Nakai-Nam Theun: can development save one of South-East Asia's last wildernesses?

by Joe Tobias, Pete Davidson and William Robichaud, from OBC Bulletin 28, November 1998.

Nam Theun 2, a major hydropower development proposal, has focused attention on an important protected area which might hold the key to conserving some of the rarest and most highly threatened species of birds and mammals in South-East Asia. This article summarises the significance of Nakai-Nam Theun National Biodiversity Conservation Area in central Laos, sketches recent developments in the hydropower project, and looks to the future.

Laos is a land-locked country separated from Vietnam by the Annamite mountains, an isolated range that is covered in several areas by huge tracts of relatively undisturbed montane evergreen forest. The largest of these, one of the most pristine wildernesses remaining in South-East Asia, is largely encompassed within Nakai-Nam Theun National Biodiversity Conservation Area (NBCA). A series of surveys conducted since 1994 by the co-operative programme of the Wildlife Conservation Society (WCS), the Centre for Protected Areas and Watershed Management (CPAWM) of the Lao Department of Forestry, and the World Conservation Union (IUCN) have revealed that the area has an extremely high biodiversity conservation value. Plans to develop a $2 billion hydropower project along the major river draining the area (the Nam Theun) have generated considerable controversy and promoted intensive research into the likely effects of such a development. Some of this research has been directed towards identifying appropriate mitigation for the damage that will inevitably be caused to the environment if a dam is built.

Nakai-Nam Theun covers approximately 3,445 km2 of the Annamite mountains and the adjacent Nakai Plateau in the provinces of Khammouane and Bolikhamxay. A proposed northern extension along the Vietnam border in Bolikhamxay would link Nakai-Nam Theun to the Nam Chouan proposed NBCA, and a minor southern extension would make the area contiguous with Hin Namno NBCA, a bizarre karst landscape of limestone hills and one of the most important sites for primate conservation in Indochina (1). A third proposed corridor would annex the Khammouane Limestone NBCA to the west. These potential additions expand the size of the protected area to nearly 5,000 km2, encompassing altitudes between 400 m and 2,700 m and a broad variety of habitats and species assemblages (2). The potential result is a composite of seven protected areas bridging an international border: in Vietnam, Pu Mat, Vu Quang and Phong Nha reserves, and in Laos, Nam Chouan, Hin Namno and Khammouane Limestone NBCA's, with the hub of these being Nakai-Nam Theun. If managed wisely and effectively, this ësuper-reserve' would rank amongst the most important sites for biological and cultural conservation in the world (2).

Red-tailed Minla © Joe Tobias

Red-tailed Minla © Joe Tobias

The area is described in detail by Evans and Timmins (3) and IUCN (2). Semi-evergreen forest, deciduous dipterocarp forest and stands of pine are all found on the Nakai Plateau (now heavily deforested by salvage logging prior to the planned inundation of the c. 450 km2 reservoir area) and in the Annamite foothills to the east, grading into more exclusively evergreen forests as the land rises towards the Vietnamese border. Higher still, huge areas of montane fagaceous forest cloak the slopes, interspersed with patches of Fokienia hodginsii, a commercially valuable cypress-like conifer. On mountain-tops and above c. 2,000 m the fagaceous forest gives way to more stunted, rhododendron-dominated ericaceous cloudforest. A unique feature of Nakai-Nam Theun's proposed northern extension is the 'everwet' forests, found in narrow bands where low-elevation saddles (500-800 m) in the mountain chain enable the Vietnamese north-east monsoon to penetrate across the border, a phenomenon otherwise impeded by higher stretches of the Annamites.

