Composition and interaction network of flower-visiting insects in Obafemi Awolowo University, Parks and Gardens, Ile Ife, Nigeria

Abstract

Insect-flower interactions in crop fields and native vegetation habitats have been well studied. However, there is paucity of information on the flower-visiting insect communities of ornamental flower gardens and lawns especially in south-west Nigeria. This study examined the flower-visiting insect community of Obafemi Awolowo University Parks and Garden and their interactions with ornamental plants. Flower-visiting insects were sampled using three complementary sampling methods (Coloured pan traps, sweep netting along transects and timed observation within quadrat). The combination of sampling methods was to prevent bias of individual methods against some insect taxa. The insects collected belonged to 21 species classified into 10 different taxa. Bees (23.14%) and butterflies (26.24%) had the highest percentage composition of the insects collected while the least was observed in beetles (0.74%), wasps (1.49%) and midges (1.36%). Significant variation was observed in the attractiveness of the different species of ornamental plants to flower-visiting insects. Hemilia patense and Caluna vulgaris had the highest attractiveness in terms of mean abundance value 3.100 1.434 and 1.800 0.604 respectively of flower-visiting insects. Obafemi Awolowo University Parks and Gardens support a diverse community of flower-visiting insects and ornamental plants. The potential of these ornamental plant species as alternative source of floral rewards for flower-visiting insects and for promoting insect-flower interactions in urban ecosystems should be further investigated.

Keywords: Biodiversity; conservation; pollinators; ornamentals; flowering plants