Edible caterpillars and their host plants: ethnobotanical insights in Kwilu, Democratic Republic of Congo.

Abstract

Background: In Kwilu Province, Democratic Republic of Congo, almost 99% of the population eats a variety of edible caterpillars. Many plant species used by humans are also eaten by these caterpillars. Intensive human use of these plants could lead to their gradual extinction. This would directly affect the caterpillars that feed on them and reduce their protein supply to local populations. Assessing these pressures requires a basic understanding of the species involved.

Methods: Semi-structured surveys were conducted with 180 randomly selected informants in the two most populated areas of Kwilu (Masi-Manimba and Idiofa). Questions focused on the 'most consumed' edible caterpillars (i.e. those that are best known and most eaten), their host plants, and how the local population uses them. Caterpillars and branches of host plants were collected during the survey visits. The importance of each cited caterpillar species, their host plant, and the host plant's use category by the local population was assessed.

Results: Seventeen species of 'most consumed' edible caterpillars were recorded, with the Saturniidae being predominant. They feed on the leaves of fifty-one plant species, mostly Fabaceae. There are seven main use categories of caterpillar host plants. Among these, wood charcoal, construction, and slash-and-burn agriculture are estimated to be the primary factors causing the destruction of caterpillar's host plants. Petersianthus macrocarpus (P. Beauv.) Liben and Ricinodendron heudelotii (Baill.) Pierre ex Heckel are preferred by the 'most consumed' caterpillars. Both plant species, along with Erythrophleum africanum (Benth.), hold great cultural importance in Kwilu and are under significant pressure.

Conclusions: The promotion of edible caterpillars through the establishment of plantations for the semi-rearing would contribute to the conservation of these species and make them more available to the local population. Caterpillar preference testing, diet modification and interaction studies between these species would enable better management.