Habitat: Mostly dry evergreen/semi-evergreen forest on high relief terrain (500 m -1200 m) with some areas of mixed deciduous. The Nam Kading valley is dominated by broadleaf evergreen forests with a high density of large trees. Forest shows high species diversity with 83 tree species recorded in a sample of 428 individuals from two areas.

Access: Route 13 south and Route 8 skirt the
southern and southeastern boundaries. There are no roads within the NPA and the rivers are not navigable. Steep, often precipitous slopes mean that access to most areas is only by foot and arduous.

Complete Profile

Physical Features:

The terrain is very rugged with large bolder strewn streams and spectacular cascades.The area ranges in altitude from around 140m at the Research and Training centre to 1588m.

Four main rivers cut through the NPA. The major one, the Nam Kading, which means “Water like a bell”, gives its name to the protected area. The Nam Kading is a major tributary to the Mekong River, and its catchment area covers approximately 92% of Bolikhamxay Province, approximately 15,977km² and cuts through the NPA from north to south. The remaining three rivers (the Nam Muan, Nam Sat and the Nam Tek) cut the NPA into four mountain ranges: the Phou Louang range, the longest, to the southwest; the Phou Ao range to the southeast; the Thalabat range to the northwest; and Pa Guang range in the northeast. Visit: Namkading


Surveys in Nam Kading have documented many endangered species.  There are at least 13 globally and 12 regionally threatened mammals. Gaur, sun bear, and both northern and southern white-cheecked crested gibbon are present, making the area particularly important for gibbon conservation.

Lao PDR National Protected Area Network:

The Lao People's Democratic Republic (Lao PDR or Laos) is home to the most abundant and intact ecosystems in the Indochina Peninsula. Laos embraces four of the Global 200 Eco-regions, the richest, rarest, and most distinct examples of the Earth's diverse natural habitats, which are critical for biodiversity conservation and global sustainability.

To help protect this stunning natural beauty the Lao government has designated a National Protected Area (NPA) network to conserve all key habitats and ecosystems. This network of 20 NPAs covering 14% of the country is recognised as one of the best designed in the world.

To gain a real insight into the heart of Laos you can visit NPA's from the north to the south of the country, discovering diverse habitats and lifestyles in areas ranging from mountain peaks to wetland plains. Your visit will contribute to the conservation of unique ecosystems and traditions that have shaped Laos over generations.



Nam Kading. Abbreviated: NKD


Established by PM Decree 164, 29 October 1993


Latitude: 18o 11' - 18o 39' N
Longitude: 103o 54' - 104o44' E

Map Sheets

Scale I: 50,000

Scale I: 100,000

E 48-53

E 48-54

E 48-65

E 48-66

Scale I: 200,000

E 48-XIV

E 48-XV

Scale I: 500,000

E 48-A








To the W and S follows the foot of the hills that rise abruptly from the Mekong lowlands.
To the E follows the Nam Ao and Nam Xouang, and then foot of hills in the Nam Mouan valley, avoiding settled area on the valley floor.

NW boundary follows the Nam Sun.


Area As decreed: 1690 sq. km
As proposed in Berkmüller et al. (1995): 1740 sq. km
Best estimate 1570 sq. km


Berkmüller's (1995) boundary excised the inhabited ? area in the Nam Pheung valley which has been heavily degraded by shifting cultivation. In the NW, the boundary was extended about 10 km beyond the Nam Sun, into a lower area of forest. A sizeable extension was included in the SE, comprising the Nam Ao valley and part of the Nadi limestone massif.

Forest corridors have been advocated to link NKD to the Khammouan Limestone - Nakai Nam Theun complex to the S and Nam Chouan PNBCA to the E. The KL corridor is proposed to include the NE fringe of the Nam Hai/Hinboun plain and forested ridges bordering the Nam Theun. Assessment of the best location for the Nam Chouan corridor awaits field surveys in that area. It is suggested that the cooridors would be managed as buffer areas, with sustainable local extractive uses permitted, but commercial logging forbidden.


Route 13 (S) and route 8 skirt the S and SE boundaries. A dry season track runs from route 8 to villages on the SE boundary, and a logging road from Khamkerd district through Viengthong reaches the NE of the area.
There are no roads within the NBCA itself, and the rivers are not navigable. Steep, often precipitous slopes mean that access to most areas is only by foot and arduous.

Villages &

No. of villages by type







Persons ...


Note: No villages in main part of NBCA

Principal Local

Local people enter the area only occasionally for specific activities, such as to hunt or collect Mai Dam.




Two helicopter overflights to assess habitat (Nov./ Dec.)


'Ground' survey in June


Selected for management planning and implementation during 1991-1995 by LSFCP and IUCN. This did not occur.


