Odzala National Park - Biodiversity

Biodiversity

The savannas have a low biodiversity, both in terms of plants and mammals. The mammal species that are truly savannicole or species of edge habitat include Grimms' duiker, bushbuck, and spotted hyaena, although the latter seems to have found a niche in the forest near marshy clearings in Odzala. Forest buffalo are found in large troops in the savanna, whereas they are normally found in small groups of up to 12 in forest. The savannas are being recolonized by forest, both from the existing forest edge and from small thickets originating on termite mounds within the savanna itself. Until the late 1990s, lions lived in the park and the savannahs to the south, but now seem to have gone - not only from here but from the whole of the Bateke Plateau, where they were once not uncommon.

Within the forest bloc, swampy forest clearings provide abundant digestible forage for herbivores such as gorillas, buffalo, sitatunga and Giant Forest Hog. In addition, some of these clearings have salt-rich soils, which attracts elephants as well as other mammals. These clearings are probably maintained by the action of the larger herbivores, and provide the rare opportunity of observing forest species which are normally extremely difficult to see.

Density estimates of apes and elephants have been calculated from the park. Comparison of these results and of data obtained elsewhere using the same methodology shows that Odzala has high densities of both of these species; the open canopy Marantaceae forests have a particularly high gorilla density, and closed canopy Marantaceae forests have a high chimp density. It is probable that the Marantaceae itself is an important keystone resource in Odzala, as has already been proposed for Lopé National Park in Gabon. The riverine forests are used by all eight monkey species which occur in the park, and four of these are never or rarely seen in forests of terra firma (Cercopithecus neglectus, Miopithecus talapoin, Colobus guereza, Cercocebus galeritus). The rivers and marsh forests are also important for other species such as hippo, chevrotain, sitatunga, Nile Monitor, dwarf forest crocodile and Crocodylus cataphractus, and the marshy clearings mentioned above are also very important for the large mammals of the region.