Ducie Island

From Wikishire
Jump to: navigation, search
Ducie

Pitcairn Islands

DucieISS002-E-10044 - Cropped.JPG
Satellite photograph of Ducie Island
Location
Location: 24°40’9"S, 124°47’11"W
Area: 0.27 square miles
Highest point: 15 feet
Data

Ducie Island is an uninhabited atoll in the Pitcairn Islands. It lies 290 miles east of Pitcairn and has a total area of 1.5 square miles, which includes the lagoon. It is a mile and half long, measured northeast to southwest, and about a mile wide. The island is composed of four islets: Acadia, Pandora, Westward and Edwards.

Despite its sparse vegetation, the atoll is known as the breeding ground of a number of bird species. More than 90% of the world population of Murphy's Petrel nests on Ducie, while pairs of Red-tailed Tropicbirds and Fairy Terns make around 1% of the world population for each species.

Ducie was first discovered in 1606 by Pedro Fernandes de Queirós, who named it Luna Puesta, and rediscovered by Edward Edwards, captain of HMS Pandora, who was sent in 1790 to capture the mutineers of HMS Bounty. He named the island Ducie in honour of Francis Reynolds-Moreton, 3rd Baron Ducie. In 1867 it was claimed by the United States under the Guano Islands Act, but the United Kingdom annexed it on 19 December 1902 as part of the Pitcairn Islands. Due to its inaccessibility and the distance from Pitcairn Island, Ducie is rarely visited today.

Geography

Ducie lies 290 miles east of Pitcairn Island. It is an atoll, a coral ring with a central lagoon, and is claimed to be the southernmost atoll in the world at 24° South[1] (a claim disputed by proponants of Australia’s Middleton Reef at 29° South, if the latter can be called an atoll). Ducie Island's land area is 170 acres and its maximum elevation, occurring on the Westward islet, is 15 feet.[2]

Islets of Ducie

The atoll consists of four islets:

  • Acadia Islet along the atoll's north and east rim, which is larger than the other three islets combined, measuring 140 acres.[1] Very long and thin, the islet is largely forested and is composed of ridges of coral rubble. It is named after the Acadia, a ship that was wrecked on Ducie in 1881.[3]
  • Pandora Islet in the south, the second largest. It is composed of sand and coral rubble that borders the lagoon. It is named after HMS Pandora.[4]
  • Edwards Islet lies immediately to the east of Pandora Islet and has the same characteristics. It is named after Edward Edwards, captain of HMS Pandora.[4]
  • Westward Islet, west of Pandora Islet, the smallest. It appears sandy from a distance, but the soil is composed of coral rubble and dead shells. Its highest point rises 15 feet above average sea level. It is named after the Westward, the ship that carried the members of the National Geographic Society and the Oceanic Institute during their 1970–71 expedition.[2]

Pandora, Westward and Edwards can be all accessed on foot from Acadia at low tide.[1] The islets were named by Harald Rehder and John Randall, who visited the atoll during an expedition by the Smithsonian Institution in 1975.[5]

The atoll has a central lagoon, accessible by boat only by way of a channel 100 yards wide in the southwest, between Pandora and Westward Islets.[6] It has a maximum depth of 52.0 feet (15.8 m) and its bottom consists of sand and coral.[7] Whirlpools in the lagoon are common, caused by tunnels that drain the water from the lagoon into the ocean.[8]

Ducie is to be found 620 miles west of the edge of the Easter Plate. It was formed approximately 8 million years ago,[9] after Oeno Island was formed by a hotspot that later caused a magma leak generated in the Oeno lineation. The leak spread over fracture zone FZ2, which was formed by the third movement of the Pacific Plate.[10] The atoll is part of the Oeno-Henderson-Ducie-Crough seamount, speculated to be part of the southern Tuamotus.[11]

History

Ducie was discovered by a Spanish expedition led by Portuguese sailor Pedro Fernandes de Queirós on 26 January 1606, during an expedition that began in Callao, Peru[12] whose objective was to take soldiers, friars and provisions to establish a colony in the Santa Cruz Islands.[13] Ducie was the first of eighteen discoveries on the trip. Queirós named the island Luna Puesta (roughly, "moon that has set"). On the same day, he also sighted two more islands, one that he named San Juan Bautista ("St John the Baptist"), and the other La Encarnación ("the Incarnation"). It is unclear which one was Henderson island and which one Pitcairn.[14] The confusion was later compounded when a chart produced by Admiral José de Espinosa marked Ducie as La Encarnación, rather than as Luna Puesta.[15]

