'', commonly known as Kerguelen cabbage, is a flowering plant and the sole member of the monotypic genus ''Pringlea'' in the family Brassicaceae. Its common name comes from the archipelago of its discovery, the Kerguelen ...
''. Despite a few recent surveys, the non-arthropod invertebrate fauna of Heard Island remain poorly known.
Beetles and flies dominate Heard Island's known insect fauna, which comprises up to 21 species of ectoparasite (associated with birds and seals) and up to 13 free-living species. Approximately half of the free-living insects are habitat-specific, while the remainder are generalists found in a variety of habitats, being associated with either supralittoral or intertidal zones, ''Poa cookii
''Poa cookii'', sometimes called Cook's tussock-grass or bluegrass, is a species of tussock grass native to various subantarctic islands. The specific epithet honours British explorer James Cook who visited the Kerguelen Islands in 1776.
Desc ...
'' and ''Pringlea antiscorbutica
''Pringlea antiscorbutica'', commonly known as Kerguelen cabbage, is a flowering plant and the sole member of the monotypic genus ''Pringlea'' in the family Brassicaceae. Its common name comes from the archipelago of its discovery, the Kerguelen ...
'' stands, bryophyte
The Bryophyta s.l. are a proposed taxonomic division containing three groups of non-vascular land plants (embryophytes): the liverworts, hornworts and mosses. Bryophyta s.s. consists of the mosses only. They are characteristically limited in ...
s, lichen-covered rocks, exposed rock faces or the underside of rocks. There is a pronounced seasonality to the insect fauna, with densities in winter months dropping to a small percentage (between 0.75%) of the summer maximum. Distinct differences in relative abundances of species between habitats has also been shown, including a negative relationship between altitude and body size for Heard Island weevils.
The fauna of the freshwater pools, lakes, streams and mires found in the coastal areas of Heard Island are broadly similar to those on other subantarctic islands of the southern Indian Ocean. Many species reported from Heard Island are found elsewhere. Some sampling of freshwater fauna has been undertaken during recent expeditions and records to date indicate that the freshwater fauna includes a species of Protista
A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the excl ...
, a gastrotrich, two species of tardigrade
Tardigrades (), known colloquially as water bears or moss piglets, are a phylum of eight-legged segmented micro-animals. They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them Kleiner Wasserbär ...
, at least four species of nematode, 26 species of rotifer, six species of annelid and 14 species of arthropod.
As with the other shore biota, the marine macro-invertebrate fauna of Heard Island is similar in composition and local distribution to other subantarctic islands, although relatively little is known about the Heard Island communities compared with the well-studied fauna of some other islands in the subantarctic region, such as Macquarie Macquarie may refer to: People
* Lachlan Macquarie, Governor of the British colony of New South Wales from 1810 to 1821.
* Elizabeth Macquarie Campbell, Lachlan Macquarie's second wife
Locations
* Division of Macquarie, an electoral district in th ...
and Kerguelen.
Despite Heard Island's isolation, species richness is considered to be moderate, rather than depauperate, although the number of endemic species reported is low. The large macro-alga ''Durvillaea antarctica
''Durvillaea antarctica'', also known as ' and ', is a large, robust species of southern bull kelp found on the coasts of Chile, southern New Zealand, and Macquarie Island.Smith, J.M.B. and Bayliss-Smith, T.P. (1998). Kelp-plucking: coastal eros ...
'' supports a diverse array of invertebrate taxa and may play an important role in transporting some of this fauna to Heard Island.
The rocky shores of Heard Island exhibit a clear demarcation between fauna of the lower kelp holdfast zone and the upper shore zone community, probably due to effects of desiccation, predation and freezing in the higher areas. The limpet ''Nacella kerguelensis'' is abundant in the lower part of the shore, being found on rock surfaces and on kelp holdfasts. Other common but less abundant species in this habitat include the chiton '' Hemiarthrum setulosum'' and the starfish ''Anasterias mawsoni''. The amphipod ''Hyale'' sp. and the isopod ''Cassidinopsis'' sp. are closely associated with the kelp. Above the kelp holdfast zone, the littornid ''Laevilitorina (Corneolitorina) heardensis'' and the bivalve mollusc ''Kidderia bicolor'' are found in well-sheltered situations, and another bivalve ''Gaimardia trapesina trapesina'' has been recorded from immediately above the holdfast zone. Oligochaetes are also abundant in areas supporting porous and spongy layers of algal mat.
