Current view: Text account
Site description (2001 baseline):
Site location and context
The site covers the south-western part of the island, south of a line linking Powell Point and ‘The Buoys’ in the south-east and Horse Pasture Point in the north-west, via Clifford Arboretum in the interior, together with Egg Island (79 m), Speery Island (120 m) and all other offshore islets, stacks and rocks. All four vegetation zones on the island are represented. Below 350 m, c.25% of the area, the landscape is arid with large-scale erosion, dominated by
Suaeda,
Lantana and
Carpobrotus. This gives way to pasture and non-indigenous woodland, up to 500 m, dominated by
Pennisetum,
Cynodon and
Digitaria, with
Acacia and
Pinus. Above 500 m lies ‘moist’ and ‘semi-moist’ grassland, woodland (dominants include
Agrostis,
Pennisetum and
Stenotaphrum, with
Podocarpus,
Acacia and
Pinus) and flax
Phormium tenax plantations. At High Peak is a small remnant native thicket of endemic
Dicksonia ferns and
Melanodendron cabbage trees. The coast is dominated by imposing sea cliffs, rising mainly to between 300 m and 570 m. High Peak (798 m), in the far north-east, is the highest point. Egg Island, off the north-west lee side, is a mass of pale bedded lavas with an apparent dip towards the south-west, while nearby Peaked Island (32 m) is a sharp pyramid of scoriaceous slag. Speery Island is a spectacular steep-sided, jointed monolithic pipe of paler alkaline trachyte, whilst neighbouring Salt Rock (40 m) is a remnant of a wide basaltic dyke. The remaining islets and stacks are basaltic. Vegetation (shrubs, grasses, weeds) has been noted only on Lighter Rock, Ladies Chair, Egg Island, Peaked Island and Thompson’s Valley Island, all in the lee. Lichens have been found at the summit of Egg Island. The heaviest guano deposits are on Egg, Peaked and Speery Islands. In the south, the Speery Island group of outliers is much more exposed and, but for Speery Island itself, has not been visited by ornithologists and may therefore harbour unrecorded seabirds. Included in the IBA are three important breeding sites for
Charadrius sanctaehelenae, i.e. at Broad Bottom, Southern Pastures and Man and Horse. There is an important fossil site at Sandy Bay.
See Box and Table 2 for key species. Although as many as 45 bird taxa have been recorded, there are now only seven known species of breeding seabirds and 11 species of resident landbirds, i.e.
Oceanodroma castro,
Phaethon aethereus,
Sula dactylatra,
Alectoris chukar,
Phasianus colchicus,
Gallinula chloropus,
Charadrius sanctaehelenae,
Sterna fuscata,
Anous stolidus,
A. minutus,
Gygis alba,
Columba livia,
Geopelia striata,
Acridotheres tristis,
Foudia madagascariensis,
Padda oryzivora,
Estrilda astrild and
Serinus flaviventris.
Sula leucogaster may also breed. Speery Island has the highest seabird breeding diversity in the IBA with, probably, seven species. There are also records of non-breeding visitors and vagrants with fewer than five records. The former include
Diomedea exulans,
Pterodroma mollis,
Oceanites oceanicus,
Fregetta grallaria,
Fregata sp.,
Ardea cinerea,
Bubulcus ibis,
Ciconia ciconia,
Calidris alba,
Stercorarius parasiticus,
S. pomarinus and
Sterna paradisaea. The site requires further study.
Non-bird biodiversity: As with North-east St Helena (SH003), the endemic invertebrates are of particular importance.
Pressure/threats to key biodiversity
The site includes three Nature Reserves. The Norman Williams Nature Reserve (Horse Ridge, 7.2 ha) was proclaimed in 1982. The Old Joan Point National Forest (south-west coast, 560 ha), proclaimed in 1994, is an area of steep cliffs that supports remnant populations of endemic and indigenous plants. The High Peak–Peak Dale Forest Reserve (in the south, 6.4 ha), proclaimed in 1995, includes not only the native tree-fern thicket, but also the largest remaining population of Gumwoods. Strict protection of all bird species, with the possible exception of
Acridotheres tristis, is provided for under the St Helena Birds Protection Ordinance of 1996. Species regarded as ‘game’, i.e.
Alectoris chukar and
Phasianus colchicus, are subject to the appropriate game laws. With the fall in numbers of
Charadrius sanctaehelenae further conservation measures are needed. Seabird eggs and guano continue to be taken at intervals from the stacks off the lee side, north-western coast, by fishermen.
Recommended citation
BirdLife International (2024) Important Bird Area factsheet: South-west St Helena (St Helena (to UK)). Downloaded from
https://datazone.birdlife.org/site/factsheet/south-west-st-helena-iba-st-helena-(to-uk) on 29/12/2024.
