The IBA is centred on the Phou Louey massif, the most extensively forested part of Phou Louey Protected Area, in northern Lao P.D.R. The massif supports mixed deciduous and semi-evergreen forest on its lower slopes, lower montane evergreen forest between 1,500 and 1,800 m asl and upper montane evergreen forest above 1,800 m asl. There are also some areas of secondary grassland within the IBA, where the forest has been cleared for cultivation. The IBA supports a rich and distinctive montane avifauna, including the globally threatened Beautiful Nuthatch Sitta formosa. In addition, Rufous-necked Hornbill Aceros nipalensis has been recorded, and, given the relatively large area of mature forest, the IBA may support a significant population of this species. Furthermore, the IBA also contains significant stretches of forested streams, which are important for Blyth's Kingfisher Alcedo hercules (Davidson 1998). Finally, Yellow-vented Warbler Phylloscopus cantator, a restricted-range species, is suspected to breed at the IBA. If this were confirmed, the IBA would qualify for inclusion within the Eastern Himalayas Endemic Bird Area.
Breeding is suspected but unconfirmed for Yellow-vented Warbler. This species may also breed at Nam Ha Protected Area, at the other site in Laos. However the species is probably a winter visitor at that site.The area does not support many the IBA key species of birds (Ai and Aii criteron), but supports many Biome-restricted assemblages. It is maybe one of few breeding sites for Yellow-vented Warbler known occur in Laos so far.
Non-bird biodiversity: Davidson (1998) recorded four species of primate: Slow Loris Nyticebus coucang, Assamese/Rhesus Macaque Macaca assamensis/mulatta, Bear Macaque M. arctoides, White-cheeked Crested Gibbon Hylobates leucogenys. Villagers reported Francois's Langur Semnopithecus francoisi but not confirmed with further substantiating evidence.There were reliable reports from two local villagers, Ban Nampoung and Ban Sakok that four species of turtles present at the IBA area Big-headed Turtle Platysternon megacephalum, Four-eyed Turtle Sacalia quadriocellata, Impressed Tortoise Manouria impressa and Asiatic Softshell Turtle Amyda cartilaginea. However the sites of collecting animals were not confrimed clearly. (Davidson 1998)Davidson (1998) recorded two species of ungulate: Gaur Bos gaurus and Southern Serow Naemorhedus sumatraensis. Villagers reported another two species of ungualate also present, but not confirmed by with further substantiating evidence: Indochinese Warty Pig Sus bucculentus and Banteng B. javanicus.
Pressure/threats to key biodiversity
The major threats to biodiversity at the IBA are clearance of forest and hunting. Forest is cleared for shifting cultivation or burnt to promote new growth for grazing livestock. However, the extent of forest clearance is lower within the IBA than in surrounding areas. Hunting pressure at the IBA is high, and takes place for subsistence, to supply the wildlife trade and to protect crops and domestic livestock from depredation. With the notable exception of hornbills, subsistence hunting is not considered to be a high threat to most species of conservation concern. Hunting for trade, however, is believed to be a severe threat to targeted species, such as turtles (Davidson 1998).
The Phou Louey Protected Area is directly adjacent to the Nam Et Protected Area and their combined areas totals 338 000 hectares.