Biodiversity in the Bai
In the rainforests of Central Africa, the bai, or forest clearing, is an oasis of life. As ecosystem engineers, elephants create habitat for many other fascinating and threatened species. A visitor to the bai might see bongo antelope, red river hogs, apes, and even African grey parrots foraging for mineral-rich mud and grasses¹. The Congo Basin region is home to more than 148 mammal species and 678 bird species2. 3,000 of these species are endemic, meaning they exist nowhere else in the world². Because of its biodiversity, the Congo Basin has been an area of interest for biologists. Recently, a few key species have been the focus of research studies and conservation projects which have revealed amazing animal behaviors and offered valuable information for conservationists.
The Western Lowland gorilla is the most numerous of all gorilla subspecies but is still considered critically endangered due to disease, poaching, and habitat destruction³. A 2018 study estimates that the gorilla population is declining by a startling 2.7% every year⁴. Western gorillas are smaller than other species and have shorter, brown-grey coats, and wider skulls⁵. Their diet consists of grasses, leaves, fruit, and other foliage found in the forest or in the marshy bais. Family groups, led by a male silverback leader, contain an average of 9 gorillas⁶. Since 1993, the Mbeli Bai Project has identified 460 gorillas living within the Nouabalé Ndoki National Park⁷. A high wooden platform built on the bai has given scientists an unprecedented view of the elusive gorillas, which are otherwise difficult to track in the dense forest⁸.
Over the years, scientists’ observations have revealed new insights into gorilla social structure and life history⁸. For instance, they have found that western gorillas mature slower than mountain gorillas, which could make it harder for the population to recover after poaching⁹. Gorillas at Mbeli Bai have also been observed using tools — the first evidence for tool use in wild gorillas¹⁰. In one instance, a female gorilla used a branch as a ‘walking stick’, holding it upright to stabilize herself and measure water depth as she crossed a pool of water¹⁰.
The Mondika Gorilla Project is another long-term study located just outside Nouabalé Ndoki National Park, in the Djeke Triangle Area⁸. Since 1995, Congolese trackers have followed gorilla families through the forest, habituating them to the presence of humans in order to make data collection easier. So far, two gorilla families, led by silverbacks “Kingo” and “Buka”, have become accustomed to humans, giving the trackers an intimate look into gorilla family dynamics and even individual personalities. Researchers hope this area will become a prominent eco-tourism spot.
Bongo antelopes are another common visitor to the bai, where they nibble on the tender new plant growth and visit the mineral licks¹¹. Their diet consists of leaves, shrubs, grasses, and fruits¹². They are the largest forest antelopes and their pattern of long white stripes help them to identify each other in the underbrush. Bongo males are mostly solitary but females and young live in herds and forage together¹². Bongos have even been found to have symbiotic relationships with birds in the bai: the birds eat their parasites and the birds alert them to predators¹³. Bongos are considered “Near Threatened” and the population has declined 20% in the past three generations¹². In 1997, an infestation of biting flies and an increase in trophy hunting took its toll on the animals. After a population study established that the number of Bongo was declining rapidly, the Nouabalé Ndoki National Park lowered the hunting quota to only 3 bongos per year¹⁴.
While gorillas and bongo antelope forage for grasses in the bai, African grey parrots wing overhead. These grey birds with striking scarlet tailfeathers descend in large flocks to eat seeds, grasses, and fruits. They nest in tree cavities above the ground and roost in groups of up to 10,000 birds¹⁵. African grey parrots are very intelligent and skilled at mimicking human speech, which has made them one of the most popular pet parrots. Unfortunately, the pet trade has dramatically depleted their population. The trapping methods poachers use are very damaging to the birds and it is estimated that only one in twenty parrots will even survive long enough to be sold¹⁶.
In 2016, CITES placed a ban on the trade of the parrots and the IUCN updated their status to endangered¹⁷. There have also been efforts to apprehend smugglers before they leave the country and release the captured parrots. The Wildlife Conservation Society of Congo (WCS-Congo) runs a rehabilitation center for African greys in Bomassa, a town near Nouabalé Ndoki National Park. In 2018, 36 healthy parrots were successfully released into the National Park¹⁸.
