The place of Irvingia gabonensis in village communities around the Lobeke National Park in Cameroon

Abstract

The bush mango, Irvingia gabonensis, is one of the most heavily used non-timber tree species around the Lobeke National Park in Cameroon. A survey among fruit gatherers showed that the fruits are collected from the forest floor, which involves very high risks of gorilla attack (100%) and long camping periods (87%). All the gatherers preserve this species, mostly (82%) by protecting wild seedlings, but they are generally reluctant to plant it. However, up to 68% of gatherers indicated that they would be willing to plant the species. The I. gabonensis kernel was ranked by gatherers (98%) as the second main source of food and the first main source of income (93%) among four major Non-Timber Forest Products in the area. An inventory was carried out to determine the abundance of the species in three forest systems: the protected area, a community production forest (a natural forest forming part of the non-permanent forest domain and managed by a village community with the assistance of the forestry administration) and agroforest (fallow land and productive crop/cocoa plantations), in 6 x 3 1-ha plots. Fruit production was assessed by counting fruits during gathering. Seedling growth and survival were assessed only in the protected area because very few seedlings were available in the production forest and agroforest. The overall mean density of I. gabonensis was assessed at 3.3 trees per ha, with no significant difference between the three forest systems. The mean diameter at breast height of I. gabonensis trees in all three forest systems was not significantly different. Mean fruit production in the three forest systems also showed no significant difference. Seedling survival fell to 70% in the protected area after 18 months. The presence of mostly medium to large diameter trees is an indication that the resource will continue to be available for some time but the near absence of younger individuals to replace the ageing population is detrimental to resource availability in the long term. Due to the intensity of gathering, it is recommended that the local population should actively incorporate this species into their farms.