Varroa Mite Infestation, Testing and Treatment

Presentation by Blake Shook of Desert Creek Honey to the Johnson County Beekeepers Association September 8, 2015

Presentation by Blake Shook of Desert Creek Honey to the Johnson County Beekeepers Association September 8, 2015

Varroa mite infestation in a hive is hard to determine since the mites are so small and not visible through casual observation. You may be able to see them on uncapped larvae but more difficult on adult bees and in capped cells.

The video to the right compares the life cycle of the Varroa Mite to the life cycle of the honey bee.

In his presentation, Blake described the “sugar roll” technique of counting the varroa mites in your hive, his parameters for testing and treatment and some of the medicinal preparations use in treatment.

Equipment Needed

1 Quart Mason Jar with ring style lid (remove ring, discard lid and keep ring)
Cut 1/8” hardware cloth in a circle to fit on top of the jar so that you can screw the ring back on.
Large piece of “white paper”.
6 Tablespoons Powered Sugar

Procedure

Procedure as Blake Described at the Meeting

Take the ring and wire lid off the jar.

Remove a frame from the hive and knock the bees onto the paper by lightly tapping the frame over the paper. Fold the paper in half and funnel the bees into the jar. Continue this process until you have the jar 3/4 full of bees. Replace the wire lid and the ring.

Using all 6 Tablespoons of powdered sugar, sprinkle through the wire lid 1 Tablespoon at a time. Shake the jar and distribute the sugar onto the bees. Repeat until the full 6 Tablespoons are used.

Shake the jar and distribute the sugar until all the bees are coated with the powdered sugar. You can let the jar sit in the sun for 1 to 2 minutes, shake again then, let set another 1 to 2 minutes. Make sure the powdered sugar doesn’t come out the top of the wire lid by placing your hand over the top of the lid.

Treating the jar like a salt shaker, shake the powdered sugar through the wire lid onto the white paper. The mites will not be able to cling to the bees, while covered with the powdered sugar, and will fall through onto the white paper where they will be clearly visible.

Remove the lid from the jar and turn the bees loose. They will look like “ghost bees” flying around but they will be fine and return to the hive and resume their normal “bee duties”.

Alternate Techniques

In the video on the right, Dr Dewey Caron demonstrates how to count mites using 2 techniques of an alcohol wash and a sugar roll.

Level of Infestation

There have been differing opinions as to “how many” mites that appear on the paper constitute a level of infestation sufficient enough to warrant treatment. You will always have a certain level of infestation since hives in Texas almost always have a certain number of mites in them. The goal is to keep the level as low as possible.

In the past, if you saw less than 7 or 8 you didn’t need to treat. However, that number has been more recently been lowered. Now the opinion is 3 to 4 mites is enough to warrant treatment.

Treatment

When to Treat

Many of the medicinal preparations are placed in the hive in strip or gel form and “fume out” over a period of time. You must be sure that the outside temperature is less than 80 so that the products don’t fume out too fast and get so strong and cause the bees to leave.

You should only test and treat in the early Spring and Fall and only when the temperature will stay less than 80 degrees for a 7-10 day period. Note: It is important to pay attention to temperature when testing and treating. You need to be aware of the weather in the region your hive is in. Here in North Texas, we only achieve the required temperatures in mid to late November. In other regions, such as the coast of Texas, the test and treatment period may be as late as January.

When Not To Treat

You should not test or treat during the winter or summer months because of the extreme temperatures.

Medications

All the medications listed below are available through your favorite bee supplier.

Medication	Uses	Application	Treatment Period	Notes
Api Life VAR	Varroa	Break one wafer into 4 pieces and place on the corners of the brood nest. Apply 3 times every 7-10 days	30 day treatment. Temperatures must be between 64-80	Supers can be installed after treatment but cannot be harvested for 30 days.
MiteAway Quick Strip	Varroa	Apply two strips near the edges of the brood box.	7 days. Daytime temperatures must be 50-80 º	Treatment can be done with honey supers on the hive. Strips are compostible.
Apiguard gel	Varroa	If you are using Apiguard in trays: peel back the lid of the tray and place gel side up on top of the brood frames. Make sure to leave enough space for the bees to get into the tray (use a spacer [an eke] or more preferably an empty super on top of the brood chamber). Close the hive. After 2 weeks repeat with a second tray and leave in place for 2 – 4 weeks. If you are using the 3 kg (6.6 lb) tub: use the scoop and spatula to apply 50g Apiguard onto the dosing tray provided. Repeat after 2 weeks and leave in place for a further 2-4 weeks. The ideal total treatment period is 6 weeks.”	Apiguard is best applied in summer or autumn — outside the period of honeyflow. The external temperature should be above 15°C (60°F) which means that the colony is active. Distribution of the Apiguard gel depends on the bees transporting it around the hive during the process of hive cleaning and this activity increases as the external temperature rises. Application during honeyflows should be avoided in case of tainting the honey.	Apiguard can be applied at any time of day but for best results treat colonies in the late afternoon or evening when the temperature is lower and the bees are in or returning to the hive. If the Apiguard can be applied when it is cooler — the rate of sublimation of the gel and the activity of the bee colony is lower and the bees will become accustomed to the odor more readily than if the product is applied at the hottest part of the day when the bees are most active.

Portions of this post are from Brushy Mountain Bee Farm