Varroa destructor is  small innocuous looking mite that has spread throughout the world. It became one of the most infamous pests in recent beekeeping history. 

It is a parasite, and has been found on honey bee's and bumble bee species.

IBRA has published many articles on the subjest and in 2007 collected them together to produce Apicultural Research on Varroa   This book has been edited by one the world experts, Dr Stephen J Martin. 

We also have an information poster on Varroa.  Please go to our online shop for further details

Varroa! Fight the Mite

In response to demands by beekeepers for more information on how to control varroa, IBRA held a one-day meeting in Cardiff, UK, in October 1996, specifically aimed at meeting the needs of beekeepers, and to arm them to 'fight the mite'.

Problems of mite resistance to fluvalinate (Apistan) and flumethrin (Bayvarol), and residues in honey and beeswax have prompted beekeepers to look for alternative controls (as opposed to organophosphate and pyrethroid varroacides) such as organic acids e.g. formic acid, and essential oils e.g. thymol. However, not all these products are approved or licensed in some countries and so information about their use is not always readily available.

Another factor is the high cost of products such as Apistan and Bayvarol. 'Alternative' techniques are usually cheap, but may be more time consuming and, although labour costs are an important part of the equation for commercial beekeeping operations, for the hobby beekeeper this may not be an important issue.

Key points to come out of the conference

• Varroa is not a problem that will go away by itself. You are not doing your neighbouring beekeepers any favours by not dealing with infested colonies. Re-invasion of mites from robber bees from other infested colonies is a major problem, especially when varroa is first detected in an area, and so it is essential to monitor your hives regularly.
  
• Bees can usually suppress the effects of the viruses (e.g. sacbrood virus) that are normally found in colonies at low levels. It appears that varroa in some way stops this happening so that the viruses multiply to lethal levels resulting in sudden colony collapse - even in colonies treated with varroacides. 
  
• Mite resistance to fluvalinate/flumethrin has shown us that you can not rely on just one method of control, and minimizing the amount of chemicals used can only be good practice. However, organic controls are more labour intensive and efficacy can be variable, and so an integrated approach is needed. This might involve alternating between chemical and organic/biotechnical methods, or a combination of alternative controls such as formic acid and drone trapping. 
  
• Whatever method you decide is best for you, follow the manufacturer's instructions for the product and use the correct dose at the right time. Any chemical - be it 'natural' or otherwise - if misused can endanger the beekeeper and the bees, and give rise to residues in the wax and honey. Contaminated honey not only damages your reputation, but also the image of bee products as being pure and natural. 

Article by Pamela Munn

A book published by IBRA called Varroa! Fight the Mite, edited by Pamela Munn and Richard Jones, is now available from our online shop.