Chance discovery in the Sulu Archipelago: Long lost cuckooshrike documented after nearly 20 years

In November 2025, the Sulu cuckooshrike (Coracina guillemardi) was documented again for the first time in almost two decades in the remote forests of Tawi-Tawi in the Sulu Archipelago in the southwest of the Philippines. The species was considered lost—not officially extinct, but without any confirmed records for years.

The discovery happened rather by chance. A team of staff from the Philippine Department of Environment as well as the conservation organization PhilBio had originally been searching for another particularly highly threatened species: the Sulu hornbill (Anthracoceros montani). This endemic hornbill species is among the rarest birds in the world; estimates suggest fewer than 20 breeding pairs remain. Habitat loss and hunting have pushed the species to the brink of extinction.

When the team heard the characteristic nasal calls of the Sulu hornbill early in the morning, the excitement was great. During the observations that followed, wildlife photographer Shareef Khaddafi Hairal photographed several birds in the tree canopy. Among them was an inconspicuous, gray bird that, despite its size, initially attracted no further attention.

Only later did it become clear how significant this observation was: after Hairal posted his photographs on social media, Philippine ornithologist Desmond Allen identified the gray bird as the Sulu cuckooshrike. Allen himself had last documented the species on Tawi-Tawi in 1998 and 2008—after that, all confirmed records were missing.

The Sulu cuckooshrike—a little-known species

The Sulu cuckooshrike is one of the most poorly documented bird species in Southeast Asia. It was scientifically described as early as 1886 by the Italian zoologist Tommaso Salvadori—at that time still under the name Graucalus guillemardi. The description was based on a single specimen from the island of Lapac in the Sulu Archipelago.

For many decades, the species was not recognized as distinct, but was instead treated as a subspecies of the bar-bellied cuckooshrike (Coracina striata). Only more recent taxonomic reassessments take differences in morphology and vocalizations into account and have treated the Sulu cuckooshrike as a distinct species again since 2024. In the IUCN Red List, however, it has still not yet been assessed separately, because the earlier classification as a subspecies remains the basis there.

Despite this long scientific history, astonishingly little is known about the bird. Even basic reference works such as Birds of the World still do not contain a separate illustration. Information on its distribution is also fragmentary: all modern, confirmed records come from the island of Tawi-Tawi. Whether the Sulu cuckooshrike also occurs on other islands in the archipelago or may already have disappeared there remains unclear.

The historical origin of the type specimen does suggest, however, that the species may once have been more widespread. Salvadori described it on the basis of a bird from Lapac, without strictly limiting its occurrence to a single island. The current data situation may therefore reflect not so much the actual distribution as the substantial knowledge gaps in this little-studied region.

Externally, the Sulu cuckooshrike remains inconspicuous, which has certainly contributed to it being overlooked for so long. It is a comparatively large cuckooshrike (Campephagidae) with almost uniformly gray plumage. Wings and tail can appear somewhat darker, while the eyes are strikingly pale gray. A darker facial mask extends from the bill across the lores to the forehead, but is usually only weakly pronounced. Unlike related species, it completely lacks the typical barring on the belly—an important feature that distinguishes it among Philippine cuckooshrikes.

Why it remained undocumented for so long

There are several reasons why the Sulu cuckooshrike went unrecorded for 18 years. For one thing, its range is probably very small: the species lives exclusively in the lowland and hill forests of the Sulu Archipelago. Many of these habitats are fragmented, difficult to access and have so far been insufficiently studied.

A decisive factor, however, is the political situation in the region. For decades, the Sulu Archipelago was shaped by instability and armed conflict. Groups such as Abu Sayyaf in particular made the region internationally known through kidnappings and acts of violence. Many countries issued travel warnings, and international research almost came to a complete standstill.

The consequences for science and conservation were severe: entire regions remained practically inaccessible for years—not for ecological reasons, but for security policy reasons. Even local conservation projects could only be carried out to a limited extent, and systematic biodiversity surveys hardly took place at all.

Only in recent years has the security situation in parts of the archipelago cautiously stabilized. Through coordinated measures by authorities and the military, it is now at least possible again for local researchers to enter and investigate remote areas. This development contributed decisively to making it possible to track down species such as the Sulu cuckooshrike again in the first place.

The rediscovery shows that lost does not necessarily mean rare or even extinct. In many cases, it simply means that for a long time no one could search for a species—or was allowed to. Initial recent observations even suggest that the Sulu cuckooshrike is possibly not extremely rare in suitable habitats. In 2026 alone, the species was reported several times in eBird checklists from Tawi-Tawi.

Hope for more Lost Birds

Other bird species in the Sulu Archipelago are also considered lost, including the Sulu jungle flycatcher (Cyornis ocularis), last documented in 1998, and the Sulu bleeding-heart (Gallicolumba menagei). This critically endangered species is known only from two specimens collected on Tawi-Tawi in 1891. Despite targeted searches in the 1990s, it has remained undetected ever since.

The fact that the Sulu cuckooshrike has now been documented again gives reason to hope that these two endemic species might also still exist.

Habitat loss as the greatest threat

Even though the Sulu cuckooshrike has recently been documented, it is very likely to be threatened. Nearly all bird species found exclusively in the Sulu Archipelago are under pressure—and much suggests that this also applies to Coracina guillemardi.

The greatest threat is the ongoing loss of its habitat. The forests of the archipelago are increasingly being logged or converted into agricultural land. Added to this are mining activities, which represent further encroachment into areas that have so far remained largely undisturbed. For species with an extremely small range, the loss of individual forest patches alone can have devastating consequences.

This development is part of a nationwide trend: in the Philippines, deforestation has been one of the central environmental problems for decades. Over the course of the 20th century, the share of forest cover fell from about 70% to around 20%. The ecological consequences range from biodiversity loss and soil erosion to flooding and long-term losses in agricultural productivity.

At the same time, there is still hope. Parts of the island of Tawi-Tawi still contain comparatively well-preserved forest areas that could serve as the last refuges for many endemic species. But as conservationists emphasize, the window of time is limited: land degradation and climate change could place additional pressure on the already fragile island ecosystems.

With the renewed record of the Sulu cuckooshrike, another species can be removed from the list of the initiative Search for Lost Birds. Bird species are considered lost there if they have not been clearly documented for at least ten years—for example through photographs, sound recordings or genetic data. The rediscovery of such species is not an isolated case. As recently as 2025, several rediscoveries were made, including the Bismarck kingfisher in the Bismarck Archipelago of Papua New Guinea as well as the cinnamon-chested blue flycatcher on the Philippine island of Luzon.

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Source

• Foster, N. (2026, 15 March). Found: Sulu Cuckooshrike photographed in Tawi-Tawi after 18 years. Search for Lost Birds. https://searchforlostbirds.org/news/found-sulu-cuckooshrike-photographed-in-tawi-tawi-after-18-years