Gorillas, bongo antelope, and African grey parrots are just three examples of the many species that live alongside our forest elephants and make the bai an enchanting place for research. Although habitat destruction and human activity threaten this lush ecosystem, prompt action can help populations bounce back. Biodiversity hotspots like the Congo Basin offer us hope for the future. If protected, these strongholds of nature can turn the tide for wildlife around the world.
References:
¹ “WWF in Congo.” WWF. World Wildlife Fund. Accessed March 6, 2020. http://www.wwf-congobasin.org/where_we_work/republic_of_congo/.
²“Initiatives: Wildlife Health.” WCS Congo. Accessed March 6, 2020. https://congo.wcs.org/Initiatives/Wildlife-Health.aspx.
³“Research.” Goualougo Triangle Ape Project . Accessed March 6, 2020. http://www.congo-apes.org/research/.
⁴“Largest Study Ever in Western Equatorial Africa Shows Gorillas in Deep Trouble.” WCS Congo Blog, September 24, 2019. http://wcscongoblog.org/largest-study-ever-in-western-equatorial-africa-shows-gorillas-in-deep-trouble/.
⁵“Western Lowland Gorilla.” WWF. World Wildlife Fund. Accessed March 6, 2020. https://www.worldwildlife.org/species/western-lowland-gorilla.
⁶“Wildlife: Western Lowland Gorilla.” WCS Congo. Accessed March 6, 2020. https://congo.wcs.org/Wildlife/Western-Lowland-Gorilla.aspx.
⁷“Mbeli Bai.” WCS Congo Blog, May 16, 2017. http://wcscongoblog.org/mbeli-bai/.
⁸Arnhem, Eric. “Wild Places: Nouabale-Ndoki National Park.” WCS Congo. Accessed March 6, 2020. https://congo.wcs.org/Wild-Places/Nouabale-Ndoki-National-Park.aspx.
⁹Breuer, Thomas, Mireille Breuer‐Ndoundou Hockemba, Claudia Olejniczak, Richard J. Parnell, and Emma J. Stokes. “Physical maturation, life‐history classes and age estimates of free‐ranging western gorillas — Insights from Mbeli Bai, Republic of Congo.” American Journal of Primatology: Official Journal of the American Society of Primatologists 71, no. 2 (2009): 106–119.
¹⁰Breuer, Thomas, Mireille Ndoundou-Hockemba, and Vicki Fishlock. “First observation of tool use in wild gorillas.” PLoS Biology 3, no. 11 (2005).
¹¹Arnhem, Eric. “Wildlife: Bongo.” WCS Congo. Accessed March 6, 2020. https://congo.wcs.org/Wildlife/Bongo.aspx.
¹²“Bongo.” African Wildlife Foundation, July 1, 2019. https://www.awf.org/wildlife-conservation/bongo.
¹³Ruggiero, R. G., and H. E. Eves. “Bird–mammal associations in forest openings of northern Congo (Brazzaville).” African Journal of Ecology 36, no. 2 (1998): 183–193.
¹⁴“Securing a Brighter Future for Bongo.” WCS Congo Blog, May 17, 2019. https://wcscongoblog.org/securing-a-brighter-future-for-bongo/.
¹⁵BirdLife International 2018. “Psittacus erithacus.” The IUCN Red List of Threatened Species (2018)
¹⁶“Parrots in Peril.” WCS Congo Blog, June 23, 2017. http://wcscongoblog.org/parrots-in-peril/.
¹⁷Kooistra, Michelle. “Grey Parrot.” World Parrot Trust. Accessed March 6, 2020. https://www.parrots.org/projects/grey-parrot.
¹⁸“Parrots Fly Free from Bomassa Rehabilitation Centre.” WCS Congo Blog, September 13, 2018. http://wcscongoblog.org/parrots-fly-free-from-bomassa-rehabilitation-centre/.
