This small (6.5 ha) coastal island lies 1.4 km from Namibia’s Diamond Coast, c.50 km north of Lüderitz. The island is circular, mostly flat and unvegetated, and since rocky outcrops reach only 7 m, sea spray covers much of the island during storms. It is now completely surrounded by a sea wall to prevent seals from hauling out and disturbing the birds. Repeated guano scraping since the 1840s, when guano deposits were over 20 m thick, has left the rocky island-floor entirely exposed. Sandy stretches exist on the eastern side of the island. Ichaboe lies in the heart of the one of the strongest upwelling systems in the world, caused by the consistently strong longshore winds. The upwellings bring nutrients to the surface where they enhance phyto- and zooplankton blooms that are the basis for the rich abundance of fish on which the birds thrive. Rainfall is minimal (less than 10 mm per year), but coastal fog and storms often envelop the island.
See Box for key species. Ichaboe Island is one of the most important and densely packed coastal seabird breeding islands in the world. It regularly supports over 50,000 seabirds of at least eight species, including large numbers of Spheniscus demersus, Morus capensis, Phalacrocorax capensis, P. neglectus and P. coronatus. Smaller numbers of Larus dominicanus and Haematopus moquini also breed. This island is the most important location for Phalacrocorax neglectus in the world, holding a massive 65% of this globally near-threatened species’s population. During the last 20 years the global population has declined from 9,000 pairs to less than 5,000 pairs, of which total Namibia holds c.4,000 pairs. Ichaboe also holds about 4% of the world breeding population of Phalacrocorax coronatus. The island may also harbour thousands of roosting terns, particularly Sterna hirundo and Chlidonias niger.
Non-bird biodiversity: Whales sighted here include Megaptera novaeangliae (VU) and Eubalaena australis (LR/cd). The cetaceans Lagenorhynchos obscurus (DD), Tursiops truncatus (DD) and the endemic Cephalorhynchus heavisidii (DD) are visitors to the island's waters.
BirdLife International (2019) Important Bird Areas factsheet: Ichaboe Island. Downloaded from http://www.birdlife.org on 23/10/2019.