Successful beekeeping requires healthy hives. It is important to familiarize yourself with common honey bee pests and parasites that can infect your hives so that you can quickly identify and treat them.
Managing Common Honey Bee Pests
Honey Bees (apis mellifera) have a host of pests and diseases to contend with. Here are the 6 most common honey bee pests, what they do, how to identify them, and how to prevent and/or treat them.
6 Pests to Watch For
1. Wax Moths
There are two types of wax moth: the lesser wax moth (Achroia grisella) and greater wax moth (Galleria mellonella). Both species can be detrimental to a weak hive, but the greater wax moth is more common.
What Do Wax Moths Do?
A wax moth will enter the hive by sneaking past guard bees. She will lay eggs inside the brood box and then leave. If the eggs are not removed by house bees, they will hatch and begin to eat the wax, pollen, honey, brood, and anything else they come across as they tunnel through the hive.
This is beneficial in nature because the wax moth larvae will clean out the wax from dead hives. However, it can cause immense damage to weak colonies.
How to Identify Wax Moths
Wax moths leave a distinct webbing behind as they move through each frame which makes them fairly easy to identify.
Look for large, soft, white larvae in the brood comb, chewed through wax, and thick white webbing across the frames.
Wax Moth Prevention and Treatment
Strong colonies are usually able to fight off wax moths on their own by removing the larvae of the greater wax moth from the hive. However, with a high concentration of larvae or weak honey bee colonies, the moths can destroy the entire hive.
There is currently no chemical treatment for wax moths that will not harm your bees, so prevention is the best medicine with these honey bee pests.
To prevent wax moths from entering the hive, you can add a screened entrance reducer that the bees can fit through, but the adult wax moths cannot.
When storing frames with comb, keep them in an area exposed to light and fresh air. This will discourage wax moth infestation.
You can also place frames in a freezer to kill any eggs before storage as well. I had wax moths infesting an empty hive on my homestead a couple of years ago. I took the frames out, cleaned what I could, froze the frames to kill the eggs, then stored them in a locked storage container.
2. Small Hive Beetle
Hive beetles are invasive honey bee pests that eat brood and destroy honey stores.
What Do Hive Beetles Do?
Small Hive Beetles cause honey fermentation as they move through the hive and leave their waste behind. The honey turns into a smelly slime that will cause the bees to abscond.
How to Identify Hive Beetles
Check the top of the inner cover as soon as you open the hive. The hive beetles will run from the light and you will see them scurry around.
Hive beetles look similar to wax moth larvae, but they aren’t soft bodied and they do not leave webs behind.
Hive Beetle Prevention and Treatment
Bees may abandon the hive if there are too many beetles present so it is important to maintain a small beetle load.
One preventative option for these honey bee pests is a ground spray. Since hive beetle larvae burrow into the ground before metamorphosis, the ground spray kills them before they can emerge.
Beetle traps are the most efficient method of treating a hive beetle infestation. There are a few types of beetle traps… The most common are:
- Tray Traps- These traps are similar to sticky boards for varroa mites. The tray slides under the screened bottom board and is filled with cooking oil. Beetles fall through the screen and drown in the oil.
- Beetle Eater / Beetle Buster Traps– These traps are small containers that fit between frames. There is a tray of oil underneath the trap. The beetles run to the holes in the trap to hide and they fall in the oil where they drown.
You could also use Check-Mite strips, but these are not recommended because they introduce chemicals into the hive.
3. Varroa Mites
Varroa mites (aka varroa destructor) are serious pests that almost all beekeepers will deal with at some point.
What Do Varroa Mites Do?
These parasitic mites lay eggs in capped brood cells. The mites attach to the bee larvae and feed on them. They also transmit diseases like deformed wing virus into the larvae.
How to Identify Varroa Mites
Look for these ectoparasitic mites in brood cells, attached to the outside of bee larvae, and on the bottom board of the hive.
Varroa mites can also attach to and feed on adult bees, but it is more common to find them on the larvae.
Varroa Mite Prevention and Treatment
It is important to keep low varroa mite levels in your hives. Check for these honey bee pests routinely using the powdered sugar test or sticky boards.
- The powdered sugar test involves taking a sampling of honey bees (about 300) in a jar with a screened lid. Sprinkle them with powdered sugar and roll the jar around to coat the bees. The sugar will cause the mites to lose their grip and fall off. Shake the mites and sugar out through the screen and release the bees back into the hive. Count the mites to determine how heavy the load in your hive is.
- Sticky boards (Detector Boards)- Coat a white sheet or white piece of paper with a thin layer of cooking oil. Place it under the screened bottom board. Leave it in the hive for 24 hours, then remove and count the mites. If you see more than 50 mites within this 24 hour period, you should consider treating the hive.
Another way to prevent mite issues is to consider keeping bees that are tolerant to varroa mites such as Russian bees.
You can also seek queens from a beekeeper who breeds for Varroa Sensitive Hygiene. VSH is a behavioral trait that causes the honey bees to instinctually remove bee larvae infected by varroa mites.
There are a few different options for treating varroa infestations:
- Apistan and CheckMite– These are plastic strips with poison on them. The mites walk across them and come into contact with the poison. These strips work for a bit, but the mites will quickly build resistance.
- Apiguard and Api-life Var– These varroa mite treatments are essential oil products that reduce mite numbers. These two are good options because they do not harm the bees and they don’t transfer into the beeswax as much as other chemical treatments.
- Mite-Away 2– This is an organic formic acid mite treatment that can be used during honeyflow. A strip can be laid on top of the brood frame to lower the number of live mites in the hive.
4. Tracheal Mite
What Do Tracheal Mites Do?
Tracheal mites (acarapis woodi) are honey bee pests that lay eggs in the trachea of honey bees. After hatching, the mites emerge from the trachea and eat the blood of the infected bees.
How to Identify Tracheal Mites
Tracheal mites are not visible to the naked eye like varroa mites. In order to see them, you would need to inspect a dissected honey bee with a microscope.
You may need to check for mites of you notice:
- bees attempting to fly, but falling to the ground instead
- bees with “K-wings”
- bees stumbling around
Tracheal Mite Prevention and Treatment
Tracheal mites are most easily treated with Menthol pellets (mite-a-thol). Menthol is lethal to tracheal mites, but not harmful to the bees…just a little irritating.
Tracheal mite loads can also be reduced by feeding grease patties to the bees. Grease patties lower the infestation rate by making it difficult for mites to grab onto grease coated honey bees.
Mite-Away 2 can be used to treat tracheal mites in the same way that it treats varroa mites.
If the tracheal mites continue to be an issue within your hive, you may need to consider requeening.
What Do Mice Do to Beehives?
Mice build nests in bee hives during cold weather. They enter the hives seeking warmth and food. They can destroy wax and eat the honey stores. Mice can also chew up the hive boxes, frames, and wooden entrance reducers.
Prevention and Treatment of Mice in Beehives
To keep mice out of your hives, it is best to add a metal entrance reducer / mouse guard to the hive entrance during the winter months. Mice can chew through wooden entrance reducers so it is important to use metal instead.
- Other animal Pests
What Do Animal Pests Do to Beehives?
- Bears- Bears will take hives apart to eat the bee larvae and the honey.
- Skunks- Skunks will scratch at the hive entrance and eat whatever guard bees come out.
- Opossums- Possums don’t work too hard for their meal, they just eat the bees that they can reach easily without scratching.
- Racoons- Racoons will actually open the top of the beehive, remove a frame, and take it to the ground near the hive to eat the contents of the frame.
Preventing Animal Pests
If you have issues with any of these honey bee pests, installing electric fence around the bee yard is the best way to prevent them from entering.
For raccoons specifically, you can place a brick on top of the hive to prevent them from removing the cover.
It is also a good idea to keep trash and old frames away from the hives to reduce temptation.
Common signs of distress in honey bees
If you notice any of the following signs, you should check your hive for honey bee pests or diseases:
- Emergency supercedure cells
- Dead bees at the hive entrance or bottom board
- Spotty brood
- Dead larvae