Patterns of diversity and distribution of arboreal social bees' beehives within chimpanzees' home range in a forest-savanna mosaic (comoé national park, côte d'ivoire)

Abstract

The goal of this study was to explain the patterns of diversity and distribution of arboreal social bees nesting in forests of the Comoé National Park, within the homeranges of wild chimpanzees, consumers of their honey. Investigations were done using a total of sixteen plots of one hectare each, established in three habitat types (mature forest island, secondary forest island and gallery forest). The diversity and distribution of arboreal social bees was assessed using visual searches. The exploitation of the beehives of these bees by chimpanzees was also evaluated using honey dipping tools as indicators. Five bee species belonging to two tribes, namely the Meliponini (Meliponula ferruginea, Meliponula togoensis, Meliponula bocandei, Hypotrigona gribodoi) and the Apini (Apis mellifera) were collected. Furthermore, frequent exploitation of the honey of stingless bees by chimpanzees was observed, excepted for H. gribodoi. Beehives of Meliponula ferruginea were identified as the most exploited ones by chimpanzees. A total of 114 beehives were found in the established plots leading to an estimated density of 2.4 beehives/ha within the study area. Among the surveyed habitats, mature forest island was found to harbor the highest beehives' density (4.2 beehives/ha), followed respectively by secondary forest island (1.9 beehives/ha) and gallery forest (1.1 beehives/ha). Finally, all bee species were found nesting in cavities of trees with a DBH ranging from 15 to 87.3 cm, with a special preference for Dialium guinneense. However, the DBH of the nesting trees and the beehives' height measured from the ground level, were found not significantly influencing the honey exploitation by chimpanzees. In sum bee species diversity and distribution might be the most important variables in the survival of chimpanzees within forest-savanna mosaic landscape.