There's an island (Ichaboe) that lies on West Africa's shore,
Where penguins have lived since the flood or before,
And raised up a hill there, a mile high or more,
This hill is all guano, and lately 'tis shown,
That finer potatoes and turnips are grown
By means of this compost, than ever were known;
And the peach and the nectarine, the apple, the pear,
Attain such a size, that the gardeners stare,
And cry, "Well, I never saw fruit like that 'ere!"
One cabbage thus reared, as a paper maintains,
Weighed twenty-one stone, thirteen pounds and six grains,
So no wonder Guano celebrity gains.
- Ex-member of the Committee (1845)
Ichaboe Island is a small island (6.5 ha), about 1.5 km offshore, 48 km north of Lüderitz, opposite the restricted diamond area (Sperrgebiet). This flat island is partly protected from thundering waves crashing into it by a reef just to the west of the island. A group of seals live permanently on the reef, and although a few pups are born there every year, it is not strictly speaking a fully-fledged breeding colony.
Historically, Ichaboe Island was used extensively for sealing. The interest shifted when Captain B. Morrell landed on Ichaboe Island in 1828 and reported "birdsí manure to the depth of twenty-five feet". This set off the guano rush with Ichaboe Island the main focus. Large-scale scraping began in 1843, with the peak during 1845, when no less than 450 boats lay off Ichaboe Island and an estimated 6 000 men scraped the island. Guano has been taken off the island regularly since then. Although concessions were granted to Mercury Island, Ichaboe Island and Possession Island during the 1980s, only Ichaboe continued to be scraped. The latest scrape took place during the winter of 2000, under the strict supervision of the island's chief technician, to ensure minimum disturbance to the birds. A high wall was built around the entire perimeter of the island with a few entry points for penguins to gain access to the breeding colonies. The wall was put up to prevent guano from being blown into the sea. Ichaboe Island is managed by the Ministry of Fisheries and Marine Resources and is permanently staffed. Activities on the island include regular monitoring of the seabird population. Owing to the high sensitivity of the island, landing on the island is prohibited without a permit issued by the Ministry.
Ichaboe Island supports by far the largest number of Cape Gannets in Namibia. Numbers are declining at an alarming rate, however. Reasons for this decline are thought to be overfishing and entanglement resulting from an increase in long-lining activities. In terms of African Penguin numbers, Ichaboe Island is the second most important island in Namibia. Since 1994, when there were almost 10 000 adult individuals, numbers have steeply declined, and in 2000 only 6 500 were counted. Reasons for this decline are not entirely clear, but lack of prey appears to be a possibility. Some penguins appear to have migrated north to Mercury Island, but penguins "gained" on Mercury Island do not offset the losses on Ichaboe Island.
A large number of Cape Cormorants as well as a number of Crowned Cormorants nest on the island. A few African Black Oystercatchers breed on the island. Three chicks fledged in April and May 2001.
See more photos at: Ringing visit to Namibian islands, January 2003