Langoué Bai

Langoué baï is an ancient forest clearing nestled within a vast stretch of forest – a mixture of the Atlantic coastal forest of Lower Guinea, and semi-deciduous forest typical of central Congo Basin. The baï (a B’aka word for ‘a clearing with a river flowing through it’ or ‘where the animals eat’ depending on who you ask) is likely formed as a result of a vast slab of granite rock close to the surface limiting large tree growth, and the trampling, grazing, and defecation of various animals which use the site to feed, drink, socialise, and to obtain minerals. The clearing boast up to 90 different forest elephants visiting per day during peak seasons, with more visiting at night, as well as multiple gorilla groups, forest buffalo, huge droves of red river hogs, and a resident population of sitatunga. Birds also make use of the clearing, from the common hammerkop to the endangered Hartlaub’s duck, as well as innumerable passerine species flitting along the forest edge and birds of prey such as the vulturine fish eagle. Dragonflies obelisk while occasional waves of butterflies break from the tree line. Archaeological findings show human habitation of other nearby clearings as recently as 4000 BP, and of the area around the current Ivindo train station and around the park in general from as early as 120,000 BP to the modern day.

The baï’s rediscovery in 2000 by Mike Fay during the MegaTransect, a 2000 mile hike through some of the most remote and expansive forests left on Earth, was an important moment in Gabonese conservation. Recognising its ecological and touristic value, the site played a key role in demonstrating the urgent need for a network of protected areas to conserve Gabon’s unique flora and wildlife for future generations and for the long-term benefit of local people.

While the baï is undoubtedly a particular gem, the whole region of forest in the greater Langoué area is important ecologically, with many endemic and rare tree species, under and over which walk leopards, aarvark, pangolins, and chimpanzees. A network of baïs of varying sizes (of which Langoué is the largest) runs east to south west, each important for a varying set of species. The same individual elephant has been observed at multiple baïs, and the area as a whole is no doubt vital for the large number of elephants that move within it.

WCS’s research

Since 2001, even before Gabon’s 13 national parks were gazetted in 2002, WCS has conducted scientific monitoring of multiple fauna and flora species in the greater Langoué area, as well as hosting student projects from around the world, and conducting a pilot tourism operation between 2001 and 2008.

Langoué Research Station

A camp constructed in 2005 acts as the hub of research in the greater Langoué area, and hosts WCS staff, external researchers and students, and ANPN ecoguards. Power is provided by a large solar power system with enough capacity to run and charge laptops, scientific equipment, sat phones, lights, and an HF radio used to communicate with the WCS logistics centre in Ivindo, where support staff are based.

Current & on-going research


Since 2001 elephants visiting Langoué Baï have been the core focus of WCS’ research and protection work. More than 1,400 individuals have been identified using a combination of identification cards, photos, and databases. Monitoring is carried out by dedicated research assistants who live at Langoué camp during their 42 days missions, spending most days between 8am and 4pm at the platform overlooking the baï, making observations.

This research is important for understanding why and how elephants use these forest clearings, but also more critically for supporting Ivindo National Park’s management. For example, a recent WCS analysis using these data showed a decline in the number of older males visiting the baï since 2002, suggesting poaching around the park is having an impact on the population structure of these threatened animals.


Gorilla monitoring first took place between 2001 and 2008. It was recently restarted in 2013 by a dedicated gorilla research assistant, who identifies every group entering the baï, as well as individuals. Analyses of the long-term data sets have shown clear changes in the demographic structure and the prevalence of visual diseases. This is giving us insights into ape health and disease recovery which is valuable for conservation efforts of wild populations.

Multispecies monitoring

A system of ‘instantaneous scan sampling’ is used to monitor presence of 6 different species in the baï – elephants, gorilla, sitatunga (a kind of swamp antelope), potamochère (also known as red river hogs), forest buffalo, and otters. This research allows us to find patterns in daily and seasonal use of the baï by these species, as well as to flag up declines in number or other problems.


Following training from the Elephant Listening Project by Cornell University, a WCS research assistant is now able to deploy and maintain acoustic recording devices, then recuperate and analyse the data they collect. This useful monitoring method allows insight into sites without research presence, and is used to track elephant activity as well as signs of poaching like vehicle noise and gunshots.


Langoué acts as a host for an a subproject of the Global Ecosystem Monitoring network (GEM), an international effort to measure and understand forest ecosystem functions and traits, and how these will respond to climate change. Aiming to provide a comprehensive description of the carbon cycle of African forests, this project is funded by a NERC grant and the ERC Africa GHG project, and centres on the establishment of intensive plots in both intact and logged forests in Ghana and Gabon.

Latest Publications

All Publications >>

Email from:
Email to:

The person you email to will see the details you enter in the Form field and will be given you IP address for auditing purposes

Key Staff

Olly Griffin
Forest Carbon Technical Advisor


WCS Gabon
Libreville, BP 7847 Battery IV, seated CIMA
+241 44 40 39