Improving Honey Bee Health and Crop Visitation during Pollination

Project Overview

Project Type: Research Only
Funds awarded in 2019: $148,827.00
Projected End Date: 06/30/2021
Grant Recipient: University of Maryland, College Park
Region: Northeast
State: Maryland
Project Leader:
Kirsten Traynor
University of Maryland
Dennis vanEngelsdorp
University Maryland


  • Fruits: berries (blueberries)
  • Animals: bees


  • Animal Production: animal protection and health
  • Crop Production: beekeeping, pollination, pollinator health

    Proposal abstract:

    1) Problem, Novel Approach and Justification.
    In the Northeast growers pay $16.45 million for pollination of 230,000+ acres of crops. Fees escalated due to declines in colony health and beekeeper concern over pesticide exposure. Certain crops like blueberries (32,500 acres) and cranberries (29,500 acres) pose a significant risk of pesticide exposure and are linked to colony loss. Honey bee colonies experience dwindling, inexplicable queen turnover events, and colony collapses during pollination. Preliminary experiments suggest pesticide contaminated pollen underlies these issues. Colonies fed fungicide contaminated pollen experienced excessive queen events and engaged in behavior that would confound typical management by experienced beekeepers. The pesticide exposed colonies also experienced reduced honey stores, nutritional stress and cannibalized their young compared to controls. Based on our initial results, we propose 1) stimulative feeding and 2) pollen trapping as a novel approach to improve colony health. We would like to further expand our proposal to test if colonies can be 3) induced to perform “precision pollination” through scenting their feed with crop odors to increase pollination of target crops.

    2) Hypothesis and Research Plan.
    Fungicide contaminated pollen led to increased queen events, while pesticide exposure led to nutritional stress. Treatment colonies prepared to swarm, even when typical swarm pressures were non-existent. Such swarm indicators induce beekeeper management strategies like splitting a colony, which increase nutritional stress and worsen colony outcomes. We propose that contaminated pollen leads to reduced nectar stores, nutritional stress and brood cannibalism in honey bee colonies during crop pollination, resulting in atypical queen replacement that looks like swarming, but isn’t. Our hypothesis is that trapping contaminated pollen via pollen traps and supplementing colonies with food resources reduces queen events and nutritional stress, leading to healthier colonies. We propose to run a multifactorial experimental design testing the impacts of pollen trapping and supplemental feeding on colony health. In Year 2, some colonies will have the sucrose spiked with crop scents to encourage targeted crop pollination. Additionally, we will repeat our preliminary experiment where we exposed colonies to contaminated pollen and monitor queen events and brood development. We previously ran full size colonies and will repeat in miniature colonies, so we can monitor queen events and brood cannibalism with greater precision.

    3) Outreach Plan.
    We will present results at the national honey bee research conferences with 200-500+ attendees. Regardless of effectiveness in reducing colony losses, we will publish an article in the industry trade magazine to publicize results with readership of 15,000 beekeepers. We will create factsheets for berry growers. 4) Project Objective. Improve honey bee health during pollination. Preliminary experiments indicate colonies experience nutritional stress and reject healthy queens when exposed to fungicides; we seek to ameliorate this through feeding and pollen trapping to reduce pesticide contamination during crop pollination.

    Project objectives from proposal:

    Our objective is to improve honey bee health during pollination. Our novel approach ameliorates pesticide exposure and potentially increases pollen foraging on target crops, ensuring a steady pollination supply for blueberry and cranberry growers. This novel approach provides beekeepers with inexpensive protection and if “precision pollination” training is effective, significantly improves pollination of target crops, an important innovation as bees notoriously stray from blueberry and cranberry fields to more appealing resources within flight range.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.