The island was rediscovered, properly charted and named 'Ducie Island' on 16 March 1791 by Captain Edward Edwards, of HMS Pandora, who had been despatched from Britain in 1790 to arrest the Bounty mutineers.[15] Edwards named it in honour of Francis Reynolds-Moreton, 3rd Baron Ducie, under whom he had served earlier in his career.[16] HMS Pandora turned northwards from Ducie and, because of this change of course, Edwards did not sight the other islands of the group. If HMS Pandora had maintained its course, it would eventually have reached Pitcairn Island and found the Bounty mutineers.[17]

Some of the survivors of the wreck of the whaleship Essex, which had been attacked and sunk by a whale in November 1820, mistakenly believed that they had reached Ducie after a month at sea in two whaleboats. In fact they had reached Henderson Island.[18] The first recorded landing on Ducie was made in the same year by Captain Thomas Raine of the Surrey, who was searching for the survivors of the Essex.[14] The first comprehensive description of the island was written by Frederick William Beechey, who arrived in HMS Blossom during November 1825. Beechey's expedition did not land in the atoll, but members of the crew navigated around it in small boats.[19] Based on Beechey's survey, the first Admiralty chart of the island was published in 1826. For nearly a hundred years it was the only available map of the island.[20]

Map of Ducie (1826) based on the Beechey's descriptions

On 5 June 1881 the mail ship Acadia ran aground on the island while returning from San Francisco, Peru after unloading its cargo. On the way to Queenstown or Falmouth in Tasmania for new orders, Master Stephen George calculated a route passing 15 to 20 miles to the east of Ducie. George left the first mate in command at 6 am. Half an hour later, the first mate saw a white line, which he disregarded on the assumption that it was phosphorescence in the water. Later, realising that it was land, he manoeuvred to avoid running aground, but failed. The look-out excused himself by saying that he thought that the white land was a cloud. The crew made several unsuccessful attempts to re-float the ship, after which the master sailed one of the ship's boats to Pitcairn Island. He was assisted there by the local inhabitants and returned aboard the Edward O'Brien, an American boat, to rescue the rest of the crew. The incident was later investigated in a court in Liverpool, where the ultimate cause of the wreck was left undetermined, though possible causes included a calculation error by the master or an unknown current that carried the ship to the island. The court declared the master not guilty of any wrongdoing.[21] A stone marker with a memorial inscription is located at the landing point on Acadia Islet. It was unveiled to commemorate the recovery of the anchor in 1990. The wreck lies offshore from the memorial stone in about 5 fathoms of water.[22]

In 1969 the atoll was proposed as an "Island for Science",[23] and was later recommended as a Ramsar Site.[24] Major expeditions that came to the island to record its biota include the Whitney South Seas Expedition in 1922, the National Geographic Society-Oceanic Institute Expedition to Southeast Oceania of 1970–71[23] and the Smithsonian expedition of 1975.[25] More recent expeditions include a new expedition by the Smithsonian in 1987,[26] one by Raleigh International in the same year,[23] the Sir Peter Scott Commemorative Expedition of 1990–91[26] and the Pitcairn Scientific Expedition of 1991–92.[25] In 2012, National Geographic Explorer-in-Residence Enric Sala produced Sharks Of Lost Island including Ducie and all the Pitcairn Islands.[27] Because of its inaccessibility, Ducie is rarely approached,[8] but cruise ships make one or two landings a year.[28] In addition, unrecorded visits are known to be made by freighters and tankers that dump residues on the island or in the nearby waters.[8]

Sovereignty

Although Captain Edward Edwards discovered the atoll in 1791, Ducie was not considered a British possession.[29] In 1867 Ducie was claimed by the United States under the Guano Islands Act, which established that an uninhabited territory with guano deposits could be claimed as a US possession, so long as it was unclaimed by any other country.[30] Ultimately, the United States did not assert its sovereignty over this nor most of the paper claims of the Guano Act.

Under the 1893 Pacific Order in Council, the British Western Pacific Territories were separated from the colony of Fiji. On 19 December 1902, commissioned by R T Simmons, the British Consul in Tahiti, Captain G F Jones and a group of Pitcairners visited the nearby islands and annexed them to the United Kingdom.[31] In 1903 Ducie was annexed by the same procedure.[32][33] R T Simmons stated in a dispatch to the Foreign Office that James Russell McCoy had assured him that the islands had always been considered as dependencies of Pitcairn, and that he and other Pitcairners had frequently visited them in the past.

