Forage diversity and preferences by honeybees Apis mellifera (hymenoptera: apidae) in Masaka district, Uganda

Abstract

The honey production potential for Uganda and in particular Masaka District has hardly been fully exploited and thus the honey production capacity has since remained low. Knowledge on suitable foraging options for honeybees is a possible key motivating factor for enhancing productivity and hence the success of beekeeping enterprises. This study was intended to identify forage sources of nectar and pollen foraged upon by honeybees, assess flowering phenology and seasonal diversity of honeybee forages in Masaka area and how honeybees respond to their availability. A model apiary with 47 honeybee colonies was selected and honeybee forage studies conducted within a 1km radius of the apiary. A total of 48 quadrats were demarcated along 2 crisscrossing transects and used for data collection during the wet and dry season from March to August 2017. A total of 45 forage species and 25 families were recorded and most commonly Asteraceae and Fabaceae. There was a significant interaction between season and season age on their effect on flora resource availability (p < 0.05). Flowering periods of majority forage species occurred in wet season and were marked from mid to late season. Accordingly, the late wet season demonstrated high average percent cover translating into a period with plentiful foraging resources to support brood growth and honeybee foraging activities. Honeybee forage diversity was significantly different between the wet and dry seasons (p < 0.001) with more diverse flora assemblage in the wet season (Shannon diversity; 1.16). Honeybees had more visits on forage species with different morphological make up although the foraging visits enabled honeybees to collect both pollen and nectar thus demonstrated high visitation on Zea mays, Coffea canephora, Manihoti esculenta, Musa paradisiaca and Callistemon citrinus. Corolla width and inclination were significantly associated with the frequency of honeybee visits to a forage species. Accordingly, forage resources were highly available and diverse in wet season and periodic blooming evident in the dry season. Wild flowers that offer longer bloom periods should be established along edges of the existing Eucalyptus plantation forests and hedge rows and forage plants be preserved in field margins to provide foraging options during agricultural crop off-season scarcity.