If you haven’t already started, now is the time to get your mite monitoring program underway for the season. With the big effort of getting your bees installed (if you’re a new beekeeper) or getting them safely past swarm season and supered up (if you overwintered them), it’s easy to postpone monitoring. But that would be a mistake.
You need to know what your mite levels are now, and going forward, in order to plan ahead for any summer treatments that may be needed. For most beekeepers, summertime is when they have honey supers on their hives. Many mite treatments can’t be used when you’re collecting honey, and some have temperature limitations for safe use. With these restrictions in mind, you need as much advance warning as you can get.
If you begin monitoring well before you may need to treat, you will build a data set. This will allow you to foresee and take advantage of the best opportunity to get the mites suppressed before they can do too much damage later in the season. Without a monitoring program, you are forced treat “by the calendar” which may not be the most effective. And in some years, it may even result in over-treatment.
Simply put, a good monitoring program is one that gives you the information needed to be able to predict when you’re likely to need to take action. This will keep the mites below the level where your bees would be substantially harmed. Any single test (using any of the methods) is much less valuable than the information gathered from a series of tests over time.
That depends on the kind of test you choose. If you are using mite monitoring boards, then weekly counts over a 72-hour period will give you the most clear results. If you want to do alcohol washes or sugar rolls, then monthly counts on each hive (or a sampling within a yard, if it is large) is what you should do.
The best method is something you will do, faithfully, throughout the season.
Many beginners, if they have screened bottom boards, start out using mite monitoring surfaces (also called sticky boards). This is an easy, non-intrusive, method. Done every week, this type of count will alert you to the steady increase of mite levels over the summer. Mite monitoring boards give you an estimate on the overall level of mites in the colony.
Beekeepers with a little more experience handling frames of bees often switch over to doing sugar rolls or alcohol washes in order to get a fix on the mite levels on the nurse bees in the hive. Testing the nurse bees gives a clearer picture of the infestation level, because of all the bees in the hive, nurse bees are in closest proximity to the mites. Both rolls and washes are done monthly on each colony, often rotating through the colonies, doing a few each week.
Here’s how to use a mite monitoring board and an FAQ about using them.
Here’s how to do a sugar roll.
Here’s how to do an alcohol wash using the Varroa EasyCheck device.
Write the numbers down, so you can see the trend over time, because it is the cumulative data that will best predict where the mite numbers are headed. In the summer, they are generally going up, but you need to know the pace of increase in order to be able to decide how soon you may need to take action. If you'd like to have a printed form to record your mite numbers, this is a handy one from the Dyce Bee Lab at Cornell University in Ithaca, NY.
Some beekeepers do simply treat on a fixed schedule. But by doing so they may not be treating at the best time to get the best mite control. It may be too early, or too late, or even occasionally unnecessary. And human nature being what it is, it’s easy to get complacent and think things are OK, when they aren’t. Facing down your monthly (or weekly) mite counts will keep you focused on the problem, and perhaps more likely to do what’s needed to keep your bees healthy and thriving.