PS 48-248 - Comparison of Bee Foraging Behaviors Across Different Regions and Time Periods in Taiwan

Abstract: Bees significantly contribute to ecosystem services, as they can facilitate pollination between floral plants, promote the seed-setting rate, and even maintain biodiversity. However, few studies have compared the forage preference of different bees across spatial and temporal. In this study, we compared the foraging behaviors of Apis cerana Fabricius and A. mellifera Ligustica at Yadong Farm (YDF) and National Chiayi University (NCYU) in Taiwan. The pollen trap entrances were open for three to four hours between 5 am and 7 pm to collect the pollen. Pollen grains were dried and weighed before the taxonomical identification by the light microscope. We used Jaccard's similarity index and Bray-Curtis dissimilarity of pollen percentage data to estimate the similarity between bees and sites. We also used principal component analysis (PCA) and principal coordinates analysis (PCoA) to test the forage preference of bees.

Our results showed that A. mellifera collected more pollen grains regardless of the region than A. cerana. Both bee species were more active in the morning, while bees at NCYU were active earlier than YDF. The dominant pollen abundance exhibited a similar Jaccard's index between the two sites, whereas the Bray-Curtis dissimilarity of composition exhibited about 56% similarity. Both PCA and PCoA indicated pollen taxa association with the location, possibly due to differences in vegetation, blooming time, foraging preference, and interspecies competition. However, some pollen types could not be identified based on morphology, indicating a need for next-generation sequencing. Our study provides insight into the foraging preferences of A. cerana and A. mellifera in different regions and periods and may inform under-forest economic development in Taiwan.