São Tomé is a volcanic island situated in the Gulf of Guinea, off the west coast of Africa, in the middle of a chain of islands which includes Bioko (part of EBA 086), Príncipe (EBA 083, with which it forms the twin-island nation of São Tomé e Príncipe) and Annobón (EBA 081).

The original vegetation included lowland rain forest to c.800 m, with montane forest extending from 800 to 1,400 m, and mossy forest above. Dry forest occurs in the north of the island, but has largely been replaced by savanna and open cultivation.

All the restricted-range species occur in forest and-although a number have adapted to plantations where large shade-trees are retained-several species are primary-forest specialists and four apparently occur only in the lowlands (Bostrychia bocagei, Lanius newtoni, Amaurocichla bocagii, Neospiza concolor, all rediscovered in 1990 and 1991). Further detailed accounts on individual species can be found in Jones and Tye (1988) and Atkinson et al. (1991, 1994a).

São Tomé's distinctive avifauna includes two endemic monospecific genera, Amaurocichla and Neospiza, as well as two remarkable 'giants', Nectarinia thomensis (formerly placed in the monospecific genus Dreptes) and Ploceus grandis, and a remarkable 'dwarf', Bostrychia bocagei. Sibley and Monroe's (1990, 1993) taxonomic review elevated several São Tomé taxa to specific status, including Alcedo thomensis, although the status of this species remains uncertain (Peet and Atkinson 1994).

The lowlands of São Tomé are almost entirely cultivated and primary forest remains only in the south-west and centre of the island, largely at higher altitudes. However, since independence in 1975 many plantations have reverted to secondary growth, and habitat conditions for birds are thus probably as favourable as they have been for a long time.

A forest survey in 1989 found total forest cover to be c.90%; of this, 28% was primary forest, 30% secondary forest and 32% shade forest. All endemic species remain threatened to some degree by forest loss from the likely expansion of agriculture, possible revitalization of plantations, and the increasing consumption of timber for domestic cooking and construction, but also for drying cocoa, for which the demand is likely to rise sharply if the cocoa market expands (N. B. Peet and P. W. Atkinson in litt. 1993).

If the four lowland forest species are indeed restricted to altitudes below 500 m, then only the forest in the Xufexufe and Ana Chaves valleys will be of sufficient area to support viable populations, though even these would be precariously small and thus highly vulnerable to development. However, there are considerable areas of primary forest between 500 and 1,000 m in the centre of the island which have not been visited by ornithologists and which may harbour these species (Peet and Atkinson 1994). These birds may, however, also be under pressure from alien mammals (e.g. black rat Rattus rattus, mona monkey Cercopithecus mona, African civet Civettictis civetta and weasel Mustela nivalis), which, coupled with possible further forest clearance, could lead to species extinctions (Dutton 1994).

Collar and Stuart (1988) ranked the forests in south-west and central São Tomé second in a list of 75 of the most important forests for conservation of threatened birds in tropical Africa. These forests were proposed for protection by Jones et al. (1991) and were gazetted in 1993 (Jones 1994a).

Recommended citation
BirdLife International (2024) Endemic Bird Area factsheet: São Tomé. Downloaded from https://datazone.birdlife.org/eba/factsheet/84 on 23/11/2024.