Best Management Practices for Varroa Control
Controlling pests, particularly Varroa, is a critically important management practice.
Why is Varroa harmful to Honey Bees?
Varroa mites reduce individual bee and colony vigor by feeding on their haemolymph. In addition, they vector viruses and facilitate infection by other bee pathogens.
Manage for Varroa Control
- Varroa control should be a primary activity in your beekeeping operation.
- Requeen with mite resistant stock. Using stock selected for resistance may aid in slowing down the growth of Varroa populations.
Do your colonies have Varroa mites?
- Monitoring is important, early detection is key
- Check often, every 2-3 months
- Conduct a random sampling of hives
- Follow regional guidelines for action thresholds.
How to check for Varroa
- Sticky Boards for an accurate mite count
- Alcohol Wash
- Sugar/Ether Roll
How to treat for Varroa
- Use biotechnical methods to suppress mite populations if action is necessary when surplus honey is being produced.
- Drone brood removal
- Powdered sugar dusting
- Screened bottom boards
- If honey is being produced, use thymol-based materials or organic acids.
- Exercise judicious treatment and soft chemicals.
- Follow recommended label instructions.
- Rotate treatments to prevent resistance.
- Varroa mites have exhibited resistance to some varroacides in some regions. Check with your local cooperative extension office or apiary inspector to find out which varroacides are most effective in your area.
- Be aware that strong colonies in mid-summer can be highly infested with Varroa and even strong colonies can crash in population in late-summer and fall.
Are your treatments working?
- Recheck for efficacy; don't assume your treatments are working.
- Varroa is a community problem. Work with your beekeeper neighbors to be sure that all beekeepers are keeping Varroa at low levels.
Minimize toxin exposure
- Honey bees have a limited capacity to metabolize toxins, including beekeeper-applied varroacides, and some toxins can accumulate in beeswax combs.
- Be aware of crop pest control practices near your apiary; know the risks and have a plan for protecting colonies.
- Varroacides can tie up bees' detoxification capabilities and render them less able to deal with other varroacides and chemicals used on crops.
- Avoid treating bees with varroacides when they are likely to be exposed to crop pest control chemicals.
- Renew beeswax combs by replacing a few combs from each hive annually.
The Beekeeper's Goal
- A good management program pays close attention to mite levels.
- Varroa can rebound quickly; watch your threshold levels closely.
- Constant monitoring and timely treatment is critical for healthy hives.