Ascension Island: Masked Booby

The Letterbox Nature Reserve on the South-East of Ascension was designated in 2003 to protect nesting seabirds. This followed a successful feral cat eradication which released the birds from predation pressures. Since the eradication, the local seabird population has risen each year and the protected area network review identified nesting sites which were outside of the original Nature Reserve boundary.

The Masked Booby (Sula dactylatra) had colonized new nesting sites on the Western edge of the reserve boundary and along the Ascension South coast- an area which was historically important for this species before the reign of the cat. The Masked Booby is a charismatic seabird with sharp yellow eyes and feisty personalities. They are generally monogamous, taking the same partner each year to nest.

Masked boobies lay 2 eggs in a scrape on the ground, incubating the eggs for around 40 days. Once hatched, only the larger chick will survive to fledge which can take over 100 days. Fledglings are visibly different from the adults with a brown head and body compared to the adults’ crisp white body with black wing ridges. It takes around 10 months for the fledgling plumage to be moulted into the adult phase. The masked booby is an apex predator and on Ascension they are surrounded by thousands of miles of open ocean, making them the master of both land and sea.

In 2023, a public consultation and expert recommendations were sought and together Ascension Island agreed to expand the Letterbox Nature Reserve to protect Masked Boobies and create new protected areas for the conservation of other important wildlife. For further information please see the Ascension Island Government website: www.ascension.gov.ac/conservation