On 4 August 1937 Captain J W Rivers-Carnac, commander of HMS Leander, reaffirmed British sovereignty over Ducie by hoisting the Union Flag and placing boards proclaiming the island to be the property of King George VI.[14] Ducie was one of several islands thought valuable for potential seaplane bases, though they did not materialise.[34] In 1953, the Pitcairn Islands became British colony separate from Fiji.[35]

Flora

The vegetation in the atoll is sparse, because of the lack of fresh water.[8] Only two species of vascular plant are currently known to grow there[36] – one of the smallest such floras on any island.[26] Acadia, Pandora and Edwards Islets are forested with Heliotropium foertherianum,[37] but Westward Islet is not. Pemphis acidula has also been recorded on Ducie; specimens were found during an expedition in 1991.[1] During the expedition of Hugh Cuming in 1827 and the 1922 Whitney South Sea Expedition, Lepturus grass was found on Acadia Islet.[38] However, it disappeared when storm waves deforested the island some time before the Smithsonian expedition of 1975.[39] Thus H. foertherianum now dominates the vegetation of the islets.[40] Additionally, there are a number of species of coralline algae, including Porolithon onkodes, Porolithon gardineri, and Caulerpa racemosa.[7] The flora of the lagoon consists mainly of dead coral, presumed to have been killed by influxes of cold water. Sparse living coral still can be found;[1] the dominant species is Montipora bilaminata (family Acroporidae).[7]

Fauna

The atoll is populated by several species of birds, fish and reptiles.

Birds

Though no terrestrial birds are found on the atoll,[28] Ducie Island is well known for the seabirds that breed there.[22] Birds that have been recorded nesting on the atoll include the Red-billed Tropicbird, Red-tailed Tropicbird, Fairy Tern, Great Frigatebird, Bristle-thighed Curlew, Masked Booby and Red-footed Booby. A number of gull species, including the Sooty Tern, Blue Noddy, Brown Noddy, Lesser Noddy and White Tern, have been recorded, as have several members of the Procellariidae family: Kermadec Petrel, Trindade Petrel, Murphy's Petrel and Christmas Shearwater.[41] The island is particularly important for Murphy's Petrel, as more than 90% of its world population breeds on Ducie.[42] Around 3000 pairs of Christmas Shearwaters, about 5% of the world's total population, can be found on the island too. Meanwhile, the Red-tailed Tropicbirds and Fairy Terns that breed on Ducie are around 1% of the world population of each species.[1] Phoenix Petrels, which previously inhabited the atoll, apparently disappeared between the Whitney expedition in 1922 and the 1991–92 Pitcairn Scientific Expedition.[28] The island has been identified by BirdLife International as an 'Important Bird Area', principally for its colonies of Murphy's, Herald and Kermadec Petrels, and Christmas Shearwaters.[43]

Fish

In the lagoon there are around 138 fish species, which also inhabit the southeastern Pacific, the Western Pacific and the Indian Ocean.[44] The lagoon is noted for its poisonous fishes and dangerous sharks.[45] The yellow-edged lyretail, the blacktip grouper, and the greasy grouper are known to cause ciguatera poisoning.[44] The lagoon is also inhabited by Galapagos sharks and the whitetip reef shark.[46] The Galapagos shark is dangerous to humans,[47] while the whitetips are seldom aggressive unless provoked.[48] Five species are found exclusively around the Pitcairn Islands: Sargocentron megalops (a species of squirrelfish), the spiny butterflyfish, the Henderson triplefin (a species of threefin blenny), an unnamed species of Alticus (a genus of combtooth blenny) and an unnamed species of Ammodytes (a genus of sand lance).[49]

Terrestrial vertebrates

Lizards that inhabit the island include the white-bellied skink (Emoia cyanura), photographed by E. H. Quayle during an expedition in 1922, and a lizard reported in the journal of an expedition in 1935 by James Chapin. The species of the latter was uncertain, but it was thought to be a gecko, possibly either an oceanic gecko (Gehyra oceanica) or a mourning gecko (Lepidodactylus lugubris).[50] The 1991–92 Pitcairn Scientific Expedition found specimens of both the mourning gecko and the white-bellied skink.[25] The only mammal known to inhabit Ducie is the Polynesian rat;[38] there has been a successful programme to eradicate these, to aid the conservation of bird species threatened by the increasing rat population.[51] Green sea turtles feed on Ducie, but have not been seen to breed there.[1]

