Bald Island

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Bald Island is located in Western Australia
Bald Island
Bald Island
Location of Bald Island

Bald Island is an island that is located in the Great Southern region of Western Australia. The island is 1.5 kilometres (1 mi) offshore from Cheynes Beach and is a protected area managed by the Department of Parks and Wildlife.

The island is a World Conservation Union Category IA nature reserve. (A Class A Nature Reserve, No 25869, managed by Parks and Wildlife was created in 1964.)[1] With an area of 8.09 square kilometres (1,999 acres)[2] the island is one of the largest off the South Coast. Composed almost entirely of granite the island rises steeply from the ocean to a maximum height of 310 metres (1,017 ft). The island was isolated around 10,000 years ago by rising sea levels.[3]

Flora[edit]

The Island contains 104 species of plant.[4] Large stands of peppermint trees (Agonis flexuosa) are found on the sheltered upper slopes of the island, while forested stretches of rottnest teatree (Melaleuca lanceolata) are also found on the lower slopes. The Bald Island marlock (Eucalyptus conferruminata) forms dense thickets on parts of the island. More exposed areas are covered by open heath and tussock species and closed shrub mostly comprising Melaleuca microphylla.

Fauna[edit]

The island supports a good population of reptiles - four skinks and one gecko. One of the species of skink, Ctenotus labillardieri, has evolved into a distinctive insular race on the island. There are no snakes on the island. Marine mammals such as New Zealand fur seals and Australian sea lions inhabit Bald Island. There are a few mainland mammals including the quokka, and a population of Gilbert's potoroo is also being established. The island forms part of the Two Peoples Bay and Mount Manypeaks Important Bird Area, identified as such by BirdLife International because of its significance in the conservation of several rare and threatened bird species.[5] It acts as an important breeding ground for great-winged petrels and little penguins.

Translocations[edit]

Due to its location and lack of easy landing places on the shores of the island, it is in almost pristine condition. The island was chosen in August 2005 as a site for the translocation of a Gilbert's potoroo population[6] from the Two Peoples Bay Nature Reserve. More of the rare species were sent in 2007 to bring the total population to seven.[7] The island was chosen due to its lack of predators such as cats, foxes and snakes.

Another endangered species translocated to Bald Island is the noisy scrub-bird. In 1992 five males were taken from the Two Peoples Bay area and taken to Bald Island. In 1993 the area was surveyed to show that at least two had survived. In 1993 another three males and three females have been relocated to Bald Island.[8] The estimated population of calling male birds on Bald Island in 2004 is 59 individuals.[9]

References[edit]

  1. ^ "Department of Environment - Terrestrial Protected Areas - Western Australia". 1998. Archived from the original on 28 March 2011. Retrieved 2010-10-15. 
  2. ^ "Naturebase - Gilbert's Potoroo Research Activities". 2007. Retrieved 7 October 2007. 
  3. ^ E. A. Sinclair (1998). "Morphological variation among populations of the quokka, Setonix brachyurus (Macropodidae : Marsupialia), in Western Australia" (PDF). Australian Journal of Zoology. CSIRO Publishing. 46: 439–449. doi:10.1071/ZO98014. Retrieved 29 January 2012. [permanent dead link]
  4. ^ "Aussie Heritage - Cape Vancouver to Bald Island Marine Area". 2007. Archived from the original on 13 September 2007. Retrieved 7 October 2007. 
  5. ^ BirdLife International. (2011). Important Bird Areas factsheet: Two Peoples Bay and Mount Manypeaks. Downloaded from "Archived copy". Archived from the original on 10 July 2007. Retrieved 2013-09-01.  on 18 November 2011.
  6. ^ "Endangered Potoroos doing fine in their new home". Australian Broadcasting Corporation. 2005. Retrieved 7 October 2007. 
  7. ^ "Bald Island home to two more Gilbert's potoroos". 2007. Archived from the original on 3 September 2007. Retrieved 7 October 2007. 
  8. ^ "Department of Environment - Noisy Scrub-bird (Atrichornis clamosus) Recovery Plan". 1994. Archived from the original on 21 September 2007. Retrieved 7 October 2007. 
  9. ^ "Birdlife International - Noisy Scrub-bird - BirdLife Species Factsheet". 2004. Retrieved 7 October 2007. 

Coordinates: 34°55′9.07″S 118°27′45.48″E / 34.9191861°S 118.4626333°E / -34.9191861; 118.4626333