Ascension Island: mainland and stacks - Marine

Country/territory: St Helena (to UK)

IBA criteria met: -
For more information about IBA criteria, please click here

Area: 2,327,758 ha

Site description (2012 baseline)
This Marine IBA is identified using seaward extensions around breeding colonies. It originates from the St Helena (to UK) Exclusive Economic Zone (EEZ) and falls within the Atlantic, Southeast FAO ocean region. The site covers an area of 23278 km2 and is 1231 km away from the closet coastline. The depth ranges from 0 to 4078 m, with a mean annual wind speed of 2.01 m/s, mean annual sea surface temperature falls between 25.55 and 25.91 °C and mean annual chlorophyll-a concentrations found to range between 0.08 and 0.13 mg/m3.

Key biodiversity
6 species trigger IBA criteria at this Marine IBA. Seaward extensions around breeding colony; Ascension Island: mainland and stacks include key near-colony areas for breeding populations of Black Noddy (LC) 15000-24000 breeding pairs, Ascension Frigatebird (VU) 18000-18000 breeding pairs, Red-billed Tropicbird (LC) 1665-1665 breeding pairs, White-tailed Tropicbird (LC) 3000-3000 breeding pairs, Sooty Tern (LC) 232800-465600 breeding pairs and Masked Booby (LC) 390-3315 breeding pairs.

Recommended citation
BirdLife International (2023) Important Bird Area factsheet: Ascension Island: mainland and stacks - Marine. Downloaded from on 26/09/2023.