Gough Island

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Gough
Gough island top view.png
View of Gough Island.
Gough Island is located in South Atlantic
Gough Island
Gough Island
Location of Gough Island in the South Atlantic Ocean
Geography
Location South Atlantic Ocean
Coordinates 40°19′S 9°56′W / 40.32°S 9.94°W / -40.32; -9.94Coordinates: 40°19′S 9°56′W / 40.32°S 9.94°W / -40.32; -9.94
Archipelago  Tristan da Cunha
Area 91 km2 (35 sq mi)
Length 13 km (8.1 mi)
Width 7 km (4.3 mi)
Highest elevation 910 m (2,990 ft)
Highest point Edinburgh Peak
Country
St Helena, Ascension and Tristan da Cunha

Gough Island /ˈɡɒf/, also known historically as Gonçalo Álvares (after the Portuguese explorer) or mistakenly as Diego Alvarez, is a volcanic island in the South Atlantic Ocean. It is a dependency of Tristan da Cunha and part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha. It is uninhabited except for the personnel of a weather station (usually six people) which the South African National Antarctic Programme has maintained continually on the island since 1956. It is one of the most remote places with a constant human presence.

Gough Island and Inaccessible Island comprise the UNESCO World Heritage Site of Gough and Inaccessible Islands.

Name[edit]

The island was first named Ilha de Gonçalo Álvares on Portuguese maps (Spanish Isla de Gonzalo Álvarez). It was named Gough Island after Captain Charles Gough of the Richmond who sighted the island in 1732. Confusion of the unusual Portuguese saint name Gonçalo with Spanish Diego led to the misnomer "Diego Alvarez island" in English sources from the 1800s to 1930s.[1][2][3]

History[edit]

The details of the discovery of Gough Island are unclear, but the most likely occasion is July 1505 by the Portuguese explorer Gonçalo Álvares.[4] Maps during the next three centuries named the island after him. On some later maps, this was erroneously given as Diego Alvarez. According to some historians, the English merchant Anthony de la Roché was the first to land on the island, in Spring 1675.[5]

Charles Gough rediscovered the island on 3 March 1732, thinking it was Gonçalo Alvares.[6]

It was named Gonçalo Alvarez, after the captain of Vasco da Gama's flagship on his epic voyage to the east, and under this name it was marked with reasonable accuracy on the charts of the South Atlantic during the following 250 years. Then, in 1731, Captain Gough of the British ship Richmond reported the discovery of a new island, which he placed 400 miles to the east of Goncalo Alvarez. Fifty years later cartographers realised that the two islands were the same and despite the priority of the Portuguese discovery, and the greater accuracy of the position given by them, "Gough's Island" was the name adopted.[7]

In the early 19th Century, sealers sometimes briefly inhabited the island. The earliest known example is a sealing gang from the US ship Amethyst which remained on the island in 1806–1807.

Gough Island was claimed only in 1938, for Britain, during a visit by HMS Milford of the Royal Navy.[8]

In 1995 Gough Island was inscribed as a UNESCO World Heritage Site of Gough Island. In 2004 the site was extended to include Inaccessible Island and renamed Gough and Inaccessible Islands.

Geography and geology[edit]

Gough Island is roughly rectangular with a length of 13 km (8.1 mi) and a width of 7 kilometres (4.3 mi). It has an area of 91 km2 (35 sq mi) and rises to heights of over 900 m (3,000 ft) above sea level.[9] Topographic features include the highest Peak, Edinburgh Peak, Hags Tooth, Mount Rowett, Sea Elephant Bay, Quest Bay, and Hawkins Bay.

It includes small satellite islands and rocks such as Southwest Island, Saddle Island (South), Tristiana Rock, Isolda Rock (West), Round Island, Cone Island, Lot's Wife, Church Rock (North), Penguin Island (Northeast), and The Admirals (East). It is a remote, rugged and lonely place, about 400 km (250 mi) south-east of the other islands in the Tristan da Cunha group, 2,700 km (1,700 mi) from Cape Town, and over 3,200 km (2,000 mi) from the nearest point of South America.

Climate[edit]

The islands have a cool-temperate oceanic climate, and lie on the edge of the roaring forties.

