Pedra Branca (Tasmania)

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Pedra Branca and Eddistone (1823)

Pedra Branca is a 2.5 ha rock or small island about 26 km (16 mi) south-south-east of South East Cape, Tasmania, in south-eastern Australia. It is known for its inaccessibility, rich marine wildlife, wet and windy weather, interesting geology and large waves. It is part of the Southwest National Park, and thus in the Tasmanian Wilderness World Heritage Site.

The name means "White Rock" in Portuguese. According to historian Kenneth McIntyre, Pedra Branca is one of only two Australian places with a name of Portuguese origin, the other being the Houtman Abrolhos islands in Western Australia.

History

Abel Tasman led the first known European expedition to sight Tasmania. His journal entry for 29 November 1642[1] records that he observed a rock which was similar to a rock named Pedra Branca off China, presumably referring to the Pedra Branca in the South China Sea. The journal places Pedra Branca about 4 miles (6.4 km) from the mainland of Tasmania, however a Dutch mile from this period was about 5.8 km, thus 4 such Dutch miles would be 23 km, which is close to the actual distance of Pedra Branca from South East Cape.

Shipwreck

On 7 February 1973 Nisshin Maru No.8, a Japanese steel fishing vessel of 254 gross tons led by Captain Nakayama, on its way to Hobart for a mechanical inspection, hit Pedra Branca and sank in deep water within a few minutes. In the ensuing confusion only one of the crew of 22, engineer Yoshiichi Meguro, managed to clamber onto the rocks and escape drowning. The fishing vessel Walrus rescued the survivor.

The Nisshin Maru No.8 disaster led to considerable improvements in communications between the various authorities that should have been able to mount a rescue operation many hours before this one was commenced. These included direct links between Japanese fishing boats and Australian shore stations, and correcting the inability of fishing vessels to directly contact warships and military aircraft, as they were unable to contact the Hobart emergency radio station which did not operate at night.

Geography

Pedra Branca is an erosional remnant of the Tasmanian mainland. It is approximately 270 metres (885 ft) long, 100 metres (330 ft) wide, and 60 metres (200 ft) high. This is small enough to provide an example of an outcrop that lies on the border between being a rock or islet and an island. The island is estimated to have separated from the mainland at least 15,000 years ago.[2]

The geology features three breccia cones of dolerite and sandstone.[3]

Weather

Weather conditions in the area can be extreme, and Pedra Branca is occasionally swept by freak waves. On 15 April 2003 oceanographer Hamish Saunders drowned after being washed off Pedra Branca. The Coroner's Report [4] into his death includes reports from three witnesses who describe how Saunders was swept away when a "wave hit the island resulting in heavy spray coming up to and over the 45 metre (148 ft) level". Waves were measured that day at up to 13.8 metres (45.3 ft) by the Cape Sorell Waverider Buoy, some 100 kilometres (62 mi) away.

Flora and fauna

The only plant species found on the island is the succulent Sarcocornia quinqueflora. Recorded breeding seabird species include Fairy Prion, Pacific Gull, Silver Gull, Kelp Gull, Black-faced Cormorant, Australasian Gannet, and Shy Albatross.[3] Australian Fur Seals use the island as a regular haul-out site while New Zealand Fur Seals visit occasionally.[5]

Remarkably, the tiny, windswept island is the only known habitat of a species of lizard, the Pedra Branca Skink, Niveoscincus palfreymani, which has survived for an estimated 15,000 years since Pedra Branca was separated from the Tasmanian mainland.[2] An estimated 400 individuals survive, but the species is listed as Vulnerable.[3]

Important Bird Area

Together with the nearby Eddystone and Sidmouth Rock the island constitutes the 2 ha Pedra Branca Important Bird Area (IBA), identified as such by BirdLife International because it supports over 1% of the world populations of Shy Albatrosses and Australasian Gannets.[6]

See also

References

  1. Heeres, J E (Editor) (2006). "Abel Janszoon Tasman's Journal of his Discovery of Van Diemen's Land and New Zealand in 1642 with Documents Relating to his Exploration of Australia in 1644...to which are added his Life and Labours, 1898". Project Gutenberg of Australia. Retrieved 2006-07-09. 
  2. 2.0 2.1 "Pedra Branca Skink". Parks & Wildlife Service Tasmania. pp. 563–569. Retrieved 2006-07-16. 
  3. 3.0 3.1 3.2 "Small Southern Islands Conservation Management Statement 2002" (PDF). Tasmania Parks and Wildlife Service. 2002. Archived from the original on 2006-08-22. Retrieved 2006-07-16. 
  4. Coroner (2004-11-05). "Coronial Findings, drowning 15th April 2003 of Hamish Alan Saunders". Magistrates Court of Tasmania. Archived from the original on 2006-04-27. Retrieved 2006-06-05. 
  5. Brothers, Nigel; Pemberton, David; Pryor, Helen; & Halley, Vanessa. (2001). Tasmania’s Offshore Islands: seabirds and other natural features. Tasmanian Museum and Art Gallery: Hobart. ISBN 0-7246-4816-X
  6. "IBA: Pedra Branca". Birdata. Birds Australia. Retrieved 2011-09-16. 

Coordinates: 43°51′36″S 146°58′28″E / 43.86000°S 146.97444°E / -43.86000; 146.97444

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