The 400 or so islands of the Sulu archipelago stretch south-west from the southern Philippine island of Mindanao to Borneo. The EBA covers the main islands of Sulu (or Jolo), Tawitawi and Sibutu, and many smaller offshore islands. Basilan, north-east of the archipelago, is included with Mindanao (EBA 154). The Sulu islands were once covered in forest, including lowland rain forest, beach forest, scrub forest and mangroves, but today much native habitat has been replaced by cultivation.

All the EBA's restricted-range species are forest birds, and, although their patterns of distribution between the islands vary, almost every species occurs on Tawitawi.

Of several subspecies endemic to the EBA, Sulu Woodpecker Dendrocopos (maculatus) ramsayi is most distinctive and a candidate for elevation to species rank, and Sulu Hanging-parrot Loriculus (philippensis) bonapartei is also a possible split. Sulu Hawk-owl Ninox philippensis reyi, apart from being clearly distinct from N. philippensis, almost certainly represents the nominate form of a species which occurs on other small islands (see under Mindoro, EBA 150) (N. J. Collar verbally 1997).

In 1991 observations made from the air indicated that virtually no forest remained on Sulu, and that on Tawitawi only the eastern part of the island supported any substantial tracts (Lambert 1993a). In 1994 primary forest on Tawitawi was being rapidly cleared, although there were still large areas of very degraded forest, mostly recently logged (T. M. Brooks and G. C. L. Dutson in litt. 1994). In 1996 there were plans to replace some of the most extensive areas of the remaining forest with oil-palm plantations. The smaller islands of Sibutu and Simunul have both been largely cleared and although forest is regenerating, the islands are dry and coralline and it will take a long time before the habitat becomes again of value to forest-dependent species, which, in the meantime, may be lost (D. Allen in litt. 1996).

Loss of habitat is thus the main threat to the birds of this EBA, and further losses associated with the economic development of Tawitawi in particular need careful monitoring (D. Allen verbally 1997).

Not surprisingly, all the endemics are considered highly threatened, especially Gallicolumba menagei and Anthracoceros montani, which have few recent records from the main islands. However, both these species are reported by local people from three small islands in the Tandubas group which still have small tracts (10 km ²) of lowland forest and which may therefore be very important for their survival. Small-scale logging does take place on these islands and, although at a slow pace, will have a great impact on the already low density of the reported populations (Diesmos and Pedregosa 1995). It is clear that more fieldwork is necessary to establish the nature of remaining habitat on islands in this important EBA.

Other widespread threatened species which occur in the EBA include Blue-naped Parrot Tanygnathus lucionensis (Endangered), Rufous-lored Kingfisher Todirhamphus winchelli (Endangered; Tawitawi may be a stronghold) and Black-bibbed Cicadabird Coracina mindanensis (Vulnerable). The Sulu archipelago is also considered a stronghold for the Philippine Cockatoo Cacatua haematuropygia (Critical; once found throughout the Philippines); several hundred still survive on Tawitawi but the species is declining as a result of illegal logging and shooting (Lambert 1992).

Recommended citation
BirdLife International (2024) Endemic Bird Area factsheet: Sulu archipelago. Downloaded from https://datazone.birdlife.org/eba/factsheet/156 on 22/11/2024.