Williams Island (South Australia)

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Williams Island
Williams Island (South Australia) is located in South Australia
Williams Island (South Australia)
Geography
Location Great Australian Bight
Coordinates 35°01′50″S 135°58′30″E / 35.03056°S 135.97500°E / -35.03056; 135.97500Coordinates: 35°01′50″S 135°58′30″E / 35.03056°S 135.97500°E / -35.03056; 135.97500
Country

Williams Island is an island located off the south coast of Jussieu Peninsula on Eyre Peninsula in South Australia approximately 34 km (21 mi) south-east of Port Lincoln. It was named by Matthew Flinders for Robert Williams who subsequently lost his life along with seven other crew in the capsize of a cutter launched from the 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[edit]

Williams Island which is approximately 34 km (21 mi) south-east of Port Lincoln and 1.8 km (1.1 mi) south-south-east of West Point on the Jussieu Peninsula is broadly a U-shaped island with a maximum height of 40 m (130 ft) and an area of 141 ha (350 acres). 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.[1][2]

Formation, geology and oceanography[edit]

Williams Island was formed about 9100 years ago when sea levels began to rise at the start of the Holocene.[3]

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 granite gneiss with intrusions by large, dark dolerite dykes.’[1] 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.[1]

The island rises from the sea floor at approximately 50 m (160 ft) over a distance of approximately 0.75 km (0.47 mi) to 1 km (0.62 mi).[1][4]

Flora and fauna[edit]

Terrestrial Plants[edit]

As of 1996, a total of 26 plant species was reported as being present. The island’s upper platform is dominated by a shrubland of saltbush, dominated by Marsh Saltbush and Grey Saltbush while herbfields dominated by Austral Stork's Bill 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.[1]

Terrestrial animals[edit]

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 Shearwaters which are reported as using the island as a breeding colony.[1] As of 2013, the island is reported as being an unconfirmed breeding site for Flesh-footed Shearwaters.[5]

History[edit]

The island was first sighted by Europeans on Saturday 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 Sunday 21 February 1802 when one of the HMS Investigator’s cutters capsized near Cape Catastrophe. The island was surveyed by Thomas Lipson, 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.[6][7][8]

Navigation aids[edit]

A navigation aid consisting of a 6 m (20 ft) tower with a single flashing light was located on the west side of the island since 1963. An area of land of approximately 0.3 ha (0.74 acres) 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.[9][10][11]

Economic activity[edit]

Gauno[edit]

Williams Island is one of the island sites from which guano was mined under licence from the South Australian Government prior to 1919.[12]

Protected area status[edit]

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.[13] As of December 2012, the waters surrounding the island are in the Thorny Passage Marine Park.[14]

References[edit]

  1. ^ a b c d e f Robinson, A. C.; Canty, P., Mooney, T. and Rudduck, P. (1996). "South Australia's offshore islands". Australian Heritage Commission. pp. 222–223. Retrieved 13 December 2013. 
  2. ^ South Australia. Department of Marine and Harbors (1985), The Waters of South Australia a series of charts, sailing notes and coastal photographs, Dept. of Marine and Harbors, South Australia, pp. Chart 33, ISBN 978-0-7243-7603-2 
  3. ^ Robinson, A. C.; Canty, P., Mooney, T. and Rudduck, P. (1996). "South Australia's offshore islands". Australian Heritage Commission. p. 11. Retrieved 13 December 2013. 
  4. ^ Royal Australian Navy Hydrographic Service Hydrographic Department (1983). Port Lincoln and approaches (chart no. Aus 134). 
  5. ^ Goldsworthy, S.D.; Lavers, J., Carey, M. and Lowther, A.D. (2013). "Assessment of the status of the Flesh-footed Shearwater in South Australia: population status, subspecies status and foraging ecology. Final Report to Nature Foundation SA (SARDI Publication No. F2013/000013-1. SARDI Research Report Series No. 736)". South Australian Research and Development Institute (Aquatic Sciences). p. 3. Retrieved 6 April 2014. 
  6. ^ Flinders, Matthew (1966) [1814]. A Voyage to Terra Australis : undertaken for the purpose of completing the discovery of that vast country, and prosecuted in the years 1801, 1802, and 1803 in His Majesty's ship the Investigator, and subsequently in the armed vessel Porpoise and Cumberland Schooner; with an account of the shipwreck of the Porpoise, arrival of the Cumberland at Mauritius, and imprisonment of the commander during six years and a half in that island. (Facsimile ed.). Adelaide; Facsimile reprint of: London : G. and W. Nicol, 1814 ed. In two volumes, with an Atlas (3 volumes): Libraries Board of South Australia. p. 227. Retrieved 9 March 2013. 
  7. ^ "An historic tablet; The Flinders inscription discovered". Chronicle. 26 April 1924. p. 53. Retrieved 6 April 2014. 
  8. ^ Robinson, A. C.; Canty, P., Mooney, T. and Rudduck, P. (1996). "South Australia's offshore islands". Australian Heritage Commission. p. 126. Retrieved 13 December 2013. 
  9. ^ Robinson, A. C.; Canty, P., Mooney, T. and Rudduck, P. (1996). "South Australia's offshore islands". Australian Heritage Commission. p. 129. Retrieved 13 December 2013. 
  10. ^ "Listed by State (i.e. lighthouses & navigation aids)". Australian Lighthouses. Retrieved 2 April 2014. 
  11. ^ "Memory Cove Wilderness Protection Area Management Plan,". Department of Environment Water and Natural Resources. 2005. p. 17. Retrieved 26 January 2014. 
  12. ^ Robinson, A. C.; Canty, P., Mooney, T. and Rudduck, P. (1996). "South Australia's offshore islands". Australian Heritage Commission. p. 134. Retrieved 13 December 2013. 
  13. ^ "Memory Cove Wilderness Protection Area Management Plan,". Department of Environment Water and Natural Resources. 2005. p. 1. Retrieved 26 January 2014. 
  14. ^ "Thorny Passage Marine Park Management Plan 2012". Department of Environment Water and Natural Resources. 2012. pp. 27/31. Retrieved 3 April 2014.