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ISLAND DIRECTORY
Islands of Tristan da Cunha Islands
Gough [1249]
Group: Archipelago: Tristan da Cunha Islands
Country: United Kingdom - Tristan da Cunha Region: South Atlantic
Lat: 40.32º S Long : 9.94º W
Area: 66.6 sq. km Altitude: 910 m
Shoreline: 37.6 km (scale 1:1000000) Coastal Index: 0.5646
Depth to nearest land: 3000 m
Nearest island: 350 km group: 2800 km
Nearest continent: Africa Distance: 2800 km Isolation Index: 125
ISLAND TYPE: volcanic Natural Protection Indicator: 1
GEOLOGY/SOILS:
Volcano with rounded hills on central plateau, ridges and steep valleys
of
basaltic lavas to north and east, lowlands in south, coastal cliffs,
rivers
CLIMATE: wet temperate 11.3øC, 3397 mm (296 days/yr)
WATER BALANCE: ample water
CATASTROPHIC THREATS: volcanic eruptions, fire
Threat Indicator: 2
ECOSYSTEMS: Number of Ecosystems - Terrestrial: 5 Marine: 1
Grasses Spartina arundinacea and Poa flabellata on coastal cliffs; fern
bush
to 300 m; wet heath 300-600 m; sparse montane vegetation above 600 m;
peat
bogs in upland valleys; rocky shores
| SPECIES NUMBERS: |
Total |
Endemic |
Threatened (EVRI) |
| Plants |
63 |
36 |
1 |
| Butterflies |
0 |
0 |
0 |
| Land snails |
0 |
0 |
0 |
| Rept/Amphib |
0 |
0 |
0 |
| Land birds |
0 |
2 |
2 |
| Mammals |
2 |
0 |
0 |
SPECIES OF CONSERVATION INTEREST:
Plants:
27 ferns, 15 endemic
35 native higher plants, 21 endemic, 17 introduced
Ranunculus caroli, Rare
Invertebrates:
81 species, 8 endemic, 14 group endemics, 19 introductions
10 spiders
Reptiles/amphibians:
none
Birds:
23 breeding species of land and sea birds
Gallinula comeri (nesiotis) (Gough Moorhen or Island Rail) endemic,
2000-
3000 pairs (1985), Rare (RDB)
Rowettia goughensis (Gough Island Bunting) endemic, 200 pairs (1974),
Rare
(RDB)
20 breeding seabirds, including:
Eudyptes moseleyi (Northern Rockhopper Penguin), 90000 breeding pairs
Diomedia exulans dabbenena (Wandering Albatros) main breeding area
Diomedia chlororhynchos chlororhynchos (Yellow-nosed Albatross) group
endemic
Puffinus gravis (Great Shearwater) group endemic, exploited
Pterodroma incerta (Atlantic Petrel) group endemic
Mammals:
Arctocephalus tropicalis tropicalis (Amsterdam Island Fur Seal)
abundant,
13000 (1956) and increasing
Mirounga leonina (Elephant Seal) breeding, 200-300 (1956) and
increasing
SPECIES RICHNESS:
poor
ENDEMISM: Terrestrial: Terrestrial Endemism Indicator - Island: 2 Group: 3
plants,2 birds, invertebrates
Marine endemic species: 0
Marine Endemism Indicator - Island: 0 Group: 0
SPECIAL FEATURES : Special Features Indicator - Terrestrial: 2 Marine: 0
major seabird rookeries seal colonies
INVASIVE SPECIES: Invasive Species Indicator: 2
mice, 17 introduced plants
HUMAN OCCUPATION: Inhabited, staff of weather station
Population: 8 (1986) Density: 0.1 persons/sq. km
Growth Rate: 0.0%/yr Stable
Major Human Activities: meteorology
HUMAN IMPACTS:
Conservation support: tenure, government support, legislation
PROTECTED AREAS: Protected Area Coverage Indicators - Terrestrial: 7 Marine: 0
Number: 1 Area: Terrestrial: 66.6 sq. km Marine: 0 sq. km
Wildlife Reserve
Proposed as World Heritage site
DATA RELIABILITY: good Data Rel. Indicator: 3
HUMAN IMPACT INDEX HI: 2
CONSERVATION IMPORTANCE INDEX CI-Terrestrial: 17 High