Retreat of Heard Island glaciers
Heard Island is a heavily glaciated, subantarctic volcanic island
Geologically, a high island or volcanic island is an island of volcanic origin. The term can be used to distinguish such islands from low islands, which are formed from sedimentation or the uplifting of coral reefs (which have often formed ...
located in the Southern Ocean
The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica. With a size of , it is regarded as the second-small ...
, roughly southwest of Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
. 80% of the island is covered in ice, with glaciers descending from to sea level
Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardised g ...
. Due to the steep topography
Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the land forms and features themselves, or a description or depiction in maps.
Topography is a field of geoscience and planetary sci ...
of Heard Island, most of its glaciers are relatively thin (averaging only about in depth). The presence of glaciers on Heard Island provides an excellent opportunity to measure the rate of glacial retreat as an indicator of climate change.
Available records show no apparent change in glacier mass balance
Crucial to the survival of a glacier is its mass balance or surface mass balance (SMB), the difference between accumulation and ablation (sublimation and melting). Climate change may cause variations in both temperature and snowfall, causing c ...
between 1874 and 1929. Between 1949 and 1954, marked changes were observed to have occurred in the ice formations above 5000 feet on the southwestern slopes of Big Ben, possibly as a result of volcanic activity. By 1963, major recession was obvious below 2000 feet on almost all glaciers, and minor recession was evident as high as 5000 feet.
The coastal ice cliffs of Brown
Brown is a color. It can be considered a composite color, but it is mainly a darker shade of orange. In the CMYK color model used in printing or painting, brown is usually made by combining the colors orange and black. In the RGB color model used ...
and Stephenson Glaciers, which in 1954 were over 50 feet high, had disappeared by 1963 when the glaciers terminated as much as 100 yards inland.[ Baudissin Glacier on the north coast, and ]Vahsel Glacier
Vahsel Glacier () is a glacier on the northwestern side of Heard Island in the southern Indian Ocean. It flows west into South West Bay, between Erratic Point and Cape Gazert. Immediately to the north of Vahsel Glacier is Schmidt Glacier, whose t ...
on the west coast have lost at least 100 and 200 vertical feet of ice, respectively.[ Winston Glacier, which retreated approximately one mile between 1947 and 1963, appears to be a very sensitive indicator of glacier change on the island. The young moraines flanking Winston Lagoon show that Winston Glacier has lost at least 300 vertical feet of ice within a recent time period.][ ]Jacka Glacier
Jacka Glacier () is a long glacier which flows northeast from Hayter Peak and terminates in icefalls opposite Vanhoffen Bluff on the north side of Heard Island in the southern Indian Ocean. The glacier appears to be roughly charted on an 1860 s ...
on the east coast of Laurens Peninsula Laurens Peninsula () is a rugged peninsula surmounted by several ice-covered peaks that forms the northwestern part of Heard Island in the southern Indian Ocean. The name was applied by the Australian National Antarctic Research Expedition following ...
has also demonstrated marked recession since 1955.[
Retreat of glacier fronts across Heard Island is evident when comparing ]aerial photograph
Aerial photography (or airborne imagery) is the taking of photographs from an aircraft or other airborne platforms. When taking motion pictures, it is also known as aerial videography.
Platforms for aerial photography include fixed-wing ai ...
s taken in December 1947 with those taken on a return visit in early 1980. Retreat of Heard Island glaciers is most dramatic on the eastern section of the island, where the termini of former tidewater glacier
The tidewater glacier cycle is the typically centuries-long behavior of tidewater glaciers that consists of recurring periods of advance alternating with rapid retreat and punctuated by periods of stability. During portions of its cycle, a tidewate ...
s are now located inland.[ Glaciers on the northern and western coasts have narrowed significantly, while the area of glaciers and ]ice cap
In glaciology, an ice cap is a mass of ice that covers less than of land area (usually covering a highland area). Larger ice masses covering more than are termed ice sheets.