Climate data for Gough Island
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °C (°F) 26.4
(79.5)
25.7
(78.3)
25.9
(78.6)
22.6
(72.7)
20.5
(68.9)
19.0
(66.2)
19.3
(66.7)
18.6
(65.5)
19.3
(66.7)
21.4
(70.5)
23.9
(75)
25.1
(77.2)
26.4
(79.5)
Average high °C (°F) 17.2
(63)
17.4
(63.3)
16.9
(62.4)
15.4
(59.7)
13.7
(56.7)
12.4
(54.3)
11.5
(52.7)
11.2
(52.2)
11.5
(52.7)
12.9
(55.2)
14.9
(58.8)
16.2
(61.2)
14.3
(57.7)
Daily mean °C (°F) 13.9
(57)
14.4
(57.9)
13.9
(57)
12.8
(55)
11.3
(52.3)
10.0
(50)
9.1
(48.4)
8.9
(48)
8.9
(48)
10.1
(50.2)
11.9
(53.4)
13.2
(55.8)
11.5
(52.7)
Average low °C (°F) 11.1
(52)
11.6
(52.9)
11.3
(52.3)
10.4
(50.7)
8.9
(48)
7.6
(45.7)
6.6
(43.9)
6.5
(43.7)
6.6
(43.9)
7.8
(46)
9.4
(48.9)
10.3
(50.5)
9.0
(48.2)
Record low °C (°F) 5.3
(41.5)
5.1
(41.2)
4.8
(40.6)
3.7
(38.7)
1.4
(34.5)
0.1
(32.2)
−0.9
(30.4)
−2.7
(27.1)
0.2
(32.4)
0.5
(32.9)
2.4
(36.3)
4.1
(39.4)
−2.7
(27.1)
Precipitation mm (inches) 210
(8.27)
183
(7.2)
254
(10)
276
(10.87)
286
(11.26)
310
(12.2)
273
(10.75)
304
(11.97)
270
(10.63)
249
(9.8)
213
(8.39)
241
(9.49)
3,069
(120.83)
Avg. precipitation days (≥ 1.0 mm) 16 13 18 19 21 22 23 21 20 18 16 18 225
 % humidity 81 82 82 82 82 83 83 83 81 81 81 81 82
Mean monthly sunshine hours 183.8 148.8 123.3 95.6 83.7 60.4 71.7 87.5 101.6 128.5 161.4 182.9 1,429.2
Source #1: NOAA[10]
Source #2: climate-charts.com[11]

Fauna and flora[edit]

the fern Blechnum and tree Phylica on Gough Island

Gough and Inaccessible Island are a protected wildlife reserve, which has been designated a World Heritage Site by UNESCO. It has been described as one of the least disrupted ecosystems of its kind and one of the best shelters for nesting seabirds in the Atlantic. In particular, it is host to almost the entire world population of the Tristan Albatross (Diomedea dabbenena) and the Atlantic Petrel (Pterodroma incerta).[12] The island is also home to the almost flightless Gough Island Moorhen,[13] and the critically endangered Gough Bunting.

Birds[edit]

The island has been identified as an Important Bird Area (IBA) by BirdLife International for its endemic landbirds and as a breeding site for seabirds. Birds for which the IBA has conservation significance include Northern Rockhopper Penguins (144,000 breeding pairs), Tristan Albatrosses (1000–1500 pairs), Sooty Albatrosses (5000 pairs), Atlantic Yellow-nosed Albatrosses (5000 pairs), Broad-billed Prions (100,000 pairs), Kerguelen Petrels (20,000 pairs), Soft-plumaged Petrels (50,000 pairs), Atlantic Petrels (20,000 pairs), Great-winged Petrels (5000 pairs), Grey Petrels (10,000 pairs), Great Shearwaters (100,000 pairs), Little Shearwaters (10,000 pairs), Grey-backed Storm Petrels (10,000 pairs), White-faced Storm Petrels (10,000 pairs), White-bellied Storm Petrels (10,000 pairs), Antarctic Terns (500 pairs), Southern Skuas (500 pairs), Gough Moorhens (2500 pairs) and Gough Buntings (3000 individuals).[14]

Mammals[edit]

The island has a large breeding population of subantarctic fur seals.

House mice are currently present on the island.(see Invasive Species)

Invasive species[edit]

Pearlwort (sagina procumbens)[edit]

In 1998 a number of procumbens pearlwort (sagina procumbens) plants were found on the island which are capable of dramatically transforming the upland plant ecosystem (as it has on the Prince Edward Islands). [15] Eradication efforts are ongoing but are expected to require years of 'concerted effort'. [16]

House mice[edit]

In April 2007 researchers published evidence that predation by introduced house mice on seabird chicks is occurring at levels that might drive the Tristan Albatross and the Atlantic Petrel to extinction.[17] The Royal Society for the Protection of Birds has since been awarded £62,000 by the UK government's Overseas Territories Environment Programme to fund additional research on the Gough Island mice and a feasibility study of how best to deal with them. The grant will also pay for the assessment of a rat problem on Tristan da Cunha island. Trials for a method of eradicating the mice through baiting are ongoing.[18]

Weather station[edit]

A weather station has been operating on Gough Island since 1956. It is operated as part of the network of the South African Weather Service. Because cold fronts approach South Africa from the south-west, the Gough station is particularly important in forecasting winter weather. Initially it was housed in the station at The Glen, but moved to the South Western lowlands of the island in 1963 where weather observations are more accurate.

