Traditional or organic? Varroa treatment options
Every beekeeper in New Zealand will be affected by Varroa mites at some stage – and they can be extremely destructive if left untreated. That’s why regular inspections and prompt treatment are crucial to keeping your bees healthy.
In the past, treating Varroa tended to involve synthetic miticides but now, there are organic options available. Your choice depends on your preference and how the mites react to treatment.
Our honeybee experts, renowned bee scientist Dr Mark Goodwin and Research Associate Sarah Cross, have produced a series of videos on the process of checking hives, identifying mites and treating infestations.
Here’s everything you need to know.
Finding weak hives
Ecrotek’s research associate Sarah Cross created a video on how to spot a weak, Varroa-infested hive. Click here to see her in action, or read on to learn more.
If you notice weak brood or fewer bees in your hives, it’s a sign something’s wrong. But to confirm that it’s Varroa, you’ll need to do further investigating and take a frame to inspect more closely.
Checking for Varroa
Unless you have a severe outbreak, it will be hard to spot the mites with the naked eye. A bad brood pattern is a telling sign of a Varroa infection – look for lots of empty space or a frame that isn’t well packed. You also want to look for weak bees. If they are dying frequently or if any have deformed wings, it’s a sign of a Varroa infection.
Severe outbreaks
If a hive is riddled with Varroa, you may be able to see mites on the bees just by looking. Unfortunately, at this stage of infection, there’s not a lot you can do to save your bees and they will likely all die. It’s better to check more frequently so you can treat infections before they get to this level.
Monitoring Varroa
If you can’t see any mites but you suspect you have them, it’s important to run a more thorough check. Read through our blog for detailed instructions about how to check and monitor Varroa.
Treating Varroa with miticides
If a hive is infected, the trick is to treat it as early as possible. Because some mites have become resistant to miticide treatments, they may be ineffective against a serious outbreak.
Apitraz Easy Varroa Strip treatment is one type of miticide. It comes in plastic strips impregnated with a chemical that kills Varroa but doesn’t harm the bees. There are other strip treatments available from different brands.
Here’s how to use a strip treatment:
1. Put gloves on to protect your hands from the chemical strips, and carefully read all safety instructions on the treatment box.
2. Read the specific instructions on your treatment to ensure that you’re using the appropriate number of strips. Insert the strips between frames, then close the hive. The chemical will come off the strips and be distributed around the hive, killing the Varroa. Eventually, the mites will be unable to cling to their bee hosts and will fall to the bottom of the hive.
3. If you have one of our Hive Doctor Smart Bottom Boards on your bee hive you can use a Pest Checking tray to check - the Varroa will fall onto the trays so you can easily count the number of mites.
If your hives are badly infected with Varroa, there isn’t much you can do to save them. The best way to prevent that from happening is to monitor your hives after treatment is removed in the autumn. That way, you can spot high Varroa numbers early and treat them promptly, giving your bees a better chance of survival through to spring.
Importance of additional treatment
Because miticide treatment relies on natural mite fall, there will likely still be many more Varroa mites inside the hive. That’s why it’s essential to keep checking your hives, treating regularly and using other treatment options as needed.
Organic controls for Varroa
Internationally renowned honeybee scientist, Dr Mark Goodwin, explains everything you need to know about organic Varroa treatments.
Check out the video here, or read on to learn more.
The plus side of organic varroa treatments
The advantage of organic products like thymols and oxalic acid is that these products are based on naturally occurring chemicals found in some honey. This means that residues are less of a problem compared with synthetic treatments. Overuse can still leave residues but if you follow instructions carefully, they’re unlikely to be an issue.
Effectiveness of organic products
The real question of organic products is about effectiveness – there isn’t much point in using something that isn’t going to work. As with most products, there are mixed responses from beekeepers – they seem to work well for some and less well for others.
If you would like to use organic products, try them first on a few hives to make sure they work for you – and make sure to check after treatment to see whether it has been effective. A good rule: don’t experiment with more hives than you’re prepared to lose.
The science behind oxalic acid
There’s only been one scientific paper on the effectiveness of oxalic acid. The findings were that it controlled Varroa well in autumn, and colonies were strong going into winter, but it affected the way the colonies built up in the spring.
If you want to test oxalic acid, we recommend using a synthetic varroa treatment for a couple of half apiaries, and organic varroa treatment like oxalic acid for the rest. Then in spring, check which hives are thriving. If there is a difference, you need to weigh up if oxalic acid is working for you or if it’s time to move on to something else.
Treating with Thymovar
Thymovar is a thymol-based, BioGro NZ certified Varroa treatment with an average researched efficacy of 87-97%. The wafers release thymol vapour, which builds to levels that are highly toxic to Varroa mites but safe for bees.
You should use this product in the spring before honey supers have been added for the first honey flow. Here’s how:
1. Open the sealed sachet containing five wafers.
2. Cut one wafer in half with a pair of scissors, and place on top of the brood chamber. For a double-storey box of chambers, use two uncut wafers.
3. Put the wafers on top of the combs of the brood chamber, and then close the hives as usual.
4. Repeat 3-4 weeks later and remove used wafers after a further 3-4 weeks.
Have Varroa treatments worked?
Whichever treatment you decide to use, the most important thing is whether it has worked. Watch our video to see Dr Mark Goodwin explaining how to check your results or read on to learn more.
Resistance to control products
When Varroa treatments were first introduced, they all worked and there wasn’t much need to check them. Now, a lot of Varroa mites have developed a resistance to control products. That means that even if you’ve treated in the autumn, there’s no guarantee your colony will survive until the spring.
Check your hives, save your business
We know of beekeepers who have had big losses because they couldn’t see the value in checking if the treatment worked. For motivation to check your hives, think about what each hive is worth to you, if you’re a commercial beekeeper.
Divide your total income from hives by the number of hives you have for the value of each hive. Keep that in your mind when you’re deciding whether to check them – and think about the financial loss if something were to go wrong. If you’re a hobbyist beekeeper, you likely care deeply about your bees regardless of potential income.
Regular inspections and prompt treatment
Whether you treat varroa with a synthetic or organic product, the most important thing is to check your hives after treatment to make sure it has been effective. With resistance to many Varroa treatments and varied results for different beekeepers, it’s crucial to do this to protect your hives. It’s a lot of work – but a quick check will pay off in the long run.
Looking for Varroa treatments for your hives? Ecrotek has a range of products to help. Check them out on our website!