Calum

• - Shake the bees from a central frame in the super onto plastic sheeting
• - Fill approx 30g bees (that is about 300) into a labelled container
• - After killing the bees by freezing them weigh the sample of bees
• - Let the bees soak for at least 15 minutes in soapy water (use washing up liquid) and shake thoroughly.
• - Separate the varroa from the bees buy rinsing through a double sieve. Or use a course metal mesh (too catch the bees) over a coffee filter paper
• - count the varroa / 10g bees – this is equal to the % of bees in the colony afflicted
• - Calculation: Varroa / bee weight * 10 = varroa / 10g bees
• - Because 100 bees weigh 10g that equals the % of varroa infestation (do black bees weigh as much?)
• - Interpretation of result – this depends on the amount of brood the colony has and the time of year. If in July a varroa infestation of 1% is observed then the colony must be treated in the following weeks so that the colony has enough time to make healthy winter bees. After the colonies have stopped rearing in Oct/ Nov the Varroa infestation should be under 2%. Otherwise a winter treatment is imperative.
• or when 10 or more are falling per day (be sure ants and earwigs are not clearing them off you inspection board) or when your drone brood looks the attached picture below
• or when you see bees with deformend wings