7 concepts
Frequency of pollinator visits to flowers measured as visits per individual per minute or visits per flower per minute
The total number of flowers available as nectar and pollen resources measured as flowers per meter
Availability of flowering plants that provide pollen and nectar for bee reproduction, quantified as floral density in standardized plots
Diet breadth of bees classified as oligolectic (collect pollen from flowers in multiple plant families) or polylectic (collect pollen from flowers in just one family)
The length of flower tubes, which correlates with bumble bee proboscis length and determines flower accessibility
The energetic cost of provisioning brood cells, measured by number of foraging flights per completed cell and provision mass