Analysis of pollen collected by honey bees, Apis mellifera, in developed areas

Honey bee (Apis mellifera L.) colony maintenance depends on foraging workers to obtain nutrients from flower and water sources year round. The floral diversity encountered by honey bee foragers in urban settings may be different than the diversity found in natural, more rural areas. Furthermore, honey bee colonies in urban settings may be exposed to pesticides and other chemicals applied in gardens, parks, and other urban surroundings through the pollen and nectar that foragers bring back to their hives. In this ongoing study we aim to identify the floral sources foraged by honey bees in urban areas.  We are doing so by collecting pollen and nectar samples once a month from 12-15 different urban sites per state in California, Florida, Michigan, and Texas. Floral identity and abundance from each site is identified by analyzing pollen subsamples that are homogenized and processed using standard acetolysis procedures. Samples are then identified to family, genus, or species level using light microscopy. Relative abundance of each pollen type is also measured. Our preliminary results from July 2014 pollen samples indicate that honey bees in urban settings primarily forage from a few preferred pollen sources at a given time period.