Saint Helena, Ascension and Tristan da Cunha
This British Overseas Territory comprises several extremely remote volcanic islands in the South Atlantic, separated from one another by thousands of kilometres. Saint Helena has rugged cliffs and a greener mountainous interior, Ascension is younger and more arid, while the Tristan da Cunha archipelago is cool, windswept and dominated by steep volcanic terrain. Their exceptional isolation has produced distinctive ecosystems with many endemic plants and animals.
Overview
The territory is globally important for endemic landbirds and huge seabird colonies. Saint Helena holds the endemic Saint Helena Plover (Wirebird), while Ascension supports major colonies of Sooty Terns, frigatebirds, boobies and tropicbirds. Tristan da Cunha and its outlying islands are especially significant: Gough Island supports the endemic Gough Moorhen and Gough Bunting, while Inaccessible Island is home to the Inaccessible Island Rail, the world’s smallest flightless bird. The islands also breed several endemic or highly localized albatrosses and petrels. Access is a major challenge: Saint Helena has scheduled flights, but Tristan da Cunha is reached only by sea, and protected outlying islands such as Gough and Inaccessible have highly restricted access.
Top 10 target species
| Species | Annual frequency | January | February | March | April | May | June | July | August | September | October | November | December |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Atlantic White-Tern Gygis alba | 31.3% | 56.7% | 44.1% | 20.9% | 38.6% | 29.6% | 25.0% | 0.0% | 0.0% | 6.3% | 31.3% | 55.3% | 67.7% |
| Common Myna Acridotheres tristis | 25.4% | 80.7% | 31.8% | 10.9% | 17.1% | 25.2% | 0.0% | 0.0% | 25.0% | 12.5% | 13.6% | 32.6% | 54.9% |
| Common Waxbill Estrilda astrild | 22.3% | 61.1% | 25.4% | 7.1% | 13.0% | 21.7% | 50.0% | 0.0% | 25.1% | 6.3% | 7.3% | 10.0% | 40.8% |
| Masked Booby Sula dactylatra | 20.7% | 15.8% | 23.2% | 11.7% | 25.1% | 19.7% | 50.0% | 0.0% | 0.0% | 6.3% | 22.8% | 37.4% | 36.1% |
| Great Shearwater Ardenna gravis | 20.3% | 5.3% | 37.4% | 48.1% | 28.3% | 53.9% | 0.0% | 0.0% | 0.0% | 18.8% | 37.5% | 12.7% | 1.9% |
| Atlantic Yellow-nosed Albatross Thalassarche chlororhynchos | 18.9% | 7.0% | 32.5% | 49.8% | 26.4% | 2.1% | 25.0% | 0.0% | 0.0% | 25.0% | 41.7% | 15.0% | 1.9% |
| Yellow Canary Crithagra flaviventris | 17.7% | 49.2% | 27.8% | 7.9% | 12.5% | 9.2% | 25.0% | 0.0% | 0.0% | 6.3% | 8.6% | 20.6% | 45.8% |
| Soft-plumaged Petrel Pterodroma mollis | 16.8% | 5.3% | 27.7% | 39.7% | 24.2% | 17.5% | 25.0% | 0.0% | 0.0% | 12.5% | 37.5% | 10.8% | 1.9% |
| Brown Noddy Anous stolidus | 16.8% | 7.8% | 25.5% | 24.5% | 24.0% | 19.8% | 0.0% | 0.0% | 0.0% | 18.8% | 35.3% | 26.8% | 19.2% |
| Black Noddy Anous minutus | 16.2% | 4.4% | 16.8% | 8.4% | 20.5% | 12.7% | 25.0% | 0.0% | 0.0% | 0.0% | 26.3% | 47.6% | 33.0% |