Mite-biting behavior in feral swarms: The Pennsylvania Queen Improvement Project

Project Overview

Project Type: Farmer
Funds awarded in 2017: $15,000.00
Projected End Date: 12/31/2018
Grant Recipient: Always Summer Herbs, LLC
Region: Northeast
State: Pennsylvania
Project Leader:
Jeffrey Berta
Always Summer Herbs


Not commodity specific


  • Animal Production: animal protection and health
  • Crop Production: beekeeping
  • Education and Training: farmer to farmer

    Proposal summary:

    Varroa mites are the single greatest threat to sustainable beekeeping in the Northeastern US, and
    across the world. Now, a new novel genetic trait described by Dr. Greg Hunt from Purdue
    University (SARE LNC08-295 2008-2011) is Mite-Biting Behavior (MBB). The MBB trait is when
    the honeybees bite off one or more legs from a varroa mite; bitten mites will then bleed to death.
    Further field work was conducted in a 2015 SARE (FNE15-819) grant which measured the
    relationship of MBB to the total mite count, an unexpected discovery was made, we found
    non-Purdue bees were also chewing mites. Future recommendations were made to further
    investigate these isolated and distinct Mite-biting populations of bees.

    We will use swarm traps to capture feral swarms in locations were there are no commercial bees
    nearby. Traps will be removed, weighed, and then measured for MBB, mite count, and Winter
    Survivorship. If MBB can increase winter survival, it will increase the sustainability by reducing
    replacement costs of dead bees. We want to determine if and why feral colonies are more winter
    hardy than our currently available bees, and if MBB plays a role, or perhaps some other trait.
    This project will involve queen breeders, beekeepers in three states, and two universities and their
    extension services. Feral colonies have survived winter for years without human intervention and
    mite treatment; these would be genetic treasure for the future of breeding mite resistant bees.

    Project objectives from proposal:

    Several studies have been performed regarding the interrelated, and complex reasons for
    overwintering losses, Colony Collapse Disorder (CCD) and Parasitic Mite Syndrome (PMS) in
    honeybee colonies. Most notably Dr. Marla Spivak from the University of Minnesota made
    significant and groundbreaking improvements in breeding of bees with a trait commonly referred to
    as hygienic behavior. Briefly, hygienic behavior is when bees remove parasite-infested bee pupae
    from the brood nest before either the pupae or parasite reaches maturity. USDA scientists Harbo
    and Harris identified a second trait that reduced mite levels termed suppress mite reproduction
    (SMR), which was also used to select for Varroa resistant stocks. Subsequently, this behavior has
    been better defined as “varroa sensitive hygiene” (VSH), which functions similarly to hygienic
    behavior. Now, a new novel genetic trait described by Dr. Greg Hunt (SARE LNC08-295
    2008-2011) is Mite-Biting Behavior, the MBB trait is when the honeybees bite off one or more legs
    from a varroa mite, and bitten mites will then bleed to death. Dr. Hunt also saw promising
    preliminary results in a comparison of MBB and a control group in his 2014 National Honey Board
    paper. Overwintering success was positively correlated colony weight more than any other
    measured parameter (Doke et al, in preparation 2014-5 PSU). These findings lead to measuring:
    MBB, colony weight, and overwintering success. Swarm capture and genetic distinction of feral
    colonies has been described by Tom Seeley (2010), and we will employ his swarm traps and
    methods. It is important to note, that there have been several SARE grants that involved swarm
    capture, but none have ever measured mites, MBB, or winter hardiness.

    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.