Spatial and seasonal distribution of Bee Pollinator Species in a Sudanese Agro-ecological System in Burkina Faso, West Africa

Bees are the most important pollinators of many crops and wild plant species. The ecosystem service of pollination provided by these insects is crucial to maintain overall biodiversity and to secure crop yields worldwide. Especially improving the livelihood of smallholders in developing countries through higher crop yields is essential for achieving global food security and poverty reduction. However, ecosystem degradation, depletion of plant species, habitat fragmentation, use of insecticides and global warming constitute severe threats to these organisms with some being clearly at risk of extinction. Despite the great ecological and economic importance of bees as pollinators, hardly anything is known about the bee species in West Africa and particularly in Burkina Faso. The study aimed to assess bee communities of a Sudanese agro-ecological system in Burkina Faso. We investigated the diversity and abundance of bees in near-natural savannah habitats and in nearby fields of the main cash crops (cotton, sesame) at three sites in the south of the country. Bees were caught with 288 colored pantraps for the duration of one year, covering the dry and rainy season. A total of 105 species of bees belonging to 32 genera and 4 families (Apidae, Megachilidae, Halictidae, and Colletidae) were identified. The most diverse family was Halictidae (sweat bees) with 41 species. The family of Apidae (including honey bees, bumble bees and stingless bees) was the most abundant family including 92.57% of specimens collected. In this study, the stingless bee Hypotrigona gribodoi was the most abundant species with 74.55% of all specimen. However, general conclusions have to be drawn with caution, since species abundances can greatly differ from year to year. During our study time, we noticed that the greatest number of species and specimens of bees were obtained in the dry season because of the longer duration of the season. However, the peak of the diversity and abundance of bees was observed in the rainy season especially in July and August (months of intense rains). The assessment of bee species and their seasonal distribution is an important scientific basis for the establishment of appropriate management strategies and can be implied in terms of sustainable agricultural practices that insure better productivity due to bee pollination service provision and biodiversity conservation. Keywords: Biodiversity - Pollination - Bees - Ecosystem service - Agriculture - Burkina Faso.