Fruit-feeding butterfly communities as indicators of forest restoration in an Afro-tropical rainforest

Abstract

There is scarcity of information pertaining to insect colonisation during forest restoration in the tropics. We investigated the pattern and timescale of butterfly recovery along a gradient of forest restoration in an Afro-tropical moist forest in Kibale National Park, Uganda. The restoration forests ranged from 3 to 16years of age. We placed five traps in each of the eight forests along the restoration gradient and sampled butterflies for three days monthly for 12months, beginning in May 2011. We (1) tested for the directional pattern in butterfly species richness, abundance, diversity, dominance and community composition from the youngest restoration to primary forests, (2) assessed the temporal and spatial patterns in butterfly community composition along the restoration gradient, (3) assessed the change in similarity between restoration and primary forests along the gradient, to estimate the time needed for recovery, and (4) determined specialist species characterising each forest age group. We recorded 10,092 individuals, representing 79 species. Butterfly species richness, abundance and diversity increased with age since restoration started. There was a remarkable temporal variation in butterfly community composition. The similarity of the butterfly community to that of primary forests increased linearly with time, without reaching an asymptote. We estimate that fruit-feeding butterfly communities of restored tropical forests can be similar to that of primary forests within 40years, provided that primary forests are nearby. Our results demonstrate that tropical forest restoration aids the recovery of butterfly communities to their pre-disturbance states and probably aids biodiversity as a whole.