Human presence[edit]

Each year a new overwintering team arrives by ship (currently the SA Agulhas II) to man the weather station and perform scientific research. The team for a particular year may be termed as "Gough" and an expedition number - e.g. "Gough 58" for 2013 denoting the 58th expedition to Gough Island (the 1956 team were Gough 01). The new team replaces the previous one thereby maintaining a continual human presence on the island.[19] [20]

A team normally consists of:

The team is supplied with enough food to last them for the whole year. People and cargo are landed either by helicopter, from a helideck-equipped supply ship, or by a fixed crane atop a cliff near the station (a place aptly called "Crane Point").

Maps[edit]

See also[edit]

References[edit]

  1. ^ Report on the geological collections made during the voyage of the ... British Museum (Natural History), Walter Campbell Smith, British Museum (Natural History) – 1930 "DIEGO ALVAREZ OR GOUGH ISLAND. By W. Campbell Smith. Gough Island, as it seems to be more usually called, lies about 200 miles south of the Tristan da Cunha group in latitude 40° S., longitude 10° W.1 It is about 8 miles long by 3 ..."
  2. ^ Plants of Gough Island: (Diego Alvarez) Erling Christophersen – 1934
  3. ^ The Antarctic dictionary: a complete guide to Antarctic English – Page 150 Bernadette Hince – 2000 -"I went for adventure. to have fun, Gough Island Gough Island was named I. de Goncalo Alvarez on early maps. after its discoverer. Portuguese navigator Goncalo Alvarez. The name was later corrupted to I. Diego Alvarez. and there was confusion about the locality. It was renamed after Captain Charles Gough of the British barque Richmond. who sighted the island in 1713."
  4. ^ "South African Journal of Science – Gough Island 500 years after its discovery: a bibliography of scientific and popular literature 1505 to 2005". Scielo.org.za. Retrieved 2012-10-25. 
  5. ^ Wace N.M. (1969). "The discovery, exploitation and settlement of the Tristan da Cunha Islands". Proceedings of the Royal Geographical Society of Australasia (South Australian Branch) 10: 11–40. 
  6. ^ Gough's log is preserved in the East India Collection at the British Library. The entry for 3 March 1732 is printed in Gabriel Wright (pub.), "A New Nautical Directory for the East-India and China Navigation", 7th edn, London, 1804, p. 394.
  7. ^ Heaney, J.B., Holdgate, M.W. (1957). The Gough Island Scientific Survey.The Geographical Journal, Vol. 123, No. 1, pp. 20–31
  8. ^ "Gough Island, South Atlantic Ocean". Btinternet.com. Retrieved 2012-10-25. [dead link]
  9. ^ "Gough Island". Sanap.ac.za. Retrieved 2012-10-25. 
  10. ^ "Gough Island Climate Normals 1961−1990". National Oceanic and Atmospheric Administration. Retrieved November 21, 2013. 
  11. ^ "Climate Statistics for Gough Island, South Africa". 20 February 1998. 
  12. ^ Cuthbert, J. & Sommer, E. Population size and trends of four globally threatened seabirds at Gough Island, South Atlantic Ocean. Marine Ornithology 32: 97–103.
  13. ^ Roots, Clive (2006). Flightless birds. Westport, Conn.: Greenwood Press. p. 60. ISBN 0-313-33545-1. Retrieved 2008-03-31. 
  14. ^ "Gough Island". Important Bird Areas factsheet. BirdLife International. 2012. Retrieved 2012-10-25. 
  15. ^ Cooper, J. et al., "Earth, fire and water: applying novel techniques to eradicate the invasive plant, procumbent pearlwort Sagina procumbenss, on Gough Island, a World heritage Site in the South Atlantic", Invasive Species Specialist Group, 2010, Retrieved on 12 February 2014.
  16. ^ Bisser, P. et al., "Strategies to eradicate the invasive plant procumbent pearlwort Sagina procumbens on Gough Island, 2010", Retrieved on 12 February 2014.
  17. ^ R M Wanless, A Angel, R J Cuthbert, G M Hilton and P G Ryan (2007). "Can predation by invasive mice drive seabird extinctions?". Biology Letters 3 (3): 241–244. doi:10.1098/rsbl.2007.0120. PMC 2464706. PMID 17412667. 
  18. ^ R. J. Cuthbert1 , P. Visser et al., "Preparations for the eradication of mice from Gough Island: results of bait acceptance trials above ground and around cave systems", 2011, Retrieved on 12 February 2014.
  19. ^ "South Africa National Antactic Programme - Gough Island Teams", Retrieved 12 February 2014
  20. ^ Chris Bell, "Chris Bell's Blog from Gough 58", Retrieved 12 February 2014

External links[edit]