Williams Island is an
island 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 ...
of
South Australia located off the south coast of
Jussieu Peninsula on
Eyre Peninsula approximately south-east of
Port Lincoln. It was named by
Matthew Flinders
Captain Matthew Flinders (16 March 1774 – 19 July 1814) was a British navigator and cartographer who led the first inshore circumnavigation of mainland Australia, then called New Holland. He is also credited as being the first person to u ...
for Robert Williams who subsequently lost his life along with seven other crew in the capsize of a
cutter
Cutter may refer to:
Tools
* Bolt cutter
* Box cutter, aka Stanley knife, a form of utility knife
* Cigar cutter
* Cookie cutter
* Glass cutter
* Meat cutter
* Milling cutter
* Paper cutter
* Side cutter
* Cutter, a type of hydraulic rescue to ...
launched from
HM Sloop ''Investigator'' to search for water on 21 February 1802. Since 2004, the island has been part of the
Memory Cove Wilderness Protection Area.
Description
Williams Island which is approximately south-east of Port Lincoln and south-south-east of West Point on the Jussieu Peninsula is broadly a U-shaped island with a maximum height of and an area of . While the island is bordered by cliffs, a bay with a sandy beach on its north coast provides both a sheltered anchorage for most wind directions and a point of access to the island.
Formation, geology and oceanography
Williams Island was formed about 9,100 years ago when sea levels began to rise at the start of the
Holocene.
The island's geological structure consists of an upper platform of
calcarenite laying over on "a U-shaped ridge of
pink granite, dark coloured
porphyritic
Porphyritic is an adjective used in geology to describe igneous rocks with a distinct difference in the size of mineral crystals, with the larger crystals known as phenocrysts. Both extrusive and intrusive rocks can be porphyritic, meaning all ...
granite
gneiss with intrusions by large, dark
dolerite dykes."
[ The open end of the "U" aligns with the island's northern coast. The U-shaped ridge is visible as an "encircling wall of steep cliffs and talus slopes" over which the "calcarenite platform starts as a talus slope of fractured rock and scree or as low cliffs and overhangs" thickens into "a thick layer of soil" covering most of the island.][
The island rises from the sea floor at approximately over a distance of approximately to .]
Flora and fauna
Terrestrial plants
As of 1996, a total of 26 plant species was reported as being present. The island's upper platform is dominated by a shrubland
Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It m ...
of saltbush, dominated by marsh saltbush and grey saltbush
''Atriplex cinerea'', commonly known as grey saltbush, coast saltbush, barilla or ''truganini'', is a plant species in the family Amaranthaceae. It occurs in sheltered coastal areas and around salt lakes in the Australian states of Western Aust ...
while herbfield
Herbfields are plant communities dominated by herbaceous plants, especially forbs and grasses. They are found where climatic conditions do not allow large woody plants to grow, such as in subantarctic and alpine tundra environments. Herbfield is ...
s dominated by austral storksbill are present on low granite outcrops at several locations near the island's south east tip where the underlying granite strata has passed through the island’s calcareous topping.[ Visitors to the island in 1907 described the island as treeless, but supporting "low, stunted saltbush".]
Terrestrial animals
An account from a 1907 expedition including Sir Douglas Mawson described the island as teeming with snakes, and noted the presence of a large, badly scarred bull seal. As of 1996, a total of one mammal, 11 bird and three reptile species were reported as being present on the island. Of particular note, is the bush rat, the black tiger snake which predates on the bush rat population and short-tailed shearwater
The short-tailed shearwater or slender-billed shearwater (''Ardenna tenuirostris''; formerly ''Puffinus tenuirostris''), also called yolla or moonbird, and commonly known as the muttonbird in Australia, is the most abundant seabird species in A ...
s which are reported as using the island as a breeding colony.[ As of 2013, the island is reported as being an unconfirmed breeding site for flesh-footed shearwaters.]
History
The island was first sighted by Europeans on 20 February 1802 from HMS ''Investigator'' whilst under the command of Matthew Flinders and was named on that day after seaman Robert Williams. Williams subsequently lost his life, presumably drowned, along with seven other members of the crew on 21 February 1802 when one of HMS ''Investigator''s cutters
Cutter may refer to:
Tools
* Bolt cutter
* Box cutter, aka Stanley knife, a form of utility knife
* Cigar cutter
* Cookie cutter
* Glass cutter
* Meat cutter
* Milling cutter
* Paper cutter
* Side cutter
* Cutter, a type of hydraulic rescue to ...
capsized near Cape Catastrophe. The island was surveyed by Thomas Lipson
Captain Thomas Lipson (ca.1784 – 25 October 1863) was an officer in the Royal Navy, who, after a successful if unspectacular career in the Royal Navy, was appointed by the Admiralty as the first Harbourmaster, Harbour Master at South Australia, ...
, RN in 1840 as part of an ongoing South Australian Government program to map the colony’s waters, identify shipping hazards and assess the suitability of the coastline for settlement.
Navigation aids
A navigation aid consisting of a tower with a single flashing light was located on the west side of the island since 1963. An area of land of approximately in size is reserved for use by the responsible government agency, the Australian Maritime Safety Authority (AMSA). Access to the Island for the maintenance of the navigation aid is via helicopter.
Economic activity
Gauno
Williams Island is one of the island sites from which guano
Guano (Spanish from qu, wanu) is the accumulated excrement of seabirds or bats. As a manure, guano is a highly effective fertilizer due to the high content of nitrogen, phosphate, and potassium, all key nutrients essential for plant growth. G ...
was mined under licence from the South Australian Government prior to 1919.
Protected area status
Since 30 September 2004, Williams Island has been part of the Memory Cove Wilderness Protection Area. Previously, it had been part of the Lincoln National Park
Lincoln National Park is a protected area in the Australian state of South Australia located about west of the state capital of Adelaide and about south of the municipal seat of Port Lincoln. It consists of a mainland area on the Jussieu Pe ...
.
References
{{DEFAULTSORT:Williams Island(South Australia)
Islands of South Australia
Uninhabited islands of Australia
Great Australian Bight