Map of Ascension Island (click to view full-size)
Background information
Ascension lies on the mid-Atlantic ridge at 7o 57' S, 14o 22' W. The island is extremely isolated, being around 1,200km (750 miles) northwest of its nearest neighbour, Saint Helena. Around 1,100 people live on the island, mainly Saint Helenans, but with a number of American and British citizens as well.
Legislation regarding Impact Assessment
International Conventions
The island of Ascension is included in the UK's ratification of the following international conventions relating to biodiversity protection and/or impact assessment:
- World Heritage Convention
- Ramsar Convention
- Convention on International Trade in Endangered Species
- Convention on Migratory Species
- Convention on Biological Diversity
- International Convention on the Regulation of Whaling
- United Nations Convention to Combat Desertification
National
- Green Mountain (Natural Resources) Protection Ordinance No. 14 1955
- Ascension Land Ordinance, 1967
- Wild Life (Protection) (Ascension) Ordinance Cap 129 1944
- Wild Life (Protection) (Ascension) Regulations 1967
- Endangered Species Control Ordinance 1976
- Conservation Management Plan?
More detailed information on this legislation is available through the legislation pages.
Key development areas and issues
The majority of Ascension's development revolves around the communications industry, with the MoD also using the island as a mid-way link between the UK and the Falkland Islands.
Biodiversity interest
The vegetation of the islands is strongly affected by introduced species, with over 300 introduced species, and only 25 native vascular plants. The majority of these are threatened with extinction, surviving primarily on exposed rock faces and walls in the highest points of the island. Low altitude areas are generally barren, with small areas of grassy tussocks and the endemic Euphorbia origanoides. A list of the endemic species and their threat categorisation (as of 1999) can be found on this page.
Around 311 terrestrial animal species are known from Ascension, although several of these have now been declared extinct. Some 95 of these only are considered indigenous, including two extinct landbird species, a night-heron (Nycticorax sp. nov.) and a flightless rail (Atlantisia elpenor). Of the invertebrates, some 29 are considered endemic (see important species page for further details). No native terrestrial reptiles or amphibians occur, but two species of marine turtle occur: the Green (Chelonia mydas) and the Hawksbill (Eretmochelys imbricata), although the latter appears to be merely a non-breeding visitor. Ascension is considered one of the most important breeding colonies in the world for Green Turtles, with ca. 2,000 breeding each year on around 32 beaches.
The key faunal group on Ascension is birds: the seabird colonies consist of up to a million breeding birds (pairs?) of 11 resident species: four tern spp, three booby spp, two tropicbird spp, one storm petrel, and perhaps most important of all, the Vulnerable Ascension Frigatebird (Fregata aquila). The island and its associated stacks are one of the most important seabird assemblages in the South Atlantic, leading to the designation of two Important Bird Areas here by BirdLife International (see below for more details). The only resident landbirds are all introduced species: Red-necked Spurfowl (Pternistis [Francolinus] afer), Common Myna (Acridotheres tristis), House Sparrow (Passer domesticus), Common Waxbill (Estrilda astrild) and Yellow Canary (Serinus flaviventris).
Key problem species are invertebrates (predating native invertebrate species), Mexican thorn tree (Prosopis juliflora) - outcompetes native plants, contributes to soil erosion, Common Myna (predation of SooTe chicks in particular), and cat/rat predation of turtle and bird juveniles. Control programmes having positive impact (Varnham 2006).
Further information on the important species of the islands can be found here.
Protected Areas
Green Mountain's forests and water supply are protected under the Green Mountain (Natural Resources) Protection Ordinance, Boatswainbird Island is a designated SSSI (1981) and two nature reserves have been declared at Mars Bay and Hummock Point (1997)
The entire island is also a proposed Ramsar site.
Although not designating any form of protection, the main island of Ascension and the small islet of Boatswainbird Island are also recognised as Important Bird Areas by BirdLife International for their breeding seabird populations, in particular for the populations of Red-billed Tropicbird (Phaethon aethereus), Ascension Frigatebird (Fregata aquila), Sooty Tern (Onychoprion fuscata) and Black Noddy (Anous minutus) on Ascension, and of Band-rumped Storm-petrel (Oceanodroma castro), Red-billed Tropicbird (Phaethon aethereus), White-tailed Tropicbird (Phaethon lepturus), Ascension Frigatebird (Fregata aquila), Masked Booby (Sula dactylatra) and Black Noddy (Anous minutus) on Boatswainbird Island (see important species page for further details).
A recommendation was passed by the International Council for Bird Preservation (ICBP) 1990 World Conference, that the UK Government designate the whole of Ascension Island a protected natural area, and implement the removal of introduced species, cats in particular. A feral cat eradication programme is nearing completion, resulting in the return of several breeding seabird species (BirdLife, 2003)
Detailed information on protected areas can be found here.