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ISLAND DIRECTORY
Islands of Chagos Archipelago (Brit Indian Oc Terr)
Diego Garcia [1244]
Group: Archipelago: Chagos Archipelago
Country: United Kingdom - Chagos Archipelago BIOT
Lat: 6.57º S Long : 72.42º E
Area: 37.6 sq. km Altitude: 5 m
Shoreline: 113.4 km (scale 1:500000) Coastal Index: 3.0160
Land < 5 m elevation: 37.6 sq. km Sea level rise risk: 9
Depth to nearest land: 3000 m
Nearest island: 90 km group: 650 km
Nearest continent: Asia Distance: 1800 km Isolation Index: 77
ISLAND TYPE: atoll Natural Protection Indicator: 0
GEOLOGY/SOILS:
Atoll with continuous land rim of 60 km and average height under 2 m;
lagoon
21 by 11 km, openings with 3 small islands to north
CLIMATE: wet tropical 27øC, 2290-2540 mm/year
CATASTROPHIC THREATS: earthquakes (1983)
Threat Indicator: 0
ECOSYSTEMS: Number of Ecosystems - Terrestrial: 5 Marine: 3
Broadleaved woodland with Ficus, Morinda and Terminalia (especially on
smaller
islands), Casuarina woodland, mixed coconut woodland, Scaevola scrub,
marsh;
windward and leeward atoll reefs, lagoon
Percent shoreline: Coral Reef: 99% Mangrove: 0%
| SPECIES NUMBERS: |
Total |
Endemic |
Threatened (EVRI) |
| Plants |
0 |
0 |
0 |
| Butterflies |
0 |
2 |
0 |
| Land snails |
24 |
0 |
0 |
| Rept/Amphib |
4 |
0 |
0 |
| Land birds |
0 |
0 |
0 |
| Mammals |
0 |
0 |
0 |
SPECIES OF CONSERVATION INTEREST:
Plants:
6 ferns, 4 mosses
193 higher plants including introductions and cultivated species
Insects:
46 species, including:
Hypolimnas bolina euphorioides (butterfly) group endemic
Junonia villida chagoensis (butterfly) group endemic
Other invertebrates:
24 land molluscs
Reptiles/Amphibians:
2 geckos
2 mud turtles ?
Green turtles, 300 nesting females annually
Hawksbill turtles, 300 nesting females annually
Birds:
Butorides striatus albolimbatus* (Green Heron) endemic race
Streptopelia picturata chuni (Madagascar Turtle Dove) status uncertain
50 seabird species, 13 breeding
Marine life:
220 scleractinian corals, including:
Ctenella chagius (Chagos Brain Coral) endemic
384 molluscs
702 fish
SPECIES RICHNESS:
Species Richness Indicator - Terrestrial: 2 Marine: 4
moderate; rich marine
ENDEMISM: Terrestrial: Terrestrial Endemism Indicator - Island: 1 Group: 1
group endemic butterflies,bird
Marine endemic species: 0
Marine Endemism Indicator - Island: 0 Group: 1
1 group endemic coral
SPECIAL FEATURES : Special Features Indicator - Terrestrial: 2 Marine: 1
major seabird rookery, turtle nesting area
most extensive undisturbed reefs in Indian Ocean
INVASIVE SPECIES: Invasive Species Indicator: 4
feral cats, donkeys, chickens; rats, degrading isl
HUMAN OCCUPATION: Inhabited, military occupants only
Population: 0 Density: 0.0 persons/sq. km
Major Human Activities: military base
HUMAN IMPACTS:
Former population of 2000 removed between 1965 and 1973; military
population
only; major UK/US military base, airfield and port facilities, requiring
construction and dredging
Accessibility: port, airport
Conservation support: access strictly controlled