Outside links

Commons-logo.svg
("Wikimedia Commons" has material
about Ducie Island)

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Ramsar Information Sheet: UK62001; p.2
  2. 2.0 2.1 Rehder, Harald A.; Randall, John E.; p.11
  3. Rehder, Harald A.; Randall, John E.; p.12
  4. 4.0 4.1 Rehder, Harald A.; Randall, John E.; p.13
  5. Rehder, Harald A.; Randall, John E.; p.9
  6. Rehder, Harald A.; Randall, John E.; p.15
  7. 7.0 7.1 7.2 Rehder, Harald A.; Randall, John E.; p.14
  8. 8.0 8.1 8.2 8.3 Stanley, David (7th edition); p.286
  9. Spencer; p.5
  10. Spencer; p.1
  11. Vacher, Leonard; Quinn, Terrence (1997). Geology and Hydrogeology of Carbonate Islands - Elsevier. ISBN 978-0-444-81520-0
  12. Brand, Donald D The Pacific Basin: A History of its Geographical Explorations The American Geographical Society (New York, 1967) p.136.
  13. Paine, Lincoln; p.122
  14. 14.0 14.1 14.2 "History of Government and Laws, Part 15". Pitcairn Islands Study Center. Pacific Union College. http://library.puc.edu/pitcairn/pitcairn/govt-history15.shtml. Retrieved 10 July 2011. 
  15. 15.0 15.1 Edwards, Edward; p.60
  16. Heffernan, Thomas; p.80
  17. Edwards, Edward; p.5
  18. Whipple, A.B.C p. 150
  19. Beechey; p.60
  20. Rehder, Harald A.; Randall, John E.; p.6
  21. Board of Trade p.1
  22. 22.0 22.1 McKinnon, Rowan; p.249
  23. 23.0 23.1 23.2 "The Wetlands: Ducie Atoll". Wetlands International. Pacific Union College. http://library.puc.edu/pitcairn/pitcairn/wetlands_ducie.shtml. Retrieved 17 July 2011. 
  24. Ramsar; p. 3
  25. 25.0 25.1 25.2 The Royal Society of New Zealand, p.161
  26. 26.0 26.1 26.2 D. G. Frodin; p.917
  27. "Sharks of Lost Island". National Geographic. http://channel.nationalgeographic.com/wild/episodes/sharks-of-lost-island/. 
  28. 28.0 28.1 28.2 Ramsar Information Sheet: UK62001; p.4
  29. Orent, Beatrice; Reinsch, Pauline; p.444
  30. United States Department of Justice; p.555
  31. Rehder, Harald A.; Randall, John E.; p.7
  32. Orent, Beatrice; Reinsch, Pauline; p.445
  33. Ntumy, Michael A.; p.253
  34. Orent, Beatrice; Reinsch, Pauline; p.447
  35. Ntumy, Michael A.; p.254
  36. Procter, D.; Fleming, L.V.; p. 90
  37. Quayle, Ernest H.; p.392
  38. 38.0 38.1 Rehder, Harald A.; Randall, John E.; p.18
  39. Rehder, Harald A.; Randall, John E.; p.8
  40. Fosberg et al. p.18
  41. Rehder, Harald A.; Randall, John E.; pp.18 20
  42. IUCN (2010); "Pterodroma ultima".
  43. BirdLife International. (2012). Important Bird Areas factsheet: Ducie Island. Downloaded from http://www.birdlife.org on 2012-01-21.
  44. 44.0 44.1 Rehder, Harald A.; Randall, John E.; p.26
  45. "Ducie Island". Pitcairn Islands Study Center. Pacific Union College. http://library.puc.edu/Pitcairn/pitcairn/ducie.shtml. Retrieved 3 July 2011. 
  46. Rehder, Harald A.; Randall, John E.; p.17
  47. Edwards, A.J. and Lubbock, H.R. (23 February 1982). "The Shark Population of Saint Paul's Rocks". Copeia (American Society of Ichthyologists and Herpetologists) 1982 (1): 223–225. doi:10.2307/1444304. 
  48. Compagno, L.J.V. (1984). Sharks of the World: An Annotated and Illustrated Catalogue of Shark Species Known to Date. Rome: Food and Agricultural Organization. pp. 535–538. ISBN 92-5-101384-5. 
  49. UK62001; p.3
  50. Rehder, Harald A.; Randall, John E.; p.20
  51. MacLean; p.198

Bibliography of sources

The Pitcairn Islands

DucieHendersonOenoPitcairn