Sympatric species of African acacias provide forage to honeybees throughout the year in the Sudan savanna

Abstract

The survey was conducted from January to December, 2016 and 2017 respectively, in Bauchi state, Nigeria. In the first year, weekly visits were made to determine the beginning and end of the flowering of each species; while in the second year visits were made at irregular intervals to confirm the observations made in the previous year. The relative importance of the species, as forage for honeybees, was subjectively assessed through the frequency and intensity of visit by foragers. The species was rated “very important” if foragers were abundant on it throughout the dehiscent phase of the flowers. On the other hand, if a substantial number of foragers foraged continuously on the species, this species was ranked “important” and a species on which foraging was sporadic and by a relatively smaller number of foragers was adjudged “less important.” Period of bloom ranged from six weeks in Vachellia sieberiana to 19 weeks in V. hockii. Senegalia senegal, V. seyal, and S. ataxacantha were ranked very important; V. nilotica, V. hockii and Faidherbia albida important; and V. sieberiana and V. polyacantha less important. It was observed that the complete overlap of the flowering periods of the various species provided forage to honeybees, and other foragers, throughout the year.