The Spencer Gulf Shelf Province, also known as the South Australian Gulfs

marine ecoregion A marine ecoregion is an ecoregion, or ecological region, of the oceans and seas identified and defined based on biogeographic characteristics. Introduction A more complete definition describes them as “Areas of relatively homogeneous species ...

, is a

biogeographic Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time. Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, ...

region of

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

continental shelf A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an islan ...

and coastal waters. It includes the warm temperate coastal waters of

South Australia South Australia (commonly abbreviated as SA) is a States and territories of Australia, state in the southern central part of Australia. With a total land area of , it is the fourth-largest of Australia's states and territories by area, which in ...

's central coast. It is a provincial bioregion in the

Integrated Marine and Coastal Regionalisation of Australia The Integrated Marine and Coastal Regionalisation of Australia (IMCRA), formerly the Interim Marine and Coastal Regionalisation for Australia, is a biogeographic regionalisation of the oceanic waters of Australia's exclusive economic zone (EEZ ...

(IMCRA) system."A Guide to the Integrated Marine and Coastal Regionalisation of Australia Version 4.0". Department of Environment and Heritage, Government of Australia. June 2006. .

Geography

The Spencer Gulf Shelf Province includes the warm temperate coastal waters and continental shelf of the eastern

Great Australian Bight The Great Australian Bight is a large oceanic bight (geography), bight, or open bay, off the central and western portions of the southern Coast, coastline of mainland Australia. There are two definitions for its extent—one by the Internation ...

Spencer Gulf The Spencer Gulf is the westernmost and larger of two large inlets (the other being Gulf St Vincent) on the southern coast of Australia, in the state of South Australia, facing the Great Australian Bight. It spans from the Cape Catastrophe an ...

and St Vincent Gulf, the waters around

Kangaroo Island Kangaroo Island (, ) is Australia's third-largest island, after Tasmania and Melville Island, Northern Territory, Melville Island. It lies in the state of South Australia, southwest of Adelaide. Its closest point to the mainland is Snapper Poi ...

, and the Coorong coast. It extends from Point Brown in the west to

Cape Jaffa Cape Jaffa is a headland in the Australian state of South Australia located at the south end of Lacepede Bay on the state's south east coast about south west of the town centre of Kingston SE. The cape is described as being "a low sandy poin ...

in the east, and out to the edge of the continental shelf. It bounded on the west by the

Great Australian Bight Shelf Transition The Great Australian Bight is a large oceanic bight, or open bay, off the central and western portions of the southern coastline of mainland Australia. There are two definitions for its extent—one by the International Hydrographic Organizati ...

, and to the east by the Western Bass Strait Shelf Transition. The bioregion is influenced by the warm

Leeuwin Current The Leeuwin Current is a warm ocean current which flows southwards near the western coast of Australia. It rounds Cape Leeuwin to enter the waters south of Australia where its influence extends as far as Tasmania. Discovery The existence of the ...

, which runs eastwards along the coast. Stretches of coast facing the open ocean, particularly along the west coast of the

Eyre Peninsula The Eyre Peninsula is a triangular peninsula in South Australia. It is bounded by the Spencer Gulf on the east, the Great Australian Bight on the west, and the Gawler Ranges to the north. Earlier called Eyre's Peninsula, it was named after e ...

and at the 'Kangaroo Island Pool' south of Kangaroo Island, experience cold-water

upwelling Upwelling is an physical oceanography, oceanographic phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water from deep water towards the ocean surface. It replaces the warmer and usually nutrient-depleted sur ...

during the summer months, known as the

Great South Australian Coastal Upwelling System The Great South Australian Coastal Upwelling System is a seasonal upwelling system in the eastern Great Australian Bight, extending from Ceduna, South Australia, to Portland, Victoria, over a distance of about . Upwelling events occur in the aus ...

. The Spencer and St Vincent gulfs are largely enclosed by semi-arid land with little freshwater inflow, resulting in hypersaline waters and subtropical water temperatures.

Meso-scale bioregions

The IMCRA identifies five meso-scale bioregions that make up the province: * Coorong (COR),

Cape Jervis Cape Jervis is a town in the Australian state of South Australia located near the western tip of Fleurieu Peninsula on the southern end of the Main South Road approximately south of the state capital of Adelaide. It is named after the headla ...