Abandonment of Ban Donme - evacuation was requested by locals due to security concerns.


NBCA declared.


WCS field surveys to assess impacts of planned Theun-Hinboun and Nam Theun 1 hydropower projects (late '94 - early '95).


Theun-Hinboun became operational (31.03.1998).


Nam Theun 1 project suspended until this date, when its economic viability is due to be reviewed (Hydropower Office, verbally).



The Main body of Nam Kading is formed from a massif of steep, densely forested hills at altitudes mostly from 500-1200 m. The area is traversed by the Nam Kading river, which flows from the S to the W boundary, and the Nam Mouan, which enters the area from the E and joins the Nam Kading close to the centre of the NBCA. These major rivers generally form a steep valley system, except around the former settlement of Ban Donme, where the banks of the Nam Kading are gently sloping. The streams that feed these rivers from the surrounding hills are generally seasonal.
Exposed rock faces are common, and are especially impressive along the SW border. The escarpment along the W boundary is formed by a major geological contact between the Mz1 and Mz2 units (difficult to make sense of this without more info on local geology - Mz2 are Cretaceous red sandstones, but Mz1, which forms the vast bulk of the NBCA, includes a large range of different facies).
Berkmüller's (1995) extensions include areas of lower hill forest to the NW and SE, and an area of high altitude limestone karst.


160m - 1600m.


On high rainfall finger which extends ENE from NNT to PKK. How is this formed? - air currents from central Thailand rising as it reaches uplands on the E side of the Mekong, or wet air from Vietnam ?

Main Forest

Mostly dry evergreen/semi-evergreen forest on high relief terrain, but some areas of mixed deciduous. The Nam Kading valley is dominated by broadleaf evergreen forests with a high density of large trees, and of species attractive to frugivores. Surveyors in 1994-1995 considered much of the forest to show signs of past disturbance from fire or cultivation. The natural influence of topography and soil type is not well understood, however, and the forest does show high species diversity with 83 tree species recorded in a sample of 428 individuals from two areas. Three species of dipterocarp accounted for a large percentage of trees recorded.
Forest in the lower relief Nam Ao valley showed large differences in species composition.

Other Habitat

The stretch of the Nam Kading passing through the NBCA was the most pristine lowland riverine habitat in Laos . It also appeared to form an appreciable biogeographic boundary for arboreal groups such as Callosciurus squirrels and langurs. These values must have been seriously impacted by the Theun-Hinboun hydropower project, however.


Vertebrate Class

No. of Species

No. of Key Species










Note: only figures in bold text considered result of adequate survey.

Key species follow Duckworth et al. in press. Numbers in ( ) are additional provisional records.
Mammal figures only refer to large mammals, a further 26 bat spp have been recorded from the area. Also, fish have been surveyed according to WCS.

Survey effort


Principal Contributions to the NBCA System


  • Mid/high ranking site for biological importance. Most valuable of the Annamite Fringe NBCAs (Ling 1999), and most important NBCA for evergreen forest conservation in biogeographic subunit 10A after Xe Pian (Berkmüller 1995).
  • Good numbers of key species for both birds and mammals, including populations of Elephant, Gaur, Giant Muntjac, gibbons, Sooty Babbler and Rufous-throated Fulvetta.
  • Two species of bird not recorded in any other NBCA, including Pale-capped pigeon (GT-VU;LKL), and one of only two NBCAs with confirmed records of Binturong (ARL).
  • In comparison to other NBCAs, the individual populations of the following key species are especially significant - River Lapwing, Wreathed and Great Hornbills, Wire-tailed Swallow, Rufous-throated Fulvetta, large otters, and potentially Francois' Langur on the Nadi limestone.

Note: All these conclusions are based on assessments made before the Theun-Hinboun hydropower plant became operational. The extent of remaining biodiversity values depends greatly on the severity of the impact of that project, and can only be determined by a renewed program of field surveys.


  • Presumably high if Nam Theun 1 goes ahead. Although NBCA may only be a minor component of the catchment, the maintenance of good forest cover would probably be critical to reducing siltation rates.
  • Probably not an important source of water for local communities.



Recreation &

  • Potentially substantial - impressive scenery and forests, and located on the main overland tourist route from Vientiane to Vietnam .
  • Greatest single asset, the Nam Kading, is already severely damaged, however, and the Theun-Hinboun plant itself may disfigure the area.


