Source: CORNELL UNIVERSITY submitted to
EVALUATION OF SMALL-CELL COMBS FOR CONTROL OF VARROA MITES IN NEW YORK HONEY BEES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0211868
Grant No.
(N/A)
Project No.
NYC-191419
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Oct 1, 2007
Project End Date
Sep 30, 2010
Grant Year
(N/A)
Project Director
Seeley, T. D.
Recipient Organization
CORNELL UNIVERSITY
(N/A)
ITHACA,NY 14853
Performing Department
NEUROBIOLOGY AND BEHAVIOR
Non Technical Summary
The mite Varroa destructor poses the largest threat worldwide to honey bees. This project will evaluate the effectiveness of small-cell combs for the control of Varroa in New York State.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
31230101130100%
Goals / Objectives
1) To establish an apiary of 20 genetically homogeneous colonies of European honey bees that are housed in hives with either standard-cell combs or small-cell combs, and that are infested with the parasitic mite Varroa destructor. 2) To compare the population dynamics of the mites in the two treatment groups, to see if giving colonies combs with small cells results in effective control of the Varroa mites. 3) To compare the patterns of colony growth and honey production in the two treatment groups, to see if giving colonies combs with small cells hampers their growth and productivity.
Project Methods
In year 1, we will prepare 20 hive bodies with frames of small-cell (4.9 mm) combs and 20 hive bodies with frames of standard-cell (5.4 mm) combs. All combs will be built by providing colonies with honey supers filled with frames of either small-cell or standard-cell foundation. The bees will build these combs while filling them with honey. At the end of the summer, we will extract the honey from these combs so that they can serve as brood combs the following summer. We will also establish 12 source colonies to provide bees the following summer; each colony will be headed by a new Italian queen bee. These queens will be sisters, to minimize genetic differences among colonies. In year 2, we will select the 10 strongest source colonies and will prepare from each colony two equal-size artificial swarms. Each swarm will be given a new Italian queen (queens will be sisters). Because both swarms in a pair will come from the same colony, they will have equal infestations of Varroa mites. In each pair of swarms, we will give one swarm a hive (two hive bodies) with small-cell combs and the other swarm a hive with standard-cell combs. Each month thereafter, we will measure for each colony the number of cells containing brood, the mite infestation level (measured by counting the mite drop per 48 h), and the weight (honey) gain. Using a paired-comparisons statistical analysis, we will test for differences between the two treatments in brood population, mite infestation, and honey production. In year 3, we will continue making the monthly measurements and comparisons between the two treatments.

Progress 10/01/07 to 09/30/10

Outputs
OUTPUTS: Over the three-year period of this study, the PI, Thomas D. Seeley, made 15 presentations of the findings related to the grant at meetings of beekeeper associations. The venues included the Southern Adirondacks Beekeepers Association, the Ohio Beekeepers Association, the New Jersey Beekeepers Association, the British Bee Keepers Association, the Yorkshire Beekeepers (England), the Somerset Beekeepers (England), the Meridian Beekeepers (England), the Maine Beekeepers Association, the Massachusetts Beekeepers Association, the Backyard Beekeepers Association, The Eastern Apicultural Society, the Georgia State Beekeepers Association, the Virginia State Beekeepers Association, the Chester County Beekeepers Association, and the Maryland Beekeepers Association. Each summer, Dr. Seeley mentored a Cornell undergraduate who participated in the project, and during the 2009-2010 academic year he worked with one of these students, Sean R. Griffin in the preparation of the manuscript that reports the results of the grant. PARTICIPANTS: The research work on this project was performed by the PI (Thomas Seeley) and one Cornell undergraduate student each summer (Madeleine Girard, Sean Griffin, and John Chu). TARGET AUDIENCES: There are two target audiences. For the basic knowledge about the effects on the population dynamics of Varroa mites of altering cell size in honey bee combs, the target audience is all researchers on the biology of honey bees. For the applied knowledge about beekeeping that this research is generating, the target audience is beekeepers worldwide. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
The work supported by the grant has now shown conclusively that providing honey bee colonies with frames of small-cell (4.9 mm) combs does not depress the reproduction of Varroa mites relative to giving colonies frames of standard-cell (5.4 mm) combs. These results from New York State match those of two other investigations on this topic that were conducted independently and in parallel in two southern states, Georgia and Florida. It seems clear, therefore, that despite much interest by and discussion among beekeepers in using small-cell combs to control Varroa mites without chemicals, this approach is completely ineffective. The research work supported by this grant is about to appear in a leading peer-reviewed scientific journal (Apidologie) and once this formal publication appears the PI will publish a companion report written for beekeepers in a popular beekeeping magazine (Bee Culture).

Publications

  • Seeley, T.D. and S.R. Griffin. 2011. Small-cell comb does not control Varroa mites in colonies of honey bees of European origin. Apidologie. In press.


