DOI: 10.5061/dryad.wh70rxwjz
title: Honey bees and wild pollinators differ in their preference for and use of introduced floral resources

description: Introduced plants may be important foraging resources for honey bees and
 wild pollinators, but how often and why pollinators visit introduced
 plants across an entire plant community is not well understood.
 Understanding the importance of introduced plants for pollinators could
 help guide management of these plants and conservation of pollinator
 habitat. We assessed how floral abundance and pollinator preference
 influence pollinator visitation rate and diversity on 30 introduced vs. 24
 native plants in central New York. Honey bees visited introduced and
 native plants at similar rates regardless of floral abundance. In
 contrast, as floral abundance increased, wild pollinator visitation rate
 decreased more strongly for introduced plants than native plants.
 Introduced plants as a group and native plants as group did not differ in
 bee diversity or preference, but honey bees and wild pollinators preferred
 different plant species. As a case study, we then focused on knapweed
 (Centaurea spp.), an introduced plant that was the most preferred plant by
 honey bees, and that beekeepers value as a late-summer foraging resource.
 We compared the extent to which honey bees vs. wild pollinators visited
 knapweed relative to co-flowering plants, and we quantified knapweed
 pollen and nectar collection by honey bees across 22 New York apiaries.
 Honey bees visited knapweed more frequently than co-flowering plants and
 at a similar rate as all wild pollinators combined. All apiaries contained
 knapweed pollen in nectar, 86% of apiaries contained knapweed pollen in
 bee bread, and knapweed was sometimes a main pollen or nectar source for
 honey bees in late summer. Our results suggest that because of diverging
 responses to floral abundance and preferences for different plants, honey
 bees and wild pollinators differ in their use of introduced plants.
 Depending on the plant and its abundance, removing an introduced plant may
 impact honey bees more than wild pollinators.
description: The dataset was collected in two phases.
 First, in 2017, data was collected on visitaiton rates and
 diversity of pollintors visiting plants in three meadows in upstate New
 York. Data was collected throughout the flowering period. Please see the
 publication for details on data collection. <br>
 Second,  in 2018, data was collected on knapweed pollen and nectar
 collection in 22 apiaries across New York. Each apiary was visited twice,
 nectar and pollen samples were taken from two hives per apiary. For each
 sample, we counted the number of knapweed pollen grains per 300 total
 grains in a subsample of the substrate (nectar or pollen). Also, in 2018,
 we collected insects visiting knapweed in 7 fields across New York. Please
 see the publication for details on data collection.
description: Please note that to preserve confidentiality, we have rounded the
 lat lons of apiaries to a tenth of a decimal place. Therefore, these data
 should NOT be used for any type of analysis that involves quantifying land
 use or land cover at the landscape scale.  I have
 included four metadata files (.rtfs) to describe the table attributes for
 the four datasets.