Description
Ice caps are not constrained by topographical features ...
s on Laurens Peninsula have shrunk by 30–65%.[
During the time period between 1947 and 1988, the total area of Heard Island's glaciers decreased by 11%, from (roughly 79% of the total area of Heard Island) to only .][ A visit to the island in the spring of 2000 found that the Stephenson, Brown and Baudissin glaciers, among others, had retreated even further.][ The terminus of Brown Glacier has retreated approximately since 1950.][ The total ice-covered area of Brown Glacier is estimated to have decreased by roughly 29% between 1947 and 2004.][ This degree of loss of glacier mass is consistent with the measured increase in temperature of over that time span.][
Possible causes of glacier recession on Heard Island include:
#Volcanic activity
#Southward movement of the ]Antarctic Convergence
The Antarctic Convergence or Antarctic Polar Front is a marine belt encircling Antarctica, varying in latitude seasonally, where cold, northward-flowing Antarctic waters meet the relatively warmer waters of the sub-Antarctic. Antarctic waters pr ...
: such a movement conceivably might cause glacier retreat through a rise in sea and air temperatures
#Climatic change
The Australian Antarctic Division
The Australian Antarctic Division (AAD) is a division of the Department of Climate Change, Energy, the Environment and Water. The Division undertakes science programs and research projects to contribute to an understanding of Antarctica and the ...
conducted an expedition to Heard Island during the austral summer
Summer is the hottest of the four temperate seasons, occurring after spring and before autumn. At or centred on the summer solstice, the earliest sunrise and latest sunset occurs, daylight hours are longest and dark hours are shortest, with ...
of 2003–04. A small team of scientists spent two months on the island, conducting studies on avian
Avian may refer to:
*Birds or Aves, winged animals
*Avian (given name) (russian: Авиа́н, link=no), a male forename
Aviation
*Avro Avian, a series of light aircraft made by Avro in the 1920s and 1930s
*Avian Limited, a hang glider manufacture ...
and terrestrial biology and glaciology
Glaciology (; ) is the scientific study of glaciers, or more generally ice and natural phenomena that involve ice.
Glaciology is an interdisciplinary Earth science that integrates geophysics, geology, physical geography, geomorphology, climato ...
. Glaciologists conducted further research on the Brown Glacier, in an effort to determine whether glacial retreat is rapid or punctuated. Using a portable echo sounder
Echo sounding or depth sounding is the use of sonar for ranging, normally to determine the depth of water (bathymetry). It involves transmitting acoustic waves into water and recording the time interval between emission and return of a pulse; ...
, the team took measurements of the volume of the glacier. Monitoring of climatic conditions continued, with an emphasis on the impact of Foehn wind
A Foehn or Föhn (, , ), is a type of dry, relatively warm, downslope wind that occurs in the lee (downwind side) of a mountain range.
It is a rain shadow wind that results from the subsequent adiabatic warming of air that has dropped most of ...
s on glacier mass balance. Based on the findings of that expedition, the rate of loss of glacier ice on Heard Island appears to be accelerating. Between 2000 and 2003, repeat GPS
The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...
surface surveys revealed that the rate of loss of ice in both the ablation zone
Ablation zone or ''ablation area'' refers to the low-altitude area of a glacier or ice sheet below firn with a net loss in ice mass due to melting, sublimation, evaporation, ice calving, aeolian processes like blowing snow, avalanche, and any oth ...
and the accumulation zone
On a glacier, the accumulation zone is the area above the firn line, where snowfall accumulates and exceeds the losses from ablation, (melting, evaporation, and sublimation). The annual equilibrium line separates the accumulation and ablation zo ...
of Brown Glacier was more than double average rate measured from 1947 to 2003. The increase in the rate of ice loss suggests that the glaciers of Heard Island are reacting to ongoing climate change, rather than approaching dynamic equilibrium
In chemistry, a dynamic equilibrium exists once a reversible reaction occurs. Substances transition between the reactants and products at equal rates, meaning there is no net change. Reactants and products are formed at such a rate that the conc ...
