Varroa mites are a severe threat to honey bee colonies, causing significant harm if not detected and treated early. The Varroa Easy Check tool is essential for monitoring mite levels and determining if treatment is necessary.
Varroa mites reproduce quickly , with female mites laying eggs in brood cells, leading to rapid population growth and potential colony collapse if mite levels aren't controlled.
Several methods for mite monitoring are discussed, including alcohol wash, sugar roll, and CO2 injection. Among these, the alcohol wash is highlighted as the most accurate, though it involves sacrificing a small number of bees. Regular monitoring and appropriate treatment are crucial for managing varroa mite infestations.
We can’t overemphasize how awful varroa mites are and how easily they can damage a colony of bees. Fortunately, we have tools to help make them less of a problem. Varroa Easy Check is a tool that you can use to check the varroa mite populations in your honey bee colonies to determine if you need mite treatment or not.
It offers easy varroa infestation monitoring, making it practical and convenient to use multiple methods to monitor varroa infestations in adult bees. It’s an essential tool for checking the “mite load” of your bees so you can know if action needs to be taken or not to help your bees. But before diving into that, let’s talk first about varroa mites.
Varroa mites are one of the most severe pests in honey bee colonies. They are parasitic mites that attack honey bees for survival and reproduction. And they do a very good job of surviving. Australia was the last place with managed bees that didn’t have varroa mites, and they finally found them in 2022.
As its scientific name suggests, Varroa destructors and varroa mites cause significant destruction to the bee population if detected and treated too late. They’re considered the world’s most devastating honey bee pests and cost hobby and commercial beekeepers millions of dollars annually.
The Reproduction Stage
During mite reproduction, female mites enter the brood cells (both on drone and worker brood, but mostly on drone brood) during the pre-capping stage, and after the brood cell is capped, they lay two to five eggs on the larva. Egg-laying occurs in sealed brood where the first egg is male, and the rest are female within a 10-day reproduction cycle. It’s a weird, complicated reproductive cycle where the son mates with it’s sisters. Varroa mites are weird.
Varroa mites undergo two larval stages before developing into adults: protonymph and deutonymph. Male mites develop into adults in 5-6 days, while female mites take 7-8 days.
Male varroa mites die shortly after mating, which occurs exclusively inside the infested brood cell. On the other hand, young female varroa mites will lay eggs again in other brood cells after two weeks. They are the ones that cause all the problems with beekeepers and make it hard to keep bees alive.
Both young female and mother mites emerge from the brood cell as the host bees emerge from the brood frames, and the cycle begins again. This process is how varroa populations can explode quickly. Adult female mites usually live for two months. Just think how many times they can reproduce in that period.
The Phoretic Stage
Adult female varroa mites are the only ones that feed and attach to adult honey bees. Once attached to their host, the phoretic mite will crawl onto the bee’s abdomen to suck and feed on the bee’s equivalent to blood, the hemolymph. This is where they spread much of their diseases to the adult bees.
Due to the very mobile nature of female varroa mites, the mites are easily and rapidly spread among bees, infecting many bees. On the other hand, adult male mite exclusively feeds on larvae and pupae, which means they never leave the brood box after hatching. They are so small it is extremely hard to see them. Let alone see the females.
What Happens to Honey Bee Colonies With High Mite Infestations
The infestation caused by varroa is called varroosis or varroasis, and this condition should be stopped as early as possible to avoid massive damage to your bee colonies and nearby colonies, which is crucial for maintaining honey bee health.
Varroosis can severely weaken healthy bees, as they no longer have enough nutrients necessary for different bodily functions such as immunity, hormone and energy regulation, and pesticide detoxification. This increase in varroa mite levels can cause genetic defects, decreased weight in both hatching and adult bees, and a shorter lifespan.
Varroosis can also lead to other viral infestations since the open wounds left by the sucking of mites can become breeding grounds for other diseases or viral infections, including the famous deformed wing virus (DWV). When the varroa mites are feeding on the bee larva, they all feed from the same wound. You can see how this can really damage a bee.
It goes without saying that all the negative occurrences mentioned above will also result in a noticeable reduction in the colony’s overall ability to prosper.
A high mite count is dangerous because it can reduce the honey bee population, eventually leading to breakdown and colony death if detected and treated too late. Varroa mites capitalize on the bees’ constant repetition of their brood cycle and can easily out-reproduce the
How To Check And Monitor For Varroa Mites
Alcohol Wash
Alcohol wash is recognized as the most reliable, accurate, and economical option in monitoring varroa mite population.
It is done by immersing a sample of sampled bees (about 200 or 300) in alcohol, then shaking the EasyCheck to detach the phoretic mites from the bees so they can then be counted afterward. The alcohol used for the mite wash should have a very high percentage of alcohol in it. Most beekeepers use rubbing alcohol, with a percentage of 70%.
Another great option is to use water and Dawn dish soap. A couple of drops is sufficient for a mite wash. More is not better, as it can create too many bubbles.
Windshield washing fluid made for the winter is another good option for fluid in the Varroa Easycheck.
Though this method is the most consistent in delivering accurate results compared to the other 2 methods, many beekeepers are hesitant to use it because sample bees die after the monitoring because they’re immersed in alcohol.
Though a number of bees indeed have to be “sacrificed,” you have to keep in mind that the 200 or 300 sample bees are usually less than 1% of the total population, and they can be replaced rapidly since a queen bee can lay more or less 2,000 eggs per day.
Filtering Out Varroa From Alcohol
After you use the varroa check, you can re-use the liquid, but you want to be sure to get the varroa mites out. It defeats the purpose of moving the varroa from one test to another.
The filters we like to use to keep our alcohol clean are either a paper towel or a coffee filter. They are small enough to keep the varroa mites out but let the alcohol or windshield washing fluid through so it can be reused.
Sugar Roll
Beekeepers commonly use this method, but we discourage it as it is inaccurate. It does not kill any bees, but you don't get good results from it, so it's not very helpful compared to the previous method. Monitoring and managing varroa mite infestations is crucial to prevent colony collapse, and the sugar roll method offers a less harmful alternative for assessing mite levels.
It is done by putting about two tablespoons of powdered or icing sugar into the transparent bowl of EasyCheck, then putting the sample bees of about 200-300 into the container with the powdered sugar. The white perforated basket is placed "upside down" over the bees. Then closed with the yellow lid. Then swirl the EasyCheck for the sugar to be mixed with the bees, causing the mites to detach from the bees.
After that, remove the yellow lid and shake the powdered sugar from the container through the holes into a container of water. Shake it well to dislodge the bees and let the powdered sugar and the mites to fall through the holes and into the water. When the sugar hits the water, it dissolves, and you can see the mites.
The bees emerged a little upset about being agitated but were otherwise unharmed. Then, the EasyCheck is upside down, removing the sugar into the yellow lid or a bigger container. Then add a bit of water to dissolve the sugar for clear mite counts.
Though this method keeps the sample bees alive , it’s not as accurate as the alcohol wash. This method can be difficult to produce good results when it is humid outside. The humidity in the air can cause the powdered sugar to clump inside the EasyCheck.
CO2 Injections
In this method, the sample bees are anesthetized through exposure to Carbon dioxide gas. The EasyCheck is then gently shaken so the mites can be detached from the bees and pass through the white basket’s holes. The mites are counted, and sample bees are released into the hives or the entrance.
For this, you would set the Easy Check in the same way as the powdered sugar roll, where the bees are put into the transparent container; then, the perforated basket is placed over the bees upside down.
Though this method is said to have similar accurate results as the alcohol wash based on a study conducted in Europe with Apis mellifera, it’s not widely used since the CO2 injector or dispenser and CO2 cartridges are readily available.
This technique only “knocks out” the bees and doesn’t kill them. While the bees are knocked out, the mites are also knocked out and fall off the bees.
How To Manage Varroa Mites
The absence of varroa in bee colonies is every beekeeper’s dream, but unfortunately, not all dreams come true. So, you have to deal with the varroa dilemma once mite populations are confirmed in your beehives.
Managing varroa mites properly will require beekeepers to measure the number of mites in a colony. Measuring is the only way to know if the mite population present on adult bees is exceeding the threshold. Monthly is the ideal monitoring schedule, but most beekeepers check for mites just before and after their normal treatment schedule.
Different mite treatments are already widely available for beekeepers. Varroa mites can be controlled using different approaches such as cultural, mechanical, and chemical. Fortunately, the mite treatments we use now are not as harsh as they used to be. Most of the chemicals available for mite treatments are considered “soft” treatments with organic essential oils as the base.
Oxalic acid treatments are very popular and effective against mites. The most popular way to treat oxalic acid is with a vaporizer or in the form of strips like Varroxsan .
The cultural approach aims to reduce mite populations and treat bees through mite-resistant genetics, brood breaks, and colony splitting.
The mechanical approach, on the other hand, is a mite treatment that aims to kill the mites through physical means, such as a screened bottom board.
Ongoing research scattered around the globe is also happening as bee breeders are experimenting with breeding mite-resistant bees as another alternative to varroa control. This is the ideal approach, but most of the world isn't able to do this yet.
Varroa Economic Threshold
The threshold is often referred to as the “economic threshold,” and it is said that when the mite infestation reaches the threshold, the bee colony will undergo decline and become less productive. If the number of mites keeps increasing after reaching the threshold, the colony will eventually die. The mite population grows exponentially inside the colony while the bee population plummets.
Economic threshold differs from region to region and at different times of the year, but they aim at keeping mite levels below or around a ratio of 3 mites per 100 bees. Fewer mites than the threshold mean you don’t have to treat hives. But If you find more than three mites per 100 bees in your monitoring, you need to act fast in treating varroa since they spread easily and rapidly.
In our example above, using the Varroa EasyCheck , the sample of 300 bees will provide a sample of mites to measure. If in that 300 mites, we found 9 mites, then we would use some type of treatment for the varroa mite population. With less than 9 mites, we consider if the mite population is growing or declining. If there are more than nine mites, we would definitely do something to help the bees.
Your bee colonies must have low levels of varroa mites to avoid significant problems. Make sure to do regular varroa control to know the appropriate action to take to manage varroa properly. Increased mite numbers are an indication that your healthy colonies need immediate attention and action.
Make your mite monitoring easier and faster by using Varroa EasyCheck.
It is easier to keep mite levels low than it is to get high mite levels down
