Honey DNA metabarcoding revealed foraging resource partitioning between Korean native and introduced honey bees (Hymenoptera: Apidae)

Honey DNA metabarcoding provides information of floral sources of honey and foraging plant preferences of honey bees. We evaluated the floral composition of honey from two different species of honey bees, Apis cerana honey (ACH) and A. mellifera honey (AMH) in a mixed apiary located in a semi-forest environment to understand the floral preference and level of interspecific competition on floral resource. Three honey samples were collected from different hives of each species in mid-August. In total, 56 plant taxa were identified across the honey samples and among them, 38 taxonomic units were found in ACH compared with a total of 33 in AMH. The number of major plants (> 1% of reads) in honey samples was 9 and 11 in ACH and AMH respectively indicating the higher diversity of plant taxa in AMH. 23 taxonomic units were found exclusively in ACH, 18 taxonomic units were found only in AMH and 15 taxonomic units were shared between ACH and AMH indicating that 73% of the taxonomic units were present only in honey originated from one of the honeybee species. Qualitative and quantitative analyses of the shared major plants revealed the division of floral resource between these co-existing honey bee species pointing to a low level of interspecific competition between these two important pollinators.