  • The Theun-Hinboun hydropower plant operates by diverting flow from the Nam Kading to the Nam Hai outside of the NBCA. A minimum flow of 5 m3s-1 is maintained in the Nam Kading for 14-18 weeks during the dry season. The Nam Kading was the most important feature of the area for wildlife, and the effects of the project on its ecology must have been considerable. Populations of River Lapwing, Long-billed Plover, Crested Kingfisher, Wire-tailed Swallow, Dhole, large otters, Asian Small-clawed Otter, Tigers/large cats, and Elephants - and probably also Gaur, Rhesus Macaque, Lesser Fish-eagle and Siamese Fireback - were predicted to be seriously affected by the project. The severity of these effects to date, and the degree to which they might be reversed or mitigated are unknown. The indirect effects of the project, due to increased access to the area by construction/project staff or infrastructure development nearby, are similarly unknown. The Theun-Hinboun Hydropower Project has no environmental policy to address these auxiliary impacts (E. Hourihan, verbally).
  • If it goes ahead, the Nam Theun 1 hydropower project will flood a considerable area of riverine forest on the easternmost stretch of the Nam Kading before it exits the NBCA, impounding a large depth of water in a dendritic reservoir. The project can also be expected to produce additional negative impacts due to increased access to the NBCA interior and the presence of construction/operating staff in the area.
  • Hunting has doubtless already had an effect on populations of large vertebrates, although possibly not to the same extent as in other NBCAs, due to the difficulty of access. One hunting party of >70 individuals was observed by survey team members en route to Ban Donme in the centre of the NBCA.
  • Shifting cultivation in the Nam Pheung Valley .
  • Security, especially in the NE section of the area - the current situation is unclear. 

Reasons for
Extensions or

  • Berkmüller's (1995) boundaries were drawn so as to maximise coverage of mature forest and minimise the inclusion of heavily degraded areas.
  • Additionally, the Nam Ao valley was proposed for inclusion due to the differing faunal and floral character of its lower-lying forests, and the Nadi Limestone because high altitude karst is poorly represented elsewhere in the Lao PA system.
  • The forest corridors are proposed to contribute towards an extensive complex of protected areas in Central Laos , maintaining gene flow between sub-populations of large vertebrates, and buffering against environmental change. It is hope that the habitat links to the KL and NNT will capture established Elephant migration roots.







Support &

None at present.
Proposed to JICA by DoF.



  • Ensure sufficient dry season flow in Nam Kading.
  • Assessment and monitoring of extractive uses and prevention of settlement along Nam Kading valley.
  • At present the main body of the NBCA enjoys substantial natural protection due to its inaccessibility, and emphasis should be placed on delineating and protecting more vulnerable peripheral areas. Such initiative should include terminating cultivation in the E of the NBCA, countering habitat clearance in the Nam Ao and Nadi Limestone areas, and monitoring of civil and commercial development in the corridor areas.



 Berkmüller, K. et al. (1993). Protected Area System Planning and Management in Lao PDR: Status Report to mid-1993. LSFCP/IUCN, DoF.

Berkmüller, K. et al. (1995). Protected Area System Planning and Management in Lao PDR: Status Report to mid-1995. LSFCP/IUCN, DoF.

Duckworth, J. W. et al. (1999). Wildlife in Lao PDR: 1999 Status Report. IUCN/WCS/CPAWM.

EWI (1994). Nam Theun 1 Hydroelectric Project, Lao PDR. Report by Electrowatt Engineering Services to Siam United Service Public Co.

Flint , C. (1999). Data/Information on Conservation Management and Protected Areas in the Lao PDR. CMS & TNA Project, DoF.

Ling, S. D. (1999). A Biological System of Prioritisation for Protected Areas in the Lao PDR. Report to WCS.

Norconsult (1994). Theun-Hinboun Power Project: Summary Environmental Impact Assessment Report. Report to the Ministry of Industry and Handicraft.

Norpower (1993). Theun-Hinboun Power Project Feasibility Study. Part 1. Report to the Ministry of Industry and Handicraft.

Salter, R. E. et al. (1991). Planning and Development of a Protected Area System in Lao: Status Report to mid-1991. LSFCP/IUCN, DoF.

SWECO (1992). Nam Theun 1 Hydropower Project Updating of Pre-feasibilty Study. Phase 1. Stockholm SWECO.

Wildlife Conservation Society (1995a). A wildlife and Habitat Assessment of the Nam Theun 1 Hydropower Project Area. Report to the Committee for Planning and Cooperation of the Government of Lao and Electrowatt Engineering Services.

Wildlife Conservation Society (1995b). A Wildlife and Habitat Assessment of the Theun-Hinboun Hydropower Project Area. Report to the Hydropower Office of the Lao PDR, Ministry of Industry and Handicraft and to Norplan.

Wildlife Conservation Society (1996). Regional Assessment of the Effects on Wildlife of Proposed Hydropower Projects in the Nam Theun/Nam Kading Watershed. Report to Norplan.

Wildlife Conservation Society (1999). A Wildlife and Habitat Survey of the Nam Kading NBCA, Bolikhamsai Province , Lao PDR.