.[ The retreat of Heard Island's glaciers is expected to continue for the foreseeable future.][
]
Administration and economy
The United Kingdom formally established its claim to Heard Island in 1910, marked by the raising of the Union Flag and the erection of a beacon by Captain Evensen, master of the ''Mangoro''. Effective government, administration and control of Heard Island and the McDonald Islands was transferred to the Australian government on 26 December 1947 at the commencement of the first Australian National Antarctic Research Expedition
The Australian National Antarctic Research Expeditions (ANARE ) is the historical name for the Australian Antarctic Program (AAp) administered for Australia by the Australian Antarctic Division (AAD).
History
Australia has had a long involv ...
(ANARE) to Heard Island, with a formal declaration that took place at Atlas Cove. The transfer was confirmed by an exchange of letters between the two governments on 19 December 1950.
The islands are a territory (Territory of Heard Island and McDonald Islands) of Australia administered from Hobart
Hobart ( ; Nuennonne/Palawa kani: ''nipaluna'') is the capital and most populous city of the Australian island state of Tasmania. Home to almost half of all Tasmanians, it is the least-populated Australian state capital city, and second-small ...
by the Australian Antarctic Division
The Australian Antarctic Division (AAD) is a division of the Department of Climate Change, Energy, the Environment and Water. The Division undertakes science programs and research projects to contribute to an understanding of Antarctica and the ...
of the Australian Department of the Environment and Energy
The Department of the Environment and Energy (DEE) was an Australian government department in existence between 2016 and 2020.
The department was responsible for matters including environment protection and conservation of biodiversity as well ...
. The administration of the territory is established in the ''Heard Island and McDonald Islands Act 1953'', which places it under the laws of the Australian Capital Territory
The Australian Capital Territory (commonly abbreviated as ACT), known as the Federal Capital Territory (FCT) until 1938, is a landlocked federal territory of Australia containing the national capital Canberra and some surrounding townships. ...
and the jurisdiction of the Supreme Court of the Australian Capital Territory
The Supreme Court of the Australian Capital Territory is the highest court of the Australian Capital Territory (ACT). It has unlimited jurisdiction within the territory in Civil law (common law), civil matters and hears the most serious Criminal ...
. The islands are contained within a marine reserve and are primarily visited for research, meaning that there is no permanent human habitation.
From 1947 until 1955 there were camps of visiting scientists on Heard Island (at Atlas Cove in the northwest, which was in 1969 again occupied by American scientists and expanded in 1971 by French scientists) and in 1971 on McDonald Island (at Williams Bay
Williams Bay is a village in Walworth County, Wisconsin, United States. It is one of three municipalities on Geneva Lake. The population was 2,564 at the 2010 census.
History
The village was named for Captain Israel Williams of Massachusett ...
). Later expeditions used a temporary base at Spit Bay
Spit Bay () is an open Bight (geography), bight formed by the northeast coastline of Heard Island and Spit Point, the east extremity of the island. The name derives from the conspicuous Elephant Spit which forms the south and east shore of the bigh ...
in the east, such as in 1988, 1992–93 and 2004–05.
The islands' only natural resource is fish; the Australian government allows limited fishing in the surrounding waters. Despite the lack of population, the islands have been assigned the country code
Country codes are short alphabetic or numeric geographical codes (geocodes) developed to represent countries and dependent areas, for use in data processing and communications. Several different systems have been developed to do this. The term '' ...
HM in ISO 3166-1
ISO 3166-1 (''Codes for the representation of names of countries and their subdivisions – Part 1: Country codes'') is a standard defining codes for the names of countries, dependent territories, and special areas of geographical interest. It ...
( ISO 3166-2:HM) and therefore the Internet top-level domain
A top-level domain (TLD) is one of the domains at the highest level in the hierarchical Domain Name System of the Internet after the root domain. The top-level domain names are installed in the root zone of the name space. For all domains in ...
.hm
.hm is the Internet country code top-level domain ( ccTLD) of the Heard and McDonald Islands, uninhabited islands in the southern Indian Ocean under the sovereign control of Australia. Although .hm gets a small amount of use, Australia uses the ...
. The time zone of the islands is UTC+5.
