The area consists of the National Park (1,740,000 ha) and adjacent buffer zones of Ouandjia–Vakaga and Aouk–Aoukalé Faunal Reserves (480,000 ha and 330,000 ha, respectively). The park is mainly Sudan–Guinea Savanna woodland, on relatively flat ground and is located in the north-east of the country, where the western edge of the Aouk–Aoukalé Faunal Reserve abuts the international border with Chad. Dominant trees include Terminalia spp., Isoberlinia doka and Anogeissus sp. Along watercourses there is a narrow riparian forest/thicket community, which broadens out in places and even spreads as dryland forest on higher ground. This is of considerable interest, containing as it does a number of southern Guinea–Congo forest species. The low-lying northern part contains extensive flood-plains.
See Box and Table 3 for key species. Some 418 species are recorded from the area, of which 307 certainly or probably breed. Species of global conservation concern that have been reported are Balaeniceps rex, Circus macrourus, Falco naumanni and Glareola nordmanni.Balaeniceps rex may now be no more than a rare visitor (if it were ever otherwise), in view of the drought and lack of modern sightings. In addition to the IBA’s importance for its Sudan–Guinea Savanna biome avifauna, it also holds, at the northernmost distribution limit of some, 15 species of the Guinea–Congo Forests biome (A05; see Table 3). In addition, one Sahel biome species (A03), Ardeotis arabs, also occurs. The site is the only known IBA in the country for no fewer than 35 species.
Non-bird biodiversity: The area is important for a number of mammal species including Panthera leo (VU), Acinonyx jubatus (VU), Gazella rufifrons (VU) and Damaliscus lunatus (LR/cd).
Pressure/threats to key biodiversity
The Aouk–Aoukalé Faunal Reserve to the north of the park has, in the past few years, been invaded by large numbers of cattle. However, the park and associated buffer zone have being managed by the European Union-funded Programme de Développement de la Région du Nord (PDRN) since 1988.