The Seima Protection Forest (SPF) is situated in the foothills of the Annamite mountains. It remains approximately 98% covered by natural vegetation, and contains an unusually high diversity of forest types. The area is unusual in south-east Asia in that it conserves large areas of both evergreen and deciduous forest. The landscape is interspersed with open grassland areas, permanent rivers, water sources and many mineral licks; this diversity of habitats has resulted in a highly productive landscape with the potential to hold large populations of species of conservation concern.
The SPF boasts more than 60 species that are Globally Threatened, Near-threatened or Data Deficient by IUCN criteria. The area is home to 22 different species of carnivore, including Tiger and seven other species of wild cat. The SPF is of international importance for the conservation of primates. It harbours seven species including Germain's Silvered-langur, and possibly the largest populations in the world of Yellow-cheeked Crested Gibbon (at least 2,500 animals), and Black-shanked Douc (over 40,000 individuals). In addition the SPF has regionally or globally important populations of Asian Elephant (estimated at about 115 animals), wild cattle, Germain's Peacock-pheasant and Green Peafowl, among others.