CI-Marine: 4 Low
REFERENCES:
Last updated: 15/09/90
Inaccessible [1470]
Group: Tristan Group Archipelago: Tristan da Cunha Islands
Country: United Kingdom - Tristan da Cunha Region: South Atlantic
Lat: 37.19º S Long : 12.44º W
Area: 20.0 sq. km Altitude: 600 m
Depth to nearest land: 3000 m
Nearest island: 40 km group: 2800 km
Nearest continent: Africa Distance: 2800 km Isolation Index: 112
ISLAND TYPE: volcanic Natural Protection Indicator: 2
GEOLOGY/SOILS:
Remnant of eroded volcano, with thin basaltic lava flows up to 6 million
years
old; ravines and gullies inland, steep coastal cliffs 155 to 490 m high
CLIMATE: wet temperate
CATASTROPHIC THREATS: volcanic eruptions
Threat Indicator: 1
ECOSYSTEMS: Number of Ecosystems - Terrestrial: 4 Marine: 1
Tussock grass (Spartina arundinacea) on rocky ground, fern bush on wet
peaty
plateau with Phylica arborea thicket in gullies, Empetrum and mossy
Scirpus
heath on highest ground, freshwater bogs with Azolla filiculoides; rocky
shores
| SPECIES NUMBERS: |
Total |
Endemic |
Threatened (EVRI) |
| Plants |
64 |
37 |
0 |
| Butterflies |
0 |
0 |
0 |
| Land snails |
0 |
0 |
0 |
| Rept/Amphib |
0 |
0 |
0 |
| Land birds |
4 |
1 |
3 |
| Mammals |
0 |
0 |
0 |
SPECIES OF CONSERVATION INTEREST:
Plants:
64 native species including 20 endemic flowering plants and 17 endemic
ferns
22 introduced species
Invertebrates:
48 native species, 10 introduced
Birds:
23 breeding species
Atlantisia rogersi (Inaccessible Rail) endemic, estimates range from
1,000
to 10,000, Rare (RDB)
Diomedia chlororhynchos chlororhynchos (Yellow-nosed Albatross) group
endemic
Nesocichla eremita gordoni (Tristan Thrush) endemic subspecies
Nesospiza acunhae (Tristan Bunting) group endemic, Rare (RDB)
Nesospiza wilkinsi dunnei (Grosbeak Bunting) endemic subspecies, Rare
(RDB)
Pterodroma incerta (Atlantic Petrel) group endemic
Puffinus gravis (Great Shearwater) group endemic, exploited
Mammals:
Arctocephalus tropicalis tropicalis (Fur Seal) native, increasing
Mirounga leonina (Elephant Seal) native, increasing
SPECIES RICHNESS:
Species Richness Indicator - Terrestrial: 1 Marine: 0
poor
ENDEMISM: Terrestrial: Terrestrial Endemism Indicator - Island: 2 Group: 3
plants and 1 bird
Marine endemic species: 0
Marine Endemism Indicator - Island: 0 Group: 0
SPECIAL FEATURES : Special Features Indicator - Terrestrial: 1 Marine: 0
seabird rookery
INVASIVE SPECIES: Invasive Species Indicator: 0
no introduced mammals
HUMAN OCCUPATION: Uninhabited, visited occasionally
Population: 0 Density: 0.0 persons/sq. km
Major Human Activities: strict nature reserve, seabird collecting
HUMAN IMPACTS:
Cattle, sheep, goats, pigs and dogs formerly introduced, but none
remain; much
of tussock vegetation destroyed deliberately by fire in 1909; some
harvesting
of seabirds by local islanders. Administered through St Helena.
Conservation support: tenure, government support, legislation
PROTECTED AREAS: Protected Area Coverage Indicators - Terrestrial: 7 Marine: 0
Number: 1 Area: Terrestrial: 20.0 sq. km Marine: 0 sq. km
Island designated as a reserve in 1976
DATA RELIABILITY: good Data Rel. Indicator: 3
CONSERVATION IMPORTANCE INDEX CI-Terrestrial: 21 Very high
CI-Marine: 4 Low
REFERENCES:
Johnson, Timothy H. 1989. Unpublished ICBP profiles of Atlantic
islands.