. * Eyre (EYR), Point Brown to Cape Torrens, to

West Cape West Cape is the westernmost point in the main chain of islands of New Zealand. It is located in the far southwest of the South Island, within Fiordland National Park, between Tamatea / Dusky Sound and Taiari / Chalky Inlet. The cape consists ...

, to

Port Neill Port Neill (formerly Carrow) is a small coastal town on the eastern side of the Eyre Peninsula, in South Australia about 3 km off the Lincoln Highway between the major towns of Whyalla and Port Lincoln. It is 576 km by road from Adelaid ...

and

Cape Willoughby Cape Willoughby is a headland in the Australian state of South Australia located on the east end of the Dudley Peninsula on Kangaroo Island in the gazetted locality of Willoughby about south east of the town of Penneshaw. The cape is describe ...

. * North Spencer Gulf (NSG), extends from Point Riley to

Port Augusta Port Augusta (''Goordnada'' in the revived indigenous Barngarla language) is a coastal city in South Australia about by road from the state capital, Adelaide. Most of the city is on the eastern shores of Spencer Gulf, immediately south of the ...

to Shoalwater Point. * St Vincent Gulf (SVG), extends from Cape Torrens to West Cape, Cape Jervis to Cape Willoughby. * Spencer Gulf (SG),

to Port Neill, Point Riley to Shoalwater Point. In version 3.3 of the IMCRA, the province was known as Gulfs Province, and Coorong bioregion was included in the neighboring Western Bass Strait Shelf Transition. Version 4.0 renamed the province Spencer Gulf Shelf and added Coorong.

Ecology

The biota of the province is characterised by warm temperate species, many of which range westwards across the Bight into Southwest Australia. Some cool-temperate species characteristic of the Bass Strait and Tasmania reach the western extent of their range here. The gulfs, which are hypersaline and warmer than the surrounding waters, are refugia for some subtropical and endemic species.

New Zealand fur seal ''Arctocephalus forsteri'' (common names include the Australasian fur seal, South Australian fur seal, New Zealand fur seal, Antipodean fur seal, or long-nosed fur seal) is a species of fur seal found mainly around southern Australia and New Z ...

s (''Arctocephalus forsteri'') feed on pelagic fish near the shelf break, and have breeding colonies on the

Neptune Islands The Neptune Islands consist of two groups of islands located close to the entrance to Spencer Gulf in South Australia. They are well known as a venue for great white shark tourism. Description The Neptune Islands consists of two groups of isla ...

and Liguanea Island.

Australian sea lion The Australian sea lion (''Neophoca cinerea''), also known as the Australian sea-lion or Australian sealion, is a species of sea lion that is the only endemic pinniped in Australia. It is currently Monotypic taxon, monotypic in the genus ''Neopho ...

s (''Neophoca cinerea'') have breeding colonies on Little Waldegrave Island, Olive Island, Seal Bay on Kangaroo Island, and

Dangerous Reef Dangerous Reef is an island and reef system located in the Spencer Gulf in the Australian state of South Australia about east-southeast of the city, Port Lincoln. It is the southernmost member of the Sir Joseph Banks Group. It has been the sit ...

in Spencer Gulf. The seasonal upwelling of nutrient-rich water along the western Eyre Peninsula and at the Kangaroo Island Pool nurtures plankton,

krill Krill ''(Euphausiids)'' (: krill) are small and exclusively marine crustaceans of the order (biology), order Euphausiacea, found in all of the world's oceans. The name "krill" comes from the Norwegian language, Norwegian word ', meaning "small ...

, and fish, which provide food for dolphins,

Australian little penguin The Australian little penguin (''Eudyptula novaehollandiae''), also called the fairy penguin, little blue penguin, or blue penguin, is a species of penguin from Australia and the Otago region of New Zealand. The species was described as ''Sph ...

s (''Eudyptula novaehollandiae''), and

blue whale The blue whale (''Balaenoptera musculus'') is a marine mammal and a baleen whale. Reaching a maximum confirmed length of and weighing up to , it is the largest animal known ever to have existed. The blue whale's long and slender body can ...

s (''Balaenoptera musculus'').''The South-west Marine Bioregional Plan: Bioregional Profile''. Department of the Environment, Water, Heritage and the Arts, Australian Government, 2007.

References

{{reflist Biogeography of South Australia Ecoregions of Australia Marine ecoregions IMCRA provincial bioregions Temperate Australasia Coastline of South Australia