Blyth's Kingfisher © Joe Tobias

Blyth's Kingfisher © Joe Tobias

A total of 405 bird species has been conclusively identified in Nakai-Nam Theun and the adjacent northern extension during a few months fieldwork.3,4,5 The final total, if provisional field records can be confirmed, will probably exceed 430 species. This is by far the highest avian species richness of any site yet surveyed in Laos and is the highest recorded in a single protected area in South-East Asia despite the relatively brief fieldwork conducted (as comparisons: 318 spp. recorded at Khao Yai National Park and 382 spp. recorded at Doi Inthanon National Park, Thailand; 330 spp. recorded at Bach Ma National Park and 270 spp. recorded at Cat Tien National Park, Vietnam). Of particular importance are no less than 11 Threatened and 27 Near-threatened bird species (Collar et al.(6) Appendix 1 lists these species, several of which are not reported by Evans and Timmins (3)).

The key to this richness is the topographical and botanical variability already described. Slow-flowing rivers and adjacent forest on the Nakai Plateau provide habitat for scarce species such as White-winged Duck (7) Cairina scutulata, Lesser Fish-eagle Ichthyophaga humilis, Pied Falconet Microhierax melanoleucos and River Lapwing (8) Vanellus duvaucelii. Mid-altitude river systems are home to Blyth's Kingfisher Alcedo hercules and Tawny Fish Owl Ketupa flavipes. Lowland/foothill semi-evergreen forest supports populations of many Indochinese specialities including Red-collared Woodpecker Picus rabieri, Pale-headed Woodpecker Gecinulus grantia, Indochinese Green Magpie Cissa hypoleuca, White-winged Magpie Urocissa whiteheadi and Rufous-throated Fulvetta Alcippe rufogularis. The vast expanse of evergreen fagaceous forest provides habitat for Coral-billed Ground Cuckoo Carpococcyx renauldi, Green Cochoa Cochoa viridis, Red-tailed Laughingthrush Garrulax milnei and Rufous-necked Hornbill Aceros nipalensis amongst many others.

The Beautiful Nuthatch Sitta formosa is usually found on the boughs of Fokienia hodginsii, while Spectacled Fulvetta Alcippe ruficapilla, Whiskered Yuhina Yuhina flavicollis and Chestnut-tailed Minla Minla strigula are confined to cloud and elfin forest close to the summits of the highest peaks. The 'everwet' forests of the proposed northern extension are a stronghold of Short-tailed Scimitar-babbler Jabouilleia danjoui and Crested Argus Rheinardia ocellata, with many individuals of the latter species calling from arenas on ridge-tops, often close to new logging roads but always difficult to catch sight of, no matter how cautiously they are approached. Spotted Wren Babbler Spelaeornis formosus occurs in forested valleys and Jerdon's Bushchat Saxicola jerdoni breeds locally in riverine scrub and stands of Imperata grassland.

Coral-billed Scimitar-babbler © Joe Tobias

Coral-billed Scimitar-babbler © Joe Tobias

Nakai-Nam Theun is perhaps most significant for the important populations of threatened mammals it supports. Asian Elephant Elephas maximus and Gaur Bos gaurus survive in the area. Approximately nine primate species occur, including three that are Globally Threatened or Data Deficient (9): Pygmy Loris Nycticebus pygmaeus (provisionally identified, pending research into Nycticebus taxonomy in South-East Asia), Douc Langur Pygathrix nemaeus (the most important population of the red-shanked form in the world (10)) and an as yet unidentified pale-cheeked gibbon of the Nomascus subgenus, probably of the form leucogenys or siki (again, taxonomic relationships in this group remain unclear: Thomas Geissmann in litt. 1998). Along just one stretch of incompleted road above the village of Ban Navang, 15 species of carnivore have been recorded, including many rare cats such as Asiatic Golden Cat Catopuma temmincki, Marbled Cat Pardofelis marmorata, Clouded Leopard Pardofelis nebulosa and Tiger Panthera tigris (11). On the basis of current, admittedly patchy, knowledge, the NBCA emerged as the second most important area in the world outside Madagascar for the conservation of small carnivores (12).

