Sulu and Tawi-tawi Fauna (Endemic Species)

This ecoregion includes the main islands of Jolo (Sulu) and Tawitawi and the surrounding smaller islands from Sibutu up to but not including Basilan Island. The climate of the ecoregion is tropical wet (National Geographic Society 1999). There are apparently short (two-week) dry seasons in January and May on Tawitawi (Allen 1998). Vegetation types in the Sulu Archipelago originally included beach forest, lowland rain forest, scrub forest, and mangroves. Unlike that of Palawan, which is located between Borneo and the Philippines, the Sulu Archipelago's fauna is not Sundaic (Allen 1998) and, though rather small, is poorly known biologically (L. Heaney, pers. comm., 2000). Palawan was the main pathway for immigrants from Borneo to the Philippines, and the Sulu have many taxa that are identical to or derived from taxa in Mindanao. Even Sibutu, close to Borneo and separated from the rest of the Sulu by the Sibutu Passage, contains an avifauna more closely related to the Sulu than to Borneo (Dickinson et al. 1991).

Although there are some Sulu birds with Sundaic distributions, the avifauna of the Archipelago is essentially Philippine (Dutson et al. 1992). The Sulu hornbill (Anthracoceros montani) is one example of an animal whose likely closest relative, the black hornbill (Anthracoceros malayanus), is from Borneo. There is a cline of relatedness to Borneo as one moves north among the islands. Sibutu contains birds of Bornean origin that are not found on Tawitawi (Allen 1998). The Sulus (Sangasanga, Bongao, Simunul, Tawitawi) also support a population of slow loris (Nycticebus coucang), a Sundaic primate that is not found in the remainder of the Philippines (Heaney 1986). There is one endemic mammal in the ecoregion . The Tawitawi Island rat (Rattus taitawiensis) is considered vulnerable (IUCN 2000) . Generally all of these emphasizes that the Sulu and Tawi-tawi island is a potential faunal region.

The ecoregion overlaps exactly with the Sulu Archipelago EBA. The EBA contains nine restricted-range birds, four of which are limited to the Sulus. All the restricted-range birds are forest species. Nine bird species qualify to near endemic to this ecoregion and four of these are endemic (Kennedy et al. 2000; table 2). Included in the ecoregion are the critically endangered Sulu bleeding-heart (Gallicolumba menagei), Tawitawi brown-dove (Phapitreron cinereiceps), and Sulu hornbill (Anthracoceros montani), and the endangered blue-winged racquet-tail (Prioniturus verticalis).

Sulu bleeding-heart (Gallicolumba menagei) 

Gallicolumba menagei is endemic to the Sulu archipelago in the Philippines. It is known by just two specimens taken on Tawi-tawi in 1891, when it was described as extremely rare. The only evidence of its continued existence derives from unconfirmed local reports in 1995. Local reports claim that it was quite abundant before the 1970s, but had declined dramatically and is now only rarely seen. Visits to Tawitawi in February and June 2009 did not produce any records of the species , and conversations with trappers and other local people have failed to find anyone familiar with the species (R. Hutchinson in litt. 2012).

Tawi-tawi brown-dove 
(Phapitreron cinereiceps) 

Phapitreron cinereiceps is endemic to the Sulu archipelago in the Philippines, where it is restricted to the island of Tawitawi and adjacent Sanga-sanga (Collar et al. 1999). On Tawitawi, there are recent records from four sites, including Languyan, Lubbuk and Tarawakan. On Sanga-sanga, it was recorded at one site in c.1987, but is almost certainly extinct there as the island retains virtually no forest. It was common at Tarawakan in 1996 and early 2008 (D. Allen in litt. 2008). The Tawitawi population is assumed to be very small, but the species is apparently shy and, as such, may not be as rare as feared.

Sulu hornbill (Anthracoceros montani)

This species is endemic to the islands in the Sulu archipelago in the Philippines. Described as common to abundant in the late 19th century, it has undergone drastic decline, and persists with certainty only on Tawi-tawi. Recent evidence suggests that its population is extremely low, perhaps numbering fewer than 20 pairs in the main mountain range. During a visit in February and June 2009, four individuals were reported in contiguous areas over two days on Tawi-tawi (I. Sarenas in litt. 2010). Local reports from 1995 suggested that it may visit the small islands of Tandubatu, Dundangan and Baliungan, and are unlikely to sustain resident populations. 

Blue-winged racket-tail (Prioniturus verticalis) 

The blue-winged racket-tail, palette des sulu, or lorito-momoto de las sulu (Prioniturus verticalis) is a species of parrot in the Psittaculidae family. It is endemic to Tawi-tawi island in the Philippines. Its natural habitats are subtropical or tropical moist lowland forests and subtropical or tropical mangrove forests. It is threatened by habitat loss.

Mantanani scops-owl
 (Otus mantananensis)

Mantanani scops-owl  is a species is listed as Near Threatened because there are some indications that its very small range is occupied by a moderately small, fragmented population which is undergoing a continuing decline owing to forest loss and degradation. However, little is currently known about the species's population size and structure, and the impact of threats, and its population is not regarded as severely fragmented or restricted to a few locations.

Yellowish bulbul (Ixos everetti)
Although this species may have a restricted range,  is not believed to approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). This species is evaluated as Least Concern.

Celestial monarch 
(Hypothymis coelestis)

This species, the Celestial monarch is declining rapidly as a consequence of widespread and continuing reductions in the extent and quality of lowland forest. This is causing severe fragmentation of its presumably small population, qualifying it as Vulnerable.

Grey Imperial pigeon

This species, Grey Imperial pigeon, occupies a very small range, currently occurring at perhaps fewer than ten locations. Its range, habitat and numbers are known or inferred to be in decline owing to the increasing conversion of natural forests to palm plantations. These factors qualify it as Vulnerable.

Several widespread but threatened species also occur on the islands, including the critically endangered Philippine cockatoo (Cacatua haematuropygia) and vulnerable rufous-lored kingfisher (Todirhamphus winchelli) (Collar et al. 1999; Stattersfield et al. 1998).

The critically endangered Philippine crocodile (Crocodylus mindorensis) was historically found on Jolo (as well as Luzon, Mindoro, Masbate, Samar, Negros, Busuanga, and Mindanao), but the only remaining populations are found on Mindoro, Negros, Mindanao, and Busuanga. The current wild population may be approximately 100 nonhatchlings (Ross 1998).

As of Sulu and Tawi-tawi's capability to hold large varieties of species, there is no question that the region is a potentially-able archipelago. Influenced by human activities and other factors, the Sulu and Tawi-tawi island species, either native or endemic are both in zenith of danger and threats.