Bird Species New to Science from Southeast Asia (1997 – 2007)
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Bird species new to science from Southeast Asia (1997 – 2007) Yong Ding Li A Brief Overview Southeast Asia is one of Earth’s least studied, yet among its richest and most diverse region in terms of total biodiversity and species endemism. Virtually all of political Southeast Asia within the Oriental zoogeographic region, excluding Indonesia’s West Papua overlaps into four of Earth’s 34 known biodiversity hotspot units, namely Sundaland, Wallacea, Philippines and Indo-Burma. (Above) Large expanses of montane evergreen forests in central Sundaland, of which Singapore Sulawesi might harbor undescribed bird species. (Yong Ding Li) forms a part of together with Sumatra, Borneo, Java and Peninsular Malaysia, on is own is already incredibly speciose, with an estimated vascular plant diversity of about 25 000 species. The estimated bird diversity of all Southeast Asia runs into over 1500 species, with a large proportion endemic. Indonesia by her own already has over 400 species of endemic birds, approximately a quarter of her known avifauna and the highest absolute bird endemism in the world. Each year, perhaps each month would be more apt, sees the discovery of a few new species of organisms, often an obscure beetle, fly, crab or some arthropod species but also an occasional vertebrate. As far as larger vertebrates are concerned, new species to science are far and few, but are often exciting and captures more media attention than their smaller ‘bug’ counterparts. Take for example the media hype that was generated by the recent discovery of the Giant Peccary in South America, versus the tens of dozens of new flies species described from Singapore! In the last ten or so years, 16 bird species new to science in our region have been described, averaging about one to two birds species per year as biologists continue to scour all but the remotest regions in Southeast Asia. Excluded here in this treatment are Cream-bellied Munia Lonchura pallidiventer and Pygmy Frogmouth Batrachostomus pygmaeus, both invalid due to poorly supported taxonomic evidence. Among the tropics in general, this puts our region way ahead of all Africa south of the Sahara and Australasia (including Pacific Islands), but still far behind South America which undoubtedly boasts Earth’s richest avifauna. In comparison early 20 staggering distinct new bird species were described in South America alone from 2002 to 2007, including a Page 1 of 18 number of tyrant-flycatchers, antbirds, tapaculos, woodcreepers and parrots. This of course excludes the numerous taxonomic splits of known, pre-existing geographical races that is also taking the region by storm as evidenced by the large number of published journal papers in this area. Classic cases of taxonomic splits in Southeast Asia as a result of elevating status of former races into full species are those of the Leafbird Chloropsis, Hodgson’s Hawk Cuckoo and Brown Hawk-Owl complexes. Within Oriental Asia as a whole, Southeast Asia clearly leads in terms of new birds described, the only exceptions in recent years being the gaudy Bugun Liocichla and Nicobar Scops Owl from India, Serendib Scops Owl from Sri Lanka, the Sichuan Treecreeper of central China and Taiwan Bush-Warbler from its namesake island. Among the Southeast Asian nations, Indonesia at present dominates the list with a total of seven new species discovered, the majority being nocturnal birds like Owls and Nightjars. This should not surprise as the vast and rugged Indonesian archipelago abound with islands, many of which has never been visited or extensively studied at all. In general a disparate proportion of the new discoveries tend towards nocturnal birds, reflecting a clear biasness of scientific work to the more accessible taxa and perhaps the generally diurnal habits of field (Above) Calayan Rail (Carmela Española) workers. In a way this is more or less expected since comparatively less research and field work is conducted after dusk. In comparison, all of the recent, mainland Southeast Asian avian discoveries were of passerines, mostly babblers, as ornithologists penetrate into some of the poorly known mountain regions inland. Vietnam, ironically one of Southeast Asia’s most densely populated (253 people/km²) and agriculture intensive nations surprised many by its three new distinct species of babblers, namely two laughing- thrushes and a barwing from her central mountainous regions that have formerly seen little or no survey efforts. Sharing the insular geographical characteristics of Indonesia and a massive human population, it was also a pleasant surprise to uncover four new species from the Philippines, a rail, a woodcock, a parrot and a sunbird. Much of what forest that remains in the Philippines, including in national parks are all under pressure from the demands of development, harvesting and a booming population. Couple this with a hitherto sparse scattering of biological fieldwork and one understands why it has one of the most threatened, yet poorly known avifauna. Indonesia – Wallacea Before the definitive