Ascension Island Seabirds Definitive
Ascension Island is the most important seabird breeding site in the tropical Atlantic and is one of the most important warm water seabird stations in the world. This new definitive series includes each of the 11 species of breeding seabird found ion Ascension. The present seabird population is thought to be only a fraction of what it was prior to man’s colonisation of the island in 1815, when there are estimated to have been millions of seabirds nesting in large colonies on the mainland. The introduction of cats to Ascension Island in the 1800s led to rapid population declines of seabirds nesting on the mainland. The relatively small surviving populations were limited to inaccessible cliff ledges and offshore stacks, the largest of which is Boatswain Bird Island. In 2002, a feral cat control programme was initiated and the island was declared feral cat free in 2004. Seabird recolonisation of accessible mainland sites was first recorded in May 2002 and numbers have increased steadily since. The first species to recolonise were masked booby, brown booby, brown noddy and white-tailed tropicbird. However, it took ten years for Ascension’s endemic frigatebird to return to nest on the mainland, with the first two mainland nests found in 2012. The numbers nesting on the mainland have increased to 1632 in 2025 and hopefully this will continue to increase. 15p Band Rumped Storm Petrel The smallest breeding Seabird on Ascension, storm petrels nest in burrows on Boatswain Bird Island Sanctuary. Their dark brown plumage is broken up by a striking white band on their rump and pale wing bars. Storm petrels are best seen offshore from boats or from Hummock Point Nature Reserve as they commute to their nest sites. 20p Black Noddy, 25p Brown Noddy The brown noddy is noticeably larger than the darker black noddy and the pale forehead and crown of the black noddy is more pronounced. Brown noddies nest singularly or in small colonies on rocky outcrops around the coast while black noddies are restricted to remote cliff ledges where they nest colonially. Brown noddies can sometimes be seen nesting at the Mars Bay Nature Reserve but are most numerous on offshore stacks and the adjacent coastline or on the Letterbox Peninsula. Black noddies can be observed at Pillar Bay or around the Letterbox Nature Reserve with most nesting on Boatswain Bird Island Sanctuary. 30p Sooty Tern Sooty terns have black plumage on their backs and white underneath, with a deeply forked tail. They are locally known as Wideawakes because of their loud call, which means they will often be heard before they are seen, particularly in breeding season. They nest colonially, historically returning to the island every 10 months to breed in vast numbers on the Wideawake fairs at Mars Bay and Waterside. Monitoring this vast colony is tricky but the Conservation Department are conducting drone surveys to produce accurate population counts. They can be seen at Mars Bay or Waterside Nature Reserves (during breeding season). 40p Fairy Tern Also known as White terns, these small white, inquisitive terns will often follow visitors, particularly during walks around Green Mountain and off Middleton’s Path. This species tends to remain close to the island all year round and can often be seen in pairs performing synchronised aerobatics. The best places to find them are Green Mountain National Park and Letterbox Nature Reserve. 50p Red Footed Booby, 60p Brown Booby, 65p Masked Booby Three species of booby nest around Ascension. The largest and most numerous is the Masked booby which is predominately white with black trailing edges to the wings and tail. When nesting, they create a distinct guano circle around the nest site. Males can be identified by their whistle while females make a grunting noise. The smallest Ascension booby is the Brown booby, nesting on the Letterbox and South Coast Nature Reserves. They are easily distinguished by their brown plumage with adults having a crisp white belly and dull yellow bill and feet. Red-footed boobies nest on the cliffs of Boatswain Bird Island Sanctuary and on the Letterbox Nature Reserve. Two colour morphs are found on Ascension- the paler may be confused with masked boobies in flight however red-foots have a white tail. The brown morph is easy to identify with their bright red feet. The best places to see these birds are Boatswain Bird Island Sanctuary and the Letterbox and South Coast Nature Reserves. £1 Yellow-billed Tropicbird, £1.30 Red-billed Tropicbird Both of these species can most easily be seen in flight; their strikingly elongated central tail feathers and loud calls make them easily identifiable. Tropicbirds are mostly white with a black eye stripe. The yellow-billed tropicbird is smaller, more delicate and is mostly white with prominent diagonal black bars on the wings. In contrast, the red-billed tropicbird has fine black barring on its back. These hole-nesting species are often easy to miss when scanning a cliff as all that is visible is the long tail streamers. Can be seen along the Northwest coast and Boatswain Bird Island Sanctuary. £2.50 Female/Juvenile Frigatebird, £5 Male Frigatebird Endemic to Ascension, this distinctive seabird with long wings and a deeply forked tail is most often observed in flight. Adults are predominately dark with males displaying a distinctive red throat pouch during the breeding season. Females have a blue ring around their eyes. Juveniles can be identified by their white head and belly. Frigatebirds are highly adapted to an aerial lifestyle; they are very light for their size and fly very efficiently using thermals to soar over vast distances. Their plumage is not waterproof so they never land on the ocean but instead use their aerial agility to pluck food from the surface of the ocean or steal from other seabirds. The downside of adaptation to life on the wing is that they have very short legs suited more to perching than walking even short distances. This species nests on Boatswain Bird Island Sanctuary and adjacent Letterbox Nature Reserve. Males attract females to mate with by inflating their large red throat pouch and vibrating their wings. Females lay a single white egg on the ground, with only a few feathers or pieces of vegetation to mark the nest. We acknowledge with thanks the help and assistance of the Ascension Island Government Conservation and Fisheries Directorate. High resolution images for this stamp issue can be found below: SetFirst Day Cover 1First Day Cover 2