Progress 10/01/08 to 09/30/09

Outputs
OUTPUTS: Senior personnel: Dr. Thomas D. Seeley made 8 presentations of findings related to the grant at scientific conferences and beekeeper association meetings, and was invited to speak about the research findings at several universities and colleges. These venues included: 1 presentation at a regional scientific workshop (SUNY Conversations in the Disciplines), 1 invited presentation at a monthly meeting of the Backyard Beekeepers Association, 2 invited presentations at the annual meeting of the Eastern Apicultural Association, 2 presentations as an invited seminar speaker at the annual fall meeting of the Georgia State Beekeepers Association, and 2 presentations as an invited seminar speaker at the annual fall meeting of the Virginia State Beekeepers Association. Dr. Seeley continued to mentor a Cornell undergraduate who participated in the project throughout the Summer of 2009, and guided him in the preparation of a manuscript regarding another study that was not part of the grant. PARTICIPANTS: The research work on this project was performed by the PI (Thomas Seeley) and one undergraduate student (Sean Griffin). TARGET AUDIENCES: There are two target audiences. For the basic knowledge about the effects on the population dynamics of Varroa mites of altering cell size in honey bee combs, the target audience is all researchers on the biology of honey bees. For the applied knowledge about beekeeping that this research is generating, the target audience is beekeepers worldwide. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
The work supported by the grant has now shown conclusively that providing honey bee colonies with frames of small-cell (4.9 mm) combs does not depress the reproduction of Varroa mites relative to giving colonies frames of standard-cell (5.4 mm) combs. These results match those of parallel investigations on this topic that were conducted independently in Georgia and Florida. It seems clear, therefore, that despite much interest by and discussion among beekeepers in using small-cell combs to control the nites without chemical, this approach is ineffective. The studies that have been supported by this grant will be reported through a publication in a peer-reviewed scientific journal (Apidologie) and a beekeepers' magazine (Bee Culture).

Publications

  • No publications reported this period


Progress 10/01/07 to 09/30/08

Outputs
OUTPUTS: The principal output over the past year has been an Activity: developing further the methods for getting the bees to build combs with small cells (4.9 mm diameter), rather than their normal size cells (5.4 mm diameter). The key experiment of this study calls for setting up paired colonies, with one colony in each pair living on combs of small cells and the other colony living on combs of normal cells, then comparing the two types of colonies in terms of the growth of their populations of the mite Varroa destructor. I have tried various methods for getting bees to build small-cell combs but have not yet found a method that results in combs filled with small cells. Instead, I get combs that are a weird mixture of small cells and quite large cells. So, despite my best efforts over the past two summers, I have not yet performed the key experiment. Given that I have just one more summer of support in this project, I will perform the key experiment next summer using combs of small cells that are made of plastic and that are commercially available. Doing the experiment this way is not ideal, for these combs are too expensive for general use by beekeepers, but using them will enable me to test the still untested (but widely believed) hypothesis that small-cell combs lower the population growth rate of the Varroa mites in a honeybee colony. We shall see! PARTICIPANTS: There have been two participants: myself, and a Cornell undergraduate student, who has worked as the research assistant. TARGET AUDIENCES: The target audience for this project is ALL beekeepers in North America and Europe, i.e. all beekeepers who work with the European subspecies of the honey bee and whose colonies are infested with the parasitic mite Varroa destructor. PROJECT MODIFICATIONS: As indicated above in the Outputs and Outcomes, I need to stop trying to conduct the experiment using combs of small cells built by the bees (my bees won't build combs filled with these diminutive cells), and need to conduct the experiment using combs of small cells built of plastic. Although my bees won't give me the combs I need for this experiment, a human manufacturer will!

Impacts
The principal outcome over the past year has been a Change in Knowledge. Specifically, I have learned just how difficult it is to get honeybees to build combs made of smaller than usual cells. This is an important finding, because beekeepers are being encouraged to have their bees build combs with small cells as a means of controlling the mite Varroa destructor, and beeswas comb foundation is being sold to guide the bees to build these combs, but at this point no way has been found to get bees to reliably construct combs of small cells. I now know that I cannot recommend this approach to Varroa control. There has also been a Change in Action. Because I've not succeeded in getting my bees to build combs filled with small cells, I've decided next summer to perform the key experiment of this project (setting up paired colonies, with one colony in each pair living on combs of small cells and the other colony living on combs of normal cells, then comparing the two types of colonies in terms of the growth of their populations of the mite Varroa destructor) using combs of small cells manufactured of plastic, rather than built by the bees of beeswax. This will at least enable me to test the critical hyptothesis: a colony living on small-cell combs will have a lower population growth rate of the Varroa mites than will a colony living on regular-cell combs..

Publications

  • No publications reported this period