Development of a test design for a semi-field, colony feeding study for the common eastern bumble bee (Bombus impatiens [Hymenoptera:Apidae])

Ecological risk assessment is a key component of the regulatory process required for registration of crop protection products around the world. The western honey bee (Apis mellifera) is the model organism for pesticide risk assessments for bees, but there are uncertainties over whether it is predictive of risks to other bees. Consequently, efforts are underway to develop test methodologies for other non-Apis bees. We conducted a semi-field colony feeding study with Bombus impatiens colonies to develop a colony-level methodology for bumble bees. We exposed commercially available bumble bee colonies to diets consisting of four concentration treatments of dimethoate insecticide (0.05, 0.19, 0.75, and 3.0 mg a.i./L) via supplemental sugar solution for six weeks and compared exposed colonies to untreated controls. Each treatment group had 10 replicate colonies, with one replicate per treatment group represented at each of the 10 study rural locations. We collected data on various colony-leve...,
Test Material
We used pure PestanalTM dimethoate (Sigma Aldrich, St. Louis, MO; Lot # BCBS9338, purity ≥98%) as the test material.
Bumble Bee Colonies
On 16 June 2020, we obtained 80 Excel-type B. impatiens colonies from Koppert Biological Systems Inc. (Michigan, USA). Excel-type commercial colonies as described by the vendor contained a minimum of 70 worker-caste females and a queen nesting on a plastic foundation within a cardboard hive box. The plastic foundation has a hive entry of limited size that acts as a queen excluder, allowing the traffic of worker and drones, but not queens. Each hive was fitted a plexiglass observation lid and without any cover to the nest by request to the supplier. Bees were fed ad libitum with a sugar syrup solution and honey bee-collected pollen for one week. Upon receipt, the weight of each colony was measured. Sixty queenright study colonies were selected for field deployment by removing the most extreme by weight colonies, i.e., the lightest and hea..., , # Development of a test design for a semi-field, colony feeding study for the common eastern bumble bee (Bombus impatiens \[Hymenoptera:Apidae])

[https://doi.org/10.5061/dryad.wwpzgmssv](https://doi.org/10.5061/dryad.wwpzgmssv)

We have submitted our raw data (cfs.arrival.csv, Bayer.CFS.basic.information.csv, bayer.cfs.cca.2022.csv, bayer.cfs.2020.foraging.csv), treatment groups (bayer.cfs.trts.csv), locations/sites coordinates (Bayer_CFS_sites.csv), codes for land use from the National Land Cover Dataset (NLCD.codes.csv), and R script (bayer.CFS.2020.R).

**Descriptions**

cfs.arrival.csv - Contains the observations of 80 bumble bee (*Bombus impatiens*) commercial colonies at the time of receipt in the field facility and from which 60 colonies were selected for the study. The variables recorded were:

* Hive.no: Assigned number from 1 to 80, to identify the colony.
* Date: Date of observations
* Hive.mass: The mass (weight) of the commercial colony including the bumble bee nest, brood...