field guide, Coates and Bishops’ Birds of Wallacea was published ten years ago, there was hardly any comprehensive reference work on the birdlife of this vast region except for various annotated checklists and a handful of scattered birdwatcher reports. Indeed, Wallacea, as defined by its thousands of islands including Sulawesi, the lesser Sundas and the Moluccan islands is indeed still among the biologically least known Page 2 of 18 regions on the planet. Many of the outer, small Wallacean islands like Damar and Tanahjampea were visited only a handful of times, while some not even more than once by ornithologists in recent history, hampered largely by difficulty of access. Levels of research and biological explorations in Wallacea as a whole is pathetically meager when compared to the amount of work that was and still is done in say Java or Malaya. It thus does not come as a surprise that a bird species, shortly after its discovery or description, vanishes into obscurity and ‘extinction’ until another intrepid ornithologists decides to visit. The biggest landmass in Wallacea, Sulawesi is also perhaps the most biologically interesting, made so by its high species diversity and endemism, as well as its unusual combination of curious taxa like Cuscus, Anoa, Maleo, a testimony to its complex geological past. Much of Sulawesi and its satellite islands, until recently was covered in tall evergreen forest though the advent of commercial and illegal logging has since changed the situation drastically. A number of forested island groups (many now seriously deforested) fan out from each of Sulawesi’s four major peninsulas, including Taliabu, Togian, and Sangihe islands. Some of these remote satellite islands that cluster around Sulawesi’s rugged peninsulas, not more than a decade ago, saw the discovery and description of two owls and two rail species new to science. One of these, the Talaud Islands is a group of islands off Sulawesi’s northern Minahassa peninsula. The Talaud islands were seldom visited due to their isolation from the Sulawesi mainland. Visiting ornithologist Frank Lambert was fortunate to have serendipitously uncovered two species of rails within a period of two years while working on the islands in the late 1990s. MAP 1. The geographic positions of various satellite islands of Sulawesi in relation to the Sulawesi mainland and insular Southeast Asia. The three group of islands where new bird species have been described are each highlighted in bold here, namely the Talaud Islands (Talaud Rail, Talaud Bush-Hen), Sangihe (Sangihe Scops Owl) and the Togian Islands (Togian Hawk- Owl) The main island of Karakelong in the Talaud islands group, together with neighbouring Sangihe are small groups of volcanic islands halfway between the Sulawesi and Page 3 of 18 Mindanao mainland, sitting isolated in the Celebes Sea. During a trip there on 15th August 1996, Lambert was to first observe an unfamiliar rail by the roadside from the vehicle he was traveling on. This bird, unfamiliar, yet distinctive was at then observed walking casually across the tarmac road, later moving into damp grasslands in a rural area. Enquiries with local villagers found that the bird, known as the ‘tu-a’ was actually not unfamiliar to them. In fact tu-a was even occasionally taken for the cooking pot. Sooner or later, the first specimen of the ‘Tu-a’ now christened the Talaud Rail Gymnocrex talaudensis was procured for western science when a live specimen was purchased from a local bird seller the following month. On the same year, a second unknown rail, this time a forest-dwelling bush-hen of the genus Amaurornis (similar to our White-breasted Waterhen) was also initially casually sighted, again by Lambert. Further searches eventually lead to this enigmatic species, the Talaud Bush-Hen Amaurornis magnirostris and the other new rail from Talaud to be described for science in late 1998. Sangihe island, a hundred over kilometers southeast of Karakelong in Talaud, held an unknown scops owl species inhabiting its forested volcanic slopes. In reality, specimens of Sangihe’s unknown scops owl was already long known and procured in Dutch and German collections, though never officially identified and described. Long before its formal discovery, specimens of this little owl had been separately procured by ornithologists A.B. Meyer, C, Platen and C.P Hoedt. Platen himself took the type (A specimen(s) designated for the formal taxonomic description of a species) specimen from Sangihe in 1887, then called Sangir. Unfortunately one of the early specimens was presumably lost during the war, the only clue to its existence being historical records. A ‘modern’ specimen of the owl was finally obtained back in 1985 by F. Rozendaal from coconut plantations and secondary forests on Sangihe. So, while existing specimens of this bird had been sitting idle in museums for over a century, it was only in the last years of the 1990s that with vocalization analysis, combined with a robust study of the existing specimens by Frank Lambert and Pamela Rasmussen, the latter a bird taxonomist, revealed these scops owls to be the hitherto undescribed Otus collari.