See also
* Australian Antarctic Territory
The Australian Antarctic Territory (AAT) is a part of East Antarctica claimed by Australia as an external territory. It is administered by the Australian Antarctic Division, an agency of the federal Department of Climate Change, Energy, the Env ...
* List of Antarctic and sub-Antarctic islands
* List of birds of Heard and McDonald Islands
This is a list of the birds of Heard Island and the adjacent McDonald Islands in the southern Indian Ocean. For other animals there, see List of non-avian fauna of Heard Island and McDonald Islands.
The avifauna of Antarctica include a total o ...
* List of glaciers in the Antarctic
There are many glaciers in the Antarctic. This set of lists does not include ice sheets, ice caps or ice fields, such as the Antarctic ice sheet, but includes glacial features that are defined by their flow, rather than general bodies of ice. Th ...
* List of islands of Australia
This is a list of selected Australian islands grouped by State or Territory. Australia has 8,222 islands within its maritime borders.
Largest islands
The islands larger than are:
* Tasmania (Tas) ;
* Melville Island, Northern Territory (NT ...
* Needle Island
* Retreat of glaciers since 1850
The retreat of glaciers since 1850 affects the availability of fresh water for irrigation and domestic use, mountain recreation, animals and plants that depend on glacier-melt, and, in the longer term, the level of the oceans. Deglaciation occu ...
* Sunken Rock
* Wakefield Reef Wakefield Reef () is a reef, 0.5 nautical miles (0.9 km) across, lying 2.5 nautical miles (4.6 km) west-southwest of Cape Arkona, off the southwest side of Heard Island. The existence of a reef in this area is noted on an unpubl ...
References
Further reading
* Commonwealth of Australia (2014). ''Heard Island and McDonald Islands Marine Reserve Management Plan 2014–2024'', Department of the Environment, Canberra. . Available at http://heardisland.antarctica.gov.au/
* Australian Government. (2005) ''Heard Island and McDonald Islands Marine Reserve Management Plan''. Australian Antarctic Division: Kingston (Tas). .
* Green, Ken and Woehler Eric (eds). (2006) ''Heard Island: Southern Ocean Sentinel''. Chipping Norton: Surrey Beatty and Sons. .
* Scholes, Arthur. (1949) ''Fourteen men; story of the Australian Antarctic Expedition to Heard Island''. Melbourne: F.W. Cheshire.
* Smith, Jeremy. (1986) ''Specks in the Southern Ocean''. Armidale: University of New England Press. .
* LeMasurier, W. E. and Thomson, J. W. (eds.). (1990) ''Volcanoes of the Antarctic Plate and Southern Oceans''. American Geophysical Union
The American Geophysical Union (AGU) is a 501(c)(3) nonprofit organization of Earth, atmospheric, ocean, hydrologic, space, and planetary scientists and enthusiasts that according to their website includes 130,000 people (not members). AGU's act ...
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External links
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Map of Heard Island and McDonald Islands
including all major topographical features
World heritage listing for Heard Island and McDonald Islands
Heard Island and McDonald Islands
''The World Factbook
''The World Factbook'', also known as the ''CIA World Factbook'', is a reference resource produced by the Central Intelligence Agency (CIA) with almanac-style information about the countries of the world. The official print version is available ...
''. Central Intelligence Agency
The Central Intelligence Agency (CIA ), known informally as the Agency and historically as the Company, is a civilian foreign intelligence service of the federal government of the United States, officially tasked with gathering, processing, ...
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Image gallery
of Heard Island and McDonald Island with high quality limited copyright images.
UNESCO World Heritage site entry
* with further historical and geographic information and a map
Heard Island: The Cordell Expedition 2016
{{Authority control
Islands of Australia
States and territories established in 1947
Australian National Heritage List
Seal hunting
Important Bird Areas of Australian External Territories
IBRA subregions
World Heritage Sites in Australia
Important Bird Areas of Indian Ocean islands
Heard Island
The Territory of Heard Island and McDonald Islands (HIMI) is an Australian external territory comprising a volcanic group of mostly barren Antarctic islands, about two-thirds of the way from Madagascar to Antarctica. The group's overall size ...