Dataset: Plant and bee transects in the Northern Great Plains 2015-2018

These data were collected to fulfill multiple Inter-agency agreements established by USGS and multiple partners: USDA Farm Service Agency, USDA Natural Resources Conservation Service, and the Honey Bee Health Coalition. In this study USGS scientists conducted floral resource and insect pollinator assessments across multiple land covers in North Dakota, South Dakota, and Minnesota from 2015 to 2018. Sampling was done along 2x20m transects in June through September by a single observer. All transects were located on private or public grasslands such as Conservation Reserve Program (CRP) lands, Environmental Quality Incentives Program (EQIP) lands, managed pasture, haylands, roadside ditches, Waterfowl Production Areas (WPA), National Wildlife Refuges (NWR), and Wildlife Management Areas (WMA). Transect locations were randomly selected in a Geographic Information System and all transects were >10 m from each other. Each 20x2m transect was surveyed during three time periods (08 June-15 July, 16 July- 15 Aug, 16 Aug-15 Sept) by a single observer who quantified floral resources and noted observations of honey bees and wild bees on specific flowers within the transect boundary. Transect boundaries were delineated with a meter tape laid along the center line and metal flags at the four corners. At each transect, observers counted the number of basal stems that supported one or more inflorescences, which served as our index of flower abundance (hereafter referred to as flower abundance). Flowering plants were identified to species in most cases. During flower counts, observers recorded observations of wild bees and honey bees collecting nectar or pollen from specific flowers. Bees flying through the transect, but not landing on a flower, were not recorded. At a subset of transects, starting in 2016, individual native bees were netted while visiting flowers. Captured native bees were euthanized and brought to Northern Prairie Wildlife Research Center for identification.