Lewis Island (South Australia)

Lewis Island

Lewis Island
Geography
Location	Spencer Gulf
Coordinates	34°57′20″S 136°01′54″E / 34.95556°S 136.03167°ECoordinates: 34°57′20″S 136°01′54″E / 34.95556°S 136.03167°E
Administration
Australia

Lewis Island is an island located in Spencer Gulf off the east coast of Jussieu Peninsula on Eyre Peninsula in South Australia approximately 29 km (18 mi) south-east of Port Lincoln. It was named by Matthew Flinders in memory of George Lewis who was one of the eight crew lost from a cutter that capsized sometime after being 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

Lewis Island is located approximately 29 km (18 mi) south-east of Port Lincoln, 926 m (3,038 ft) south of Little Island and 2.8 km (1.7 mi) north of Smith Island. The island has a maximum height of 44 m (144 ft) above sea level. Access is possible by boat on the island’s north east coast during calm weather subject to tidal conditions, particularly in the channel separating it from Little Island.^[1][2]

Formation, geology and oceanography

Lewis Island was formed about 8400 years ago when sea levels rose at the start of the Holocene.^[3] The island’s structure consists of granite outcrop finished with a capping of calcarenite. Unlike the neighbouring islands, the island’s cap finishes in a peak at its southern end rather in lieu of a flat plateau.^[2] The island rises from the seabed at 30 m (98 ft) over a distance of within 100 m (330 ft) on its west, south and east faces.^[1]

Flora and fauna

Terrestrial plants

As of 1996, the island was dominated by a shrubland of marsh saltbush on its deeper soil. It also supported at least 19 other species including sea celery, karkalla, grey samphire, Australian hollyhock, native juniper, austral stork's bill and pointed twinleaf. Disturbance of the island’s surface by guano mining was suggested as the opportunity for weeds, particularly the African box thorn, to spread onto the island.^[2]

Terrestrial animals

As of 1996, a breeding colony of white-faced storm petrels was present on the higher southern section of the island. Also, the presence of "relatively high number" of silver gulls and Pacific gulls also suggested the possibility of the island being a breeding site for these species. Black-faced shags were also observed roosting at the island’s water line. Reptiles are represented by marbled geckos, four-toed earless skinks and bull skink.^[2] As of 2013, the island is reported as being a breeding site for flesh-footed shearwaters.^[4]

Marine animals

As of 1996, observations of burrows immediately below the island’s calcarenite capping suggests that it may have supported a colony of little penguins.^[2] As of 2007, a breeding population of Australian sea lions is reported to be present on the island.^[5]

History

The island was one of several first sighted by Europeans on Saturday, 20 February 1802, from HMS Investigator whilst under the command of Matthew Flinders entered what is now Spencer Gulf.^[6]

Flinders named the island on Wednesday, 24 February 1802, in memory of George Lewis who 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.^[7][8]

Economic activity

Gauno

Lewis Island is one of the island sites from which guano was mined under licence from the South Australian Government prior to 1919.^[9]

Protected areas status

Since 30 September 2004, Lewis Island has been part of the Memory Cove Wilderness Protection Area. Previously, it had been part of the Lincoln National Park.^[10] It originally obtained protected area status as a fauna reserve under the former Fauna Conservation Act 1964 in 1965.^[11] As of December 2012, the waters surrounding the island are in the Thorny Passage Marine Park.^[12]

References

1. Royal Australian Navy Hydrographic Service (1983). Port Lincoln and approaches (chart no. Aus 134).
2. Robinson, A. C.; Canty, P.; Mooney, T.; Rudduck, P. (1996). "South Australia's offshore islands" (PDF). Australian Heritage Commission. pp. 240–241. Retrieved 13 December 2013.
3. Robinson, A. C.; Canty, P.; Mooney, T.; Rudduck, P. (1996). "South Australia's offshore islands" (PDF). Australian Heritage Commission. p. 11. Retrieved 13 December 2013.
4. Goldsworthy, S.D.; Lavers, J.; Carey, M.; 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)" (PDF). South Australian Research and Development Institute (Aquatic Sciences). p. 3. Retrieved 6 April 2014.
5. Goldsworthy, S.D.; Shaughnessy, P.D.; Page, B.; Dennis, T.E.; McIntosh, R.R.; Hamer, D.; Peters, K.J.; Baylis, A.M.M.; Lowther, A.; Bradshaw, CJA (2007). Developing population monitoring protocols for Australian sea lions (PDF). South Australian Research and Development Institute. p. 46. ISBN 9780730853701.
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. 228. Retrieved 9 March 2013.
7. 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. 232. Retrieved 9 March 2013.
8. "An historic tablet; The Flinders inscription discovered". Chronicle. 26 April 1924. p. 53. Retrieved 6 April 2014.
9. Robinson, A. C.; Canty, P.; Mooney, T.; Rudduck, P. (1996). "South Australia's offshore islands" (PDF). Australian Heritage Commission. p. 134. Retrieved 13 December 2013.
10. "Memory Cove Wilderness Protection Area Management Plan," (PDF). Department of Environment Water and Natural Resources. 2005. p. 1. Retrieved 26 January 2014.
11. Robinson, A. C.; Canty, P.; Mooney, T.; Rudduck, P. (1996). "South Australia's offshore islands" (PDF). Australian Heritage Commission. p. 140. Retrieved 13 December 2013.
12. "Thorny Passage Marine Park Management Plan 2012" (PDF). Department of Environment Water and Natural Resources. 2012. pp. 27/31. Retrieved 3 April 2014.