South Island (also called Peter Island, South Islet and West Bay Island) is an

island An island (or isle) is an isolated piece of habitat that is surrounded by a dramatically different habitat, such as water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island ...

located in the

Australian state The states and territories are federated administrative divisions in Australia, ruled by regional governments that constitute the second level of governance between the federal government and local governments. States are self-governing ...

South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...

at the south end of Pondalowie Bay on the south-west extremity of

Yorke Peninsula The Yorke Peninsula is a peninsula located northwest and west of Adelaide in South Australia, between Spencer Gulf on the west and Gulf St Vincent on the east. The peninsula is separated from Kangaroo Island to the south by Investigator Str ...

about north-west by west of the town of Stenhouse Bay. The island has enjoyed protected area status since 1970 and since 1977, it has been part of the Innes National Park.

Description

South Island is an island located on the south-west extremity of the Yorke Peninsula in South Australia at the southern end of Pondalowie Bay about north-west by west of the town of Stenhouse Bay.DMH, 1985, charts 22 & 23 The island has “sheer cliffs” on its exposed north and west coasts where a maximum elevation of exists while its relatively protected east and south coasts have “low cliffs and ledges” created by swells diffracted within the bay. The island is connected to the mainland by a “neck of drying rock and sand” which does allow access by fauna.Robinson et al, 1996, pages 284-285

Formation, geology and oceanography

South Island was formed about 6000 years ago following the rise of sea levels at the start of the

Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togeth ...

.Robinson et al, 1996, page 285 South Island consists of a

calcarenite Calcarenite is a type of limestone that is composed predominantly, more than 50 percent, of detrital (transported) sand-size (0.0625 to 2 mm in diameter), carbonate grains. The grains consist of sand-size grains of either corals, shells, ooi ...

layer over a

granite Granite () is a coarse-grained ( phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies under ...

base. South Island is the permanently exposed part of a submerged reef system extending from the southern headland of Pondalowie Bay.

Flora and fauna

Flora

A survey carried out during 1982 on South Island found that its vegetation consisted of two groups defined by exposure to the weather, sea spray and amount of available soil. The western half of the island is occupied by a "low, open

heath A heath () is a shrubland habitat found mainly on free-draining infertile, acidic soils and characterised by open, low-growing woody vegetation. Moorland is generally related to high-ground heaths with—especially in Great Britain—a cooler a ...

” that “clings to any soil-filled hollow and crack” and includes plant tolerant of a “saline rocky coastal or island environment” such as round-leaved pigface, creeping brookweed,

marsh saltbush ''Atriplex paludosa'', commonly known as marsh saltbush, is a species of saltbush endemic to Australia. Description It grows as an erect shrub up to a metre high. Leaves are oval in shape, one to four centimetres long, and 2 to 15 millimetres wi ...

, southern sea heath and

bassia ''Bassia'' is a genus of flowering plants in the family Amaranthaceae. They are distributed in the western Mediterranean to eastern Asia. Some occur outside their native ranges as introduced species.bower spinach ''Tetragonia implexicoma'', commonly known as bower spinach, is a species of plant in the Aizoaceae, or ice-plant family (biology), family. A similar species is ''Tetragonia tetragonioides'', however this species has larger leaves and a shorter f ...

, coast beard-heath, coast daisy-bush, coast velvet-bush, cockies tongue, clustered swordsedge, common correa, dryland teatree, feather spear-grass, hills daisy, leafless cherry, native juniper, pleated podolepis, Port Lincoln wattle, cushion fanflower, thyme riceflower, slender dodder-laurel and

variable groundsel ''Senecio pinnatifolius'' is a species of herb native to Australia. Common names include coast groundsel, dune groundsel and variable groundsel. Description It grows as an erect herb up to a metre in height, with yellow flowers. Taxonomy The na ...

Fauna

Vertebrate animals are represented by mammals and birds. A survey carried in 1982 noted evidence that

kangaroo Kangaroos are four marsupials from the family Macropodidae (macropods, meaning "large foot"). In common use the term is used to describe the largest species from this family, the red kangaroo, as well as the antilopine kangaroo, eastern ...

s had accessed the island from the mainland at low tide. In 1982, the following bird species were observed -

osprey The osprey (''Pandion haliaetus''), , also called sea hawk, river hawk, and fish hawk, is a diurnal, fish-eating bird of prey with a cosmopolitan range. It is a large raptor reaching more than in length and across the wings. It is brown o ...

Pacific gull The Pacific gull (''Larus pacificus'') 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 re ...

silver gull The silver gull (''Chroicocephalus novaehollandiae'') is the most common gull of Australia. It has been found throughout the continent, but particularly at or near coastal areas. It is smaller than the Pacific gull (''Larus pacificus''), which ...

and

welcome swallow The welcome swallow (''Hirundo neoxena'') is a small passerine bird in the swallow family. It is a species native to Australia and nearby islands, and self-introduced into New Zealand in the middle of the twentieth century. It is very similar ...

History

Aboriginal use

As South Island has been historically accessible by foot at low water, it has been suggested in the literature that local Aboriginal people may have used the island to trap kangaroos to use as a source of food.

European use

The island is reported in various sources as being named as Peter Island, South Island, South Islet and West Bay Island. A

navigation aid Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, ...

consisting of an automatic light which is operated by the

Australian Maritime Safety Authority Australian Maritime Safety Authority (AMSA) is an Australian statutory authority responsible for the regulation and safety oversight of Australia's shipping fleet and management of Australia's international maritime obligations. The authority ...

is located at the island’s north-west coast.

Protected areas status

South Island was part of a parcel of land declared as a fauna reserve under the ''Fauna Conservation Act 1964'' on 26 November 1970. It was subsequently declared as part of the Innes National Park as part of another parcel of land on 2 June 1977 while the waters adjoining its shoreline have been located within a habitat protection zone in the South Spencer Gulf Marine Park since 2012.DEWNR, 2012, page 24 Since at least 2014, South Island and the other two islands in Pondalowie Bay (from north to south),

Royston Island Royston Island (also known as North Island) is an island in the Australian state of South Australia at the northern end of Pondalowie Bay on the south-west extremity of Yorke Peninsula about north-west of the town of Stenhouse Bay. The isla ...

and Middle Island, have been closed to access by visitors to the national park.DEWNR, 2014

Citations and references

Citations

References

* * * * * {{DEFAULTSORT:South Island (South Australia)) Islands of South Australia Uninhabited islands of Australia Spencer Gulf Yorke Peninsula