Most remarkably, several new mammal species have recently been described from the area. The most distinct of these discoveries is the Saola Pseudoryx nghetinhensis (13,14). To date, this extraordinary long-horned bovid has evaded biologists in the wild but several have been captured or killed by villagers in Nakai-Nam Theun and the proposed northern extension (15,16). It is known only from the central Annamites of Laos and Vietnam, and Nakai-Nam Theun possibly contains the most viable population of the species in a legally protected area (5). Another newly described large mammal, the Giant Muntjac Megamuntiacus vuquangensis (18), occupies a restricted world range centred around this region (17,18,19). A small dark muntjac, possibly the recently described Muntiacus truongsonensis (20), also occurs in less disturbed tracts of montane evergreen forest in the area. Furthermore, a distinctive forest rabbit found in the area (probably Nesolagus sp.) awaits formal description (R.J. Timmins in litt. 1997), and the Indochinese Warty Pig Sus bucculentus was recently rediscovered in the area (21) after being considered extinct (22). These findings have focused much popular attention on the region, (23,24,25,26) showing it to be inadequately studied but confirming its status as a critical area for conservation. In conclusion, it cannot be stressed emphatically enough that the species richness and conservation importance of the mammal community at Nakai-Nam Theun is truly exceptional, surpassing almost all other protected areas in South-East Asia.

Conservation and the future
If adequately protected, Nakai-Nam Theun will support vital populations of many rare species that are threatened with extinction both regionally and globally. Alongside an outstanding biological heritage, the reserve contains a remarkable diversity of ethno-linguistic groups, some of whom face imminent extinction themselves (2). Whether the Nam Theun 2 hydropower project goes ahead or not, long-term protection of the area requires urgent and concerted effort. The site should form an integral component of a conservation strategy for the Annamite chain as a whole, especially as it could, and should, create a link between several disparate protected areas. Legal protection of the proposed corridor areas and recognition of Nakai-Nam Theun as a world heritage site under the UNESCO World Heritage Convention (2) would be appropriate and richly deserved steps in the right direction (2,5,15).

The Nam Theun 2 project has stimulated and financed a series of important ecological studies in Nakai-Nam Theun NBCA since 1995, resulting in our current knowledge and a comprehensive management plan for the area (2). It also proposes to fund local conservation action for several decades with a portion of profits accrued through the sale of electricity. However, the optimistic implications of this potential funding are counterbalanced by the absence of any precedent amongst hundreds of comparable development projects around the world: despite frequent promises to the contrary, it is difficult to cite a single example of hydropower development positively influencing biodiversity conservation. In essence, Nam Theun 2 will destroy one recently outstanding area and facilitate access to another. The resultant degradation is likely to be painfully predictable, no matter how many millions of dollars are poured into preventing it. The major difficulty facing conservationists in Laos is not money. As Berkmüller et al.(27) state, 'low skill levels, limited motivation and insufficient institutional capacity pose greater constraints to management implementation than funding'. Nevertheless, given the 'dam scenario' an opportunity presents itself, however elusively, for development and conservation to work in tandem for the benefit of the Lao people and their environment. Whether this opportunity is grasped, or whether the profits are enjoyed exclusively in the corporate and political sectors, remains to be seen.

Recently, another twist has developed in the tale: the Asian economic crisis has undermined the financial security of the hydropower project. In particular, doubts have been raised regarding the ability of Thailand, theoretically the sole recipient of Nam Theun 2's power, to afford the electricity generated by the dam. This has resulted in further delays while the World Bank deliberates over its approval of the project. While this uncertainty continues, the prospects for sustained conservation in Nakai-Nam Theun are clouded. This is partly because the project has unwittingly discouraged bilateral conservation donors and delayed the 'no dam scenario' conservation process. Meanwhile, an eight-month phase of further surveys and management activities commenced in May 1998, conducted under the auspices of the Lao government, the World Bank, IUCN and WCS, with the aim of initiating some of the measures recommended in the 1997 management plan.

