Elephant Presence Shapes Butterfly Communities in an East African Coastal Forest

ABSTRACT

Habitat disturbances shape the diversity and composition of plant and animal species. It is important to distinguish between natural disturbances caused by megaherbivores and anthropogenic disturbances caused by human activity, as different disturbance regimes differently affect biodiversity. In this study, we analyse butterfly diversity and community structure in three forest areas with different habitat disturbances in the Arabuko Sokoke dry coastal forest of south‐eastern Kenya. We assessed butterfly diversity with bait‐traps in primary forest with and without elephants, and in secondary forest characterised by previous human use and where elephants are currently present. In total, we activated 24 traps, eight traps per forest type. We found differences in the butterfly diversity and community structure depending on forest type and disturbance regime. The rather dense primary forest harboured a considerably higher proportion of dark‐coloured forest butterfly species than the secondary forest, particularly in areas with elephant disturbance. The secondary forest has higher butterfly species richness than the primary forest due to the occurrence of savannah species. Correspondence analyses clearly separated the three forest types with respect to community composition. Species occurring also in anthropogenic habitats were significantly more abundant in the secondary forest than in the two primary forest types. Our findings underline that forest type and disturbance regime shape butterfly diversity and community structure. Our study underlines that the effects of natural disturbances and human‐induced disturbances on butterfly diversity differ fundamentally. Natural disturbances such as by elephant activities seem to promote typical forest butterflies.