Last updated: 09/09/90
Nightingale - including Stoltenhoff, Middle [1624]
Group: Tristan Group Archipelago: Tristan da Cunha Islands
Country: United Kingdom - Tristan da Cunha Region: South Atlantic
Lat: 37.39º S Long : 12.51º W
Area: 3.0 sq. km Altitude: 400 m
Depth to nearest land: 3000 m
Nearest island: 22 km group: 2800 km
Nearest continent: Africa Distance: 2800 km Isolation Index: 111
ISLAND TYPE: volcanic Natural Protection Indicator: 1
GEOLOGY/SOILS:
Trachyte lava flows, oldest rocks 18 million years old,
recent volcanic activity 3600 years ago
CLIMATE: wet temperate mean 15øC, 1700 mm/year
CATASTROPHIC THREATS: volcanic eruption
Threat Indicator: 1
ECOSYSTEMS: Number of Ecosystems - Terrestrial: 1 Marine: 1
Dense tussock grass; rocky shores with Macrocystis pyrifera
| SPECIES NUMBERS: |
Total |
Endemic |
Threatened (EVRI) |
| Plants |
0 |
0 |
0 |
| Butterflies |
0 |
0 |
0 |
| Land snails |
0 |
0 |
0 |
| Rept/Amphib |
0 |
0 |
0 |
| Land birds |
16 |
2 |
0 |
| Mammals |
2 |
0 |
0 |
SPECIES OF CONSERVATION INTEREST:
Plants:
6 introduced species
Invertebrates:
low numbers, high endemism
Birds:
16 breeding species
Puffinus gravis (Great Shearwater) largest world population (4-5
million)
Diomedia chlororhynchos chlororhynchos (Yellow-nosed Albatross) group
endemic
Nesocichla eremita procax (Tristan Thrush) endemic subspecies
Nesospiza acunhae (Tristan Bunting) group endemic, Rare (RDB)
Nesospiza wilkinsi wilkinsi (Grosbeak Bunting) endemic subspecies,
Rare
(RDB)
Pterodroma incerta (Atlantic Petrel) group endemic
Puffinus gravis (Great Shearwater) group endemic, exploited
Mammals:
Arctocephalus tropicalis tropicalis (Fur Seal) native, breeding,
increasing
Mirounga leonina (Elephant Seal) native, increasing
SPECIES RICHNESS:
Species Richness Indicator - Terrestrial: 1 Marine: 0
poor
ENDEMISM: Terrestrial: Terrestrial Endemism Indicator - Island: 1 Group: 3
2 birds, some invertebrates
Marine endemic species: 0
Marine Endemism Indicator - Island: 0 Group: 0
SPECIAL FEATURES : Special Features Indicator - Terrestrial: 2 Marine: 0
major seabird rookery, seal rookery
INVASIVE SPECIES: Invasive Species Indicator: 1
6 introduced plants
HUMAN OCCUPATION: Uninhabited, visited occasionally
Population: 0 Density: 0.0 persons/sq. km
HUMAN IMPACTS:
Administered through St Helena
Conservation support: tenure, government support, legislation
PROTECTED AREAS: Protected Area Coverage Indicators - Terrestrial: 7 Marine: 0
Number: 1 Area: Terrestrial: 3.0 sq. km Marine: 0 sq. km
Island effectively protected as strict nature reserve
DATA RELIABILITY: partial Data Rel. Indicator: 2
HUMAN IMPACT INDEX HI: 1
CONSERVATION IMPORTANCE INDEX CI-Terrestrial: 11 Moderate
CI-Marine: 3 Low
REFERENCES:
Last updated: 16/05/89
Tristan da Cunha [910]
Group: Tristan Group Archipelago: Tristan da Cunha Islands
Country: United Kingdom - Tristan da Cunha Region: South Atlantic
Lat: 37.12º S Long : 12.29º W
Area: 103.2 sq. km Altitude: 2060 m
Shoreline: 39.6 km (scale 1:1000000) Coastal Index: 0.3837
Depth to nearest land: 3000 m
Nearest island: 35 km group: 350 km
Nearest continent: Africa Distance: 2800 km Isolation Index: 78
ISLAND TYPE: active volcanic Natural Protection Indicator: 0
GEOLOGY/SOILS:
Active volcano, eruption 1961-62
CLIMATE: wet temperate 14.5øC, 1676 mm
CATASTROPHIC THREATS: volcanic eruptions (1961)
Threat Indicator: 1
ECOSYSTEMS: Number of Ecosystems - Terrestrial: 5 Marine: 1
Tussock grassland (Spartina arundinacea) along coast; fern-bush (Phylica
arborea and Blechnum palmiforme) above, eliminated from grazed
north-west and
southern lowlands but mainly undamaged on east; wet heath, moss and
feldmark
on upper slopes; peat mires (Sphagnum) on lower slopes in depressions;
four
crater lakes; rocky shores
| SPECIES NUMBERS: |
Total |
Endemic |
Threatened (EVRI) |
| Plants |
93 |
54 |
6 |
| Butterflies |
1 |
0 |
0 |
| Land snails |
2 |
2 |
0 |
| Rept/Amphib |
0 |
0 |
0 |
| Land birds |
15 |
3 |
0 |
| Mammals |
2 |
0 |
0 |
SPECIES OF CONSERVATION INTEREST:
Plants:
58 native flowering plants, 34 endemic, 6 Rare
Phylica arborea
35 native ferns, 20 endemic
150 introduced vascular plants
Insects/Invertebrates:
62 native species, 4 endemic
57 introduced invertebrates
1 breeding butterfly
Dimorphinoctua (moth) endemic species
Protoleucania (moth) endemic species
Tristania (mollusc) endemic genus
Succinea flexilis (mollusc) endemic
Reptiles/amphibians:
none
Birds:
15 breeding species of land and sea birds
Nesocichla eremita eremita (Tristan Thrush) endemic
Nesospiza acunhae (Tristan Bunting) endemic
Nesospiza wilkinsi (Tristan Large-billed Bunting) endemic
Diomedia chlororhynchos chlororhynchos (Yellow-nosed Albatross) group
endemic
Gallinula comeri (Gough Moorhen) introduced from Gough, Rare (RDB)
Pterodroma incerta (Atlantic Petrel) group endemic
Puffinus gravis (Great Shearwater) group endemic, exploited
Mammals:
Arctocephalus tropicalis tropicalis (Fur Seal) native, increasing
Mirounga leonina (Elephant Seal) native, increasing
SPECIES RICHNESS:
Species Richness Indicator - Terrestrial: 1 Marine: 0
poor
ENDEMISM: Terrestrial: Terrestrial Endemism Indicator - Island: 3 Group: 3
many plants, 3 birds
Marine endemic species: 0
Marine Endemism Indicator - Island: 0 Group: 0
SPECIAL FEATURES : Special Features Indicator - Terrestrial: 2 Marine: 0
seabird rookery seal colonies
INVASIVE SPECIES: Invasive Species Indicator: 3
many
HUMAN OCCUPATION: Inhabited
Population: 296 (1988) Density: 2.9 persons/sq. km
Growth Rate: -0.1%/yr Decreasing
Major Human Activities: crayfish, postage stamps, handicrafts
HUMAN IMPACTS:
Administered through St Helena
Conservation support: tenure, legislation
PROTECTED AREAS: Protected Area Coverage Indicators - Terrestrial: 7 Marine: 0
Number: 1 Area: Terrestrial: 103.2 sq. km Marine: 0 sq. km
Jews Point Sanctuary created 1979
DATA RELIABILITY: good Data Rel. Indicator: 3
HUMAN IMPACT INDEX HI: 3
CONSERVATION IMPORTANCE INDEX CI-Terrestrial: 21 Very high
CI-Marine: 2 Low
REFERENCES:
Clark, M.R. and Dingwall, P.R. 1985. Conservation of islands in the
Southern
Ocean: a review of the protected areas of Insulantarctica. IUCN,
Gland and
Cambridge. 193 p.
Last updated: 16/05/89
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Page last updated: 09/05/10