Hydropower development aside, pressures imposed by logging interests, road development, very high human population growth and intense hunting also loom menacingly over the future of Nakai-Nam Theun and its inhabitants (2,15). Another particularly damaging and intractable problem is the incursion of Vietnamese poachers and wildlife salesmen across the remote international border (2,5,28). Their principal intention is to harvest or purchase species used in traditional medicine, a trade which is stripping the border area (and indeed much of South-East Asia) of turtles and pangolins, and rapidly reducing populations of many other species of global conservation importance such as Crested Argus and Douc Langur. Recently, the Vietnamese and Lao governments have taken commendable steps to solve this problem by convening jointly to discuss biodiversity conservation issues along the shared border (28), but as yet there has been insufficient direct action to prevent poaching and trading of wildlife. To be successful, a conservation strategy for the area must effectively address each of these problems in turn.

As Laos gradually opens its borders, the prospect of birders visiting the country improves. In fact, there has been some discussion of developing Nakai-Nam Theun as a destination for 'eco-tourists' (2). Any naturalist overcoming the troublesome logictics of visiting this wonderful and unique area will be handsomely rewarded – that is, of course, if the magnificent forests of the watershed can be preserved.

Our field surveys would not have been possible without the cooperation of CPAWM and its staff (especially Chantaviphone Inthavong, Venevongphet, Xanxai Souliyakane, Sivannavong Sawathvong and Boonhom Sounthala), the Science, Technology and Environment Organisation (STENO) of the Lao Prime Minister's Office (especially Noulin Sinbandith and Madame Monemany Nhoybouakong) and IUCN, especially the Lao country representative, Stuart Chape. Locally, we have received generous assistance from the Provincial Agriculture and Forestry Offices of Khammouane and Bolikhamxay Provinces. Many others made valuable contributions to fieldwork, report writing, early drafts of this manuscript and our dubious sanity in general, especially Will Duckworth, Tom Evans, Jim Jarvie, Khamkhoun Khounboline, Sinaun Phommachak, Khounmee Salivong, Rob Timmins, Robert Tizard, Chantavi Vongkhamheng and Dick Watling.


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Appendix: Birds of conservation significance recorded in the Nakai-Nam Theun area (threat categories according to Collar (6) taxonomy and nomenclature following Inskipp, et al.(29))

Threatened species; Greater Spotted Eagle, Aquila clanga; Siamese Fireback, Lophura diardi; White-winged Duck, Cairina scutulata; Crested Argus, Rheinardia ocellata; Wood Snipe, Gallinago nemoricola; Blyth's Kingfisher, Alcedo hercules; Rufous-necked Hornbill, Aceros nipalensis; Red-collared Woodpecker Picus rabieri; Grey-sided Thrush, Turdus feae; Short-tailed Scimitar Babbler, Jabouilleia danjoui; Beautiful Nuthatch, Sitta formosa; Near-threatened species; Von Schrenk's Bittern, Ixobrychus eurhythmus; Jerdon's Baza, Aviceda jerdoni; Lesser Fish Eagle, Ichthyophaga humilis; Pied Falconet, Microhierax leucopterus; Grey-headed Lapwing, Vanellus cinereus; Yellow-vented Pigeon, Treron seimundi; White-bellied Pigeon, Treron sieboldi; Coral-billed Ground Cuckoo, Carpococcyx renauldi; Spot-bellied Eagle Owl, Bubo nipalensis; Tawny Fish Owl, Ketupa flavipes; Brown Hornbill, Anorrhinus tickelli; Blue-rumped Pitta, Pitta soror; Swinhoe's Minivet, Pericrocotus cantonensis; Green Cochoa, Cochoa viridis; Jerdon's Bushchat, Saxicola jerdoni; Grey Laughingthrush, Garrulax maesi; Red-tailed Laughingthrush Garrulax milnei; Spotted Wren Babbler, Spelaeornis formosus; Spectacled Fulvetta, Alcippe ruficapilla; Rufous-throated Fulvetta, Alcippe rufogularis; Lesser Rufous-headed Parrotbill, Paradoxornis atrosuperciliaris; Black-breasted Thrush, Turdus dissimilis; Yellow-vented Warbler, Phylloscopus cantator; Fujian Niltava, Niltava davidi; Japanese Paradise-flycatcher Terpsiphone atrocaudata; White-winged Magpie, Urocissa whiteheadi; Indochinese Green Magpie, Cissa hypoleuca.

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