PROTECTED AREAS: Protected Area Coverage Indicators - Terrestrial: 0 Marine: 0
Number: 4 Area: Terrestrial: 0.0 sq. km Marine: 0 sq. km
Three islands at lagoon entrance are bird sanctuaries
About half of island rim is restricted area
DATA RELIABILITY: Data Rel. Indicator: 2
HUMAN IMPACT INDEX HI: 4
CONSERVATION IMPORTANCE INDEX CI-Terrestrial: 9 Moderate
CI-Marine: 14 Moderate
REFERENCES:
Topp, J.M.W. 1988. An annotated check list of the flora of Diego
Garcia,
British Indian Ocean Territory. Atoll Research Bulletin 313. October
1988
Last updated: 10/08/90
Great Chagos Bank - incl: Egmont,Danger,Eagle,Three Brothers [1588]
Group: Archipelago: Chagos Archipelago
Country: United Kingdom - Chagos Archipelago BIOT
Lat: 6.00º S Long : 71.52º E
Area: 0.0 sq. km Altitude: ? m
Depth to nearest land: 3000 m
Nearest island: 50 km group: 600 km
Nearest continent: Asia Distance: 1750 km Isolation Index: 73
ISLAND TYPE: atoll Natural Protection Indicator: 1
CLIMATE: wet tropical
ECOSYSTEMS: Number of Ecosystems - Terrestrial: 3 Marine: 3
Atoll forest, scrub, marsh; windward and leeward atoll reefs and lagoon
Percent shoreline: Coral Reef: 99% Mangrove: 0%
Species Richness Indicator - Terrestrial: 2 Marine: 4
ENDEMISM: Terrestrial: Terrestrial Endemism Indicator - Island: 0 Group: 1
Marine endemic species: 0
Marine Endemism Indicator - Island: 0 Group: 1
SPECIAL FEATURES : Special Features Indicator - Terrestrial: 2 Marine: 1
seabird rookery turtle nesting area
world's largest atoll in terms of area
INVASIVE SPECIES: Invasive Species Indicator: 4
HUMAN OCCUPATION: Uninhabited, population evacuated
Population: 0 Density: 0.0 persons/sq. km
Conservation support: tenure, government support
DATA RELIABILITY: Data Rel. Indicator: 2
HUMAN IMPACT INDEX HI: 4
CONSERVATION IMPORTANCE INDEX CI-Terrestrial: 9 Moderate
CI-Marine: 15 High
Last updated: 01/02/89
Perhos Banhos [1590]
Group: Archipelago: Chagos Archipelago
Country: United Kingdom - Chagos Archipelago BIOT
Lat: 5.30º S Long : 72.00º E
Area: 0.0 sq. km Altitude: ? m
Depth to nearest land: 3000 m
Nearest island: 30 km group: 600 km
Nearest continent: Asia Distance: 1750 km Isolation Index: 72
ISLAND TYPE: atoll Natural Protection Indicator: 2
CLIMATE: wet tropical
ECOSYSTEMS: Number of Ecosystems - Terrestrial: 1 Marine: 3
Windward and leeward atoll reefs and lagoon
Species Richness Indicator - Terrestrial: 0 Marine: 5
ENDEMISM: Terrestrial: Terrestrial Endemism Indicator - Island: 0 Group: 0
Marine endemic species: 0
Marine Endemism Indicator - Island: 0 Group: 1
HUMAN OCCUPATION: Uninhabited
Population: 0 Density: 0.0 persons/sq. km
Conservation support: tenure, government support
DATA RELIABILITY: Data Rel. Indicator: 2
CONSERVATION IMPORTANCE INDEX CI-Terrestrial: 2 Low
CI-Marine: 17 High
Last updated: 01/02/89
Salomon [1589]
Group: Archipelago: Chagos Archipelago
Country: United Kingdom - Chagos Archipelago BIOT: Indian
Lat: 5.27º SLong: 72.42º E
Area: 0.0 sq. km Altitude: ? m
ISLAND TYPE: atoll
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Page last updated: 09/05/10