Bonobo Food Items, Food Availability and Bonobo Distribution in the Lake Tumba Swampy Forests, Democratic Republic of Congo

ABSTRACT

Data on food items were collected from the Lac Tumba Swampy Forests (LTSF) with the objective to gauge the effect of food type and availability on the distribution of the bonobos. Bonobos at the LTSF feed on at least 61 plant species and eat more Terrestrial Herbaceous Vegetation (THV) than at other sites (t = 0.676, df = 3, p = 0.548 > 0.05; insignificant). Fruits were available for most of the year at sites within the LTSF. At the Mbou-Mon-Tour (MMT), a site with higher bonobo density, the mean density of 1.42 fruits/m2 per month (range 0.62 – 3.82 fruits/m2 per month) was recorded, higher than in other sites where bonobos occur (general univariate linear model β = 0.422, t = 1.543, df = 11, p = 0.151, non-significant). In-site differences between MMT and other sub-sites in the LTSF were significant (t = 2.793, df = 12, p = 0.016 < 0.05). Fruit abundance in the LTSF ( X =138 fruits/km, SD = 13.80) was higher than in the Salonga National Park (SNP) ( X =83 fruits/km, SD = 6.49). There were five species of THV in the LTSF, with the most abundant being Megaphrynium macrostachyum (41.18%), which was scarce in the Lomako Forests. Comparisons between sites indicated that sites in SNP consistently had lower stem densities than sites in LTSF (t = -7.528, df = 3, p =0.005, significant). These results, in agreement with previous studies, concluded that the distribution of THV in different sites significantly determined the bonobo distribution.