Research Project: Managing Honey Bees Against Disease and Colony Stress

Location: Bee Research Laboratory

2025 Annual Report

Objectives
The overarching goal of the project is to develop management strategies for bee diseases & colony health & to provide the beekeeping community with advice for best practices to build & maintain healthy bee populations for pollination. This goal will be achieved by pursuring the following specific objectives: OBJ 1: Develop diagnostic & data management tools for use in mitigating the effects of current & emerging honey bee diseases & pests & continue to operate the Agency’s Bee Disease Diagnostic Service. [NP305, Component 2, PS 2A & 2B] 1.A: Identify & characterize new & emerging pathogens that cause honey bee diseases & to develop efficient diagnostic markers to monitor disease onset & progression in honey colonies; 1.B: Develop diagnostic method for measuring stress in honey bees; 1.C: Improve diagnostic & informatic tools for bee health. OBJ 2: Develop novel & effective treatment solutions, including varroacides & natural products, that reduce the incidence & prevalence of bee diseases & disorders to help beekeepers maximize pollination services & honey production. [NP305, Component 2, PS 2A & 2B] 2.A: Develop tools & strategies for preventing & controlling honey bee pests that harm individual bees & damage hive products; 2.B: Develop RNAi based specific therapeutics for bee diseases; 2.C: Identify natural products that reduce bee diseases; 2.D: Develop novel methods to mitigate the detrimental effects associated with pesticide exposure. OBJ 3: Analyze the seasonal behavior & physiology of adult worker bees, & thus develop improved best management strategies for increasing the overwintering success of honey bee colonies in the field. [NP305, Component 2, PS 2A & 2B] 3.A: Refine our understanding of the seasonality of honey bee colonies & identify abiotic & biotic factors that disrupt the timing or occurrence of seasonal events; 3.B: Determine overwintering strategies of honey bee pests, including Varroa mites, wax moths, & small hive beetles, & develop methods & tools for their control; 3.C: Determine the effects to biological clock/seasonal physiology of honey bees from different overwintering strategies employed by beekeepers & develop successful overwintering strategies. OBJ 4: Determine the causes of queen failures & improve honey bee queen quality related to colony survivorship. [NP305, Component 2, PS 2A & 2B] 4.A: Improving queen genetic diversity & their resistance to diseases; 4.B: Compare available queen lines & stocks to determine their disease Resistance; 4.C: Define the epigenetic factors of queen fitness & develop strategies to improve queen quality. OBJ 5: Analyze the interactions between honey bee nutrition, their microbiomes, chemical stress, disease, & hive treatments, to improve bee health & performance. [NP305, Component 2, PS 2A & 2B] 5.A: Determine the effect of nutritional supplementation on honey bee behavioral development & disease immunity; 5.B: Determine the relationship between gut microbiota & nutrition on honey bee behavior & immunity to diseases & abiotic stressors; 5.C: Improve bee defenses in the face of abiotic & biotic stress.

Approach
Bee Research Laboratory scientists combine laboratory and field approaches and integrate physiology, molecular biology, toxicology, ecology, and multi-omics technologies (genome, metagenome, transcriptome, epigenome, metabolome, and microbiome) into an interdisciplinary research program to generate new knowledge, technologies, and tools for 1) diagnosing, treating, and mitigating bee diseases and pests, 2) creating platforms that provide data sources and analytic applications to advance bee research and to broaden the range of our custom services, 3) improving colonies' overwintering success, 4) developing strategies for improving queen quality, and 5) discovering nutrition-based approaches for disease prevention and health promotion and protecting bees from pesticides and other toxins present in the environment. BRL scientists work with industry leaders and stakeholders to help license and develop products that will be useful for beekeepers and customers.

Progress Report
This is the final report for this project which terminated in February 2025. Research across this project lifespan produced over 100 publications and seven invention disclosures covering each of the stated Objectives. Key advances made for project Objective 1 (Develop improved diagnostic, delivery systems and genetic resources including the deployment of genomic tools, to monitor and mitigate key threats to honey bees and other pollinators) include state-by-state and national publications documenting disease samples collected from all 50 states across nearly 40 years. This analysis has driven new diagnostics and efforts to identify the causes of colony losses. Genomic characterization helped facilitate future monitoring of honey bee parasites and the development of gene-based controls. For Objective 2 (Provide novel management solutions to reduce the impacts of mites and other bee diseases and disorders, maximizing pollination services and honey production), significant progress was made in Subobjective 2.A (Develop novel mite treatments to improve colony health). Nearly 40 active compounds and several biocontrol agents were tested in the laboratory and field and one of these is in the regulatory process. For Subobjective 2.B (Develop natural products as honey bee medicines), a total of 235 compounds and extracts were tested in newly developed lab bioassays, resulting in nine that were tested in field colonies and one successful patent. For Subobjective 2.C (Develop AI and gene-based immune and disease treatments), 90 compounds predicted by AI to bind to a key enzyme of Deformed wing virus, a major health threat of honey bees, led to four lead compounds with potential for further development. For Objective 3 (Improve honey bee health, performance and overwintering success through mitigating interactions between nutrition, microbes, chemical stress, physiology, seasonal behavior, and diseases), amino-acid supplements were shown to have effects on disease levels in bee colonies. Certain amino-acid mixes, while they improved bee physiology, also led to higher parasitism. In addition, monthly disease and colony health surveys showed that colonies were surprisingly active in winter, arguably making them more vulnerable to parasitic mites. Identified disease agents and genetic responses by bees led to management programs to reduce overwinter losses. Collectively, research under this program improved the management of honey bees against disease and colony stresses by identifying key causes of colony losses and developing medicines and management tools to help reduce those losses. These efforts were funded by base funds, interagency transfers, stakeholder grants and governmental grants. See the report for the replacement project, 8042-30500-002-000D, "Mitigating Disease and Stress in Honey Bee Colonies" for additional information for continued impacts from the Objectives for this Plan.

Accomplishments