U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 Carl Hayden Bee Research Center: Tucson, AZ
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    Careers


        


                    Information
                        Africanized Honey Bees
                                    Bee Safety
                                    Online Books
                                    Other NewsSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Pacific West Area Tucson, Arizona Carl Hayden Bee Research Center Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications
- Cold Storage Overview
- Why put colonies in cold storage to overwinter?
- When to put colonies in cold storage?
- Which colonies to put into cold storage?
- Cold Storage Overwintering Tool
- Overview
- Objective 1: Climate effects on bloom and floral rewards
- Objective 2. Landscape level nutrition models
- Objective 3: Determine pollinator number, diversity and pathogen load
- Objective 4: Develop a management plan for overwintering colonies in cold storage
- Outcomes
- Varroa Overview
- Varroa mite life cycle and reproduction
- Varroosis
- How to Monitor, Sample, and Treat for Varroa
- Current Research: Mite Migration
- Introduction
- BEEPOP+ Model

Title:   Author  item
                                            DeGrandi-Hoffman, Gloriaitem
                                            AHUMADA, FABIANA - Agscience Llcitem
                                            Zazueta, Victoritem
                                            Chambers, Monaitem
                                            Hidalgo, Geoffreyitem
                                            Watkins De Jong, Emily
  Submitted to: Experimental and Applied Acarology
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 2/18/2016
                                    Publication  Date: 2/24/2016
                                    Citation: Hoffman, G.D., Ahumada, F., Zazueta, V.E., Chambers, M.L., Hidalgo, G., Watkins De Jong, E.E. 2016. Population growth of Varroa destructor (Acari: Varroidae) in honey bee colonies is affected by the number of foragers with mites. Experimental and Applied Acarology. doi: 10.1007/s10493-016-0022-9.Interpretive Summary: Varroa mites are a serious pest of honey bees and the leading cause of colony losses. Varroa have relatively low rates of reproduction so it should take more than a year before mite populations are large enough to cause colony losses. However, this often is not the case. There are indications that factors other than reproduction might be causing unexpectedly high mite numbers in colonies. One factor might be that Varroa enter colonies on foragers drifting from other hives. We measured the proportion of foragers carrying mites on their bodies while entering and leaving hives, and determined its relationship to the growth of Varroa populations in those hives at two apiary sites. We also compared our estimates of mite population growth with predictions from a Varroa population dynamics model that bases mite population growth on mite reproduction. We found that mite populations in brood cells and on adult bees were low until September when there was a sharp increase especially at site 1. The frequency of foragers entering and leaving colonies with mites on their bodies also increased in the fall. We captured more foragers with mites at site 1 than site 2, and site 1 had larger mite populations in colonies.  The growth of mite populations was significantly related to the total number of foragers with mites (entering and leaving the colony). The proportion of brood cells where mites successfully reproduced was not significantly related to the growth of the Varroa population at either site. The model accurately estimated mite population sizes until November when prediction were much lower than those measured in colonies. These results provide evidence that growth of mite populations might not be due to reproduction alone, and that foragers carrying mites and entering hives might be contributing significantly to colony mite populations especially in the fall.
                                Technical Abstract: Varroa mites are a serious pest of honey bees and the leading cause of colony losses. Varroa have relatively low reproductive rates, so populations should not increase rapidly, but often they do. Other factors might contribute to the growth of Varroa populations including mite migration into colonies on foragers from other hives. We measured the proportion of foragers carrying mites on their bodies while entering and leaving hives, and determined its relationship to the growth of Varroa populations in those hives at two apiary sites. We also compared the estimates of mite population growth with predictions from a Varroa population dynamics model that generates estimates of mite population growth based on mite reproduction. Mite populations in brood cells and on adult bees remained low through the summer but increased sharply in the fall especially at site 1. The frequency of capturing foragers with mites on their bodies while entering or leaving hives also increased in the fall. The growth of Varroa populations at both sites was not significantly related to our colony estimates of mite reproduction, but instead to the total number of foragers with mites (entering and leaving the colony).  There were more foragers with mites at site 1 than site 2, and mite populations at site 1 were larger especially in the fall. The model accurately estimated phoretic mite populations and infested brood cells until November when predictions were much lower than those measured in colonies. The rapid growth of mite populations particularly in the fall being a product mite migration rather than mite reproduction alone is discussed.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov