Monitoring Varroa Mite Levels

The views, opinions and recommendations expressed in this article are solely those of the author and do not necessarily reflect those of PerfectBee.

Happenings in the Bee Yard

This week I want to talk about Varroa Mite monitoring, specifically as it applies to my colonies.  But before we discuss the dreaded Varroa Mite and monitoring Varroa Mite levels, let’s talk about what happened in the bee yard this week.  And, as I promised, I have named the colonies and the queens.  I’ll retire the stronger hive, weaker hive, and new hive nomenclature after this week.  I think you’ll find my naming appropriately “creative”!

The New Hive – Aquitine

My newest hive, which was the focus of last weeks inspection, is doing well.  It is still light on workers.  To assist this hive and give it a jumpstart, I transferred a frame of brood and bees from my strongest hive into this hive.  That will give it a boost in the number of new workers soon as well as a jumpstart with foragers once the current nurse bees are ready to transition to foraging.

This small colony is growing.  In fact, the queen has been very active and is laying eggs regularly now.  The queen is establishing a very nice brood pattern with eggs and larvae in all stages of growth.  This hive contains my only marked queen.  If you remember, I had already named this marked queen when I established her in the nuc hive.

In honor of the queen, Eleanor, I will call this colony, “Hive Aquitaine”.

There are plenty of frames on which this colony has not drawn comb yet.  Since fewer than 8 or 10 frames have drawn comb, it will be a while before this colony is ready for a second deep box.  But, given the rate at which Eleanor is laying eggs, it will be likely that by the end of the month this colony will be ready for its second deep box for additional brood.

Only time and patience will tell the tale concerning this colony and how it will progress over the coming summer months.  While I was working this hive, I added some sugar water for the small amount they have used.  Hopefully that additional frame of brood and bees will augment their population and get them to more readily accept the sugar water.

The Weaker Hive – Olympus

Now that this weaker colony has a queen, she is kicking things into a higher gear.  She has been spending a lot of her time in the the second brood box and definitely has room for expansion down into the first brood box.

I may have to switch the position of the brood boxes to get her to move into the brood box containing plenty of empty cells, awaiting the next generation of workers.

If you remember, last week I was unable to get a clear picture of this queen.  I have to give credit to my best friend for taking all the pictures for this post.  I never tire of looking for this queen when I’m inspecting this colony.  She is the largest queen in my bee yard and by far the most beautiful in my opinion.

This colony has been busy drawing comb on the new frames I placed in the medium box last week.  They have deposited mostly honey made from the sugar water in the cells they have built.  The queen has filled at least two or three frames full of newly laid eggs.

I’ll be looking forward to seeing these filled with larvae at next week’s inspection.  The brood pattern from this queen is exceptionally solive.

So, I mulled many names for the hive and for this queen over the past week.  This queen made me search my brain for excellent examples of a “darker” queen.

I finally delved deeply into my Greek Mythology to name my dark beauty and her colony.  I have decided to call this colony, “Hive Olympus” in honor of the home of the Greek Gods.

To match her dark beauty, I chose to name the queen, Hecate.  For those of you who may have forgotten your Greek Mythology (ha ha!), Hecate was the goddess of magic, witchcraft, the night, moon, ghosts, and necromancy.

Since she certainly put a spell on me, the name seems to fit.  Look forward to more tales of Hecate and her bewitching activities in Olympus.

The Stronger Hive – Beatrice

Never one to disappoint, my strongest hive in the bee yard continues its growth pattern.  Sugar syrup disappears in days in this hive.  I mix Honey B Healthy, Super Plus, and Vitamin B Healthy with my 1:1 solution of sugar water.  I’m going to add to my concoction in the near future by adding Amin0-B Booster as well.

I like the mix of essential oils and vitamins that certainly love my kitchen full of the scent of spearmint.  I’ve done quite a bit of reading about the use of essential oils when feeding your bees. It seems there is a preponderance of evidence that supports using these supplements as an aid in knocking back any chance of Nosema in a hive.  Read up on this malady of bees so you will know what to look out for in the future.

This colony is always super active and filled wall-to-wall with bees.  The queen has been actively working at filling frames with eggs.  New larvae are appearing throughout the brood pattern.

Again, this hive was busily building queen cups.  I culled two cups in the supersedure position and two cups in the swarm position.  I have not been able to figure out why they are so intent on producing queens as they have plenty of space with two deeps and one medium as well as having a queen that is solidly laying and creating a near perfect brood pattern.

My bee mentor has suggested taking out a frame or two of honey from the brood boxes and replace it with undrawn comb to stimulate them into thinking they have more space.  I will likely do that next week.

So this hive had me stumped for a name for both the regicidal queen and the colony itself.  So who comes to my rescue but my best friend!

Of course, he was making bee puns all afternoon during my inspection, something that kept my mind off my near heat stroke in the suit in our nice humid weather here in North Carolina.  His suggestion was to name her “Bee-atrice”.  Well I can’t quite go for that spelling but Beatrice stuck.

Keeping with my literary and historical naming conventions, I liked Beatrice since she was the love that Dante Alighieri speaks about in many of his works but most importantly in the Divine Comedy.  Beatrice was Dante’s muse.  Beatrice is an Italian queen so it is fitting to name her hive, Hive Florence, the birthplace of Dante.

The Dreaded Varroa Mite

If you are new to beekeeping and have not done your research, then you need to learn quickly about one of the worst pest’s beekeepers face in managing their colonies, the Varroa Mite.

The Varroa Mite is probably the single, most deadly enemy of our friendly bees.  The mite feeds off of both worker bees and developing brood.  Feeding off the developing pupae, it introduces viruses to the bees which can cause deformed wings and worse.

This nasty little creature was first detected in North Carolina in 1990, just three months after being introduced to the United States just three years earlier.  North Carolina was hit relatively hard by the Varroa Mite with “the number of managed beehives [having] dropped by an estimated 44 percent since the invasion of the mites.

Techniques for Monitoring Varroa Mite Levels

You may have heard lots of information about natural beekeeping, which essentially advocates for no treatment for diseases and pests. In my opinion you should avoid following that advice, as it will likely end with the death of one or more of your colonies.

You must manage Varroa Mites and that means monitoring Varroa Mite levels and treating when levels meet dangerous thresholds.  In my opinion, failing to treat your bees is tantamount to being a bad beekeeper.

Varro Mites threaten the health and well-being of our colonies and we owe it to them to protect them.  There are numerous techniques for monitoring Varroa Mite Levels in your colonies.  All revolve around the concept of Integrated Pest Management (IPM).

Integrated Pest Management (IPM)

Integrated Pest Management is an alternative or replacement for instant use of chemical controls.  IPM takes a holistic view for dealing with Varroa Mites in our hives.  Essentially, IPM is “A combination of biological, cultural, and genetic pest control methods with use of pesticides as the last resort.

IPM considers a targeted species’ life cycle and intervenes in reproduction, growth, or development to reduce the population.  IPM makes use of a number of techniques to help control Varroa Mite levels in hives.   These methods include screened bottom boards, introducing queens with Varroa sensitivity hygiene (VSH), placing hives in full sun, drone frames, and softer chemicals.  Using a combination of techniques will improve the chances that your colonies will make it through winter.

The key to making IPM techniques work for you is remember to monitor Varroa Mite levels on an ongoing basis.  Techniques you might use to monitor Varroa Mite levels include the use of screened bottom boards and sticky boards, the sugar roll, and the ether roll to name a few.

Screened Bottom Boards and Sticky Boards

A screened bottom board relies for effectiveness on the bees dislodging Varroa Mites, which fall through the mesh screen and out of the hive.  You can couple the screened bottom board with a corrugated sheet that you either spray with cooking oil or coat with Vaseline.

Dislodged mites fall through the screened bottom board onto the sticky board.  The beekeeper may then remove the board and get a count of the Varroa Mite Level of the colony.

The Sugar Roll

The powdered sugar roll, or sugar shake, is a commonly used approach that takes a sample of bees from brood comb and measures mite levels by coating the bees in powdered sugar.  Since the Varroa Mite does not like the contact of the powdered sugar, it releases from the bees allowing you to monitor the level of infestation.

A readily available Varroa Mite testing kit supplies the following steps for a sugar roll:

1. Shake bees from a brood frame into a large white tub.  Don’t forget to check for the queen.  If she is present, select a different frame.
2. Pour or scoop bees into the supplied measuring cup and tap it on a hard surface.  Your goal is to fill the cup to 100 ml, approximately 300 bees, for your mite test.
3. Pour the measured bees into the supplied plastic jar and seal with the screened lid.
4. Using your hive tool, press 2 tablespoons of powdered sugar through the screened lid, and shake/roll the jar until all the bees are coated.  Set the bees in the shade for 2 minutes.
5. Tip the sealed jar over the white tub, and shake vigorously up and down for at least 1 minute, allowing all mites to dislodge from the bees and fall into the large container.
6. Count the number of mites you find on the bottom of the white tub.  For a clearer view, add some water to the tub to dissolve the sugar, revealing the oval-shaped, reddish brown mites.
7. Return the sample of bees to their colony.
8. To estimate the number of mites per 100 bees, divide the total mites found in your sample by 3.

Other Methods

There are a number of additional methods for monitoring Varroa Mite levels including the alcohol wash method, the Varroa EasyCheck, and the ether roll.  All are effective at estimating the number of mites attacking your colonies.

A number of test kits are available from the PerfectBee Store.

Varroa Mite Treatments

There are many methods for reducing the number of Varroa Mites in your colonies.  These methods include:

• Oxalic Acid
• Formic Pro
• Apivar
• Apiguard
• Api Life Var
• Apistan Strips

See Medications and Treatments for more details.

As with any chemical, each treatment modality carries its own risks and Apistan Strips are documented as having Varroa Mite resistance to this treatment.  If you choose to treat with Oxalic Acid, treatment should be done in early spring or late fall.  It also requires the purchase of a  vaporizer.

Before you decide on a treatment modality, check out each treatment and make the determination which will work for your purposes.  I have decided to use Apivar as it has a proven track record of over 90% effectiveness against Varroa Mites.  Whichever method you choose, read the instructions carefully and follow them.

Varroa Mite Levels in My Colonies

I have yet to successfully run a sugar roll test for Varroa Mites in my colonies.  In both attempts, I have come up with no mites in the sample which I do not believe is the truth.

I have managed to get a count using the sticky board approach.  I placed a sticky board on my hives on Tuesday evening and removed it on Thursday evening, the recommended time for measuring this.  My results are as follows:

1. Hive Florence – 2.333 mites per 100 bees,
2. Hive Olympus – 1.333 mites per 100 bees, and
3. Hive Acquitaine – 0.667 mites per 100 bees.

Unfortunately, Hive Florence has reached the precautionary level between 2 and 3%.  Since Apivar has an excellent track record in treating Varroa Mites, I will be treating with it in the near future.

Coming Next Week

At this time, I haven’t chosen a topic for next week’s blog post so it will be a surprise (for you and me!).  But, you can be on the look out for more updates about my three colonies.

Until next time, happy beekeeping!