An Integrated Approach to Controlling Varroa
There is now plenty of evidence that resistance to Bayvarol™ and Apistan™ has reached Buckinghamshire. Many failures of control were reported last year and we must now rely on other methods of controlling Varroa mites. By using a combination of treatments at the right time of year, very effective control can be achieved.
Our Regional Bee Inspector, Ian Homer, has given us permission to reproduce here the notes and worksheets he uses in his workshops on Varroa Control using Integrated Pest Management. There are a number of worksheets which describe each of the techniques in detail. The worksheets can be downloaded as ‘PDF’ files, click the mouse over the the worksheet numbers in the table below to view the documents.
What are we aiming for?
|An integrated strategy is guided by three principles:
- Methods used should aim to control mite levels, not eradicate them.
- Mite levels below the treatment threshold should not be controlled.
- Chemical treatments should be the last method used, not the first.
|How can we achieve this?
- Monitor mite levels regularly throughout the season
Worksheet No. 2 describes methods of measurement.
- Determine if treatment is needed
Worksheet No. 3 and Worksheet No. 4 give the treatment thresholds for each time of the year.
- Use one or more if these methods if treatment is indicated.
||Time of year
|Open Mesh Floors
||10% – 20%
||Worksheet No. 11
|Drone Brood Culling
||April to July
||Up to 50%
||Worksheet No. 14
||May to July
||Figures not available but considered to be very effective
||Worksheet No. 15
||Mid May to Mid July
||Up to 95%
||Worksheet No. 17
||Mid July to September
||74% to 99%, temperature dependent.
||Worksheet No. 13
|Bayvarol™ or Apistan™
||August to October
||Now less effective due to the build up of resistance
Defra has produced an excellent booklet on “Managing Varroa”. There is also a short best practice factsheet available that summarises a management approach to Varroa.